aboutsummaryrefslogtreecommitdiffstats
path: root/fs/btrfs
AgeCommit message (Collapse)Author
2019-12-10btrfs: silence maybe-uninitialized warning in clone_rangeAustin Kim
commit 431d39887d6273d6d84edf3c2eab09f4200e788a upstream. GCC throws warning message as below: ‘clone_src_i_size’ may be used uninitialized in this function [-Wmaybe-uninitialized] #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) ^ fs/btrfs/send.c:5088:6: note: ‘clone_src_i_size’ was declared here u64 clone_src_i_size; ^ The clone_src_i_size is only used as call-by-reference in a call to get_inode_info(). Silence the warning by initializing clone_src_i_size to 0. Note that the warning is a false positive and reported by older versions of GCC (eg. 7.x) but not eg 9.x. As there have been numerous people, the patch is applied. Setting clone_src_i_size to 0 does not otherwise make sense and would not do any action in case the code changes in the future. Signed-off-by: Austin Kim <austindh.kim@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add note ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-12-10btrfs: qgroup: Always free PREALLOC META reserve in ↵Qu Wenruo
btrfs_delalloc_release_extents() commit 8702ba9396bf7bbae2ab93c94acd4bd37cfa4f09 upstream. [Background] Btrfs qgroup uses two types of reserved space for METADATA space, PERTRANS and PREALLOC. PERTRANS is metadata space reserved for each transaction started by btrfs_start_transaction(). While PREALLOC is for delalloc, where we reserve space before joining a transaction, and finally it will be converted to PERTRANS after the writeback is done. [Inconsistency] However there is inconsistency in how we handle PREALLOC metadata space. The most obvious one is: In btrfs_buffered_write(): btrfs_delalloc_release_extents(BTRFS_I(inode), reserve_bytes, true); We always free qgroup PREALLOC meta space. While in btrfs_truncate_block(): btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, (ret != 0)); We only free qgroup PREALLOC meta space when something went wrong. [The Correct Behavior] The correct behavior should be the one in btrfs_buffered_write(), we should always free PREALLOC metadata space. The reason is, the btrfs_delalloc_* mechanism works by: - Reserve metadata first, even it's not necessary In btrfs_delalloc_reserve_metadata() - Free the unused metadata space Normally in: btrfs_delalloc_release_extents() |- btrfs_inode_rsv_release() Here we do calculation on whether we should release or not. E.g. for 64K buffered write, the metadata rsv works like: /* The first page */ reserve_meta: num_bytes=calc_inode_reservations() free_meta: num_bytes=0 total: num_bytes=calc_inode_reservations() /* The first page caused one outstanding extent, thus needs metadata rsv */ /* The 2nd page */ reserve_meta: num_bytes=calc_inode_reservations() free_meta: num_bytes=calc_inode_reservations() total: not changed /* The 2nd page doesn't cause new outstanding extent, needs no new meta rsv, so we free what we have reserved */ /* The 3rd~16th pages */ reserve_meta: num_bytes=calc_inode_reservations() free_meta: num_bytes=calc_inode_reservations() total: not changed (still space for one outstanding extent) This means, if btrfs_delalloc_release_extents() determines to free some space, then those space should be freed NOW. So for qgroup, we should call btrfs_qgroup_free_meta_prealloc() other than btrfs_qgroup_convert_reserved_meta(). The good news is: - The callers are not that hot The hottest caller is in btrfs_buffered_write(), which is already fixed by commit 336a8bb8e36a ("btrfs: Fix wrong btrfs_delalloc_release_extents parameter"). Thus it's not that easy to cause false EDQUOT. - The trans commit in advance for qgroup would hide the bug Since commit f5fef4593653 ("btrfs: qgroup: Make qgroup async transaction commit more aggressive"), when btrfs qgroup metadata free space is slow, it will try to commit transaction and free the wrongly converted PERTRANS space, so it's not that easy to hit such bug. [FIX] So to fix the problem, remove the @qgroup_free parameter for btrfs_delalloc_release_extents(), and always pass true to btrfs_inode_rsv_release(). Reported-by: Filipe Manana <fdmanana@suse.com> Fixes: 43b18595d660 ("btrfs: qgroup: Use separate meta reservation type for delalloc") CC: stable@vger.kernel.org # 4.19+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-12-10Btrfs: fix inode cache block reserve leak on failure to allocate data spaceFilipe Manana
commit 29d47d00e0ae61668ee0c5d90bef2893c8abbafa upstream. If we failed to allocate the data extent(s) for the inode space cache, we were bailing out without releasing the previously reserved metadata. This was triggering the following warnings when unmounting a filesystem: $ cat -n fs/btrfs/inode.c (...) 9268 void btrfs_destroy_inode(struct inode *inode) 9269 { (...) 9276 WARN_ON(BTRFS_I(inode)->block_rsv.reserved); 9277 WARN_ON(BTRFS_I(inode)->block_rsv.size); (...) 9281 WARN_ON(BTRFS_I(inode)->csum_bytes); 9282 WARN_ON(BTRFS_I(inode)->defrag_bytes); (...) Several fstests test cases triggered this often, such as generic/083, generic/102, generic/172, generic/269 and generic/300 at least, producing stack traces like the following in dmesg/syslog: [82039.079546] WARNING: CPU: 2 PID: 13167 at fs/btrfs/inode.c:9276 btrfs_destroy_inode+0x203/0x270 [btrfs] (...) [82039.081543] CPU: 2 PID: 13167 Comm: umount Tainted: G W 5.2.0-rc4-btrfs-next-50 #1 [82039.081912] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [82039.082673] RIP: 0010:btrfs_destroy_inode+0x203/0x270 [btrfs] (...) [82039.083913] RSP: 0018:ffffac0b426a7d30 EFLAGS: 00010206 [82039.084320] RAX: ffff8ddf77691158 RBX: ffff8dde29b34660 RCX: 0000000000000002 [82039.084736] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8dde29b34660 [82039.085156] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000 [82039.085578] R10: ffffac0b426a7c90 R11: ffffffffb9aad768 R12: ffffac0b426a7db0 [82039.086000] R13: ffff8ddf5fbec0a0 R14: dead000000000100 R15: 0000000000000000 [82039.086416] FS: 00007f8db96d12c0(0000) GS:ffff8de036b00000(0000) knlGS:0000000000000000 [82039.086837] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [82039.087253] CR2: 0000000001416108 CR3: 00000002315cc001 CR4: 00000000003606e0 [82039.087672] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [82039.088089] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [82039.088504] Call Trace: [82039.088918] destroy_inode+0x3b/0x70 [82039.089340] btrfs_free_fs_root+0x16/0xa0 [btrfs] [82039.089768] btrfs_free_fs_roots+0xd8/0x160 [btrfs] [82039.090183] ? wait_for_completion+0x65/0x1a0 [82039.090607] close_ctree+0x172/0x370 [btrfs] [82039.091021] generic_shutdown_super+0x6c/0x110 [82039.091427] kill_anon_super+0xe/0x30 [82039.091832] btrfs_kill_super+0x12/0xa0 [btrfs] [82039.092233] deactivate_locked_super+0x3a/0x70 [82039.092636] cleanup_mnt+0x3b/0x80 [82039.093039] task_work_run+0x93/0xc0 [82039.093457] exit_to_usermode_loop+0xfa/0x100 [82039.093856] do_syscall_64+0x162/0x1d0 [82039.094244] entry_SYSCALL_64_after_hwframe+0x49/0xbe [82039.094634] RIP: 0033:0x7f8db8fbab37 (...) [82039.095876] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [82039.096290] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37 [82039.096700] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240 [82039.097110] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015 [82039.097522] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64 [82039.097937] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0 [82039.098350] irq event stamp: 0 [82039.098750] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [82039.099150] hardirqs last disabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00 [82039.099545] softirqs last enabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00 [82039.099925] softirqs last disabled at (0): [<0000000000000000>] 0x0 [82039.100292] ---[ end trace f2521afa616ddccc ]--- [82039.100707] WARNING: CPU: 2 PID: 13167 at fs/btrfs/inode.c:9277 btrfs_destroy_inode+0x1ac/0x270 [btrfs] (...) [82039.103050] CPU: 2 PID: 13167 Comm: umount Tainted: G W 5.2.0-rc4-btrfs-next-50 #1 [82039.103428] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [82039.104203] RIP: 0010:btrfs_destroy_inode+0x1ac/0x270 [btrfs] (...) [82039.105461] RSP: 0018:ffffac0b426a7d30 EFLAGS: 00010206 [82039.105866] RAX: ffff8ddf77691158 RBX: ffff8dde29b34660 RCX: 0000000000000002 [82039.106270] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8dde29b34660 [82039.106673] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000 [82039.107078] R10: ffffac0b426a7c90 R11: ffffffffb9aad768 R12: ffffac0b426a7db0 [82039.107487] R13: ffff8ddf5fbec0a0 R14: dead000000000100 R15: 0000000000000000 [82039.107894] FS: 00007f8db96d12c0(0000) GS:ffff8de036b00000(0000) knlGS:0000000000000000 [82039.108309] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [82039.108723] CR2: 0000000001416108 CR3: 00000002315cc001 CR4: 00000000003606e0 [82039.109146] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [82039.109567] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [82039.109989] Call Trace: [82039.110405] destroy_inode+0x3b/0x70 [82039.110830] btrfs_free_fs_root+0x16/0xa0 [btrfs] [82039.111257] btrfs_free_fs_roots+0xd8/0x160 [btrfs] [82039.111675] ? wait_for_completion+0x65/0x1a0 [82039.112101] close_ctree+0x172/0x370 [btrfs] [82039.112519] generic_shutdown_super+0x6c/0x110 [82039.112988] kill_anon_super+0xe/0x30 [82039.113439] btrfs_kill_super+0x12/0xa0 [btrfs] [82039.113861] deactivate_locked_super+0x3a/0x70 [82039.114278] cleanup_mnt+0x3b/0x80 [82039.114685] task_work_run+0x93/0xc0 [82039.115083] exit_to_usermode_loop+0xfa/0x100 [82039.115476] do_syscall_64+0x162/0x1d0 [82039.115863] entry_SYSCALL_64_after_hwframe+0x49/0xbe [82039.116254] RIP: 0033:0x7f8db8fbab37 (...) [82039.117463] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [82039.117882] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37 [82039.118330] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240 [82039.118743] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015 [82039.119159] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64 [82039.119574] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0 [82039.119987] irq event stamp: 0 [82039.120387] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [82039.120787] hardirqs last disabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00 [82039.121182] softirqs last enabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00 [82039.121563] softirqs last disabled at (0): [<0000000000000000>] 0x0 [82039.121933] ---[ end trace f2521afa616ddccd ]--- [82039.122353] WARNING: CPU: 2 PID: 13167 at fs/btrfs/inode.c:9278 btrfs_destroy_inode+0x1bc/0x270 [btrfs] (...) [82039.124606] CPU: 2 PID: 13167 Comm: umount Tainted: G W 5.2.0-rc4-btrfs-next-50 #1 [82039.125008] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [82039.125801] RIP: 0010:btrfs_destroy_inode+0x1bc/0x270 [btrfs] (...) [82039.126998] RSP: 0018:ffffac0b426a7d30 EFLAGS: 00010202 [82039.127399] RAX: ffff8ddf77691158 RBX: ffff8dde29b34660 RCX: 0000000000000002 [82039.127803] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8dde29b34660 [82039.128206] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000 [82039.128611] R10: ffffac0b426a7c90 R11: ffffffffb9aad768 R12: ffffac0b426a7db0 [82039.129020] R13: ffff8ddf5fbec0a0 R14: dead000000000100 R15: 0000000000000000 [82039.129428] FS: 00007f8db96d12c0(0000) GS:ffff8de036b00000(0000) knlGS:0000000000000000 [82039.129846] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [82039.130261] CR2: 0000000001416108 CR3: 00000002315cc001 CR4: 00000000003606e0 [82039.130684] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [82039.131142] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [82039.131561] Call Trace: [82039.131990] destroy_inode+0x3b/0x70 [82039.132417] btrfs_free_fs_root+0x16/0xa0 [btrfs] [82039.132844] btrfs_free_fs_roots+0xd8/0x160 [btrfs] [82039.133262] ? wait_for_completion+0x65/0x1a0 [82039.133688] close_ctree+0x172/0x370 [btrfs] [82039.134157] generic_shutdown_super+0x6c/0x110 [82039.134575] kill_anon_super+0xe/0x30 [82039.134997] btrfs_kill_super+0x12/0xa0 [btrfs] [82039.135415] deactivate_locked_super+0x3a/0x70 [82039.135832] cleanup_mnt+0x3b/0x80 [82039.136239] task_work_run+0x93/0xc0 [82039.136637] exit_to_usermode_loop+0xfa/0x100 [82039.137029] do_syscall_64+0x162/0x1d0 [82039.137418] entry_SYSCALL_64_after_hwframe+0x49/0xbe [82039.137812] RIP: 0033:0x7f8db8fbab37 (...) [82039.139059] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [82039.139475] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37 [82039.139890] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240 [82039.140302] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015 [82039.140719] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64 [82039.141138] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0 [82039.141597] irq event stamp: 0 [82039.142043] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [82039.142443] hardirqs last disabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00 [82039.142839] softirqs last enabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00 [82039.143220] softirqs last disabled at (0): [<0000000000000000>] 0x0 [82039.143588] ---[ end trace f2521afa616ddcce ]--- [82039.167472] WARNING: CPU: 3 PID: 13167 at fs/btrfs/extent-tree.c:10120 btrfs_free_block_groups+0x30d/0x460 [btrfs] (...) [82039.173800] CPU: 3 PID: 13167 Comm: umount Tainted: G W 5.2.0-rc4-btrfs-next-50 #1 [82039.174847] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [82039.177031] RIP: 0010:btrfs_free_block_groups+0x30d/0x460 [btrfs] (...) [82039.180397] RSP: 0018:ffffac0b426a7dd8 EFLAGS: 00010206 [82039.181574] RAX: ffff8de010a1db40 RBX: ffff8de010a1db40 RCX: 0000000000170014 [82039.182711] RDX: ffff8ddff4380040 RSI: ffff8de010a1da58 RDI: 0000000000000246 [82039.183817] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000 [82039.184925] R10: ffff8de036404380 R11: ffffffffb8a5ea00 R12: ffff8de010a1b2b8 [82039.186090] R13: ffff8de010a1b2b8 R14: 0000000000000000 R15: dead000000000100 [82039.187208] FS: 00007f8db96d12c0(0000) GS:ffff8de036b80000(0000) knlGS:0000000000000000 [82039.188345] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [82039.189481] CR2: 00007fb044005170 CR3: 00000002315cc006 CR4: 00000000003606e0 [82039.190674] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [82039.191829] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [82039.192978] Call Trace: [82039.194160] close_ctree+0x19a/0x370 [btrfs] [82039.195315] generic_shutdown_super+0x6c/0x110 [82039.196486] kill_anon_super+0xe/0x30 [82039.197645] btrfs_kill_super+0x12/0xa0 [btrfs] [82039.198696] deactivate_locked_super+0x3a/0x70 [82039.199619] cleanup_mnt+0x3b/0x80 [82039.200559] task_work_run+0x93/0xc0 [82039.201505] exit_to_usermode_loop+0xfa/0x100 [82039.202436] do_syscall_64+0x162/0x1d0 [82039.203339] entry_SYSCALL_64_after_hwframe+0x49/0xbe [82039.204091] RIP: 0033:0x7f8db8fbab37 (...) [82039.206360] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 [82039.207132] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37 [82039.207906] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240 [82039.208621] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015 [82039.209285] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64 [82039.209984] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0 [82039.210642] irq event stamp: 0 [82039.211306] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [82039.211971] hardirqs last disabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00 [82039.212643] softirqs last enabled at (0): [<ffffffffb7884ff2>] copy_process.part.33+0x7f2/0x1f00 [82039.213304] softirqs last disabled at (0): [<0000000000000000>] 0x0 [82039.213875] ---[ end trace f2521afa616ddccf ]--- Fix this by releasing the reserved metadata on failure to allocate data extent(s) for the inode cache. Fixes: 69fe2d75dd91d0 ("btrfs: make the delalloc block rsv per inode") Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-25btrfs: tracepoints: Fix wrong parameter order for qgroup eventsQu Wenruo
commit fd2b007eaec898564e269d1f478a2da0380ecf51 upstream. [BUG] For btrfs:qgroup_meta_reserve event, the trace event can output garbage: qgroup_meta_reserve: 9c7f6acc-b342-4037-bc47-7f6e4d2232d7: refroot=5(FS_TREE) type=DATA diff=2 The diff should always be alinged to sector size (4k), so there is definitely something wrong. [CAUSE] For the wrong @diff, it's caused by wrong parameter order. The correct parameters are: struct btrfs_root, s64 diff, int type. However the parameters used are: struct btrfs_root, int type, s64 diff. Fixes: 4ee0d8832c2e ("btrfs: qgroup: Update trace events for metadata reservation") CC: stable@vger.kernel.org # 4.19+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-25Btrfs: check for the full sync flag while holding the inode lock during fsyncFilipe Manana
commit ba0b084ac309283db6e329785c1dc4f45fdbd379 upstream. We were checking for the full fsync flag in the inode before locking the inode, which is racy, since at that that time it might not be set but after we acquire the inode lock some other task set it. One case where this can happen is on a system low on memory and some concurrent task failed to allocate an extent map and therefore set the full sync flag on the inode, to force the next fsync to work in full mode. A consequence of missing the full fsync flag set is hitting the problems fixed by commit 0c713cbab620 ("Btrfs: fix race between ranged fsync and writeback of adjacent ranges"), BUG_ON() when dropping extents from a log tree, hitting assertion failures at tree-log.c:copy_items() or all sorts of weird inconsistencies after replaying a log due to file extents items representing ranges that overlap. So just move the check such that it's done after locking the inode and before starting writeback again. Fixes: 0c713cbab620 ("Btrfs: fix race between ranged fsync and writeback of adjacent ranges") CC: stable@vger.kernel.org # 5.2+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-25Btrfs: fix qgroup double free after failure to reserve metadata for delallocFilipe Manana
commit c7967fc1499beb9b70bb9d33525fb0b384af8883 upstream. If we fail to reserve metadata for delalloc operations we end up releasing the previously reserved qgroup amount twice, once explicitly under the 'out_qgroup' label by calling btrfs_qgroup_free_meta_prealloc() and once again, under label 'out_fail', by calling btrfs_inode_rsv_release() with a value of 'true' for its 'qgroup_free' argument, which results in btrfs_qgroup_free_meta_prealloc() being called again, so we end up having a double free. Also if we fail to reserve the necessary qgroup amount, we jump to the label 'out_fail', which calls btrfs_inode_rsv_release() and that in turns calls btrfs_qgroup_free_meta_prealloc(), even though we weren't able to reserve any qgroup amount. So we freed some amount we never reserved. So fix this by removing the call to btrfs_inode_rsv_release() in the failure path, since it's not necessary at all as we haven't changed the inode's block reserve in any way at this point. Fixes: c8eaeac7b73434 ("btrfs: reserve delalloc metadata differently") CC: stable@vger.kernel.org # 5.2+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [PG: adapt for different file name in older code base.] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-25btrfs: don't needlessly create extent-refs kernel threadDavid Sterba
commit 80ed4548d0711d15ca51be5dee0ff813051cfc90 upstream. The patch 32b593bfcb58 ("Btrfs: remove no longer used function to run delayed refs asynchronously") removed the async delayed refs but the thread has been created, without any use. Remove it to avoid resource consumption. Fixes: 32b593bfcb58 ("Btrfs: remove no longer used function to run delayed refs asynchronously") CC: stable@vger.kernel.org # 5.2+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-25Btrfs: add missing extents release on file extent cluster relocation errorFilipe Manana
commit 44db1216efe37bf670f8d1019cdc41658d84baf5 upstream. If we error out when finding a page at relocate_file_extent_cluster(), we need to release the outstanding extents counter on the relocation inode, set by the previous call to btrfs_delalloc_reserve_metadata(), otherwise the inode's block reserve size can never decrease to zero and metadata space is leaked. Therefore add a call to btrfs_delalloc_release_extents() in case we can't find the target page. Fixes: 8b62f87bad9c ("Btrfs: rework outstanding_extents") CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-25btrfs: block-group: Fix a memory leak due to missing btrfs_put_block_group()Qu Wenruo
commit 4b654acdae850f48b8250b9a578a4eaa518c7a6f upstream. In btrfs_read_block_groups(), if we have an invalid block group which has mixed type (DATA|METADATA) while the fs doesn't have MIXED_GROUPS feature, we error out without freeing the block group cache. This patch will add the missing btrfs_put_block_group() to prevent memory leak. Note for stable backports: the file to patch in versions <= 5.3 is fs/btrfs/extent-tree.c Fixes: 49303381f19a ("Btrfs: bail out if block group has different mixed flag") CC: stable@vger.kernel.org # 4.9+ Reviewed-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> [PG: adapt for different file name in older code base.] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-09btrfs: fix uninitialized ret in ref-verifyJosef Bacik
commit c5f4987e86f6692fdb12533ea1fc7a7bb98e555a upstream. Coverity caught a case where we could return with a uninitialized value in ret in process_leaf. This is actually pretty likely because we could very easily run into a block group item key and have a garbage value in ret and think there was an errror. Fix this by initializing ret to 0. Reported-by: Colin Ian King <colin.king@canonical.com> Fixes: fd708b81d972 ("Btrfs: add a extent ref verify tool") CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-09btrfs: fix incorrect updating of log root treeJosef Bacik
commit 4203e968947071586a98b5314fd7ffdea3b4f971 upstream. We've historically had reports of being unable to mount file systems because the tree log root couldn't be read. Usually this is the "parent transid failure", but could be any of the related errors, including "fsid mismatch" or "bad tree block", depending on which block got allocated. The modification of the individual log root items are serialized on the per-log root root_mutex. This means that any modification to the per-subvol log root_item is completely protected. However we update the root item in the log root tree outside of the log root tree log_mutex. We do this in order to allow multiple subvolumes to be updated in each log transaction. This is problematic however because when we are writing the log root tree out we update the super block with the _current_ log root node information. Since these two operations happen independently of each other, you can end up updating the log root tree in between writing out the dirty blocks and setting the super block to point at the current root. This means we'll point at the new root node that hasn't been written out, instead of the one we should be pointing at. Thus whatever garbage or old block we end up pointing at complains when we mount the file system later and try to replay the log. Fix this by copying the log's root item into a local root item copy. Then once we're safely under the log_root_tree->log_mutex we update the root item in the log_root_tree. This way we do not modify the log_root_tree while we're committing it, fixing the problem. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Chris Mason <clm@fb.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-09Btrfs: fix memory leak due to concurrent append writes with fiemapFilipe Manana
commit c67d970f0ea8dcc423e112137d34334fa0abb8ec upstream. When we have a buffered write that starts at an offset greater than or equals to the file's size happening concurrently with a full ranged fiemap, we can end up leaking an extent state structure. Suppose we have a file with a size of 1Mb, and before the buffered write and fiemap are performed, it has a single extent state in its io tree representing the range from 0 to 1Mb, with the EXTENT_DELALLOC bit set. The following sequence diagram shows how the memory leak happens if a fiemap a buffered write, starting at offset 1Mb and with a length of 4Kb, are performed concurrently. CPU 1 CPU 2 extent_fiemap() --> it's a full ranged fiemap range from 0 to LLONG_MAX - 1 (9223372036854775807) --> locks range in the inode's io tree --> after this we have 2 extent states in the io tree: --> 1 for range [0, 1Mb[ with the bits EXTENT_LOCKED and EXTENT_DELALLOC_BITS set --> 1 for the range [1Mb, LLONG_MAX[ with the EXTENT_LOCKED bit set --> start buffered write at offset 1Mb with a length of 4Kb btrfs_file_write_iter() btrfs_buffered_write() --> cached_state is NULL lock_and_cleanup_extent_if_need() --> returns 0 and does not lock range because it starts at current i_size / eof --> cached_state remains NULL btrfs_dirty_pages() btrfs_set_extent_delalloc() (...) __set_extent_bit() --> splits extent state for range [1Mb, LLONG_MAX[ and now we have 2 extent states: --> one for the range [1Mb, 1Mb + 4Kb[ with EXTENT_LOCKED set --> another one for the range [1Mb + 4Kb, LLONG_MAX[ with EXTENT_LOCKED set as well --> sets EXTENT_DELALLOC on the extent state for the range [1Mb, 1Mb + 4Kb[ --> caches extent state [1Mb, 1Mb + 4Kb[ into @cached_state because it has the bit EXTENT_LOCKED set --> btrfs_buffered_write() ends up with a non-NULL cached_state and never calls anything to release its reference on it, resulting in a memory leak Fix this by calling free_extent_state() on cached_state if the range was not locked by lock_and_cleanup_extent_if_need(). The same issue can happen if anything else other than fiemap locks a range that covers eof and beyond. This could be triggered, sporadically, by test case generic/561 from the fstests suite, which makes duperemove run concurrently with fsstress, and duperemove does plenty of calls to fiemap. When CONFIG_BTRFS_DEBUG is set the leak is reported in dmesg/syslog when removing the btrfs module with a message like the following: [77100.039461] BTRFS: state leak: start 6574080 end 6582271 state 16402 in tree 0 refs 1 Otherwise (CONFIG_BTRFS_DEBUG not set) detectable with kmemleak. CC: stable@vger.kernel.org # 4.16+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-09btrfs: fix balance convert to single on 32-bit host CPUsZygo Blaxell
commit 7a54789074a54f64addf5b49bf1994f478337a83 upstream. Currently, the command: btrfs balance start -dconvert=single,soft . on a Raspberry Pi produces the following kernel message: BTRFS error (device mmcblk0p2): balance: invalid convert data profile single This fails because we use is_power_of_2(unsigned long) to validate the new data profile, the constant for 'single' profile uses bit 48, and there are only 32 bits in a long on ARM. Fix by open-coding the check using u64 variables. Tested by completing the original balance command on several Raspberry Pis. Fixes: 818255feece6 ("btrfs: use common helper instead of open coding a bit test") CC: stable@vger.kernel.org # 4.20+ Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-09btrfs: allocate new inode in NOFS contextJosef Bacik
commit 11a19a90870ea5496a8ded69b86f5b476b6d3355 upstream. A user reported a lockdep splat ====================================================== WARNING: possible circular locking dependency detected 5.2.11-gentoo #2 Not tainted ------------------------------------------------------ kswapd0/711 is trying to acquire lock: 000000007777a663 (sb_internal){.+.+}, at: start_transaction+0x3a8/0x500 but task is already holding lock: 000000000ba86300 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}: kmem_cache_alloc+0x1f/0x1c0 btrfs_alloc_inode+0x1f/0x260 alloc_inode+0x16/0xa0 new_inode+0xe/0xb0 btrfs_new_inode+0x70/0x610 btrfs_symlink+0xd0/0x420 vfs_symlink+0x9c/0x100 do_symlinkat+0x66/0xe0 do_syscall_64+0x55/0x1c0 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (sb_internal){.+.+}: __sb_start_write+0xf6/0x150 start_transaction+0x3a8/0x500 btrfs_commit_inode_delayed_inode+0x59/0x110 btrfs_evict_inode+0x19e/0x4c0 evict+0xbc/0x1f0 inode_lru_isolate+0x113/0x190 __list_lru_walk_one.isra.4+0x5c/0x100 list_lru_walk_one+0x32/0x50 prune_icache_sb+0x36/0x80 super_cache_scan+0x14a/0x1d0 do_shrink_slab+0x131/0x320 shrink_node+0xf7/0x380 balance_pgdat+0x2d5/0x640 kswapd+0x2ba/0x5e0 kthread+0x147/0x160 ret_from_fork+0x24/0x30 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(sb_internal); lock(fs_reclaim); lock(sb_internal); *** DEADLOCK *** 3 locks held by kswapd0/711: #0: 000000000ba86300 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x30 #1: 000000004a5100f8 (shrinker_rwsem){++++}, at: shrink_node+0x9a/0x380 #2: 00000000f956fa46 (&type->s_umount_key#30){++++}, at: super_cache_scan+0x35/0x1d0 stack backtrace: CPU: 7 PID: 711 Comm: kswapd0 Not tainted 5.2.11-gentoo #2 Hardware name: Dell Inc. Precision Tower 3620/0MWYPT, BIOS 2.4.2 09/29/2017 Call Trace: dump_stack+0x85/0xc7 print_circular_bug.cold.40+0x1d9/0x235 __lock_acquire+0x18b1/0x1f00 lock_acquire+0xa6/0x170 ? start_transaction+0x3a8/0x500 __sb_start_write+0xf6/0x150 ? start_transaction+0x3a8/0x500 start_transaction+0x3a8/0x500 btrfs_commit_inode_delayed_inode+0x59/0x110 btrfs_evict_inode+0x19e/0x4c0 ? var_wake_function+0x20/0x20 evict+0xbc/0x1f0 inode_lru_isolate+0x113/0x190 ? discard_new_inode+0xc0/0xc0 __list_lru_walk_one.isra.4+0x5c/0x100 ? discard_new_inode+0xc0/0xc0 list_lru_walk_one+0x32/0x50 prune_icache_sb+0x36/0x80 super_cache_scan+0x14a/0x1d0 do_shrink_slab+0x131/0x320 shrink_node+0xf7/0x380 balance_pgdat+0x2d5/0x640 kswapd+0x2ba/0x5e0 ? __wake_up_common_lock+0x90/0x90 kthread+0x147/0x160 ? balance_pgdat+0x640/0x640 ? __kthread_create_on_node+0x160/0x160 ret_from_fork+0x24/0x30 This is because btrfs_new_inode() calls new_inode() under the transaction. We could probably move the new_inode() outside of this but for now just wrap it in memalloc_nofs_save(). Reported-by: Zdenek Sojka <zsojka@seznam.cz> Fixes: 712e36c5f2a7 ("btrfs: use GFP_KERNEL in btrfs_alloc_inode") CC: stable@vger.kernel.org # 4.16+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-09btrfs: relocation: fix use-after-free on dead relocation rootsQu Wenruo
commit 1fac4a54374f7ef385938f3c6cf7649c0fe4f6cd upstream. [BUG] One user reported a reproducible KASAN report about use-after-free: BTRFS info (device sdi1): balance: start -dvrange=1256811659264..1256811659265 BTRFS info (device sdi1): relocating block group 1256811659264 flags data|raid0 ================================================================== BUG: KASAN: use-after-free in btrfs_init_reloc_root+0x2cd/0x340 [btrfs] Write of size 8 at addr ffff88856f671710 by task kworker/u24:10/261579 CPU: 2 PID: 261579 Comm: kworker/u24:10 Tainted: P OE 5.2.11-arch1-1-kasan #4 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./X99 Extreme4, BIOS P3.80 04/06/2018 Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs] Call Trace: dump_stack+0x7b/0xba print_address_description+0x6c/0x22e ? btrfs_init_reloc_root+0x2cd/0x340 [btrfs] __kasan_report.cold+0x1b/0x3b ? btrfs_init_reloc_root+0x2cd/0x340 [btrfs] kasan_report+0x12/0x17 __asan_report_store8_noabort+0x17/0x20 btrfs_init_reloc_root+0x2cd/0x340 [btrfs] record_root_in_trans+0x2a0/0x370 [btrfs] btrfs_record_root_in_trans+0xf4/0x140 [btrfs] start_transaction+0x1ab/0xe90 [btrfs] btrfs_join_transaction+0x1d/0x20 [btrfs] btrfs_finish_ordered_io+0x7bf/0x18a0 [btrfs] ? lock_repin_lock+0x400/0x400 ? __kmem_cache_shutdown.cold+0x140/0x1ad ? btrfs_unlink_subvol+0x9b0/0x9b0 [btrfs] finish_ordered_fn+0x15/0x20 [btrfs] normal_work_helper+0x1bd/0xca0 [btrfs] ? process_one_work+0x819/0x1720 ? kasan_check_read+0x11/0x20 btrfs_endio_write_helper+0x12/0x20 [btrfs] process_one_work+0x8c9/0x1720 ? pwq_dec_nr_in_flight+0x2f0/0x2f0 ? worker_thread+0x1d9/0x1030 worker_thread+0x98/0x1030 kthread+0x2bb/0x3b0 ? process_one_work+0x1720/0x1720 ? kthread_park+0x120/0x120 ret_from_fork+0x35/0x40 Allocated by task 369692: __kasan_kmalloc.part.0+0x44/0xc0 __kasan_kmalloc.constprop.0+0xba/0xc0 kasan_kmalloc+0x9/0x10 kmem_cache_alloc_trace+0x138/0x260 btrfs_read_tree_root+0x92/0x360 [btrfs] btrfs_read_fs_root+0x10/0xb0 [btrfs] create_reloc_root+0x47d/0xa10 [btrfs] btrfs_init_reloc_root+0x1e2/0x340 [btrfs] record_root_in_trans+0x2a0/0x370 [btrfs] btrfs_record_root_in_trans+0xf4/0x140 [btrfs] start_transaction+0x1ab/0xe90 [btrfs] btrfs_start_transaction+0x1e/0x20 [btrfs] __btrfs_prealloc_file_range+0x1c2/0xa00 [btrfs] btrfs_prealloc_file_range+0x13/0x20 [btrfs] prealloc_file_extent_cluster+0x29f/0x570 [btrfs] relocate_file_extent_cluster+0x193/0xc30 [btrfs] relocate_data_extent+0x1f8/0x490 [btrfs] relocate_block_group+0x600/0x1060 [btrfs] btrfs_relocate_block_group+0x3a0/0xa00 [btrfs] btrfs_relocate_chunk+0x9e/0x180 [btrfs] btrfs_balance+0x14e4/0x2fc0 [btrfs] btrfs_ioctl_balance+0x47f/0x640 [btrfs] btrfs_ioctl+0x119d/0x8380 [btrfs] do_vfs_ioctl+0x9f5/0x1060 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x73/0xb0 do_syscall_64+0xa5/0x370 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 369692: __kasan_slab_free+0x14f/0x210 kasan_slab_free+0xe/0x10 kfree+0xd8/0x270 btrfs_drop_snapshot+0x154c/0x1eb0 [btrfs] clean_dirty_subvols+0x227/0x340 [btrfs] relocate_block_group+0x972/0x1060 [btrfs] btrfs_relocate_block_group+0x3a0/0xa00 [btrfs] btrfs_relocate_chunk+0x9e/0x180 [btrfs] btrfs_balance+0x14e4/0x2fc0 [btrfs] btrfs_ioctl_balance+0x47f/0x640 [btrfs] btrfs_ioctl+0x119d/0x8380 [btrfs] do_vfs_ioctl+0x9f5/0x1060 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x73/0xb0 do_syscall_64+0xa5/0x370 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88856f671100 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 1552 bytes inside of 4096-byte region [ffff88856f671100, ffff88856f672100) The buggy address belongs to the page: page:ffffea0015bd9c00 refcount:1 mapcount:0 mapping:ffff88864400e600 index:0x0 compound_mapcount: 0 flags: 0x2ffff0000010200(slab|head) raw: 02ffff0000010200 dead000000000100 dead000000000200 ffff88864400e600 raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88856f671600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88856f671680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88856f671700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88856f671780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88856f671800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== BTRFS info (device sdi1): 1 enospc errors during balance BTRFS info (device sdi1): balance: ended with status: -28 [CAUSE] The problem happens when finish_ordered_io() get called with balance still running, while the reloc root of that subvolume is already dead. (Tree is swap already done, but tree not yet deleted for possible qgroup usage.) That means root->reloc_root still exists, but that reloc_root can be under btrfs_drop_snapshot(), thus we shouldn't access it. The following race could cause the use-after-free problem: CPU1 | CPU2 -------------------------------------------------------------------------- | relocate_block_group() | |- unset_reloc_control(rc) | |- btrfs_commit_transaction() btrfs_finish_ordered_io() | |- clean_dirty_subvols() |- btrfs_join_transaction() | | |- record_root_in_trans() | | |- btrfs_init_reloc_root() | | |- if (root->reloc_root) | | | | |- root->reloc_root = NULL | | |- btrfs_drop_snapshot(reloc_root); |- reloc_root->last_trans| = trans->transid | ^^^^^^^^^^^^^^^^^^^^^^ Use after free [FIX] Fix it by the following modifications: - Test if the root has dead reloc tree before accessing root->reloc_root If the root has BTRFS_ROOT_DEAD_RELOC_TREE, then we don't need to create or update root->reloc_tree - Clear the BTRFS_ROOT_DEAD_RELOC_TREE flag until we have fully dropped reloc tree To co-operate with above modification, so as long as BTRFS_ROOT_DEAD_RELOC_TREE is still set, we won't try to re-create reloc tree at record_root_in_trans(). Reported-by: Cebtenzzre <cebtenzzre@gmail.com> Fixes: d2311e698578 ("btrfs: relocation: Delay reloc tree deletion after merge_reloc_roots") CC: stable@vger.kernel.org # 5.1+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-11-09Btrfs: fix selftests failure due to uninitialized i_mode in test inodesFilipe Manana
commit 9f7fec0ba89108b9385f1b9fb167861224912a4a upstream. Some of the self tests create a test inode, setup some extents and then do calls to btrfs_get_extent() to test that the corresponding extent maps exist and are correct. However btrfs_get_extent(), since the 5.2 merge window, now errors out when it finds a regular or prealloc extent for an inode that does not correspond to a regular file (its ->i_mode is not S_IFREG). This causes the self tests to fail sometimes, specially when KASAN, slub_debug and page poisoning are enabled: $ modprobe btrfs modprobe: ERROR: could not insert 'btrfs': Invalid argument $ dmesg [ 9414.691648] Btrfs loaded, crc32c=crc32c-intel, debug=on, assert=on, integrity-checker=on, ref-verify=on [ 9414.692655] BTRFS: selftest: sectorsize: 4096 nodesize: 4096 [ 9414.692658] BTRFS: selftest: running btrfs free space cache tests [ 9414.692918] BTRFS: selftest: running extent only tests [ 9414.693061] BTRFS: selftest: running bitmap only tests [ 9414.693366] BTRFS: selftest: running bitmap and extent tests [ 9414.696455] BTRFS: selftest: running space stealing from bitmap to extent tests [ 9414.697131] BTRFS: selftest: running extent buffer operation tests [ 9414.697133] BTRFS: selftest: running btrfs_split_item tests [ 9414.697564] BTRFS: selftest: running extent I/O tests [ 9414.697583] BTRFS: selftest: running find delalloc tests [ 9415.081125] BTRFS: selftest: running find_first_clear_extent_bit test [ 9415.081278] BTRFS: selftest: running extent buffer bitmap tests [ 9415.124192] BTRFS: selftest: running inode tests [ 9415.124195] BTRFS: selftest: running btrfs_get_extent tests [ 9415.127909] BTRFS: selftest: running hole first btrfs_get_extent test [ 9415.128343] BTRFS critical (device (efault)): regular/prealloc extent found for non-regular inode 256 [ 9415.131428] BTRFS: selftest: fs/btrfs/tests/inode-tests.c:904 expected a real extent, got 0 This happens because the test inodes are created without ever initializing the i_mode field of the inode, and neither VFS's new_inode() nor the btrfs callback btrfs_alloc_inode() initialize the i_mode. Initialization of the i_mode is done through the various callbacks used by the VFS to create new inodes (regular files, directories, symlinks, tmpfiles, etc), which all call btrfs_new_inode() which in turn calls inode_init_owner(), which sets the inode's i_mode. Since the tests only uses new_inode() to create the test inodes, the i_mode was never initialized. This always happens on a VM I used with kasan, slub_debug and many other debug facilities enabled. It also happened to someone who reported this on bugzilla (on a 5.3-rc). Fix this by setting i_mode to S_IFREG at btrfs_new_test_inode(). Fixes: 6bf9e4bd6a2778 ("btrfs: inode: Verify inode mode to avoid NULL pointer dereference") Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204397 Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2019-10-05Btrfs: fix race setting up and completing qgroup rescan workersFilipe Manana
commit 13fc1d271a2e3ab8a02071e711add01fab9271f6 upstream. There is a race between setting up a qgroup rescan worker and completing a qgroup rescan worker that can lead to callers of the qgroup rescan wait ioctl to either not wait for the rescan worker to complete or to hang forever due to missing wake ups. The following diagram shows a sequence of steps that illustrates the race. CPU 1 CPU 2 CPU 3 btrfs_ioctl_quota_rescan() btrfs_qgroup_rescan() qgroup_rescan_init() mutex_lock(&fs_info->qgroup_rescan_lock) spin_lock(&fs_info->qgroup_lock) fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN init_completion( &fs_info->qgroup_rescan_completion) fs_info->qgroup_rescan_running = true mutex_unlock(&fs_info->qgroup_rescan_lock) spin_unlock(&fs_info->qgroup_lock) btrfs_init_work() --> starts the worker btrfs_qgroup_rescan_worker() mutex_lock(&fs_info->qgroup_rescan_lock) fs_info->qgroup_flags &= ~BTRFS_QGROUP_STATUS_FLAG_RESCAN mutex_unlock(&fs_info->qgroup_rescan_lock) starts transaction, updates qgroup status item, etc btrfs_ioctl_quota_rescan() btrfs_qgroup_rescan() qgroup_rescan_init() mutex_lock(&fs_info->qgroup_rescan_lock) spin_lock(&fs_info->qgroup_lock) fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN init_completion( &fs_info->qgroup_rescan_completion) fs_info->qgroup_rescan_running = true mutex_unlock(&fs_info->qgroup_rescan_lock) spin_unlock(&fs_info->qgroup_lock) btrfs_init_work() --> starts another worker mutex_lock(&fs_info->qgroup_rescan_lock) fs_info->qgroup_rescan_running = false mutex_unlock(&fs_info->qgroup_rescan_lock) complete_all(&fs_info->qgroup_rescan_completion) Before the rescan worker started by the task at CPU 3 completes, if another task calls btrfs_ioctl_quota_rescan(), it will get -EINPROGRESS because the flag BTRFS_QGROUP_STATUS_FLAG_RESCAN is set at fs_info->qgroup_flags, which is expected and correct behaviour. However if other task calls btrfs_ioctl_quota_rescan_wait() before the rescan worker started by the task at CPU 3 completes, it will return immediately without waiting for the new rescan worker to complete, because fs_info->qgroup_rescan_running is set to false by CPU 2. This race is making test case btrfs/171 (from fstests) to fail often: btrfs/171 9s ... - output mismatch (see /home/fdmanana/git/hub/xfstests/results//btrfs/171.out.bad) # --- tests/btrfs/171.out 2018-09-16 21:30:48.505104287 +0100 # +++ /home/fdmanana/git/hub/xfstests/results//btrfs/171.out.bad 2019-09-19 02:01:36.938486039 +0100 # @@ -1,2 +1,3 @@ # QA output created by 171 # +ERROR: quota rescan failed: Operation now in progress # Silence is golden # ... # (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/btrfs/171.out /home/fdmanana/git/hub/xfstests/results//btrfs/171.out.bad' to see the entire diff) That is because the test calls the btrfs-progs commands "qgroup quota rescan -w", "qgroup assign" and "qgroup remove" in a sequence that makes calls to the rescan start ioctl fail with -EINPROGRESS (note the "btrfs" commands 'qgroup assign' and 'qgroup remove' often call the rescan start ioctl after calling the qgroup assign ioctl, btrfs_ioctl_qgroup_assign()), since previous waits didn't actually wait for a rescan worker to complete. Another problem the race can cause is missing wake ups for waiters, since the call to complete_all() happens outside a critical section and after clearing the flag BTRFS_QGROUP_STATUS_FLAG_RESCAN. In the sequence diagram above, if we have a waiter for the first rescan task (executed by CPU 2), then fs_info->qgroup_rescan_completion.wait is not empty, and if after the rescan worker clears BTRFS_QGROUP_STATUS_FLAG_RESCAN and before it calls complete_all() against fs_info->qgroup_rescan_completion, the task at CPU 3 calls init_completion() against fs_info->qgroup_rescan_completion which re-initilizes its wait queue to an empty queue, therefore causing the rescan worker at CPU 2 to call complete_all() against an empty queue, never waking up the task waiting for that rescan worker. Fix this by clearing BTRFS_QGROUP_STATUS_FLAG_RESCAN and setting fs_info->qgroup_rescan_running to false in the same critical section, delimited by the mutex fs_info->qgroup_rescan_lock, as well as doing the call to complete_all() in that same critical section. This gives the protection needed to avoid rescan wait ioctl callers not waiting for a running rescan worker and the lost wake ups problem, since setting that rescan flag and boolean as well as initializing the wait queue is done already in a critical section delimited by that mutex (at qgroup_rescan_init()). Fixes: 57254b6ebce4ce ("Btrfs: add ioctl to wait for qgroup rescan completion") Fixes: d2c609b834d62f ("btrfs: properly track when rescan worker is running") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05btrfs: qgroup: Fix reserved data space leak if we have multiple reserve callsQu Wenruo
commit d4e204948fe3e0dc8e1fbf3f8f3290c9c2823be3 upstream. [BUG] The following script can cause btrfs qgroup data space leak: mkfs.btrfs -f $dev mount $dev -o nospace_cache $mnt btrfs subv create $mnt/subv btrfs quota en $mnt btrfs quota rescan -w $mnt btrfs qgroup limit 128m $mnt/subv for (( i = 0; i < 3; i++)); do # Create 3 64M holes for latter fallocate to fail truncate -s 192m $mnt/subv/file xfs_io -c "pwrite 64m 4k" $mnt/subv/file > /dev/null xfs_io -c "pwrite 128m 4k" $mnt/subv/file > /dev/null sync # it's supposed to fail, and each failure will leak at least 64M # data space xfs_io -f -c "falloc 0 192m" $mnt/subv/file &> /dev/null rm $mnt/subv/file sync done # Shouldn't fail after we removed the file xfs_io -f -c "falloc 0 64m" $mnt/subv/file [CAUSE] Btrfs qgroup data reserve code allow multiple reservations to happen on a single extent_changeset: E.g: btrfs_qgroup_reserve_data(inode, &data_reserved, 0, SZ_1M); btrfs_qgroup_reserve_data(inode, &data_reserved, SZ_1M, SZ_2M); btrfs_qgroup_reserve_data(inode, &data_reserved, 0, SZ_4M); Btrfs qgroup code has its internal tracking to make sure we don't double-reserve in above example. The only pattern utilizing this feature is in the main while loop of btrfs_fallocate() function. However btrfs_qgroup_reserve_data()'s error handling has a bug in that on error it clears all ranges in the io_tree with EXTENT_QGROUP_RESERVED flag but doesn't free previously reserved bytes. This bug has a two fold effect: - Clearing EXTENT_QGROUP_RESERVED ranges This is the correct behavior, but it prevents btrfs_qgroup_check_reserved_leak() to catch the leakage as the detector is purely EXTENT_QGROUP_RESERVED flag based. - Leak the previously reserved data bytes. The bug manifests when N calls to btrfs_qgroup_reserve_data are made and the last one fails, leaking space reserved in the previous ones. [FIX] Also free previously reserved data bytes when btrfs_qgroup_reserve_data fails. Fixes: 524725537023 ("btrfs: qgroup: Introduce btrfs_qgroup_reserve_data function") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05btrfs: qgroup: Fix the wrong target io_tree when freeing reserved data spaceQu Wenruo
commit bab32fc069ce8829c416e8737c119f62a57970f9 upstream. [BUG] Under the following case with qgroup enabled, if some error happened after we have reserved delalloc space, then in error handling path, we could cause qgroup data space leakage: From btrfs_truncate_block() in inode.c: ret = btrfs_delalloc_reserve_space(inode, &data_reserved, block_start, blocksize); if (ret) goto out; again: page = find_or_create_page(mapping, index, mask); if (!page) { btrfs_delalloc_release_space(inode, data_reserved, block_start, blocksize, true); btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, true); ret = -ENOMEM; goto out; } [CAUSE] In the above case, btrfs_delalloc_reserve_space() will call btrfs_qgroup_reserve_data() and mark the io_tree range with EXTENT_QGROUP_RESERVED flag. In the error handling path, we have the following call stack: btrfs_delalloc_release_space() |- btrfs_free_reserved_data_space() |- btrsf_qgroup_free_data() |- __btrfs_qgroup_release_data(reserved=@reserved, free=1) |- qgroup_free_reserved_data(reserved=@reserved) |- clear_record_extent_bits(); |- freed += changeset.bytes_changed; However due to a completion bug, qgroup_free_reserved_data() will clear EXTENT_QGROUP_RESERVED flag in BTRFS_I(inode)->io_failure_tree, other than the correct BTRFS_I(inode)->io_tree. Since io_failure_tree is never marked with that flag, btrfs_qgroup_free_data() will not free any data reserved space at all, causing a leakage. This type of error handling can only be triggered by errors outside of qgroup code. So EDQUOT error from qgroup can't trigger it. [FIX] Fix the wrong target io_tree. Reported-by: Josef Bacik <josef@toxicpanda.com> Fixes: bc42bda22345 ("btrfs: qgroup: Fix qgroup reserved space underflow by only freeing reserved ranges") CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05btrfs: adjust dirty_metadata_bytes after writeback failure of extent bufferDennis Zhou
commit eb5b64f142504a597d67e2109d603055ff765e52 upstream. Before, if a eb failed to write out, we would end up triggering a BUG_ON(). As of f4340622e0226 ("btrfs: extent_io: Move the BUG_ON() in flush_write_bio() one level up"), we no longer BUG_ON(), so we should make life consistent and add back the unwritten bytes to dirty_metadata_bytes. Fixes: f4340622e022 ("btrfs: extent_io: Move the BUG_ON() in flush_write_bio() one level up") CC: stable@vger.kernel.org # 5.2+ Reviewed-by: Filipe Manana <fdmanana@kernel.org> Signed-off-by: Dennis Zhou <dennis@kernel.org> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05btrfs: Relinquish CPUs in btrfs_compare_treesNikolay Borisov
commit 6af112b11a4bc1b560f60a618ac9c1dcefe9836e upstream. When doing any form of incremental send the parent and the child trees need to be compared via btrfs_compare_trees. This can result in long loop chains without ever relinquishing the CPU. This causes softlockup detector to trigger when comparing trees with a lot of items. Example report: watchdog: BUG: soft lockup - CPU#0 stuck for 24s! [snapperd:16153] CPU: 0 PID: 16153 Comm: snapperd Not tainted 5.2.9-1-default #1 openSUSE Tumbleweed (unreleased) Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 pstate: 40000005 (nZcv daif -PAN -UAO) pc : __ll_sc_arch_atomic_sub_return+0x14/0x20 lr : btrfs_release_extent_buffer_pages+0xe0/0x1e8 [btrfs] sp : ffff00001273b7e0 Call trace: __ll_sc_arch_atomic_sub_return+0x14/0x20 release_extent_buffer+0xdc/0x120 [btrfs] free_extent_buffer.part.0+0xb0/0x118 [btrfs] free_extent_buffer+0x24/0x30 [btrfs] btrfs_release_path+0x4c/0xa0 [btrfs] btrfs_free_path.part.0+0x20/0x40 [btrfs] btrfs_free_path+0x24/0x30 [btrfs] get_inode_info+0xa8/0xf8 [btrfs] finish_inode_if_needed+0xe0/0x6d8 [btrfs] changed_cb+0x9c/0x410 [btrfs] btrfs_compare_trees+0x284/0x648 [btrfs] send_subvol+0x33c/0x520 [btrfs] btrfs_ioctl_send+0x8a0/0xaf0 [btrfs] btrfs_ioctl+0x199c/0x2288 [btrfs] do_vfs_ioctl+0x4b0/0x820 ksys_ioctl+0x84/0xb8 __arm64_sys_ioctl+0x28/0x38 el0_svc_common.constprop.0+0x7c/0x188 el0_svc_handler+0x34/0x90 el0_svc+0x8/0xc Fix this by adding a call to cond_resched at the beginning of the main loop in btrfs_compare_trees. Fixes: 7069830a9e38 ("Btrfs: add btrfs_compare_trees function") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05Btrfs: fix use-after-free when using the tree modification logFilipe Manana
commit efad8a853ad2057f96664328a0d327a05ce39c76 upstream. At ctree.c:get_old_root(), we are accessing a root's header owner field after we have freed the respective extent buffer. This results in an use-after-free that can lead to crashes, and when CONFIG_DEBUG_PAGEALLOC is set, results in a stack trace like the following: [ 3876.799331] stack segment: 0000 [#1] SMP DEBUG_PAGEALLOC PTI [ 3876.799363] CPU: 0 PID: 15436 Comm: pool Not tainted 5.3.0-rc3-btrfs-next-54 #1 [ 3876.799385] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014 [ 3876.799433] RIP: 0010:btrfs_search_old_slot+0x652/0xd80 [btrfs] (...) [ 3876.799502] RSP: 0018:ffff9f08c1a2f9f0 EFLAGS: 00010286 [ 3876.799518] RAX: ffff8dd300000000 RBX: ffff8dd85a7a9348 RCX: 000000038da26000 [ 3876.799538] RDX: 0000000000000000 RSI: ffffe522ce368980 RDI: 0000000000000246 [ 3876.799559] RBP: dae1922adadad000 R08: 0000000008020000 R09: ffffe522c0000000 [ 3876.799579] R10: ffff8dd57fd788c8 R11: 000000007511b030 R12: ffff8dd781ddc000 [ 3876.799599] R13: ffff8dd9e6240578 R14: ffff8dd6896f7a88 R15: ffff8dd688cf90b8 [ 3876.799620] FS: 00007f23ddd97700(0000) GS:ffff8dda20200000(0000) knlGS:0000000000000000 [ 3876.799643] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3876.799660] CR2: 00007f23d4024000 CR3: 0000000710bb0005 CR4: 00000000003606f0 [ 3876.799682] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3876.799703] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3876.799723] Call Trace: [ 3876.799735] ? do_raw_spin_unlock+0x49/0xc0 [ 3876.799749] ? _raw_spin_unlock+0x24/0x30 [ 3876.799779] resolve_indirect_refs+0x1eb/0xc80 [btrfs] [ 3876.799810] find_parent_nodes+0x38d/0x1180 [btrfs] [ 3876.799841] btrfs_check_shared+0x11a/0x1d0 [btrfs] [ 3876.799870] ? extent_fiemap+0x598/0x6e0 [btrfs] [ 3876.799895] extent_fiemap+0x598/0x6e0 [btrfs] [ 3876.799913] do_vfs_ioctl+0x45a/0x700 [ 3876.799926] ksys_ioctl+0x70/0x80 [ 3876.799938] ? trace_hardirqs_off_thunk+0x1a/0x20 [ 3876.799953] __x64_sys_ioctl+0x16/0x20 [ 3876.799965] do_syscall_64+0x62/0x220 [ 3876.799977] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 3876.799993] RIP: 0033:0x7f23e0013dd7 (...) [ 3876.800056] RSP: 002b:00007f23ddd96ca8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 3876.800078] RAX: ffffffffffffffda RBX: 00007f23d80210f8 RCX: 00007f23e0013dd7 [ 3876.800099] RDX: 00007f23d80210f8 RSI: 00000000c020660b RDI: 0000000000000003 [ 3876.800626] RBP: 000055fa2a2a2440 R08: 0000000000000000 R09: 00007f23ddd96d7c [ 3876.801143] R10: 00007f23d8022000 R11: 0000000000000246 R12: 00007f23ddd96d80 [ 3876.801662] R13: 00007f23ddd96d78 R14: 00007f23d80210f0 R15: 00007f23ddd96d80 (...) [ 3876.805107] ---[ end trace e53161e179ef04f9 ]--- Fix that by saving the root's header owner field into a local variable before freeing the root's extent buffer, and then use that local variable when needed. Fixes: 30b0463a9394d9 ("Btrfs: fix accessing the root pointer in tree mod log functions") CC: stable@vger.kernel.org # 3.10+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05btrfs: fix allocation of free space cache v1 bitmap pagesChristophe Leroy
commit 3acd48507dc43eeeb0a1fe965b8bad91cab904a7 upstream. Various notifications of type "BUG kmalloc-4096 () : Redzone overwritten" have been observed recently in various parts of the kernel. After some time, it has been made a relation with the use of BTRFS filesystem and with SLUB_DEBUG turned on. [ 22.809700] BUG kmalloc-4096 (Tainted: G W ): Redzone overwritten [ 22.810286] INFO: 0xbe1a5921-0xfbfc06cd. First byte 0x0 instead of 0xcc [ 22.810866] INFO: Allocated in __load_free_space_cache+0x588/0x780 [btrfs] age=22 cpu=0 pid=224 [ 22.811193] __slab_alloc.constprop.26+0x44/0x70 [ 22.811345] kmem_cache_alloc_trace+0xf0/0x2ec [ 22.811588] __load_free_space_cache+0x588/0x780 [btrfs] [ 22.811848] load_free_space_cache+0xf4/0x1b0 [btrfs] [ 22.812090] cache_block_group+0x1d0/0x3d0 [btrfs] [ 22.812321] find_free_extent+0x680/0x12a4 [btrfs] [ 22.812549] btrfs_reserve_extent+0xec/0x220 [btrfs] [ 22.812785] btrfs_alloc_tree_block+0x178/0x5f4 [btrfs] [ 22.813032] __btrfs_cow_block+0x150/0x5d4 [btrfs] [ 22.813262] btrfs_cow_block+0x194/0x298 [btrfs] [ 22.813484] commit_cowonly_roots+0x44/0x294 [btrfs] [ 22.813718] btrfs_commit_transaction+0x63c/0xc0c [btrfs] [ 22.813973] close_ctree+0xf8/0x2a4 [btrfs] [ 22.814107] generic_shutdown_super+0x80/0x110 [ 22.814250] kill_anon_super+0x18/0x30 [ 22.814437] btrfs_kill_super+0x18/0x90 [btrfs] [ 22.814590] INFO: Freed in proc_cgroup_show+0xc0/0x248 age=41 cpu=0 pid=83 [ 22.814841] proc_cgroup_show+0xc0/0x248 [ 22.814967] proc_single_show+0x54/0x98 [ 22.815086] seq_read+0x278/0x45c [ 22.815190] __vfs_read+0x28/0x17c [ 22.815289] vfs_read+0xa8/0x14c [ 22.815381] ksys_read+0x50/0x94 [ 22.815475] ret_from_syscall+0x0/0x38 Commit 69d2480456d1 ("btrfs: use copy_page for copying pages instead of memcpy") changed the way bitmap blocks are copied. But allthough bitmaps have the size of a page, they were allocated with kzalloc(). Most of the time, kzalloc() allocates aligned blocks of memory, so copy_page() can be used. But when some debug options like SLAB_DEBUG are activated, kzalloc() may return unaligned pointer. On powerpc, memcpy(), copy_page() and other copying functions use 'dcbz' instruction which provides an entire zeroed cacheline to avoid memory read when the intention is to overwrite a full line. Functions like memcpy() are writen to care about partial cachelines at the start and end of the destination, but copy_page() assumes it gets pages. As pages are naturally cache aligned, copy_page() doesn't care about partial lines. This means that when copy_page() is called with a misaligned pointer, a few leading bytes are zeroed. To fix it, allocate bitmaps through kmem_cache instead of using kzalloc() The cache pool is created with PAGE_SIZE alignment constraint. Reported-by: Erhard F. <erhard_f@mailbox.org> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204371 Fixes: 69d2480456d1 ("btrfs: use copy_page for copying pages instead of memcpy") Cc: stable@vger.kernel.org # 4.19+ Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: David Sterba <dsterba@suse.com> [ rename to btrfs_free_space_bitmap ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-05btrfs: Detect unbalanced tree with empty leaf before crashing btree operationsQu Wenruo
[ Upstream commit 62fdaa52a3d00a875da771719b6dc537ca79fce1 ] [BUG] With crafted image, btrfs will panic at btree operations: kernel BUG at fs/btrfs/ctree.c:3894! invalid opcode: 0000 [#1] SMP PTI CPU: 0 PID: 1138 Comm: btrfs-transacti Not tainted 5.0.0-rc8+ #9 RIP: 0010:__push_leaf_left+0x6b6/0x6e0 RSP: 0018:ffffc0bd4128b990 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffa0a4ab8f0e38 RCX: 0000000000000000 RDX: ffffa0a280000000 RSI: 0000000000000000 RDI: ffffa0a4b3814000 RBP: ffffc0bd4128ba38 R08: 0000000000001000 R09: ffffc0bd4128b948 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000240 R13: ffffa0a4b556fb60 R14: ffffa0a4ab8f0af0 R15: ffffa0a4ab8f0af0 FS: 0000000000000000(0000) GS:ffffa0a4b7a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2461c80020 CR3: 000000022b32a006 CR4: 00000000000206f0 Call Trace: ? _cond_resched+0x1a/0x50 push_leaf_left+0x179/0x190 btrfs_del_items+0x316/0x470 btrfs_del_csums+0x215/0x3a0 __btrfs_free_extent.isra.72+0x5a7/0xbe0 __btrfs_run_delayed_refs+0x539/0x1120 btrfs_run_delayed_refs+0xdb/0x1b0 btrfs_commit_transaction+0x52/0x950 ? start_transaction+0x94/0x450 transaction_kthread+0x163/0x190 kthread+0x105/0x140 ? btrfs_cleanup_transaction+0x560/0x560 ? kthread_destroy_worker+0x50/0x50 ret_from_fork+0x35/0x40 Modules linked in: ---[ end trace c2425e6e89b5558f ]--- [CAUSE] The offending csum tree looks like this: checksum tree key (CSUM_TREE ROOT_ITEM 0) node 29741056 level 1 items 14 free 107 generation 19 owner CSUM_TREE ... key (EXTENT_CSUM EXTENT_CSUM 85975040) block 29630464 gen 17 key (EXTENT_CSUM EXTENT_CSUM 89911296) block 29642752 gen 17 <<< key (EXTENT_CSUM EXTENT_CSUM 92274688) block 29646848 gen 17 ... leaf 29630464 items 6 free space 1 generation 17 owner CSUM_TREE item 0 key (EXTENT_CSUM EXTENT_CSUM 85975040) itemoff 3987 itemsize 8 range start 85975040 end 85983232 length 8192 ... leaf 29642752 items 0 free space 3995 generation 17 owner 0 ^ empty leaf invalid owner ^ leaf 29646848 items 1 free space 602 generation 17 owner CSUM_TREE item 0 key (EXTENT_CSUM EXTENT_CSUM 92274688) itemoff 627 itemsize 3368 range start 92274688 end 95723520 length 3448832 So we have a corrupted csum tree where one tree leaf is completely empty, causing unbalanced btree, thus leading to unexpected btree balance error. [FIX] For this particular case, we handle it in two directions to catch it: - Check if the tree block is empty through btrfs_verify_level_key() So that invalid tree blocks won't be read out through btrfs_search_slot() and its variants. - Check 0 tree owner in tree checker NO tree is using 0 as its tree owner, detect it and reject at tree block read time. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202821 Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05btrfs: tree-checker: Add ROOT_ITEM checkQu Wenruo
[ Upstream commit 259ee7754b6793af8bdd77f9ca818bc41cfe9541 ] This patch will introduce ROOT_ITEM check, which includes: - Key->objectid and key->offset check Currently only some easy check, e.g. 0 as rootid is invalid. - Item size check Root item size is fixed. - Generation checks Generation, generation_v2 and last_snapshot should not be greater than super generation + 1 - Level and alignment check Level should be in [0, 7], and bytenr must be aligned to sector size. - Flags check Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203261 Reported-by: Jungyeon Yoon <jungyeon.yoon@gmail.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05btrfs: extent-tree: Make sure we only allocate extents from block groups ↵Qu Wenruo
with the same type [ Upstream commit 2a28468e525f3924efed7f29f2bc5a2926e7e19a ] [BUG] With fuzzed image and MIXED_GROUPS super flag, we can hit the following BUG_ON(): kernel BUG at fs/btrfs/delayed-ref.c:491! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 1849 Comm: sync Tainted: G O 5.2.0-custom #27 RIP: 0010:update_existing_head_ref.cold+0x44/0x46 [btrfs] Call Trace: add_delayed_ref_head+0x20c/0x2d0 [btrfs] btrfs_add_delayed_tree_ref+0x1fc/0x490 [btrfs] btrfs_free_tree_block+0x123/0x380 [btrfs] __btrfs_cow_block+0x435/0x500 [btrfs] btrfs_cow_block+0x110/0x240 [btrfs] btrfs_search_slot+0x230/0xa00 [btrfs] ? __lock_acquire+0x105e/0x1e20 btrfs_insert_empty_items+0x67/0xc0 [btrfs] alloc_reserved_file_extent+0x9e/0x340 [btrfs] __btrfs_run_delayed_refs+0x78e/0x1240 [btrfs] ? kvm_clock_read+0x18/0x30 ? __sched_clock_gtod_offset+0x21/0x50 btrfs_run_delayed_refs.part.0+0x4e/0x180 [btrfs] btrfs_run_delayed_refs+0x23/0x30 [btrfs] btrfs_commit_transaction+0x53/0x9f0 [btrfs] btrfs_sync_fs+0x7c/0x1c0 [btrfs] ? __ia32_sys_fdatasync+0x20/0x20 sync_fs_one_sb+0x23/0x30 iterate_supers+0x95/0x100 ksys_sync+0x62/0xb0 __ia32_sys_sync+0xe/0x20 do_syscall_64+0x65/0x240 entry_SYSCALL_64_after_hwframe+0x49/0xbe [CAUSE] This situation is caused by several factors: - Fuzzed image The extent tree of this fs missed one backref for extent tree root. So we can allocated space from that slot. - MIXED_BG feature Super block has MIXED_BG flag. - No mixed block groups exists All block groups are just regular ones. This makes data space_info->block_groups[] contains metadata block groups. And when we reserve space for data, we can use space in metadata block group. Then we hit the following file operations: - fallocate We need to allocate data extents. find_free_extent() choose to use the metadata block to allocate space from, and choose the space of extent tree root, since its backref is missing. This generate one delayed ref head with is_data = 1. - extent tree update We need to update extent tree at run_delayed_ref time. This generate one delayed ref head with is_data = 0, for the same bytenr of old extent tree root. Then we trigger the BUG_ON(). [FIX] The quick fix here is to check block_group->flags before using it. The problem can only happen for MIXED_GROUPS fs. Regular filesystems won't have space_info with DATA|METADATA flag, and no way to hit the bug. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203255 Reported-by: Jungyeon Yoon <jungyeon.yoon@gmail.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-05btrfs: delayed-inode: Kill the BUG_ON() in btrfs_delete_delayed_dir_index()Qu Wenruo
[ Upstream commit 933c22a7512c5c09b1fdc46b557384efe8d03233 ] There is one report of fuzzed image which leads to BUG_ON() in btrfs_delete_delayed_dir_index(). Although that fuzzed image can already be addressed by enhanced extent-tree error handler, it's still better to hunt down more BUG_ON(). This patch will hunt down two BUG_ON()s in btrfs_delete_delayed_dir_index(): - One for error from btrfs_delayed_item_reserve_metadata() Instead of BUG_ON(), we output an error message and free the item. And return the error. All callers of this function handles the error by aborting current trasaction. - One for possible EEXIST from __btrfs_add_delayed_deletion_item() That function can return -EEXIST. We already have a good enough error message for that, only need to clean up the reserved metadata space and allocated item. To help above cleanup, also modifiy __btrfs_remove_delayed_item() called in btrfs_release_delayed_item(), to skip unassociated item. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203253 Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-19Btrfs: fix assertion failure during fsync and use of stale transactionFilipe Manana
commit 410f954cb1d1c79ae485dd83a175f21954fd87cd upstream. Sometimes when fsync'ing a file we need to log that other inodes exist and when we need to do that we acquire a reference on the inodes and then drop that reference using iput() after logging them. That generally is not a problem except if we end up doing the final iput() (dropping the last reference) on the inode and that inode has a link count of 0, which can happen in a very short time window if the logging path gets a reference on the inode while it's being unlinked. In that case we end up getting the eviction callback, btrfs_evict_inode(), invoked through the iput() call chain which needs to drop all of the inode's items from its subvolume btree, and in order to do that, it needs to join a transaction at the helper function evict_refill_and_join(). However because the task previously started a transaction at the fsync handler, btrfs_sync_file(), it has current->journal_info already pointing to a transaction handle and therefore evict_refill_and_join() will get that transaction handle from btrfs_join_transaction(). From this point on, two different problems can happen: 1) evict_refill_and_join() will often change the transaction handle's block reserve (->block_rsv) and set its ->bytes_reserved field to a value greater than 0. If evict_refill_and_join() never commits the transaction, the eviction handler ends up decreasing the reference count (->use_count) of the transaction handle through the call to btrfs_end_transaction(), and after that point we have a transaction handle with a NULL ->block_rsv (which is the value prior to the transaction join from evict_refill_and_join()) and a ->bytes_reserved value greater than 0. If after the eviction/iput completes the inode logging path hits an error or it decides that it must fallback to a transaction commit, the btrfs fsync handle, btrfs_sync_file(), gets a non-zero value from btrfs_log_dentry_safe(), and because of that non-zero value it tries to commit the transaction using a handle with a NULL ->block_rsv and a non-zero ->bytes_reserved value. This makes the transaction commit hit an assertion failure at btrfs_trans_release_metadata() because ->bytes_reserved is not zero but the ->block_rsv is NULL. The produced stack trace for that is like the following: [192922.917158] assertion failed: !trans->bytes_reserved, file: fs/btrfs/transaction.c, line: 816 [192922.917553] ------------[ cut here ]------------ [192922.917922] kernel BUG at fs/btrfs/ctree.h:3532! [192922.918310] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI [192922.918666] CPU: 2 PID: 883 Comm: fsstress Tainted: G W 5.1.4-btrfs-next-47 #1 [192922.919035] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [192922.919801] RIP: 0010:assfail.constprop.25+0x18/0x1a [btrfs] (...) [192922.920925] RSP: 0018:ffffaebdc8a27da8 EFLAGS: 00010286 [192922.921315] RAX: 0000000000000051 RBX: ffff95c9c16a41c0 RCX: 0000000000000000 [192922.921692] RDX: 0000000000000000 RSI: ffff95cab6b16838 RDI: ffff95cab6b16838 [192922.922066] RBP: ffff95c9c16a41c0 R08: 0000000000000000 R09: 0000000000000000 [192922.922442] R10: ffffaebdc8a27e70 R11: 0000000000000000 R12: ffff95ca731a0980 [192922.922820] R13: 0000000000000000 R14: ffff95ca84c73338 R15: ffff95ca731a0ea8 [192922.923200] FS: 00007f337eda4e80(0000) GS:ffff95cab6b00000(0000) knlGS:0000000000000000 [192922.923579] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [192922.923948] CR2: 00007f337edad000 CR3: 00000001e00f6002 CR4: 00000000003606e0 [192922.924329] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [192922.924711] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [192922.925105] Call Trace: [192922.925505] btrfs_trans_release_metadata+0x10c/0x170 [btrfs] [192922.925911] btrfs_commit_transaction+0x3e/0xaf0 [btrfs] [192922.926324] btrfs_sync_file+0x44c/0x490 [btrfs] [192922.926731] do_fsync+0x38/0x60 [192922.927138] __x64_sys_fdatasync+0x13/0x20 [192922.927543] do_syscall_64+0x60/0x1c0 [192922.927939] entry_SYSCALL_64_after_hwframe+0x49/0xbe (...) [192922.934077] ---[ end trace f00808b12068168f ]--- 2) If evict_refill_and_join() decides to commit the transaction, it will be able to do it, since the nested transaction join only increments the transaction handle's ->use_count reference counter and it does not prevent the transaction from getting committed. This means that after eviction completes, the fsync logging path will be using a transaction handle that refers to an already committed transaction. What happens when using such a stale transaction can be unpredictable, we are at least having a use-after-free on the transaction handle itself, since the transaction commit will call kmem_cache_free() against the handle regardless of its ->use_count value, or we can end up silently losing all the updates to the log tree after that iput() in the logging path, or using a transaction handle that in the meanwhile was allocated to another task for a new transaction, etc, pretty much unpredictable what can happen. In order to fix both of them, instead of using iput() during logging, use btrfs_add_delayed_iput(), so that the logging path of fsync never drops the last reference on an inode, that step is offloaded to a safe context (usually the cleaner kthread). The assertion failure issue was sporadically triggered by the test case generic/475 from fstests, which loads the dm error target while fsstress is running, which lead to fsync failing while logging inodes with -EIO errors and then trying later to commit the transaction, triggering the assertion failure. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-16Btrfs: fix unwritten extent buffers and hangs on future writeback attemptsFilipe Manana
commit 18dfa7117a3f379862dcd3f67cadd678013bb9dd upstream. The lock_extent_buffer_io() returns 1 to the caller to tell it everything went fine and the callers needs to start writeback for the extent buffer (submit a bio, etc), 0 to tell the caller everything went fine but it does not need to start writeback for the extent buffer, and a negative value if some error happened. When it's about to return 1 it tries to lock all pages, and if a try lock on a page fails, and we didn't flush any existing bio in our "epd", it calls flush_write_bio(epd) and overwrites the return value of 1 to 0 or an error. The page might have been locked elsewhere, not with the goal of starting writeback of the extent buffer, and even by some code other than btrfs, like page migration for example, so it does not mean the writeback of the extent buffer was already started by some other task, so returning a 0 tells the caller (btree_write_cache_pages()) to not start writeback for the extent buffer. Note that epd might currently have either no bio, so flush_write_bio() returns 0 (success) or it might have a bio for another extent buffer with a lower index (logical address). Since we return 0 with the EXTENT_BUFFER_WRITEBACK bit set on the extent buffer and writeback is never started for the extent buffer, future attempts to writeback the extent buffer will hang forever waiting on that bit to be cleared, since it can only be cleared after writeback completes. Such hang is reported with a trace like the following: [49887.347053] INFO: task btrfs-transacti:1752 blocked for more than 122 seconds. [49887.347059] Not tainted 5.2.13-gentoo #2 [49887.347060] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [49887.347062] btrfs-transacti D 0 1752 2 0x80004000 [49887.347064] Call Trace: [49887.347069] ? __schedule+0x265/0x830 [49887.347071] ? bit_wait+0x50/0x50 [49887.347072] ? bit_wait+0x50/0x50 [49887.347074] schedule+0x24/0x90 [49887.347075] io_schedule+0x3c/0x60 [49887.347077] bit_wait_io+0x8/0x50 [49887.347079] __wait_on_bit+0x6c/0x80 [49887.347081] ? __lock_release.isra.29+0x155/0x2d0 [49887.347083] out_of_line_wait_on_bit+0x7b/0x80 [49887.347084] ? var_wake_function+0x20/0x20 [49887.347087] lock_extent_buffer_for_io+0x28c/0x390 [49887.347089] btree_write_cache_pages+0x18e/0x340 [49887.347091] do_writepages+0x29/0xb0 [49887.347093] ? kmem_cache_free+0x132/0x160 [49887.347095] ? convert_extent_bit+0x544/0x680 [49887.347097] filemap_fdatawrite_range+0x70/0x90 [49887.347099] btrfs_write_marked_extents+0x53/0x120 [49887.347100] btrfs_write_and_wait_transaction.isra.4+0x38/0xa0 [49887.347102] btrfs_commit_transaction+0x6bb/0x990 [49887.347103] ? start_transaction+0x33e/0x500 [49887.347105] transaction_kthread+0x139/0x15c So fix this by not overwriting the return value (ret) with the result from flush_write_bio(). We also need to clear the EXTENT_BUFFER_WRITEBACK bit in case flush_write_bio() returns an error, otherwise it will hang any future attempts to writeback the extent buffer, and undo all work done before (set back EXTENT_BUFFER_DIRTY, etc). This is a regression introduced in the 5.2 kernel. Fixes: 2e3c25136adfb ("btrfs: extent_io: add proper error handling to lock_extent_buffer_for_io()") Fixes: f4340622e0226 ("btrfs: extent_io: Move the BUG_ON() in flush_write_bio() one level up") Reported-by: Zdenek Sojka <zsojka@seznam.cz> Link: https://lore.kernel.org/linux-btrfs/GpO.2yos.3WGDOLpx6t%7D.1TUDYM@seznam.cz/T/#u Reported-by: Stefan Priebe - Profihost AG <s.priebe@profihost.ag> Link: https://lore.kernel.org/linux-btrfs/5c4688ac-10a7-fb07-70e8-c5d31a3fbb38@profihost.ag/T/#t Reported-by: Drazen Kacar <drazen.kacar@oradian.com> Link: https://lore.kernel.org/linux-btrfs/DB8PR03MB562876ECE2319B3E579590F799C80@DB8PR03MB5628.eurprd03.prod.outlook.com/ Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204377 Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-06btrfs: trim: Check the range passed into to prevent overflowQu Wenruo
[ Upstream commit 07301df7d2fc220d3de5f7ad804dcb941400cb00 ] Normally the range->len is set to default value (U64_MAX), but when it's not default value, we should check if the range overflows. And if it overflows, return -EINVAL before doing anything. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-25Btrfs: fix deadlock between fiemap and transaction commitsFilipe Manana
[ Upstream commit a6d155d2e363f26290ffd50591169cb96c2a609e ] The fiemap handler locks a file range that can have unflushed delalloc, and after locking the range, it tries to attach to a running transaction. If the running transaction started its commit, that is, it is in state TRANS_STATE_COMMIT_START, and either the filesystem was mounted with the flushoncommit option or the transaction is creating a snapshot for the subvolume that contains the file that fiemap is operating on, we end up deadlocking. This happens because fiemap is blocked on the transaction, waiting for it to complete, and the transaction is waiting for the flushed dealloc to complete, which requires locking the file range that the fiemap task already locked. The following stack traces serve as an example of when this deadlock happens: (...) [404571.515510] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs] [404571.515956] Call Trace: [404571.516360] ? __schedule+0x3ae/0x7b0 [404571.516730] schedule+0x3a/0xb0 [404571.517104] lock_extent_bits+0x1ec/0x2a0 [btrfs] [404571.517465] ? remove_wait_queue+0x60/0x60 [404571.517832] btrfs_finish_ordered_io+0x292/0x800 [btrfs] [404571.518202] normal_work_helper+0xea/0x530 [btrfs] [404571.518566] process_one_work+0x21e/0x5c0 [404571.518990] worker_thread+0x4f/0x3b0 [404571.519413] ? process_one_work+0x5c0/0x5c0 [404571.519829] kthread+0x103/0x140 [404571.520191] ? kthread_create_worker_on_cpu+0x70/0x70 [404571.520565] ret_from_fork+0x3a/0x50 [404571.520915] kworker/u8:6 D 0 31651 2 0x80004000 [404571.521290] Workqueue: btrfs-flush_delalloc btrfs_flush_delalloc_helper [btrfs] (...) [404571.537000] fsstress D 0 13117 13115 0x00004000 [404571.537263] Call Trace: [404571.537524] ? __schedule+0x3ae/0x7b0 [404571.537788] schedule+0x3a/0xb0 [404571.538066] wait_current_trans+0xc8/0x100 [btrfs] [404571.538349] ? remove_wait_queue+0x60/0x60 [404571.538680] start_transaction+0x33c/0x500 [btrfs] [404571.539076] btrfs_check_shared+0xa3/0x1f0 [btrfs] [404571.539513] ? extent_fiemap+0x2ce/0x650 [btrfs] [404571.539866] extent_fiemap+0x2ce/0x650 [btrfs] [404571.540170] do_vfs_ioctl+0x526/0x6f0 [404571.540436] ksys_ioctl+0x70/0x80 [404571.540734] __x64_sys_ioctl+0x16/0x20 [404571.540997] do_syscall_64+0x60/0x1d0 [404571.541279] entry_SYSCALL_64_after_hwframe+0x49/0xbe (...) [404571.543729] btrfs D 0 14210 14208 0x00004000 [404571.544023] Call Trace: [404571.544275] ? __schedule+0x3ae/0x7b0 [404571.544526] ? wait_for_completion+0x112/0x1a0 [404571.544795] schedule+0x3a/0xb0 [404571.545064] schedule_timeout+0x1ff/0x390 [404571.545351] ? lock_acquire+0xa6/0x190 [404571.545638] ? wait_for_completion+0x49/0x1a0 [404571.545890] ? wait_for_completion+0x112/0x1a0 [404571.546228] wait_for_completion+0x131/0x1a0 [404571.546503] ? wake_up_q+0x70/0x70 [404571.546775] btrfs_wait_ordered_extents+0x27c/0x400 [btrfs] [404571.547159] btrfs_commit_transaction+0x3b0/0xae0 [btrfs] [404571.547449] ? btrfs_mksubvol+0x4a4/0x640 [btrfs] [404571.547703] ? remove_wait_queue+0x60/0x60 [404571.547969] btrfs_mksubvol+0x605/0x640 [btrfs] [404571.548226] ? __sb_start_write+0xd4/0x1c0 [404571.548512] ? mnt_want_write_file+0x24/0x50 [404571.548789] btrfs_ioctl_snap_create_transid+0x169/0x1a0 [btrfs] [404571.549048] btrfs_ioctl_snap_create_v2+0x11d/0x170 [btrfs] [404571.549307] btrfs_ioctl+0x133f/0x3150 [btrfs] [404571.549549] ? mem_cgroup_charge_statistics+0x4c/0xd0 [404571.549792] ? mem_cgroup_commit_charge+0x84/0x4b0 [404571.550064] ? __handle_mm_fault+0xe3e/0x11f0 [404571.550306] ? do_raw_spin_unlock+0x49/0xc0 [404571.550608] ? _raw_spin_unlock+0x24/0x30 [404571.550976] ? __handle_mm_fault+0xedf/0x11f0 [404571.551319] ? do_vfs_ioctl+0xa2/0x6f0 [404571.551659] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [404571.552087] do_vfs_ioctl+0xa2/0x6f0 [404571.552355] ksys_ioctl+0x70/0x80 [404571.552621] __x64_sys_ioctl+0x16/0x20 [404571.552864] do_syscall_64+0x60/0x1d0 [404571.553104] entry_SYSCALL_64_after_hwframe+0x49/0xbe (...) If we were joining the transaction instead of attaching to it, we would not risk a deadlock because a join only blocks if the transaction is in a state greater then or equals to TRANS_STATE_COMMIT_DOING, and the delalloc flush performed by a transaction is done before it reaches that state, when it is in the state TRANS_STATE_COMMIT_START. However a transaction join is intended for use cases where we do modify the filesystem, and fiemap only needs to peek at delayed references from the current transaction in order to determine if extents are shared, and, besides that, when there is no current transaction or when it blocks to wait for a current committing transaction to complete, it creates a new transaction without reserving any space. Such unnecessary transactions, besides doing unnecessary IO, can cause transaction aborts (-ENOSPC) and unnecessary rotation of the precious backup roots. So fix this by adding a new transaction join variant, named join_nostart, which behaves like the regular join, but it does not create a transaction when none currently exists or after waiting for a committing transaction to complete. Fixes: 03628cdbc64db6 ("Btrfs: do not start a transaction during fiemap") Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-06Btrfs: fix race leading to fs corruption after transaction abortFilipe Manana
commit cb2d3daddbfb6318d170e79aac1f7d5e4d49f0d7 upstream. When one transaction is finishing its commit, it is possible for another transaction to start and enter its initial commit phase as well. If the first ends up getting aborted, we have a small time window where the second transaction commit does not notice that the previous transaction aborted and ends up committing, writing a superblock that points to btrees that reference extent buffers (nodes and leafs) that were not persisted to disk. The consequence is that after mounting the filesystem again, we will be unable to load some btree nodes/leafs, either because the content on disk is either garbage (or just zeroes) or corresponds to the old content of a previouly COWed or deleted node/leaf, resulting in the well known error messages "parent transid verify failed on ...". The following sequence diagram illustrates how this can happen. CPU 1 CPU 2 <at transaction N> btrfs_commit_transaction() (...) --> sets transaction state to TRANS_STATE_UNBLOCKED --> sets fs_info->running_transaction to NULL (...) btrfs_start_transaction() start_transaction() wait_current_trans() --> returns immediately because fs_info->running_transaction is NULL join_transaction() --> creates transaction N + 1 --> sets fs_info->running_transaction to transaction N + 1 --> adds transaction N + 1 to the fs_info->trans_list list --> returns transaction handle pointing to the new transaction N + 1 (...) btrfs_sync_file() btrfs_start_transaction() --> returns handle to transaction N + 1 (...) btrfs_write_and_wait_transaction() --> writeback of some extent buffer fails, returns an error btrfs_handle_fs_error() --> sets BTRFS_FS_STATE_ERROR in fs_info->fs_state --> jumps to label "scrub_continue" cleanup_transaction() btrfs_abort_transaction(N) --> sets BTRFS_FS_STATE_TRANS_ABORTED flag in fs_info->fs_state --> sets aborted field in the transaction and transaction handle structures, for transaction N only --> removes transaction from the list fs_info->trans_list btrfs_commit_transaction(N + 1) --> transaction N + 1 was not aborted, so it proceeds (...) --> sets the transaction's state to TRANS_STATE_COMMIT_START --> does not find the previous transaction (N) in the fs_info->trans_list, so it doesn't know that transaction was aborted, and the commit of transaction N + 1 proceeds (...) --> sets transaction N + 1 state to TRANS_STATE_UNBLOCKED btrfs_write_and_wait_transaction() --> succeeds writing all extent buffers created in the transaction N + 1 write_all_supers() --> succeeds --> we now have a superblock on disk that points to trees that refer to at least one extent buffer that was never persisted So fix this by updating the transaction commit path to check if the flag BTRFS_FS_STATE_TRANS_ABORTED is set on fs_info->fs_state if after setting the transaction to the TRANS_STATE_COMMIT_START we do not find any previous transaction in the fs_info->trans_list. If the flag is set, just fail the transaction commit with -EROFS, as we do in other places. The exact error code for the previous transaction abort was already logged and reported. Fixes: 49b25e0540904b ("btrfs: enhance transaction abort infrastructure") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-06Btrfs: fix incremental send failure after deduplicationFilipe Manana
commit b4f9a1a87a48c255bb90d8a6c3d555a1abb88130 upstream. When doing an incremental send operation we can fail if we previously did deduplication operations against a file that exists in both snapshots. In that case we will fail the send operation with -EIO and print a message to dmesg/syslog like the following: BTRFS error (device sdc): Send: inconsistent snapshot, found updated \ extent for inode 257 without updated inode item, send root is 258, \ parent root is 257 This requires that we deduplicate to the same file in both snapshots for the same amount of times on each snapshot. The issue happens because a deduplication only updates the iversion of an inode and does not update any other field of the inode, therefore if we deduplicate the file on each snapshot for the same amount of time, the inode will have the same iversion value (stored as the "sequence" field on the inode item) on both snapshots, therefore it will be seen as unchanged between in the send snapshot while there are new/updated/deleted extent items when comparing to the parent snapshot. This makes the send operation return -EIO and print an error message. Example reproducer: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt # Create our first file. The first half of the file has several 64Kb # extents while the second half as a single 512Kb extent. $ xfs_io -f -s -c "pwrite -S 0xb8 -b 64K 0 512K" /mnt/foo $ xfs_io -c "pwrite -S 0xb8 512K 512K" /mnt/foo # Create the base snapshot and the parent send stream from it. $ btrfs subvolume snapshot -r /mnt /mnt/mysnap1 $ btrfs send -f /tmp/1.snap /mnt/mysnap1 # Create our second file, that has exactly the same data as the first # file. $ xfs_io -f -c "pwrite -S 0xb8 0 1M" /mnt/bar # Create the second snapshot, used for the incremental send, before # doing the file deduplication. $ btrfs subvolume snapshot -r /mnt /mnt/mysnap2 # Now before creating the incremental send stream: # # 1) Deduplicate into a subrange of file foo in snapshot mysnap1. This # will drop several extent items and add a new one, also updating # the inode's iversion (sequence field in inode item) by 1, but not # any other field of the inode; # # 2) Deduplicate into a different subrange of file foo in snapshot # mysnap2. This will replace an extent item with a new one, also # updating the inode's iversion by 1 but not any other field of the # inode. # # After these two deduplication operations, the inode items, for file # foo, are identical in both snapshots, but we have different extent # items for this inode in both snapshots. We want to check this doesn't # cause send to fail with an error or produce an incorrect stream. $ xfs_io -r -c "dedupe /mnt/bar 0 0 512K" /mnt/mysnap1/foo $ xfs_io -r -c "dedupe /mnt/bar 512K 512K 512K" /mnt/mysnap2/foo # Create the incremental send stream. $ btrfs send -p /mnt/mysnap1 -f /tmp/2.snap /mnt/mysnap2 ERROR: send ioctl failed with -5: Input/output error This issue started happening back in 2015 when deduplication was updated to not update the inode's ctime and mtime and update only the iversion. Back then we would hit a BUG_ON() in send, but later in 2016 send was updated to return -EIO and print the error message instead of doing the BUG_ON(). A test case for fstests follows soon. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203933 Fixes: 1c919a5e13702c ("btrfs: don't update mtime/ctime on deduped inodes") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-06btrfs: qgroup: Don't hold qgroup_ioctl_lock in btrfs_qgroup_inherit()Qu Wenruo
[ Upstream commit e88439debd0a7f969b3ddba6f147152cd0732676 ] [BUG] Lockdep will report the following circular locking dependency: WARNING: possible circular locking dependency detected 5.2.0-rc2-custom #24 Tainted: G O ------------------------------------------------------ btrfs/8631 is trying to acquire lock: 000000002536438c (&fs_info->qgroup_ioctl_lock#2){+.+.}, at: btrfs_qgroup_inherit+0x40/0x620 [btrfs] but task is already holding lock: 000000003d52cc23 (&fs_info->tree_log_mutex){+.+.}, at: create_pending_snapshot+0x8b6/0xe60 [btrfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&fs_info->tree_log_mutex){+.+.}: __mutex_lock+0x76/0x940 mutex_lock_nested+0x1b/0x20 btrfs_commit_transaction+0x475/0xa00 [btrfs] btrfs_commit_super+0x71/0x80 [btrfs] close_ctree+0x2bd/0x320 [btrfs] btrfs_put_super+0x15/0x20 [btrfs] generic_shutdown_super+0x72/0x110 kill_anon_super+0x18/0x30 btrfs_kill_super+0x16/0xa0 [btrfs] deactivate_locked_super+0x3a/0x80 deactivate_super+0x51/0x60 cleanup_mnt+0x3f/0x80 __cleanup_mnt+0x12/0x20 task_work_run+0x94/0xb0 exit_to_usermode_loop+0xd8/0xe0 do_syscall_64+0x210/0x240 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (&fs_info->reloc_mutex){+.+.}: __mutex_lock+0x76/0x940 mutex_lock_nested+0x1b/0x20 btrfs_commit_transaction+0x40d/0xa00 [btrfs] btrfs_quota_enable+0x2da/0x730 [btrfs] btrfs_ioctl+0x2691/0x2b40 [btrfs] do_vfs_ioctl+0xa9/0x6d0 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x65/0x240 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&fs_info->qgroup_ioctl_lock#2){+.+.}: lock_acquire+0xa7/0x190 __mutex_lock+0x76/0x940 mutex_lock_nested+0x1b/0x20 btrfs_qgroup_inherit+0x40/0x620 [btrfs] create_pending_snapshot+0x9d7/0xe60 [btrfs] create_pending_snapshots+0x94/0xb0 [btrfs] btrfs_commit_transaction+0x415/0xa00 [btrfs] btrfs_mksubvol+0x496/0x4e0 [btrfs] btrfs_ioctl_snap_create_transid+0x174/0x180 [btrfs] btrfs_ioctl_snap_create_v2+0x11c/0x180 [btrfs] btrfs_ioctl+0xa90/0x2b40 [btrfs] do_vfs_ioctl+0xa9/0x6d0 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x65/0x240 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: &fs_info->qgroup_ioctl_lock#2 --> &fs_info->reloc_mutex --> &fs_info->tree_log_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_info->tree_log_mutex); lock(&fs_info->reloc_mutex); lock(&fs_info->tree_log_mutex); lock(&fs_info->qgroup_ioctl_lock#2); *** DEADLOCK *** 6 locks held by btrfs/8631: #0: 00000000ed8f23f6 (sb_writers#12){.+.+}, at: mnt_want_write_file+0x28/0x60 #1: 000000009fb1597a (&type->i_mutex_dir_key#10/1){+.+.}, at: btrfs_mksubvol+0x70/0x4e0 [btrfs] #2: 0000000088c5ad88 (&fs_info->subvol_sem){++++}, at: btrfs_mksubvol+0x128/0x4e0 [btrfs] #3: 000000009606fc3e (sb_internal#2){.+.+}, at: start_transaction+0x37a/0x520 [btrfs] #4: 00000000f82bbdf5 (&fs_info->reloc_mutex){+.+.}, at: btrfs_commit_transaction+0x40d/0xa00 [btrfs] #5: 000000003d52cc23 (&fs_info->tree_log_mutex){+.+.}, at: create_pending_snapshot+0x8b6/0xe60 [btrfs] [CAUSE] Due to the delayed subvolume creation, we need to call btrfs_qgroup_inherit() inside commit transaction code, with a lot of other mutex hold. This hell of lock chain can lead to above problem. [FIX] On the other hand, we don't really need to hold qgroup_ioctl_lock if we're in the context of create_pending_snapshot(). As in that context, we're the only one being able to modify qgroup. All other qgroup functions which needs qgroup_ioctl_lock are either holding a transaction handle, or will start a new transaction: Functions will start a new transaction(): * btrfs_quota_enable() * btrfs_quota_disable() Functions hold a transaction handler: * btrfs_add_qgroup_relation() * btrfs_del_qgroup_relation() * btrfs_create_qgroup() * btrfs_remove_qgroup() * btrfs_limit_qgroup() * btrfs_qgroup_inherit() call inside create_subvol() So we have a higher level protection provided by transaction, thus we don't need to always hold qgroup_ioctl_lock in btrfs_qgroup_inherit(). Only the btrfs_qgroup_inherit() call in create_subvol() needs to hold qgroup_ioctl_lock, while the btrfs_qgroup_inherit() call in create_pending_snapshot() is already protected by transaction. So the fix is to detect the context by checking trans->transaction->state. If we're at TRANS_STATE_COMMIT_DOING, then we're in commit transaction context and no need to get the mutex. Reported-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-06btrfs: Flush before reflinking any extent to prevent NOCOW write falling ↵Qu Wenruo
back to COW without data reservation [ Upstream commit a94d1d0cb3bf1983fcdf05b59d914dbff4f1f52c ] [BUG] The following script can cause unexpected fsync failure: #!/bin/bash dev=/dev/test/test mnt=/mnt/btrfs mkfs.btrfs -f $dev -b 512M > /dev/null mount $dev $mnt -o nospace_cache # Prealloc one extent xfs_io -f -c "falloc 8k 64m" $mnt/file1 # Fill the remaining data space xfs_io -f -c "pwrite 0 -b 4k 512M" $mnt/padding sync # Write into the prealloc extent xfs_io -c "pwrite 1m 16m" $mnt/file1 # Reflink then fsync, fsync would fail due to ENOSPC xfs_io -c "reflink $mnt/file1 8k 0 4k" -c "fsync" $mnt/file1 umount $dev The fsync fails with ENOSPC, and the last page of the buffered write is lost. [CAUSE] This is caused by: - Btrfs' back reference only has extent level granularity So write into shared extent must be COWed even only part of the extent is shared. So for above script we have: - fallocate Create a preallocated extent where we can do NOCOW write. - fill all the remaining data and unallocated space - buffered write into preallocated space As we have not enough space available for data and the extent is not shared (yet) we fall into NOCOW mode. - reflink Now part of the large preallocated extent is shared, later write into that extent must be COWed. - fsync triggers writeback But now the extent is shared and therefore we must fallback into COW mode, which fails with ENOSPC since there's not enough space to allocate data extents. [WORKAROUND] The workaround is to ensure any buffered write in the related extents (not just the reflink source range) get flushed before reflink/dedupe, so that NOCOW writes succeed that happened before reflinking succeed. The workaround is expensive, we could do it better by only flushing NOCOW range, but that needs extra accounting for NOCOW range. For now, fix the possible data loss first. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-06btrfs: fix minimum number of chunk errors for DUPDavid Sterba
[ Upstream commit 0ee5f8ae082e1f675a2fb6db601c31ac9958a134 ] The list of profiles in btrfs_chunk_max_errors lists DUP as a profile DUP able to tolerate 1 device missing. Though this profile is special with 2 copies, it still needs the device, unlike the others. Looking at the history of changes, thre's no clear reason why DUP is there, functions were refactored and blocks of code merged to one helper. d20983b40e828 Btrfs: fix writing data into the seed filesystem - factor code to a helper de11cc12df173 Btrfs: don't pre-allocate btrfs bio - unrelated change, DUP still in the list with max errors 1 a236aed14ccb0 Btrfs: Deal with failed writes in mirrored configurations - introduced the max errors, leaves DUP and RAID1 in the same group Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-06btrfs: tree-checker: Check if the file extent end overflowsQu Wenruo
[ Upstream commit 4c094c33c9ed4b8d0d814bd1d7ff78e123d15d00 ] Under certain conditions, we could have strange file extent item in log tree like: item 18 key (69599 108 397312) itemoff 15208 itemsize 53 extent data disk bytenr 0 nr 0 extent data offset 0 nr 18446744073709547520 ram 18446744073709547520 The num_bytes + ram_bytes overflow 64 bit type. For num_bytes part, we can detect such overflow along with file offset (key->offset), as file_offset + num_bytes should never go beyond u64. For ram_bytes part, it's about the decompressed size of the extent, not directly related to the size. In theory it is OK to have a large value, and put extra limitation on RAM bytes may cause unexpected false alerts. So in tree-checker, we only check if the file offset and num bytes overflow. Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31btrfs: inode: Don't compress if NODATASUM or NODATACOW setQu Wenruo
commit 42c16da6d684391db83788eb680accd84f6c2083 upstream. As btrfs(5) specified: Note If nodatacow or nodatasum are enabled, compression is disabled. If NODATASUM or NODATACOW set, we should not compress the extent. Normally NODATACOW is detected properly in run_delalloc_range() so compression won't happen for NODATACOW. However for NODATASUM we don't have any check, and it can cause compressed extent without csum pretty easily, just by: mkfs.btrfs -f $dev mount $dev $mnt -o nodatasum touch $mnt/foobar mount -o remount,datasum,compress $mnt xfs_io -f -c "pwrite 0 128K" $mnt/foobar And in fact, we have a bug report about corrupted compressed extent without proper data checksum so even RAID1 can't recover the corruption. (https://bugzilla.kernel.org/show_bug.cgi?id=199707) Running compression without proper checksum could cause more damage when corruption happens, as compressed data could make the whole extent unreadable, so there is no need to allow compression for NODATACSUM. The fix will refactor the inode compression check into two parts: - inode_can_compress() As the hard requirement, checked at btrfs_run_delalloc_range(), so no compression will happen for NODATASUM inode at all. - inode_need_compress() As the soft requirement, checked at btrfs_run_delalloc_range() and compress_file_range(). Reported-by: James Harvey <jamespharvey20@gmail.com> CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-31btrfs: shut up bogus -Wmaybe-uninitialized warningArnd Bergmann
commit 6c64460cdc8be5fa074aa8fe2ae8736d5792bdc5 upstream. gcc sometimes can't determine whether a variable has been initialized when both the initialization and the use are conditional: fs/btrfs/props.c: In function 'inherit_props': fs/btrfs/props.c:389:4: error: 'num_bytes' may be used uninitialized in this function [-Werror=maybe-uninitialized] btrfs_block_rsv_release(fs_info, trans->block_rsv, This code is fine. Unfortunately, I cannot think of a good way to rephrase it in a way that makes gcc understand this, so I add a bogus initialization the way one should not. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: David Sterba <dsterba@suse.com> [ gcc 8 and 9 don't emit the warning ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-26Btrfs: add missing inode version, ctime and mtime updates when punching holeFilipe Manana
commit 179006688a7e888cbff39577189f2e034786d06a upstream. If the range for which we are punching a hole covers only part of a page, we end up updating the inode item but we skip the update of the inode's iversion, mtime and ctime. Fix that by ensuring we update those properties of the inode. A patch for fstests test case generic/059 that tests this as been sent along with this fix. Fixes: 2aaa66558172b0 ("Btrfs: add hole punching") Fixes: e8c1c76e804b18 ("Btrfs: add missing inode update when punching hole") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-26Btrfs: fix fsync not persisting dentry deletions due to inode evictionsFilipe Manana
commit 803f0f64d17769071d7287d9e3e3b79a3e1ae937 upstream. In order to avoid searches on a log tree when unlinking an inode, we check if the inode being unlinked was logged in the current transaction, as well as the inode of its parent directory. When any of the inodes are logged, we proceed to delete directory items and inode reference items from the log, to ensure that if a subsequent fsync of only the inode being unlinked or only of the parent directory when the other is not fsync'ed as well, does not result in the entry still existing after a power failure. That check however is not reliable when one of the inodes involved (the one being unlinked or its parent directory's inode) is evicted, since the logged_trans field is transient, that is, it is not stored on disk, so it is lost when the inode is evicted and loaded into memory again (which is set to zero on load). As a consequence the checks currently being done by btrfs_del_dir_entries_in_log() and btrfs_del_inode_ref_in_log() always return true if the inode was evicted before, regardless of the inode having been logged or not before (and in the current transaction), this results in the dentry being unlinked still existing after a log replay if after the unlink operation only one of the inodes involved is fsync'ed. Example: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ mkdir /mnt/dir $ touch /mnt/dir/foo $ xfs_io -c fsync /mnt/dir/foo # Keep an open file descriptor on our directory while we evict inodes. # We just want to evict the file's inode, the directory's inode must not # be evicted. $ ( cd /mnt/dir; while true; do :; done ) & $ pid=$! # Wait a bit to give time to background process to chdir to our test # directory. $ sleep 0.5 # Trigger eviction of the file's inode. $ echo 2 > /proc/sys/vm/drop_caches # Unlink our file and fsync the parent directory. After a power failure # we don't expect to see the file anymore, since we fsync'ed the parent # directory. $ rm -f $SCRATCH_MNT/dir/foo $ xfs_io -c fsync /mnt/dir <power failure> $ mount /dev/sdb /mnt $ ls /mnt/dir foo $ --> file still there, unlink not persisted despite explicit fsync on dir Fix this by checking if the inode has the full_sync bit set in its runtime flags as well, since that bit is set everytime an inode is loaded from disk, or for other less common cases such as after a shrinking truncate or failure to allocate extent maps for holes, and gets cleared after the first fsync. Also consider the inode as possibly logged only if it was last modified in the current transaction (besides having the full_fsync flag set). Fixes: 3a5f1d458ad161 ("Btrfs: Optimize btree walking while logging inodes") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-26Btrfs: fix data loss after inode eviction, renaming it, and fsync itFilipe Manana
commit d1d832a0b51dd9570429bb4b81b2a6c1759e681a upstream. When we log an inode, regardless of logging it completely or only that it exists, we always update it as logged (logged_trans and last_log_commit fields of the inode are updated). This is generally fine and avoids future attempts to log it from having to do repeated work that brings no value. However, if we write data to a file, then evict its inode after all the dealloc was flushed (and ordered extents completed), rename the file and fsync it, we end up not logging the new extents, since the rename may result in logging that the inode exists in case the parent directory was logged before. The following reproducer shows and explains how this can happen: $ mkfs.btrfs -f /dev/sdb $ mount /dev/sdb /mnt $ mkdir /mnt/dir $ touch /mnt/dir/foo $ touch /mnt/dir/bar # Do a direct IO write instead of a buffered write because with a # buffered write we would need to make sure dealloc gets flushed and # complete before we do the inode eviction later, and we can not do that # from user space with call to things such as sync(2) since that results # in a transaction commit as well. $ xfs_io -d -c "pwrite -S 0xd3 0 4K" /mnt/dir/bar # Keep the directory dir in use while we evict inodes. We want our file # bar's inode to be evicted but we don't want our directory's inode to # be evicted (if it were evicted too, we would not be able to reproduce # the issue since the first fsync below, of file foo, would result in a # transaction commit. $ ( cd /mnt/dir; while true; do :; done ) & $ pid=$! # Wait a bit to give time for the background process to chdir. $ sleep 0.1 # Evict all inodes, except the inode for the directory dir because it is # currently in use by our background process. $ echo 2 > /proc/sys/vm/drop_caches # fsync file foo, which ends up persisting information about the parent # directory because it is a new inode. $ xfs_io -c fsync /mnt/dir/foo # Rename bar, this results in logging that this inode exists (inode item, # names, xattrs) because the parent directory is in the log. $ mv /mnt/dir/bar /mnt/dir/baz # Now fsync baz, which ends up doing absolutely nothing because of the # rename operation which logged that the inode exists only. $ xfs_io -c fsync /mnt/dir/baz <power failure> $ mount /dev/sdb /mnt $ od -t x1 -A d /mnt/dir/baz 0000000 --> Empty file, data we wrote is missing. Fix this by not updating last_sub_trans of an inode when we are logging only that it exists and the inode was not yet logged since it was loaded from disk (full_sync bit set), this is enough to make btrfs_inode_in_log() return false for this scenario and make us log the inode. The logged_trans of the inode is still always setsince that alone is used to track if names need to be deleted as part of unlink operations. Fixes: 257c62e1bce03e ("Btrfs: avoid tree log commit when there are no changes") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-26btrfs: correctly validate compression typeJohannes Thumshirn
commit aa53e3bfac7205fb3a8815ac1c937fd6ed01b41e upstream. Nikolay reported the following KASAN splat when running btrfs/048: [ 1843.470920] ================================================================== [ 1843.471971] BUG: KASAN: slab-out-of-bounds in strncmp+0x66/0xb0 [ 1843.472775] Read of size 1 at addr ffff888111e369e2 by task btrfs/3979 [ 1843.473904] CPU: 3 PID: 3979 Comm: btrfs Not tainted 5.2.0-rc3-default #536 [ 1843.475009] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 1843.476322] Call Trace: [ 1843.476674] dump_stack+0x7c/0xbb [ 1843.477132] ? strncmp+0x66/0xb0 [ 1843.477587] print_address_description+0x114/0x320 [ 1843.478256] ? strncmp+0x66/0xb0 [ 1843.478740] ? strncmp+0x66/0xb0 [ 1843.479185] __kasan_report+0x14e/0x192 [ 1843.479759] ? strncmp+0x66/0xb0 [ 1843.480209] kasan_report+0xe/0x20 [ 1843.480679] strncmp+0x66/0xb0 [ 1843.481105] prop_compression_validate+0x24/0x70 [ 1843.481798] btrfs_xattr_handler_set_prop+0x65/0x160 [ 1843.482509] __vfs_setxattr+0x71/0x90 [ 1843.483012] __vfs_setxattr_noperm+0x84/0x130 [ 1843.483606] vfs_setxattr+0xac/0xb0 [ 1843.484085] setxattr+0x18c/0x230 [ 1843.484546] ? vfs_setxattr+0xb0/0xb0 [ 1843.485048] ? __mod_node_page_state+0x1f/0xa0 [ 1843.485672] ? _raw_spin_unlock+0x24/0x40 [ 1843.486233] ? __handle_mm_fault+0x988/0x1290 [ 1843.486823] ? lock_acquire+0xb4/0x1e0 [ 1843.487330] ? lock_acquire+0xb4/0x1e0 [ 1843.487842] ? mnt_want_write_file+0x3c/0x80 [ 1843.488442] ? debug_lockdep_rcu_enabled+0x22/0x40 [ 1843.489089] ? rcu_sync_lockdep_assert+0xe/0x70 [ 1843.489707] ? __sb_start_write+0x158/0x200 [ 1843.490278] ? mnt_want_write_file+0x3c/0x80 [ 1843.490855] ? __mnt_want_write+0x98/0xe0 [ 1843.491397] __x64_sys_fsetxattr+0xba/0xe0 [ 1843.492201] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 1843.493201] do_syscall_64+0x6c/0x230 [ 1843.493988] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 1843.495041] RIP: 0033:0x7fa7a8a7707a [ 1843.495819] Code: 48 8b 0d 21 de 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 be 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d ee dd 2b 00 f7 d8 64 89 01 48 [ 1843.499203] RSP: 002b:00007ffcb73bca38 EFLAGS: 00000202 ORIG_RAX: 00000000000000be [ 1843.500210] RAX: ffffffffffffffda RBX: 00007ffcb73bda9d RCX: 00007fa7a8a7707a [ 1843.501170] RDX: 00007ffcb73bda9d RSI: 00000000006dc050 RDI: 0000000000000003 [ 1843.502152] RBP: 00000000006dc050 R08: 0000000000000000 R09: 0000000000000000 [ 1843.503109] R10: 0000000000000002 R11: 0000000000000202 R12: 00007ffcb73bda91 [ 1843.504055] R13: 0000000000000003 R14: 00007ffcb73bda82 R15: ffffffffffffffff [ 1843.505268] Allocated by task 3979: [ 1843.505771] save_stack+0x19/0x80 [ 1843.506211] __kasan_kmalloc.constprop.5+0xa0/0xd0 [ 1843.506836] setxattr+0xeb/0x230 [ 1843.507264] __x64_sys_fsetxattr+0xba/0xe0 [ 1843.507886] do_syscall_64+0x6c/0x230 [ 1843.508429] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 1843.509558] Freed by task 0: [ 1843.510188] (stack is not available) [ 1843.511309] The buggy address belongs to the object at ffff888111e369e0 which belongs to the cache kmalloc-8 of size 8 [ 1843.514095] The buggy address is located 2 bytes inside of 8-byte region [ffff888111e369e0, ffff888111e369e8) [ 1843.516524] The buggy address belongs to the page: [ 1843.517561] page:ffff88813f478d80 refcount:1 mapcount:0 mapping:ffff88811940c300 index:0xffff888111e373b8 compound_mapcount: 0 [ 1843.519993] flags: 0x4404000010200(slab|head) [ 1843.520951] raw: 0004404000010200 ffff88813f48b008 ffff888119403d50 ffff88811940c300 [ 1843.522616] raw: ffff888111e373b8 000000000016000f 00000001ffffffff 0000000000000000 [ 1843.524281] page dumped because: kasan: bad access detected [ 1843.525936] Memory state around the buggy address: [ 1843.526975] ffff888111e36880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 1843.528479] ffff888111e36900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 1843.530138] >ffff888111e36980: fc fc fc fc fc fc fc fc fc fc fc fc 02 fc fc fc [ 1843.531877] ^ [ 1843.533287] ffff888111e36a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 1843.534874] ffff888111e36a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 1843.536468] ================================================================== This is caused by supplying a too short compression value ('lz') in the test-case and comparing it to 'lzo' with strncmp() and a length of 3. strncmp() read past the 'lz' when looking for the 'o' and thus caused an out-of-bounds read. Introduce a new check 'btrfs_compress_is_valid_type()' which not only checks the user-supplied value against known compression types, but also employs checks for too short values. Reported-by: Nikolay Borisov <nborisov@suse.com> Fixes: 272e5326c783 ("btrfs: prop: fix vanished compression property after failed set") CC: stable@vger.kernel.org # 5.1+ Reviewed-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-18Merge tag 'for-5.2-rc5-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - regression where properties stored as xattrs are not properly persisted - a small readahead fix (the fstests testcase for that fix hangs on unpatched kernel, so we'd like get it merged to ease future testing) - fix a race during block group creation and deletion * tag 'for-5.2-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: Btrfs: fix failure to persist compression property xattr deletion on fsync btrfs: start readahead also in seed devices Btrfs: fix race between block group removal and block group allocation
2019-06-17Btrfs: fix failure to persist compression property xattr deletion on fsyncFilipe Manana
After the recent series of cleanups in the properties and xattrs modules that landed in the 5.2 merge window, we ended up with a regression where after deleting the compression xattr property through the setflags ioctl, we don't set the BTRFS_INODE_COPY_EVERYTHING flag in the inode anymore. As a consequence, if the inode was fsync'ed when it had the compression property set, after deleting the compression property through the setflags ioctl and fsync'ing again the inode, the log will still contain the compression xattr, because the inode did not had that bit set, which made the fsync not delete all xattrs from the log and copy all xattrs from the subvolume tree to the log tree. This regression happens due to the fact that that series of cleanups made btrfs_set_prop() call the old function do_setxattr() (which is now named btrfs_setxattr()), and not the old version of btrfs_setxattr(), which is now called btrfs_setxattr_trans(). Fix this by setting the BTRFS_INODE_COPY_EVERYTHING bit in the current btrfs_setxattr() function and remove it from everywhere else, including its setup at btrfs_ioctl_setflags(). This is cleaner, avoids similar regressions in the future, and centralizes the setup of the bit. After all, the need to setup this bit should only be in the xattrs module, since it is an implementation of xattrs. Fixes: 04e6863b19c722 ("btrfs: split btrfs_setxattr calls regarding transaction") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2019-06-14btrfs: start readahead also in seed devicesNaohiro Aota
Currently, btrfs does not consult seed devices to start readahead. As a result, if readahead zone is added to the seed devices, btrfs_reada_wait() indefinitely wait for the reada_ctl to finish. You can reproduce the hung by modifying btrfs/163 to have larger initial file size (e.g. xfs_io pwrite 4M instead of current 256K). Fixes: 7414a03fbf9e ("btrfs: initial readahead code and prototypes") Cc: stable@vger.kernel.org # 3.2+: ce7791ffee1e: Btrfs: fix race between readahead and device replace/removal Cc: stable@vger.kernel.org # 3.2+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2019-06-12Btrfs: fix race between block group removal and block group allocationFilipe Manana
If a task is removing the block group that currently has the highest start offset amongst all existing block groups, there is a short time window where it races with a concurrent block group allocation, resulting in a transaction abort with an error code of EEXIST. The following diagram explains the race in detail: Task A Task B btrfs_remove_block_group(bg offset X) remove_extent_mapping(em offset X) -> removes extent map X from the tree of extent maps (fs_info->mapping_tree), so the next call to find_next_chunk() will return offset X btrfs_alloc_chunk() find_next_chunk() --> returns offset X __btrfs_alloc_chunk(offset X) btrfs_make_block_group() btrfs_create_block_group_cache() --> creates btrfs_block_group_cache object with a key corresponding to the block group item in the extent, the key is: (offset X, BTRFS_BLOCK_GROUP_ITEM_KEY, 1G) --> adds the btrfs_block_group_cache object to the list new_bgs of the transaction handle btrfs_end_transaction(trans handle) __btrfs_end_transaction() btrfs_create_pending_block_groups() --> sees the new btrfs_block_group_cache in the new_bgs list of the transaction handle --> its call to btrfs_insert_item() fails with -EEXIST when attempting to insert the block group item key (offset X, BTRFS_BLOCK_GROUP_ITEM_KEY, 1G) because task A has not removed that key yet --> aborts the running transaction with error -EEXIST btrfs_del_item() -> removes the block group's key from the extent tree, key is (offset X, BTRFS_BLOCK_GROUP_ITEM_KEY, 1G) A sample transaction abort trace: [78912.403537] ------------[ cut here ]------------ [78912.403811] BTRFS: Transaction aborted (error -17) [78912.404082] WARNING: CPU: 2 PID: 20465 at fs/btrfs/extent-tree.c:10551 btrfs_create_pending_block_groups+0x196/0x250 [btrfs] (...) [78912.405642] CPU: 2 PID: 20465 Comm: btrfs Tainted: G W 5.0.0-btrfs-next-46 #1 [78912.405941] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014 [78912.406586] RIP: 0010:btrfs_create_pending_block_groups+0x196/0x250 [btrfs] (...) [78912.407636] RSP: 0018:ffff9d3d4b7e3b08 EFLAGS: 00010282 [78912.407997] RAX: 0000000000000000 RBX: ffff90959a3796f0 RCX: 0000000000000006 [78912.408369] RDX: 0000000000000007 RSI: 0000000000000001 RDI: ffff909636b16860 [78912.408746] RBP: ffff909626758a58 R08: 0000000000000000 R09: 0000000000000000 [78912.409144] R10: ffff9095ff462400 R11: 0000000000000000 R12: ffff90959a379588 [78912.409521] R13: ffff909626758ab0 R14: ffff9095036c0000 R15: ffff9095299e1158 [78912.409899] FS: 00007f387f16f700(0000) GS:ffff909636b00000(0000) knlGS:0000000000000000 [78912.410285] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [78912.410673] CR2: 00007f429fc87cbc CR3: 000000014440a004 CR4: 00000000003606e0 [78912.411095] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [78912.411496] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [78912.411898] Call Trace: [78912.412318] __btrfs_end_transaction+0x5b/0x1c0 [btrfs] [78912.412746] btrfs_inc_block_group_ro+0xcf/0x160 [btrfs] [78912.413179] scrub_enumerate_chunks+0x188/0x5b0 [btrfs] [78912.413622] ? __mutex_unlock_slowpath+0x100/0x2a0 [78912.414078] btrfs_scrub_dev+0x2ef/0x720 [btrfs] [78912.414535] ? __sb_start_write+0xd4/0x1c0 [78912.414963] ? mnt_want_write_file+0x24/0x50 [78912.415403] btrfs_ioctl+0x17fb/0x3120 [btrfs] [78912.415832] ? lock_acquire+0xa6/0x190 [78912.416256] ? do_vfs_ioctl+0xa2/0x6f0 [78912.416685] ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs] [78912.417116] do_vfs_ioctl+0xa2/0x6f0 [78912.417534] ? __fget+0x113/0x200 [78912.417954] ksys_ioctl+0x70/0x80 [78912.418369] __x64_sys_ioctl+0x16/0x20 [78912.418812] do_syscall_64+0x60/0x1b0 [78912.419231] entry_SYSCALL_64_after_hwframe+0x49/0xbe [78912.419644] RIP: 0033:0x7f3880252dd7 (...) [78912.420957] RSP: 002b:00007f387f16ed68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [78912.421426] RAX: ffffffffffffffda RBX: 000055f5becc1df0 RCX: 00007f3880252dd7 [78912.421889] RDX: 000055f5becc1df0 RSI: 00000000c400941b RDI: 0000000000000003 [78912.422354] RBP: 0000000000000000 R08: 00007f387f16f700 R09: 0000000000000000 [78912.422790] R10: 00007f387f16f700 R11: 0000000000000246 R12: 0000000000000000 [78912.423202] R13: 00007ffda49c266f R14: 0000000000000000 R15: 00007f388145e040 [78912.425505] ---[ end trace eb9bfe7c426fc4d3 ]--- Fix this by calling remove_extent_mapping(), at btrfs_remove_block_group(), only at the very end, after removing the block group item key from the extent tree (and removing the free space tree entry if we are using the free space tree feature). Fixes: 04216820fe83d5 ("Btrfs: fix race between fs trimming and block group remove/allocation") CC: stable@vger.kernel.org # 4.4+ Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2019-06-11Merge tag 'for-5.2-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fix from David Sterba: "One regression fix to TRIM ioctl. The range cannot be used as its meaning can be confusing regarding physical and logical addresses. This confusion in code led to potential corruptions when the range overlapped data. The original patch made it to several stable kernels and was promptly reverted, the version for master branch is different due to additional changes but the change is effectively the same" * tag 'for-5.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: Always trim all unallocated space in btrfs_trim_free_extents
2019-06-07btrfs: Always trim all unallocated space in btrfs_trim_free_extentsNikolay Borisov
This patch removes support for range parameters of FITRIM ioctl when trimming unallocated space on devices. This is necessary since ranges passed from user space are generally interpreted as logical addresses, whereas btrfs_trim_free_extents used to interpret them as device physical extents. This could result in counter-intuitive behavior for users so it's best to remove that support altogether. Additionally, the existing range support had a bug where if an offset was passed to FITRIM which overflows u64 e.g. -1 (parsed as u64 18446744073709551615) then wrong data was fed into btrfs_issue_discard, which in turn leads to wrap-around when aligning the passed range and results in wrong regions being discarded which leads to data corruption. Fixes: c2d1b3aae336 ("btrfs: Honour FITRIM range constraints during free space trim") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2019-05-30Merge tag 'for-5.2-rc2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A few more fixes for bugs reported by users, fuzzing tools and regressions: - fix crashes in relocation: + resuming interrupted balance operation does not properly clean up orphan trees + with enabled qgroups, resuming needs to be more careful about block groups due to limited context when updating qgroups - fsync and logging fixes found by fuzzing - incremental send fixes for no-holes and clone - fix spin lock type used in timer function for zstd" * tag 'for-5.2-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: Btrfs: fix race updating log root item during fsync Btrfs: fix wrong ctime and mtime of a directory after log replay Btrfs: fix fsync not persisting changed attributes of a directory btrfs: qgroup: Check bg while resuming relocation to avoid NULL pointer dereference btrfs: reloc: Also queue orphan reloc tree for cleanup to avoid BUG_ON() Btrfs: incremental send, fix emission of invalid clone operations Btrfs: incremental send, fix file corruption when no-holes feature is enabled btrfs: correct zstd workspace manager lock to use spin_lock_bh() btrfs: Ensure replaced device doesn't have pending chunk allocation