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2020-09-17net/compat: Add missing sock updates for SCM_RIGHTSKees Cook
commit d9539752d23283db4692384a634034f451261e29 upstream. Add missed sock updates to compat path via a new helper, which will be used more in coming patches. (The net/core/scm.c code is left as-is here to assist with -stable backports for the compat path.) Cc: Christoph Hellwig <hch@lst.de> Cc: Sargun Dhillon <sargun@sargun.me> Cc: Jakub Kicinski <kuba@kernel.org> Cc: stable@vger.kernel.org Fixes: 48a87cc26c13 ("net: netprio: fd passed in SCM_RIGHTS datagram not set correctly") Fixes: d84295067fc7 ("net: net_cls: fd passed in SCM_RIGHTS datagram not set correctly") Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-08-21net-sysfs: add a newline when printing 'tx_timeout' by sysfsXiongfeng Wang
commit 9bb5fbea59f36a589ef886292549ca4052fe676c upstream. When I cat 'tx_timeout' by sysfs, it displays as follows. It's better to add a newline for easy reading. root@syzkaller:~# cat /sys/devices/virtual/net/lo/queues/tx-0/tx_timeout 0root@syzkaller:~# Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-08-21dev: Defer free of skbs in flush_backlogSubash Abhinov Kasiviswanathan
commit 7df5cb75cfb8acf96c7f2342530eb41e0c11f4c3 upstream. IRQs are disabled when freeing skbs in input queue. Use the IRQ safe variant to free skbs here. Fixes: 145dd5f9c88f ("net: flush the softnet backlog in process context") Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-08-13cgroup: fix cgroup_sk_alloc() for sk_clone_lock()Cong Wang
commit ad0f75e5f57ccbceec13274e1e242f2b5a6397ed upstream. When we clone a socket in sk_clone_lock(), its sk_cgrp_data is copied, so the cgroup refcnt must be taken too. And, unlike the sk_alloc() path, sock_update_netprioidx() is not called here. Therefore, it is safe and necessary to grab the cgroup refcnt even when cgroup_sk_alloc is disabled. sk_clone_lock() is in BH context anyway, the in_interrupt() would terminate this function if called there. And for sk_alloc() skcd->val is always zero. So it's safe to factor out the code to make it more readable. The global variable 'cgroup_sk_alloc_disabled' is used to determine whether to take these reference counts. It is impossible to make the reference counting correct unless we save this bit of information in skcd->val. So, add a new bit there to record whether the socket has already taken the reference counts. This obviously relies on kmalloc() to align cgroup pointers to at least 4 bytes, ARCH_KMALLOC_MINALIGN is certainly larger than that. This bug seems to be introduced since the beginning, commit d979a39d7242 ("cgroup: duplicate cgroup reference when cloning sockets") tried to fix it but not compeletely. It seems not easy to trigger until the recent commit 090e28b229af ("netprio_cgroup: Fix unlimited memory leak of v2 cgroups") was merged. Fixes: bd1060a1d671 ("sock, cgroup: add sock->sk_cgroup") Reported-by: Cameron Berkenpas <cam@neo-zeon.de> Reported-by: Peter Geis <pgwipeout@gmail.com> Reported-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com> Reported-by: Daniël Sonck <dsonck92@gmail.com> Reported-by: Zhang Qiang <qiang.zhang@windriver.com> Tested-by: Cameron Berkenpas <cam@neo-zeon.de> Tested-by: Peter Geis <pgwipeout@gmail.com> Tested-by: Thomas Lamprecht <t.lamprecht@proxmox.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Zefan Li <lizefan@huawei.com> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <guro@fb.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [PG: use 4.19.134-stable version instead of mainline.] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-08-13sched: consistently handle layer3 header accesses in the presence of VLANsToke Høiland-Jørgensen
commit d7bf2ebebc2bd61ab95e2a8e33541ef282f303d4 upstream. There are a couple of places in net/sched/ that check skb->protocol and act on the value there. However, in the presence of VLAN tags, the value stored in skb->protocol can be inconsistent based on whether VLAN acceleration is enabled. The commit quoted in the Fixes tag below fixed the users of skb->protocol to use a helper that will always see the VLAN ethertype. However, most of the callers don't actually handle the VLAN ethertype, but expect to find the IP header type in the protocol field. This means that things like changing the ECN field, or parsing diffserv values, stops working if there's a VLAN tag, or if there are multiple nested VLAN tags (QinQ). To fix this, change the helper to take an argument that indicates whether the caller wants to skip the VLAN tags or not. When skipping VLAN tags, we make sure to skip all of them, so behaviour is consistent even in QinQ mode. To make the helper usable from the ECN code, move it to if_vlan.h instead of pkt_sched.h. v3: - Remove empty lines - Move vlan variable definitions inside loop in skb_protocol() - Also use skb_protocol() helper in IP{,6}_ECN_decapsulate() and bpf_skb_ecn_set_ce() v2: - Use eth_type_vlan() helper in skb_protocol() - Also fix code that reads skb->protocol directly - Change a couple of 'if/else if' statements to switch constructs to avoid calling the helper twice Reported-by: Ilya Ponetayev <i.ponetaev@ndmsystems.com> Fixes: d8b9605d2697 ("net: sched: fix skb->protocol use in case of accelerated vlan path") Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> [PG: start with 4.19.134-stable version - we don't have v5.3-rc1~140^2~15^2~3] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-08-03udp: Copy has_conns in reuseport_grow().Kuniyuki Iwashima
commit f2b2c55e512879a05456eaf5de4d1ed2f7757509 upstream. If an unconnected socket in a UDP reuseport group connect()s, has_conns is set to 1. Then, when a packet is received, udp[46]_lib_lookup2() scans all sockets in udp_hslot looking for the connected socket with the highest score. However, when the number of sockets bound to the port exceeds max_socks, reuseport_grow() resets has_conns to 0. It can cause udp[46]_lib_lookup2() to return without scanning all sockets, resulting in that packets sent to connected sockets may be distributed to unconnected sockets. Therefore, reuseport_grow() should copy has_conns. Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets") CC: Willem de Bruijn <willemb@google.com> Reviewed-by: Benjamin Herrenschmidt <benh@amazon.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-08-03rtnetlink: Fix memory(net_device) leak when ->newlink failsWeilong Chen
commit cebb69754f37d68e1355a5e726fdac317bcda302 upstream. When vlan_newlink call register_vlan_dev fails, it might return error with dev->reg_state = NETREG_UNREGISTERED. The rtnl_newlink should free the memory. But currently rtnl_newlink only free the memory which state is NETREG_UNINITIALIZED. BUG: memory leak unreferenced object 0xffff8881051de000 (size 4096): comm "syz-executor139", pid 560, jiffies 4294745346 (age 32.445s) hex dump (first 32 bytes): 76 6c 61 6e 32 00 00 00 00 00 00 00 00 00 00 00 vlan2........... 00 45 28 03 81 88 ff ff 00 00 00 00 00 00 00 00 .E(............. backtrace: [<0000000047527e31>] kmalloc_node include/linux/slab.h:578 [inline] [<0000000047527e31>] kvmalloc_node+0x33/0xd0 mm/util.c:574 [<000000002b59e3bc>] kvmalloc include/linux/mm.h:753 [inline] [<000000002b59e3bc>] kvzalloc include/linux/mm.h:761 [inline] [<000000002b59e3bc>] alloc_netdev_mqs+0x83/0xd90 net/core/dev.c:9929 [<000000006076752a>] rtnl_create_link+0x2c0/0xa20 net/core/rtnetlink.c:3067 [<00000000572b3be5>] __rtnl_newlink+0xc9c/0x1330 net/core/rtnetlink.c:3329 [<00000000e84ea553>] rtnl_newlink+0x66/0x90 net/core/rtnetlink.c:3397 [<0000000052c7c0a9>] rtnetlink_rcv_msg+0x540/0x990 net/core/rtnetlink.c:5460 [<000000004b5cb379>] netlink_rcv_skb+0x12b/0x3a0 net/netlink/af_netlink.c:2469 [<00000000c71c20d3>] netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] [<00000000c71c20d3>] netlink_unicast+0x4c6/0x690 net/netlink/af_netlink.c:1329 [<00000000cca72fa9>] netlink_sendmsg+0x735/0xcc0 net/netlink/af_netlink.c:1918 [<000000009221ebf7>] sock_sendmsg_nosec net/socket.c:652 [inline] [<000000009221ebf7>] sock_sendmsg+0x109/0x140 net/socket.c:672 [<000000001c30ffe4>] ____sys_sendmsg+0x5f5/0x780 net/socket.c:2352 [<00000000b71ca6f3>] ___sys_sendmsg+0x11d/0x1a0 net/socket.c:2406 [<0000000007297384>] __sys_sendmsg+0xeb/0x1b0 net/socket.c:2439 [<000000000eb29b11>] do_syscall_64+0x56/0xa0 arch/x86/entry/common.c:359 [<000000006839b4d0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: cb626bf566eb ("net-sysfs: Fix reference count leak") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-16net: increment xmit_recursion level in dev_direct_xmit()Eric Dumazet
commit 0ad6f6e767ec2f613418cbc7ebe5ec4c35af540c upstream. Back in commit f60e5990d9c1 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack") Hannes added code so that IPv6 stack would not trust skb->sk for typical cases where packet goes through 'standard' xmit path (__dev_queue_xmit()) Alas af_packet had a dev_direct_xmit() path that was not dealing yet with xmit_recursion level. Also change sk_mc_loop() to dump a stack once only. Without this patch, syzbot was able to trigger : [1] [ 153.567378] WARNING: CPU: 7 PID: 11273 at net/core/sock.c:721 sk_mc_loop+0x51/0x70 [ 153.567378] Modules linked in: nfnetlink ip6table_raw ip6table_filter iptable_raw iptable_nat nf_nat nf_conntrack nf_defrag_ipv4 nf_defrag_ipv6 iptable_filter macsec macvtap tap macvlan 8021q hsr wireguard libblake2s blake2s_x86_64 libblake2s_generic udp_tunnel ip6_udp_tunnel libchacha20poly1305 poly1305_x86_64 chacha_x86_64 libchacha curve25519_x86_64 libcurve25519_generic netdevsim batman_adv dummy team bridge stp llc w1_therm wire i2c_mux_pca954x i2c_mux cdc_acm ehci_pci ehci_hcd mlx4_en mlx4_ib ib_uverbs ib_core mlx4_core [ 153.567386] CPU: 7 PID: 11273 Comm: b159172088 Not tainted 5.8.0-smp-DEV #273 [ 153.567387] RIP: 0010:sk_mc_loop+0x51/0x70 [ 153.567388] Code: 66 83 f8 0a 75 24 0f b6 4f 12 b8 01 00 00 00 31 d2 d3 e0 a9 bf ef ff ff 74 07 48 8b 97 f0 02 00 00 0f b6 42 3a 83 e0 01 5d c3 <0f> 0b b8 01 00 00 00 5d c3 0f b6 87 18 03 00 00 5d c0 e8 04 83 e0 [ 153.567388] RSP: 0018:ffff95c69bb93990 EFLAGS: 00010212 [ 153.567388] RAX: 0000000000000011 RBX: ffff95c6e0ee3e00 RCX: 0000000000000007 [ 153.567389] RDX: ffff95c69ae50000 RSI: ffff95c6c30c3000 RDI: ffff95c6c30c3000 [ 153.567389] RBP: ffff95c69bb93990 R08: ffff95c69a77f000 R09: 0000000000000008 [ 153.567389] R10: 0000000000000040 R11: 00003e0e00026128 R12: ffff95c6c30c3000 [ 153.567390] R13: ffff95c6cc4fd500 R14: ffff95c6f84500c0 R15: ffff95c69aa13c00 [ 153.567390] FS: 00007fdc3a283700(0000) GS:ffff95c6ff9c0000(0000) knlGS:0000000000000000 [ 153.567390] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 153.567391] CR2: 00007ffee758e890 CR3: 0000001f9ba20003 CR4: 00000000001606e0 [ 153.567391] Call Trace: [ 153.567391] ip6_finish_output2+0x34e/0x550 [ 153.567391] __ip6_finish_output+0xe7/0x110 [ 153.567391] ip6_finish_output+0x2d/0xb0 [ 153.567392] ip6_output+0x77/0x120 [ 153.567392] ? __ip6_finish_output+0x110/0x110 [ 153.567392] ip6_local_out+0x3d/0x50 [ 153.567392] ipvlan_queue_xmit+0x56c/0x5e0 [ 153.567393] ? ksize+0x19/0x30 [ 153.567393] ipvlan_start_xmit+0x18/0x50 [ 153.567393] dev_direct_xmit+0xf3/0x1c0 [ 153.567393] packet_direct_xmit+0x69/0xa0 [ 153.567394] packet_sendmsg+0xbf0/0x19b0 [ 153.567394] ? plist_del+0x62/0xb0 [ 153.567394] sock_sendmsg+0x65/0x70 [ 153.567394] sock_write_iter+0x93/0xf0 [ 153.567394] new_sync_write+0x18e/0x1a0 [ 153.567395] __vfs_write+0x29/0x40 [ 153.567395] vfs_write+0xb9/0x1b0 [ 153.567395] ksys_write+0xb1/0xe0 [ 153.567395] __x64_sys_write+0x1a/0x20 [ 153.567395] do_syscall_64+0x43/0x70 [ 153.567396] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 153.567396] RIP: 0033:0x453549 [ 153.567396] Code: Bad RIP value. [ 153.567396] RSP: 002b:00007fdc3a282cc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 153.567397] RAX: ffffffffffffffda RBX: 00000000004d32d0 RCX: 0000000000453549 [ 153.567397] RDX: 0000000000000020 RSI: 0000000020000300 RDI: 0000000000000003 [ 153.567398] RBP: 00000000004d32d8 R08: 0000000000000000 R09: 0000000000000000 [ 153.567398] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004d32dc [ 153.567398] R13: 00007ffee742260f R14: 00007fdc3a282dc0 R15: 00007fdc3a283700 [ 153.567399] ---[ end trace c1d5ae2b1059ec62 ]--- f60e5990d9c1 ("ipv6: protect skb->sk accesses from recursive dereference inside the stack") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-16net: fix memleak in register_netdevice()Yang Yingliang
commit 814152a89ed52c722ab92e9fbabcac3cb8a39245 upstream. I got a memleak report when doing some fuzz test: unreferenced object 0xffff888112584000 (size 13599): comm "ip", pid 3048, jiffies 4294911734 (age 343.491s) hex dump (first 32 bytes): 74 61 70 30 00 00 00 00 00 00 00 00 00 00 00 00 tap0............ 00 ee d9 19 81 88 ff ff 00 00 00 00 00 00 00 00 ................ backtrace: [<000000002f60ba65>] __kmalloc_node+0x309/0x3a0 [<0000000075b211ec>] kvmalloc_node+0x7f/0xc0 [<00000000d3a97396>] alloc_netdev_mqs+0x76/0xfc0 [<00000000609c3655>] __tun_chr_ioctl+0x1456/0x3d70 [<000000001127ca24>] ksys_ioctl+0xe5/0x130 [<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0 [<00000000e1023498>] do_syscall_64+0x56/0xa0 [<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 unreferenced object 0xffff888111845cc0 (size 8): comm "ip", pid 3048, jiffies 4294911734 (age 343.491s) hex dump (first 8 bytes): 74 61 70 30 00 88 ff ff tap0.... backtrace: [<000000004c159777>] kstrdup+0x35/0x70 [<00000000d8b496ad>] kstrdup_const+0x3d/0x50 [<00000000494e884a>] kvasprintf_const+0xf1/0x180 [<0000000097880a2b>] kobject_set_name_vargs+0x56/0x140 [<000000008fbdfc7b>] dev_set_name+0xab/0xe0 [<000000005b99e3b4>] netdev_register_kobject+0xc0/0x390 [<00000000602704fe>] register_netdevice+0xb61/0x1250 [<000000002b7ca244>] __tun_chr_ioctl+0x1cd1/0x3d70 [<000000001127ca24>] ksys_ioctl+0xe5/0x130 [<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0 [<00000000e1023498>] do_syscall_64+0x56/0xa0 [<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 unreferenced object 0xffff88811886d800 (size 512): comm "ip", pid 3048, jiffies 4294911734 (age 343.491s) hex dump (first 32 bytes): 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... ff ff ff ff ff ff ff ff c0 66 3d a3 ff ff ff ff .........f=..... backtrace: [<0000000050315800>] device_add+0x61e/0x1950 [<0000000021008dfb>] netdev_register_kobject+0x17e/0x390 [<00000000602704fe>] register_netdevice+0xb61/0x1250 [<000000002b7ca244>] __tun_chr_ioctl+0x1cd1/0x3d70 [<000000001127ca24>] ksys_ioctl+0xe5/0x130 [<00000000b7d5e66a>] __x64_sys_ioctl+0x6f/0xb0 [<00000000e1023498>] do_syscall_64+0x56/0xa0 [<000000009ec0eb12>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 If call_netdevice_notifiers() failed, then rollback_registered() calls netdev_unregister_kobject() which holds the kobject. The reference cannot be put because the netdev won't be add to todo list, so it will leads a memleak, we need put the reference to avoid memleak. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-16net: Do not clear the sock TX queue in sk_set_socket()Tariq Toukan
commit 41b14fb8724d5a4b382a63cb4a1a61880347ccb8 upstream. Clearing the sock TX queue in sk_set_socket() might cause unexpected out-of-order transmit when called from sock_orphan(), as outstanding packets can pick a different TX queue and bypass the ones already queued. This is undesired in general. More specifically, it breaks the in-order scheduling property guarantee for device-offloaded TLS sockets. Remove the call to sk_tx_queue_clear() in sk_set_socket(), and add it explicitly only where needed. Fixes: e022f0b4a03f ("net: Introduce sk_tx_queue_mapping") Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Reviewed-by: Boris Pismenny <borisp@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-13net: core: device_rename: Use rwsem instead of a seqcountAhmed S. Darwish
commit 11d6011c2cf29f7c8181ebde6c8bc0c4d83adcd7 upstream. Sequence counters write paths are critical sections that must never be preempted, and blocking, even for CONFIG_PREEMPTION=n, is not allowed. Commit 5dbe7c178d3f ("net: fix kernel deadlock with interface rename and netdev name retrieval.") handled a deadlock, observed with CONFIG_PREEMPTION=n, where the devnet_rename seqcount read side was infinitely spinning: it got scheduled after the seqcount write side blocked inside its own critical section. To fix that deadlock, among other issues, the commit added a cond_resched() inside the read side section. While this will get the non-preemptible kernel eventually unstuck, the seqcount reader is fully exhausting its slice just spinning -- until TIF_NEED_RESCHED is set. The fix is also still broken: if the seqcount reader belongs to a real-time scheduling policy, it can spin forever and the kernel will livelock. Disabling preemption over the seqcount write side critical section will not work: inside it are a number of GFP_KERNEL allocations and mutex locking through the drivers/base/ :: device_rename() call chain. >From all the above, replace the seqcount with a rwsem. Fixes: 5dbe7c178d3f (net: fix kernel deadlock with interface rename and netdev name retrieval.) Fixes: 30e6c9fa93cf (net: devnet_rename_seq should be a seqcount) Fixes: c91f6df2db49 (sockopt: Change getsockopt() of SO_BINDTODEVICE to return an interface name) Cc: <stable@vger.kernel.org> Reported-by: kbuild test robot <lkp@intel.com> [ v1 missing up_read() on error exit ] Reported-by: Dan Carpenter <dan.carpenter@oracle.com> [ v1 missing up_read() on error exit ] Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-13sched/rt, net: Use CONFIG_PREEMPTION.patchThomas Gleixner
commit 2da2b32fd9346009e9acdb68c570ca8d3966aba7 upstream. CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Update the comment to use CONFIG_PREEMPTION. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David S. Miller <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: netdev@vger.kernel.org Link: https://lore.kernel.org/r/20191015191821.11479-22-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-13net/filter: Permit reading NET in load_bytes_relative when MAC not setYiFei Zhu
commit 0f5d82f187e1beda3fe7295dfc500af266a5bd80 upstream. Added a check in the switch case on start_header that checks for the existence of the header, and in the case that MAC is not set and the caller requests for MAC, -EFAULT. If the caller requests for NET then MAC's existence is completely ignored. There is no function to check NET header's existence and as far as cgroup_skb/egress is concerned it should always be set. Removed for ptr >= the start of header, considering offset is bounded unsigned and should always be true. len <= end - mac is redundant to ptr + len <= end. Fixes: 3eee1f75f2b9 ("bpf: fix bpf_skb_load_bytes_relative pkt length check") Signed-off-by: YiFei Zhu <zhuyifei@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/76bb820ddb6a95f59a772ecbd8c8a336f646b362.1591812755.git.zhuyifei@google.com Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-13bpf, sockhash: Fix memory leak when unlinking sockets in sock_hash_freeJakub Sitnicki
commit 33a7c831565c43a7ee2f38c7df4c4a40e1dfdfed upstream. When sockhash gets destroyed while sockets are still linked to it, we will walk the bucket lists and delete the links. However, we are not freeing the list elements after processing them, leaking the memory. The leak can be triggered by close()'ing a sockhash map when it still contains sockets, and observed with kmemleak: unreferenced object 0xffff888116e86f00 (size 64): comm "race_sock_unlin", pid 223, jiffies 4294731063 (age 217.404s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 81 de e8 41 00 00 00 00 c0 69 2f 15 81 88 ff ff ...A.....i/..... backtrace: [<00000000dd089ebb>] sock_hash_update_common+0x4ca/0x760 [<00000000b8219bd5>] sock_hash_update_elem+0x1d2/0x200 [<000000005e2c23de>] __do_sys_bpf+0x2046/0x2990 [<00000000d0084618>] do_syscall_64+0xad/0x9a0 [<000000000d96f263>] entry_SYSCALL_64_after_hwframe+0x49/0xb3 Fix it by freeing the list element when we're done with it. Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200607205229.2389672-2-jakub@cloudflare.com Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-11bpf, sockmap: RCU dereferenced psock may be used outside RCU blockJohn Fastabend
commit 8025751d4d55a2f32be6bdf825b6a80c299875f5 upstream. If an ingress verdict program specifies message sizes greater than skb->len and there is an ENOMEM error due to memory pressure we may call the rcv_msg handler outside the strp_data_ready() caller context. This is because on an ENOMEM error the strparser will retry from a workqueue. The caller currently protects the use of psock by calling the strp_data_ready() inside a rcu_read_lock/unlock block. But, in above workqueue error case the psock is accessed outside the read_lock/unlock block of the caller. So instead of using psock directly we must do a look up against the sk again to ensure the psock is available. There is an an ugly piece here where we must handle the case where we paused the strp and removed the psock. On psock removal we first pause the strparser and then remove the psock. If the strparser is paused while an skb is scheduled on the workqueue the skb will be dropped on the flow and kfree_skb() is called. If the workqueue manages to get called before we pause the strparser but runs the rcvmsg callback after the psock is removed we will hit the unlikely case where we run the sockmap rcvmsg handler but do not have a psock. For now we will follow strparser logic and drop the skb on the floor with skb_kfree(). This is ugly because the data is dropped. To date this has not caused problems in practice because either the application controlling the sockmap is coordinating with the datapath so that skbs are "flushed" before removal or we simply wait for the sock to be closed before removing it. This patch fixes the describe RCU bug and dropping the skb doesn't make things worse. Future patches will improve this by allowing the normal case where skbs are not merged to skip the strparser altogether. In practice many (most?) use cases have no need to merge skbs so its both a code complexity hit as seen above and a performance issue. For example, in the Cilium case we always set the strparser up to return sbks 1:1 without any merging and have avoided above issues. Fixes: e91de6afa81c1 ("bpf: Fix running sk_skb program types with ktls") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/159312679888.18340.15248924071966273998.stgit@john-XPS-13-9370 Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-11bpf, sockmap: RCU splat with redirect and strparser error or TLSJohn Fastabend
commit 93dd5f185916b05e931cffae636596f21f98546e upstream. There are two paths to generate the below RCU splat the first and most obvious is the result of the BPF verdict program issuing a redirect on a TLS socket (This is the splat shown below). Unlike the non-TLS case the caller of the *strp_read() hooks does not wrap the call in a rcu_read_lock/unlock. Then if the BPF program issues a redirect action we hit the RCU splat. However, in the non-TLS socket case the splat appears to be relatively rare, because the skmsg caller into the strp_data_ready() is wrapped in a rcu_read_lock/unlock. Shown here, static void sk_psock_strp_data_ready(struct sock *sk) { struct sk_psock *psock; rcu_read_lock(); psock = sk_psock(sk); if (likely(psock)) { if (tls_sw_has_ctx_rx(sk)) { psock->parser.saved_data_ready(sk); } else { write_lock_bh(&sk->sk_callback_lock); strp_data_ready(&psock->parser.strp); write_unlock_bh(&sk->sk_callback_lock); } } rcu_read_unlock(); } If the above was the only way to run the verdict program we would be safe. But, there is a case where the strparser may throw an ENOMEM error while parsing the skb. This is a result of a failed skb_clone, or alloc_skb_for_msg while building a new merged skb when the msg length needed spans multiple skbs. This will in turn put the skb on the strp_wrk workqueue in the strparser code. The skb will later be dequeued and verdict programs run, but now from a different context without the rcu_read_lock()/unlock() critical section in sk_psock_strp_data_ready() shown above. In practice I have not seen this yet, because as far as I know most users of the verdict programs are also only working on single skbs. In this case no merge happens which could trigger the above ENOMEM errors. In addition the system would need to be under memory pressure. For example, we can't hit the above case in selftests because we missed having tests to merge skbs. (Added in later patch) To fix the below splat extend the rcu_read_lock/unnlock block to include the call to sk_psock_tls_verdict_apply(). This will fix both TLS redirect case and non-TLS redirect+error case. Also remove psock from the sk_psock_tls_verdict_apply() function signature its not used there. [ 1095.937597] WARNING: suspicious RCU usage [ 1095.940964] 5.7.0-rc7-02911-g463bac5f1ca79 #1 Tainted: G W [ 1095.944363] ----------------------------- [ 1095.947384] include/linux/skmsg.h:284 suspicious rcu_dereference_check() usage! [ 1095.950866] [ 1095.950866] other info that might help us debug this: [ 1095.950866] [ 1095.957146] [ 1095.957146] rcu_scheduler_active = 2, debug_locks = 1 [ 1095.961482] 1 lock held by test_sockmap/15970: [ 1095.964501] #0: ffff9ea6b25de660 (sk_lock-AF_INET){+.+.}-{0:0}, at: tls_sw_recvmsg+0x13a/0x840 [tls] [ 1095.968568] [ 1095.968568] stack backtrace: [ 1095.975001] CPU: 1 PID: 15970 Comm: test_sockmap Tainted: G W 5.7.0-rc7-02911-g463bac5f1ca79 #1 [ 1095.977883] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 1095.980519] Call Trace: [ 1095.982191] dump_stack+0x8f/0xd0 [ 1095.984040] sk_psock_skb_redirect+0xa6/0xf0 [ 1095.986073] sk_psock_tls_strp_read+0x1d8/0x250 [ 1095.988095] tls_sw_recvmsg+0x714/0x840 [tls] v2: Improve commit message to identify non-TLS redirect plus error case condition as well as more common TLS case. In the process I decided doing the rcu_read_unlock followed by the lock/unlock inside branches was unnecessarily complex. We can just extend the current rcu block and get the same effeective without the shuffling and branching. Thanks Martin! Fixes: e91de6afa81c1 ("bpf: Fix running sk_skb program types with ktls") Reported-by: Jakub Sitnicki <jakub@cloudflare.com> Reported-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/159312677907.18340.11064813152758406626.stgit@john-XPS-13-9370 Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-11bpf: Fix running sk_skb program types with ktlsJohn Fastabend
commit e91de6afa81c10e9f855c5695eb9a53168d96b73 upstream. KTLS uses a stream parser to collect TLS messages and send them to the upper layer tls receive handler. This ensures the tls receiver has a full TLS header to parse when it is run. However, when a socket has BPF_SK_SKB_STREAM_VERDICT program attached before KTLS is enabled we end up with two stream parsers running on the same socket. The result is both try to run on the same socket. First the KTLS stream parser runs and calls read_sock() which will tcp_read_sock which in turn calls tcp_rcv_skb(). This dequeues the skb from the sk_receive_queue. When this is done KTLS code then data_ready() callback which because we stacked KTLS on top of the bpf stream verdict program has been replaced with sk_psock_start_strp(). This will in turn kick the stream parser again and eventually do the same thing KTLS did above calling into tcp_rcv_skb() and dequeuing a skb from the sk_receive_queue. At this point the data stream is broke. Part of the stream was handled by the KTLS side some other bytes may have been handled by the BPF side. Generally this results in either missing data or more likely a "Bad Message" complaint from the kTLS receive handler as the BPF program steals some bytes meant to be in a TLS header and/or the TLS header length is no longer correct. We've already broke the idealized model where we can stack ULPs in any order with generic callbacks on the TX side to handle this. So in this patch we do the same thing but for RX side. We add a sk_psock_strp_enabled() helper so TLS can learn a BPF verdict program is running and add a tls_sw_has_ctx_rx() helper so BPF side can learn there is a TLS ULP on the socket. Then on BPF side we omit calling our stream parser to avoid breaking the data stream for the KTLS receiver. Then on the KTLS side we call BPF_SK_SKB_STREAM_VERDICT once the KTLS receiver is done with the packet but before it posts the msg to userspace. This gives us symmetry between the TX and RX halfs and IMO makes it usable again. On the TX side we process packets in this order BPF -> TLS -> TCP and on the receive side in the reverse order TCP -> TLS -> BPF. Discovered while testing OpenSSL 3.0 Alpha2.0 release. Fixes: d829e9c4112b5 ("tls: convert to generic sk_msg interface") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/159079361946.5745.605854335665044485.stgit@john-Precision-5820-Tower Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-07-11bpf: Refactor sockmap redirect code so its easy to reuseJohn Fastabend
commit ca2f5f21dbbd5e3a00cd3e97f728aa2ca0b2e011 upstream. We will need this block of code called from tls context shortly lets refactor the redirect logic so its easy to use. This also cleans up the switch stmt so we have fewer fallthrough cases. No logic changes are intended. Fixes: d829e9c4112b5 ("tls: convert to generic sk_msg interface") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/159079360110.5745.7024009076049029819.stgit@john-Precision-5820-Tower Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-24bpf, sockhash: Synchronize delete from bucket list on map freeJakub Sitnicki
commit 75e68e5bf2c7fa9d3e874099139df03d5952a3e1 upstream. We can end up modifying the sockhash bucket list from two CPUs when a sockhash is being destroyed (sock_hash_free) on one CPU, while a socket that is in the sockhash is unlinking itself from it on another CPU it (sock_hash_delete_from_link). This results in accessing a list element that is in an undefined state as reported by KASAN: | ================================================================== | BUG: KASAN: wild-memory-access in sock_hash_free+0x13c/0x280 | Write of size 8 at addr dead000000000122 by task kworker/2:1/95 | | CPU: 2 PID: 95 Comm: kworker/2:1 Not tainted 5.7.0-rc7-02961-ge22c35ab0038-dirty #691 | Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014 | Workqueue: events bpf_map_free_deferred | Call Trace: | dump_stack+0x97/0xe0 | ? sock_hash_free+0x13c/0x280 | __kasan_report.cold+0x5/0x40 | ? mark_lock+0xbc1/0xc00 | ? sock_hash_free+0x13c/0x280 | kasan_report+0x38/0x50 | ? sock_hash_free+0x152/0x280 | sock_hash_free+0x13c/0x280 | bpf_map_free_deferred+0xb2/0xd0 | ? bpf_map_charge_finish+0x50/0x50 | ? rcu_read_lock_sched_held+0x81/0xb0 | ? rcu_read_lock_bh_held+0x90/0x90 | process_one_work+0x59a/0xac0 | ? lock_release+0x3b0/0x3b0 | ? pwq_dec_nr_in_flight+0x110/0x110 | ? rwlock_bug.part.0+0x60/0x60 | worker_thread+0x7a/0x680 | ? _raw_spin_unlock_irqrestore+0x4c/0x60 | kthread+0x1cc/0x220 | ? process_one_work+0xac0/0xac0 | ? kthread_create_on_node+0xa0/0xa0 | ret_from_fork+0x24/0x30 | ================================================================== Fix it by reintroducing spin-lock protected critical section around the code that removes the elements from the bucket on sockhash free. To do that we also need to defer processing of removed elements, until out of atomic context so that we can unlink the socket from the map when holding the sock lock. Fixes: 90db6d772f74 ("bpf, sockmap: Remove bucket->lock from sock_{hash|map}_free") Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200607205229.2389672-3-jakub@cloudflare.com Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-08netns: restore ops before calling ops_exit_listLi RongQing
commit b272a0ad730103e84fb735fd0a8cc050cdf7f77c upstream. ops has been iterated to first element when call pre_exit, and it needs to restore from save_ops, not save ops to save_ops Fixes: d7d99872c144 ("netns: add pre_exit method to struct pernet_operations") Signed-off-by: Li RongQing <lirongqing@baidu.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-08__netif_receive_skb_core: pass skb by referenceBoris Sukholitko
commit c0bbbdc32febd4f034ecbf3ea17865785b2c0652 upstream. __netif_receive_skb_core may change the skb pointer passed into it (e.g. in rx_handler). The original skb may be freed as a result of this operation. The callers of __netif_receive_skb_core may further process original skb by using pt_prev pointer returned by __netif_receive_skb_core thus leading to unpleasant effects. The solution is to pass skb by reference into __netif_receive_skb_core. v2: Added Fixes tag and comment regarding ppt_prev and skb invariant. Fixes: 88eb1944e18c ("net: core: propagate SKB lists through packet_type lookup") Signed-off-by: Boris Sukholitko <boris.sukholitko@broadcom.com> Acked-by: Edward Cree <ecree@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-08flow_dissector: Drop BPF flow dissector prog ref on netns cleanupJakub Sitnicki
commit 5cf65922bb15279402e1e19b5ee8c51d618fa51f upstream. When attaching a flow dissector program to a network namespace with bpf(BPF_PROG_ATTACH, ...) we grab a reference to bpf_prog. If netns gets destroyed while a flow dissector is still attached, and there are no other references to the prog, we leak the reference and the program remains loaded. Leak can be reproduced by running flow dissector tests from selftests/bpf: # bpftool prog list # ./test_flow_dissector.sh ... selftests: test_flow_dissector [PASS] # bpftool prog list 4: flow_dissector name _dissect tag e314084d332a5338 gpl loaded_at 2020-05-20T18:50:53+0200 uid 0 xlated 552B jited 355B memlock 4096B map_ids 3,4 btf_id 4 # Fix it by detaching the flow dissector program when netns is going away. Fixes: d58e468b1112 ("flow_dissector: implements flow dissector BPF hook") Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20200521083435.560256-1-jakub@cloudflare.com Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-08netns: add pre_exit method to struct pernet_operationsEric Dumazet
commit d7d99872c144a2c2f5d9c9d83627fa833836cba5 upstream. Current struct pernet_operations exit() handlers are highly discouraged to call synchronize_rcu(). There are cases where we need them, and exit_batch() does not help the common case where a single netns is dismantled. This patch leverages the existing synchronize_rcu() call in cleanup_net() Calling optional ->pre_exit() method before ->exit() or ->exit_batch() allows to benefit from a single synchronize_rcu() call. Note that the synchronize_rcu() calls added in this patch are only in error paths or slow paths. Tested: $ time for i in {1..1000}; do unshare -n /bin/false;done real 0m2.612s user 0m0.171s sys 0m2.216s Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-08bpf, sockmap: msg_pop_data can incorrecty set an sge lengthJohn Fastabend
commit 3e104c23816220919ea1b3fd93fabe363c67c484 upstream. When sk_msg_pop() is called where the pop operation is working on the end of a sge element and there is no additional trailing data and there _is_ data in front of pop, like the following case, |____________a_____________|__pop__| We have out of order operations where we incorrectly set the pop variable so that instead of zero'ing pop we incorrectly leave it untouched, effectively. This can cause later logic to shift the buffers around believing it should pop extra space. The result is we have 'popped' more data then we expected potentially breaking program logic. It took us a while to hit this case because typically we pop headers which seem to rarely be at the end of a scatterlist elements but we can't rely on this. Fixes: 7246d8ed4dcce ("bpf: helper to pop data from messages") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/158861288359.14306.7654891716919968144.stgit@john-Precision-5820-Tower Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-08netprio_cgroup: Fix unlimited memory leak of v2 cgroupsZefan Li
commit 090e28b229af92dc5b40786ca673999d59e73056 upstream. If systemd is configured to use hybrid mode which enables the use of both cgroup v1 and v2, systemd will create new cgroup on both the default root (v2) and netprio_cgroup hierarchy (v1) for a new session and attach task to the two cgroups. If the task does some network thing then the v2 cgroup can never be freed after the session exited. One of our machines ran into OOM due to this memory leak. In the scenario described above when sk_alloc() is called cgroup_sk_alloc() thought it's in v2 mode, so it stores the cgroup pointer in sk->sk_cgrp_data and increments the cgroup refcnt, but then sock_update_netprioidx() thought it's in v1 mode, so it stores netprioidx value in sk->sk_cgrp_data, so the cgroup refcnt will never be freed. Currently we do the mode switch when someone writes to the ifpriomap cgroup control file. The easiest fix is to also do the switch when a task is attached to a new cgroup. Fixes: bd1060a1d671 ("sock, cgroup: add sock->sk_cgroup") Reported-by: Yang Yingliang <yangyingliang@huawei.com> Tested-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Zefan Li <lizefan@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-08net: fix a potential recursive NETDEV_FEAT_CHANGECong Wang
commit dd912306ff008891c82cd9f63e8181e47a9cb2fb upstream. syzbot managed to trigger a recursive NETDEV_FEAT_CHANGE event between bonding master and slave. I managed to find a reproducer for this: ip li set bond0 up ifenslave bond0 eth0 brctl addbr br0 ethtool -K eth0 lro off brctl addif br0 bond0 ip li set br0 up When a NETDEV_FEAT_CHANGE event is triggered on a bonding slave, it captures this and calls bond_compute_features() to fixup its master's and other slaves' features. However, when syncing with its lower devices by netdev_sync_lower_features() this event is triggered again on slaves when the LRO feature fails to change, so it goes back and forth recursively until the kernel stack is exhausted. Commit 17b85d29e82c intentionally lets __netdev_update_features() return -1 for such a failure case, so we have to just rely on the existing check inside netdev_sync_lower_features() and skip NETDEV_FEAT_CHANGE event only for this specific failure case. Fixes: fd867d51f889 ("net/core: generic support for disabling netdev features down stack") Reported-by: syzbot+e73ceacfd8560cc8a3ca@syzkaller.appspotmail.com Reported-by: syzbot+c2fb6f9ddcea95ba49b5@syzkaller.appspotmail.com Cc: Jarod Wilson <jarod@redhat.com> Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jann Horn <jannh@google.com> Reviewed-by: Jay Vosburgh <jay.vosburgh@canonical.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-08drop_monitor: work around gcc-10 stringop-overflow warningArnd Bergmann
commit dc30b4059f6e2abf3712ab537c8718562b21c45d upstream. The current gcc-10 snapshot produces a false-positive warning: net/core/drop_monitor.c: In function 'trace_drop_common.constprop': cc1: error: writing 8 bytes into a region of size 0 [-Werror=stringop-overflow=] In file included from net/core/drop_monitor.c:23: include/uapi/linux/net_dropmon.h:36:8: note: at offset 0 to object 'entries' with size 4 declared here 36 | __u32 entries; | ^~~~~~~ I reported this in the gcc bugzilla, but in case it does not get fixed in the release, work around it by using a temporary variable. Fixes: 9a8afc8d3962 ("Network Drop Monitor: Adding drop monitor implementation & Netlink protocol") Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94881 Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-04neigh: send protocol value in neighbor create notificationRoman Mashak
commit 38212bb31fe923d0a2c6299bd2adfbb84cddef2a upstream. When a new neighbor entry has been added, event is generated but it does not include protocol, because its value is assigned after the event notification routine has run, so move protocol assignment code earlier. Fixes: df9b0e30d44c ("neighbor: Add protocol attribute") Cc: David Ahern <dsahern@gmail.com> Signed-off-by: Roman Mashak <mrv@mojatatu.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-04devlink: fix return value after hitting end in region readJakub Kicinski
commit 610a9346c138b9c2c93d38bf5f3728e74ae9cbd5 upstream. Commit d5b90e99e1d5 ("devlink: report 0 after hitting end in region read") fixed region dump, but region read still returns a spurious error: $ devlink region read netdevsim/netdevsim1/dummy snapshot 0 addr 0 len 128 0000000000000000 a6 f4 c4 1c 21 35 95 a6 9d 34 c3 5b 87 5b 35 79 0000000000000010 f3 a0 d7 ee 4f 2f 82 7f c6 dd c4 f6 a5 c3 1b ae 0000000000000020 a4 fd c8 62 07 59 48 03 70 3b c7 09 86 88 7f 68 0000000000000030 6f 45 5d 6d 7d 0e 16 38 a9 d0 7a 4b 1e 1e 2e a6 0000000000000040 e6 1d ae 06 d6 18 00 85 ca 62 e8 7e 11 7e f6 0f 0000000000000050 79 7e f7 0f f3 94 68 bd e6 40 22 85 b6 be 6f b1 0000000000000060 af db ef 5e 34 f0 98 4b 62 9a e3 1b 8b 93 fc 17 devlink answers: Invalid argument 0000000000000070 61 e8 11 11 66 10 a5 f7 b1 ea 8d 40 60 53 ed 12 This is a minimal fix, I'll follow up with a restructuring so we don't have two checks for the same condition. Fixes: fdd41ec21e15 ("devlink: Return right error code in case of errors for region read") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-04cgroup, netclassid: remove double cond_reschedJiri Slaby
commit 526f3d96b8f83b1b13d73bd0b5c79cc2c487ec8e upstream. Commit 018d26fcd12a ("cgroup, netclassid: periodically release file_lock on classid") added a second cond_resched to write_classid indirectly by update_classid_task. Remove the one in write_classid. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Dmitry Yakunin <zeil@yandex-team.ru> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-04net: use indirect call wrappers for skb_copy_datagram_iter()Eric Dumazet
commit 29f3490ba9d2399d3d1b20c4aa74592d92bd4e11 upstream. TCP recvmsg() calls skb_copy_datagram_iter(), which calls an indirect function (cb pointing to simple_copy_to_iter()) for every MSS (fragment) present in the skb. CONFIG_RETPOLINE=y forces a very expensive operation that we can avoid thanks to indirect call wrappers. This patch gives a 13% increase of performance on a single flow, if the bottleneck is the thread reading the TCP socket. Fixes: 950fcaecd5cc ("datagram: consolidate datagram copy to iter helpers") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-01net: revert default NAPI poll timeout to 2 jiffiesKonstantin Khlebnikov
commit a4837980fd9fa4c70a821d11831698901baef56b upstream. For HZ < 1000 timeout 2000us rounds up to 1 jiffy but expires randomly because next timer interrupt could come shortly after starting softirq. For commonly used CONFIG_HZ=1000 nothing changes. Fixes: 7acf8a1e8a28 ("Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning") Reported-by: Dmitry Yakunin <zeil@yandex-team.ru> Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-06-01net: Fix Tx hash bound checkingAmritha Nambiar
commit 6e11d1578fba8d09d03a286740ffcf336d53928c upstream. Fixes the lower and upper bounds when there are multiple TCs and traffic is on the the same TC on the same device. The lower bound is represented by 'qoffset' and the upper limit for hash value is 'qcount + qoffset'. This gives a clean Rx to Tx queue mapping when there are multiple TCs, as the queue indices for upper TCs will be offset by 'qoffset'. v2: Fixed commit description based on comments. Fixes: 1b837d489e06 ("net: Revoke export for __skb_tx_hash, update it to just be static skb_tx_hash") Fixes: eadec877ce9c ("net: Add support for subordinate traffic classes to netdev_pick_tx") Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com> Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} buildPablo Neira Ayuso
commit 2c64605b590edadb3fb46d1ec6badb49e940b479 upstream. net/netfilter/nft_fwd_netdev.c: In function ‘nft_fwd_netdev_eval’: net/netfilter/nft_fwd_netdev.c:32:10: error: ‘struct sk_buff’ has no member named ‘tc_redirected’ pkt->skb->tc_redirected = 1; ^~ net/netfilter/nft_fwd_netdev.c:33:10: error: ‘struct sk_buff’ has no member named ‘tc_from_ingress’ pkt->skb->tc_from_ingress = 1; ^~ To avoid a direct dependency with tc actions from netfilter, wrap the redirect bits around CONFIG_NET_REDIRECT and move helpers to include/linux/skbuff.h. Turn on this toggle from the ifb driver, the only existing client of these bits in the tree. This patch adds skb_set_redirected() that sets on the redirected bit on the skbuff, it specifies if the packet was redirect from ingress and resets the timestamp (timestamp reset was originally missing in the netfilter bugfix). Fixes: bcfabee1afd99484 ("netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress") Reported-by: noreply@ellerman.id.au Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net> [PG: drop wireguard chunk - not present in older v5.2.x codebase.] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21bpf, sockmap: Remove bucket->lock from sock_{hash|map}_freeJohn Fastabend
commit 90db6d772f749e38171d04619a5e3cd8804a6d02 upstream. The bucket->lock is not needed in the sock_hash_free and sock_map_free calls, in fact it is causing a splat due to being inside rcu block. | BUG: sleeping function called from invalid context at net/core/sock.c:2935 | in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 62, name: kworker/0:1 | 3 locks held by kworker/0:1/62: | #0: ffff88813b019748 ((wq_completion)events){+.+.}, at: process_one_work+0x1d7/0x5e0 | #1: ffffc900000abe50 ((work_completion)(&map->work)){+.+.}, at: process_one_work+0x1d7/0x5e0 | #2: ffff8881381f6df8 (&stab->lock){+...}, at: sock_map_free+0x26/0x180 | CPU: 0 PID: 62 Comm: kworker/0:1 Not tainted 5.5.0-04008-g7b083332376e #454 | Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014 | Workqueue: events bpf_map_free_deferred | Call Trace: | dump_stack+0x71/0xa0 | ___might_sleep.cold+0xa6/0xb6 | lock_sock_nested+0x28/0x90 | sock_map_free+0x5f/0x180 | bpf_map_free_deferred+0x58/0x80 | process_one_work+0x260/0x5e0 | worker_thread+0x4d/0x3e0 | kthread+0x108/0x140 | ? process_one_work+0x5e0/0x5e0 | ? kthread_park+0x90/0x90 | ret_from_fork+0x3a/0x50 The reason we have stab->lock and bucket->locks in sockmap code is to handle checking EEXIST in update/delete cases. We need to be careful during an update operation that we check for EEXIST and we need to ensure that the psock object is not in some partial state of removal/insertion while we do this. So both map_update_common and sock_map_delete need to guard from being run together potentially deleting an entry we are checking, etc. But by the time we get to the tear-down code in sock_{ma[|hash}_free we have already disconnected the map and we just did synchronize_rcu() in the line above so no updates/deletes should be in flight. Because of this we can drop the bucket locks from the map free'ing code, noting no update/deletes can be in-flight. Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Reported-by: Jakub Sitnicki <jakub@cloudflare.com> Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/158385850787.30597.8346421465837046618.stgit@john-Precision-5820-Tower Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21tcp: annotate sk->sk_wmem_queued lockless readsEric Dumazet
commit ab4e846a82d0ae00176de19f2db3c5c64f8eb5f2 upstream. For the sake of tcp_poll(), there are few places where we fetch sk->sk_wmem_queued while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. sk_wmem_queued_add() helper is added so that we can in the future convert to ADD_ONCE() or equivalent if/when available. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21tcp: annotate sk->sk_sndbuf lockless readsEric Dumazet
commit e292f05e0df73f9fcc93329663936e1ded97a988 upstream. For the sake of tcp_poll(), there are few places where we fetch sk->sk_sndbuf while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that other transports probably need similar fixes. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21tcp: annotate sk->sk_rcvbuf lockless readsEric Dumazet
commit ebb3b78db7bf842270a46fd4fe7cc45c78fa5ed6 upstream. For the sake of tcp_poll(), there are few places where we fetch sk->sk_rcvbuf while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Note that other transports probably need similar fixes. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21tcp: add rcu protection around tp->fastopen_rskEric Dumazet
commit d983ea6f16b835dcde2ee9a58a1e764ce68bfccc upstream. Both tcp_v4_err() and tcp_v6_err() do the following operations while they do not own the socket lock : fastopen = tp->fastopen_rsk; snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una; The problem is that without appropriate barrier, the compiler might reload tp->fastopen_rsk and trigger a NULL deref. request sockets are protected by RCU, we can simply add the missing annotations and barriers to solve the issue. Fixes: 168a8f58059a ("tcp: TCP Fast Open Server - main code path") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21net: silence KCSAN warnings about sk->sk_backlog.len readsEric Dumazet
commit 70c2655849a25431f31b505a07fe0c861e5e41fb upstream. sk->sk_backlog.len can be written by BH handlers, and read from process contexts in a lockless way. Note the write side should also use WRITE_ONCE() or a variant. We need some agreement about the best way to do this. syzbot reported : BUG: KCSAN: data-race in tcp_add_backlog / tcp_grow_window.isra.0 write to 0xffff88812665f32c of 4 bytes by interrupt on cpu 1: sk_add_backlog include/net/sock.h:934 [inline] tcp_add_backlog+0x4a0/0xcc0 net/ipv4/tcp_ipv4.c:1737 tcp_v4_rcv+0x1aba/0x1bf0 net/ipv4/tcp_ipv4.c:1925 ip_protocol_deliver_rcu+0x51/0x470 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5004 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208 napi_skb_finish net/core/dev.c:5671 [inline] napi_gro_receive+0x28f/0x330 net/core/dev.c:5704 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061 virtnet_receive drivers/net/virtio_net.c:1323 [inline] virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428 napi_poll net/core/dev.c:6352 [inline] net_rx_action+0x3ae/0xa50 net/core/dev.c:6418 read to 0xffff88812665f32c of 4 bytes by task 7292 on cpu 0: tcp_space include/net/tcp.h:1373 [inline] tcp_grow_window.isra.0+0x6b/0x480 net/ipv4/tcp_input.c:413 tcp_event_data_recv+0x68f/0x990 net/ipv4/tcp_input.c:717 tcp_rcv_established+0xbfe/0xf50 net/ipv4/tcp_input.c:5618 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1542 sk_backlog_rcv include/net/sock.h:945 [inline] __release_sock+0x135/0x1e0 net/core/sock.c:2427 release_sock+0x61/0x160 net/core/sock.c:2943 tcp_recvmsg+0x63b/0x1a30 net/ipv4/tcp.c:2181 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:871 [inline] sock_recvmsg net/socket.c:889 [inline] sock_recvmsg+0x92/0xb0 net/socket.c:885 sock_read_iter+0x15f/0x1e0 net/socket.c:967 call_read_iter include/linux/fs.h:1864 [inline] new_sync_read+0x389/0x4f0 fs/read_write.c:414 __vfs_read+0xb1/0xc0 fs/read_write.c:427 vfs_read fs/read_write.c:461 [inline] vfs_read+0x143/0x2c0 fs/read_write.c:446 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 7292 Comm: syz-fuzzer Not tainted 5.3.0+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21devlink: validate length of region addr/lenJakub Kicinski
commit ff3b63b8c299b73ac599b120653b47e275407656 upstream. DEVLINK_ATTR_REGION_CHUNK_ADDR and DEVLINK_ATTR_REGION_CHUNK_LEN lack entries in the netlink policy. Corresponding nla_get_u64()s may read beyond the end of the message. Fixes: 4e54795a27f5 ("devlink: Add support for region snapshot read command") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21devlink: validate length of param valuesJakub Kicinski
commit 8750939b6ad86abc3f53ec8a9683a1cded4a5654 upstream. DEVLINK_ATTR_PARAM_VALUE_DATA may have different types so it's not checked by the normal netlink policy. Make sure the attribute length is what we expect. Fixes: e3b7ca18ad7b ("devlink: Add param set command") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21net: memcg: late association of sock to memcgShakeel Butt
commit d752a4986532cb6305dfd5290a614cde8072769d upstream. If a TCP socket is allocated in IRQ context or cloned from unassociated (i.e. not associated to a memcg) in IRQ context then it will remain unassociated for its whole life. Almost half of the TCPs created on the system are created in IRQ context, so, memory used by such sockets will not be accounted by the memcg. This issue is more widespread in cgroup v1 where network memory accounting is opt-in but it can happen in cgroup v2 if the source socket for the cloning was created in root memcg. To fix the issue, just do the association of the sockets at the accept() time in the process context and then force charge the memory buffer already used and reserved by the socket. Signed-off-by: Shakeel Butt <shakeelb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-21cgroup, netclassid: periodically release file_lock on classid updatingDmitry Yakunin
commit 018d26fcd12a75fb9b5fe233762aa3f2f0854b88 upstream. In our production environment we have faced with problem that updating classid in cgroup with heavy tasks cause long freeze of the file tables in this tasks. By heavy tasks we understand tasks with many threads and opened sockets (e.g. balancers). This freeze leads to an increase number of client timeouts. This patch implements following logic to fix this issue: аfter iterating 1000 file descriptors file table lock will be released thus providing a time gap for socket creation/deletion. Now update is non atomic and socket may be skipped using calls: dup2(oldfd, newfd); close(oldfd); But this case is not typical. Moreover before this patch skip is possible too by hiding socket fd in unix socket buffer. New sockets will be allocated with updated classid because cgroup state is updated before start of the file descriptors iteration. So in common cases this patch has no side effects. Signed-off-by: Dmitry Yakunin <zeil@yandex-team.ru> Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-15Revert "net: dev: introduce support for sch BYPASS for lockless qdisc"Paolo Abeni
commit 379349e9bc3b42b8b2f8f7a03f64a97623fff323 upstream. This reverts commit ba27b4cdaaa66561aaedb2101876e563738d36fe Ahmed reported ouf-of-order issues bisected to commit ba27b4cdaaa6 ("net: dev: introduce support for sch BYPASS for lockless qdisc"). I can't find any working solution other than a plain revert. This will introduce some minor performance regressions for pfifo_fast qdisc. I plan to address them in net-next with more indirect call wrapper boilerplate for qdiscs. Reported-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Fixes: ba27b4cdaaa6 ("net: dev: introduce support for sch BYPASS for lockless qdisc") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-15net: fib_rules: Correctly set table field when table number exceeds 8 bitsJethro Beekman
commit 540e585a79e9d643ede077b73bcc7aa2d7b4d919 upstream. In 709772e6e06564ed94ba740de70185ac3d792773, RT_TABLE_COMPAT was added to allow legacy software to deal with routing table numbers >= 256, but the same change to FIB rule queries was overlooked. Signed-off-by: Jethro Beekman <jethro@fortanix.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-15bpf: Return -EBADRQC for invalid map type in __bpf_tx_xdp_mapLi RongQing
commit 0a29275b6300f39f78a87f2038bbfe5bdbaeca47 upstream. A negative value should be returned if map->map_type is invalid although that is impossible now, but if we run into such situation in future, then xdpbuff could be leaked. Daniel Borkmann suggested: -EBADRQC should be returned to stay consistent with generic XDP for the tracepoint output and not to be confused with -EOPNOTSUPP from other locations like dev_map_enqueue() when ndo_xdp_xmit is missing and such. Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/1578618277-18085-1-git-send-email-lirongqing@baidu.com Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-15core: Don't skip generic XDP program execution for cloned SKBsToke Høiland-Jørgensen
commit ad1e03b2b3d4430baaa109b77bc308dc73050de3 upstream. The current generic XDP handler skips execution of XDP programs entirely if an SKB is marked as cloned. This leads to some surprising behaviour, as packets can end up being cloned in various ways, which will make an XDP program not see all the traffic on an interface. This was discovered by a simple test case where an XDP program that always returns XDP_DROP is installed on a veth device. When combining this with the Scapy packet sniffer (which uses an AF_PACKET) socket on the sending side, SKBs reliably end up in the cloned state, causing them to be passed through to the receiving interface instead of being dropped. A minimal reproducer script for this is included below. This patch fixed the issue by simply triggering the existing linearisation code for cloned SKBs instead of skipping the XDP program execution. This behaviour is in line with the behaviour of the native XDP implementation for the veth driver, which will reallocate and copy the SKB data if the SKB is marked as shared. Reproducer Python script (requires BCC and Scapy): from scapy.all import TCP, IP, Ether, sendp, sniff, AsyncSniffer, Raw, UDP from bcc import BPF import time, sys, subprocess, shlex SKB_MODE = (1 << 1) DRV_MODE = (1 << 2) PYTHON=sys.executable def client(): time.sleep(2) # Sniffing on the sender causes skb_cloned() to be set s = AsyncSniffer() s.start() for p in range(10): sendp(Ether(dst="aa:aa:aa:aa:aa:aa", src="cc:cc:cc:cc:cc:cc")/IP()/UDP()/Raw("Test"), verbose=False) time.sleep(0.1) s.stop() return 0 def server(mode): prog = BPF(text="int dummy_drop(struct xdp_md *ctx) {return XDP_DROP;}") func = prog.load_func("dummy_drop", BPF.XDP) prog.attach_xdp("a_to_b", func, mode) time.sleep(1) s = sniff(iface="a_to_b", count=10, timeout=15) if len(s): print(f"Got {len(s)} packets - should have gotten 0") return 1 else: print("Got no packets - as expected") return 0 if len(sys.argv) < 2: print(f"Usage: {sys.argv[0]} <skb|drv>") sys.exit(1) if sys.argv[1] == "client": sys.exit(client()) elif sys.argv[1] == "server": mode = SKB_MODE if sys.argv[2] == 'skb' else DRV_MODE sys.exit(server(mode)) else: try: mode = sys.argv[1] if mode not in ('skb', 'drv'): print(f"Usage: {sys.argv[0]} <skb|drv>") sys.exit(1) print(f"Running in {mode} mode") for cmd in [ 'ip netns add netns_a', 'ip netns add netns_b', 'ip -n netns_a link add a_to_b type veth peer name b_to_a netns netns_b', # Disable ipv6 to make sure there's no address autoconf traffic 'ip netns exec netns_a sysctl -qw net.ipv6.conf.a_to_b.disable_ipv6=1', 'ip netns exec netns_b sysctl -qw net.ipv6.conf.b_to_a.disable_ipv6=1', 'ip -n netns_a link set dev a_to_b address aa:aa:aa:aa:aa:aa', 'ip -n netns_b link set dev b_to_a address cc:cc:cc:cc:cc:cc', 'ip -n netns_a link set dev a_to_b up', 'ip -n netns_b link set dev b_to_a up']: subprocess.check_call(shlex.split(cmd)) server = subprocess.Popen(shlex.split(f"ip netns exec netns_a {PYTHON} {sys.argv[0]} server {mode}")) client = subprocess.Popen(shlex.split(f"ip netns exec netns_b {PYTHON} {sys.argv[0]} client")) client.wait() server.wait() sys.exit(server.returncode) finally: subprocess.run(shlex.split("ip netns delete netns_a")) subprocess.run(shlex.split("ip netns delete netns_b")) Fixes: d445516966dc ("net: xdp: support xdp generic on virtual devices") Reported-by: Stepan Horacek <shoracek@redhat.com> Suggested-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-04bpf, sockmap: Check update requirements after lockingLorenz Bauer
commit 85b8ac01a421791d66c3a458a7f83cfd173fe3fa upstream. It's currently possible to insert sockets in unexpected states into a sockmap, due to a TOCTTOU when updating the map from a syscall. sock_map_update_elem checks that sk->sk_state == TCP_ESTABLISHED, locks the socket and then calls sock_map_update_common. At this point, the socket may have transitioned into another state, and the earlier assumptions don't hold anymore. Crucially, it's conceivable (though very unlikely) that a socket has become unhashed. This breaks the sockmap's assumption that it will get a callback via sk->sk_prot->unhash. Fix this by checking the (fixed) sk_type and sk_protocol without the lock, followed by a locked check of sk_state. Unfortunately it's not possible to push the check down into sock_(map|hash)_update_common, since BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB run before the socket has transitioned from TCP_SYN_RECV into TCP_ESTABLISHED. Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20200207103713.28175-1-lmb@cloudflare.com Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2020-05-04bpf: Improve bucket_log calculation logicMartin KaFai Lau
commit 88d6f130e5632bbf419a2e184ec7adcbe241260b upstream. It was reported that the max_t, ilog2, and roundup_pow_of_two macros have exponential effects on the number of states in the sparse checker. This patch breaks them up by calculating the "nbuckets" first so that the "bucket_log" only needs to take ilog2(). In addition, Linus mentioned: Patch looks good, but I'd like to point out that it's not just sparse. You can see it with a simple make net/core/bpf_sk_storage.i grep 'smap->bucket_log = ' net/core/bpf_sk_storage.i | wc and see the end result: 1 365071 2686974 That's one line (the assignment line) that is 2,686,974 characters in length. Now, sparse does happen to react particularly badly to that (I didn't look to why, but I suspect it's just that evaluating all the types that don't actually ever end up getting used ends up being much more expensive than it should be), but I bet it's not good for gcc either. Fixes: 6ac99e8f23d4 ("bpf: Introduce bpf sk local storage") Reported-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Link: https://lore.kernel.org/bpf/20200207081810.3918919-1-kafai@fb.com Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>