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path: root/drivers/md/dm-crypt.c
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2014-12-08Merge tag 'dm-3.19-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - Significant DM thin-provisioning performance improvements to meet performance requirements that were requested by the Gluster distributed filesystem. Specifically, dm-thinp now takes care to aggregate IO that will be issued to the same thinp block before issuing IO to the underlying devices. This really helps improve performance on HW RAID6 devices that have a writeback cache because it avoids RMW in the HW RAID controller. - Some stable fixes: fix leak in DM bufio if integrity profiles were enabled, use memzero_explicit in DM crypt to avoid any potential for information leak, and a DM cache fix to properly mark a cache block dirty if it was promoted to the cache via the overwrite optimization. - A few simple DM persistent data library fixes - DM cache multiqueue policy block promotion improvements. - DM cache discard improvements that take advantage of range (multiblock) discard support in the DM bio-prison. This allows for much more efficient bulk discard processing (e.g. when mkfs.xfs discards the entire device). - Some small optimizations in DM core and RCU deference cleanups - DM core changes to suspend/resume code to introduce the new internal suspend/resume interface that the DM thin-pool target now uses to suspend/resume active thin devices when the thin-pool must suspend/resume. This avoids forcing userspace to track all active thin volumes in a thin-pool when the thin-pool is suspended for the purposes of metadata or data space resize. * tag 'dm-3.19-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (49 commits) dm crypt: use memzero_explicit for on-stack buffer dm space map metadata: fix sm_bootstrap_get_count() dm space map metadata: fix sm_bootstrap_get_nr_blocks() dm bufio: fix memleak when using a dm_buffer's inline bio dm cache: fix spurious cell_defer when dealing with partial block at end of device dm cache: dirty flag was mistakenly being cleared when promoting via overwrite dm cache: only use overwrite optimisation for promotion when in writeback mode dm cache: discard block size must be a multiple of cache block size dm cache: fix a harmless race when working out if a block is discarded dm cache: when reloading a discard bitset allow for a different discard block size dm cache: fix some issues with the new discard range support dm array: if resizing the array is a noop set the new root to the old one dm: use rcu_dereference_protected instead of rcu_dereference dm thin: fix pool_io_hints to avoid looking at max_hw_sectors dm thin: suspend/resume active thin devices when reloading thin-pool dm: enhance internal suspend and resume interface dm thin: do not allow thin device activation while pool is suspended dm: add presuspend_undo hook to target_type dm: return earlier from dm_blk_ioctl if target doesn't implement .ioctl dm thin: remove stale 'trim' message in block comment above pool_message ...
2014-12-02dm crypt: use memzero_explicit for on-stack bufferMilan Broz
Use memzero_explicit to cleanup sensitive data allocated on stack to prevent the compiler from optimizing and removing memset() calls. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2014-10-14crypto, dm: LLVMLinux: Remove VLAIS usage from dm-cryptJan-Simon Möller
Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99 compliant equivalent. This patch allocates the appropriate amount of memory using a char array using the SHASH_DESC_ON_STACK macro. The new code can be compiled with both gcc and clang. Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de> Signed-off-by: Behan Webster <behanw@converseincode.com> Reviewed-by: Mark Charlebois <charlebm@gmail.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Cc: pageexec@freemail.hu Cc: gmazyland@gmail.com Cc: "David S. Miller" <davem@davemloft.net>
2014-08-28dm crypt: fix access beyond the end of allocated spaceMikulas Patocka
The DM crypt target accesses memory beyond allocated space resulting in a crash on 32 bit x86 systems. This bug is very old (it dates back to 2.6.25 commit 3a7f6c990ad04 "dm crypt: use async crypto"). However, this bug was masked by the fact that kmalloc rounds the size up to the next power of two. This bug wasn't exposed until 3.17-rc1 commit 298a9fa08a ("dm crypt: use per-bio data"). By switching to using per-bio data there was no longer any padding beyond the end of a dm-crypt allocated memory block. To minimize allocation overhead dm-crypt puts several structures into one block allocated with kmalloc. The block holds struct ablkcipher_request, cipher-specific scratch pad (crypto_ablkcipher_reqsize(any_tfm(cc))), struct dm_crypt_request and an initialization vector. The variable dmreq_start is set to offset of struct dm_crypt_request within this memory block. dm-crypt allocates the block with this size: cc->dmreq_start + sizeof(struct dm_crypt_request) + cc->iv_size. When accessing the initialization vector, dm-crypt uses the function iv_of_dmreq, which performs this calculation: ALIGN((unsigned long)(dmreq + 1), crypto_ablkcipher_alignmask(any_tfm(cc)) + 1). dm-crypt allocated "cc->iv_size" bytes beyond the end of dm_crypt_request structure. However, when dm-crypt accesses the initialization vector, it takes a pointer to the end of dm_crypt_request, aligns it, and then uses it as the initialization vector. If the end of dm_crypt_request is not aligned on a crypto_ablkcipher_alignmask(any_tfm(cc)) boundary the alignment causes the initialization vector to point beyond the allocated space. Fix this bug by calculating the variable iv_size_padding and adding it to the allocated size. Also correct the alignment of dm_crypt_request. struct dm_crypt_request is specific to dm-crypt (it isn't used by the crypto subsystem at all), so it is aligned on __alignof__(struct dm_crypt_request). Also align per_bio_data_size on ARCH_KMALLOC_MINALIGN, so that it is aligned as if the block was allocated with kmalloc. Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl> Tested-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-08-01dm crypt: use per-bio dataMikulas Patocka
Change dm-crypt so that it uses auxiliary data allocated with the bio. Dm-crypt requires two allocations per request - struct dm_crypt_io and struct ablkcipher_request (with other data appended to it). It previously only used mempool allocations. Some requests may require more dm_crypt_ios and ablkcipher_requests, however most requests need just one of each of these two structures to complete. This patch changes it so that the first dm_crypt_io and ablkcipher_request are allocated with the bio (using target per_bio_data_size option). If the request needs additional values, they are allocated from the mempool. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-07-10dm crypt, dm zero: update author name following legal name changeJana Saout
Signed-off-by: Jana Saout <jana@saout.de> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-05-14dm crypt: fix cpu hotplug crash by removing per-cpu structureMikulas Patocka
The DM crypt target used per-cpu structures to hold pointers to a ablkcipher_request structure. The code assumed that the work item keeps executing on a single CPU, so it didn't use synchronization when accessing this structure. If a CPU is disabled by writing 0 to /sys/devices/system/cpu/cpu*/online, the work item could be moved to another CPU. This causes dm-crypt crashes, like the following, because the code starts using an incorrect ablkcipher_request: smpboot: CPU 7 is now offline BUG: unable to handle kernel NULL pointer dereference at 0000000000000130 IP: [<ffffffffa1862b3d>] crypt_convert+0x12d/0x3c0 [dm_crypt] ... Call Trace: [<ffffffffa1864415>] ? kcryptd_crypt+0x305/0x470 [dm_crypt] [<ffffffff81062060>] ? finish_task_switch+0x40/0xc0 [<ffffffff81052a28>] ? process_one_work+0x168/0x470 [<ffffffff8105366b>] ? worker_thread+0x10b/0x390 [<ffffffff81053560>] ? manage_workers.isra.26+0x290/0x290 [<ffffffff81058d9f>] ? kthread+0xaf/0xc0 [<ffffffff81058cf0>] ? kthread_create_on_node+0x120/0x120 [<ffffffff813464ac>] ? ret_from_fork+0x7c/0xb0 [<ffffffff81058cf0>] ? kthread_create_on_node+0x120/0x120 Fix this bug by removing the per-cpu definition. The structure ablkcipher_request is accessed via a pointer from convert_context. Consequently, if the work item is rescheduled to a different CPU, the thread still uses the same ablkcipher_request. This change may undermine performance improvements intended by commit c0297721 ("dm crypt: scale to multiple cpus") on select hardware. In practice no performance difference was observed on recent hardware. But regardless, correctness is more important than performance. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: stable@vger.kernel.org
2013-11-23block: Convert drivers to immutable biovecsKent Overstreet
Now that we've got a mechanism for immutable biovecs - bi_iter.bi_bvec_done - we need to convert drivers to use primitives that respect it instead of using the bvec array directly. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: NeilBrown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: dm-devel@redhat.com
2013-11-23block: Abstract out bvec iteratorKent Overstreet
Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-11-15tree-wide: use reinit_completion instead of INIT_COMPLETIONWolfram Sang
Use this new function to make code more comprehensible, since we are reinitialzing the completion, not initializing. [akpm@linux-foundation.org: linux-next resyncs] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13) Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-09dm crypt: add TCW IV mode for old CBC TCRYPT containersMilan Broz
dm-crypt can already activate TCRYPT (TrueCrypt compatible) containers in LRW or XTS block encryption mode. TCRYPT containers prior to version 4.1 use CBC mode with some additional tweaks, this patch adds support for these containers. This new mode is implemented using special IV generator named TCW (TrueCrypt IV with whitening). TCW IV only supports containers that are encrypted with one cipher (Tested with AES, Twofish, Serpent, CAST5 and TripleDES). While this mode is legacy and is known to be vulnerable to some watermarking attacks (e.g. revealing of hidden disk existence) it can still be useful to activate old containers without using 3rd party software or for independent forensic analysis of such containers. (Both the userspace and kernel code is an independent implementation based on the format documentation and it completely avoids use of original source code.) The TCW IV generator uses two additional keys: Kw (whitening seed, size is always 16 bytes - TCW_WHITENING_SIZE) and Kiv (IV seed, size is always the IV size of the selected cipher). These keys are concatenated at the end of the main encryption key provided in mapping table. While whitening is completely independent from IV, it is implemented inside IV generator for simplification. The whitening value is always 16 bytes long and is calculated per sector from provided Kw as initial seed, xored with sector number and mixed with CRC32 algorithm. Resulting value is xored with ciphertext sector content. IV is calculated from the provided Kiv as initial IV seed and xored with sector number. Detailed calculation can be found in the Truecrypt documentation for version < 4.1 and will also be described on dm-crypt site, see: http://code.google.com/p/cryptsetup/wiki/DMCrypt The experimental support for activation of these containers is already present in git devel brach of cryptsetup. Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-11-09dm crypt: properly handle extra key string in initializationMilan Broz
Some encryption modes use extra keys (e.g. loopAES has IV seed) which are not used in block cipher initialization but are part of key string in table constructor. This patch adds an additional field which describes the length of the extra key(s) and substracts it before real key encryption setting. The key_size always includes the size, in bytes, of the key provided in mapping table. The key_parts describes how many parts (usually keys) are contained in the whole key buffer. And key_extra_size contains size in bytes of additional keys part (this number of bytes must be subtracted because it is processed by the IV generator). | K1 | K2 | .... | K64 | Kiv | |----------- key_size ----------------- | | |-key_extra_size-| | [64 keys] | [1 key] | => key_parts = 65 Example where key string contains main key K, whitening key Kw and IV seed Kiv: | K | Kiv | Kw | |--------------- key_size --------------| | |-----key_extra_size------| | [1 key] | [1 key] | [1 key] | => key_parts = 3 Because key_extra_size is calculated during IV mode setting, key initialization is moved after this step. For now, this change has no effect to supported modes (thanks to ilog2 rounding) but it is required by the following patch. Also, fix a sparse warning in crypt_iv_lmk_one(). Signed-off-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-08-23dm: stop using WQ_NON_REENTRANTTejun Heo
dbf2576e37 ("workqueue: make all workqueues non-reentrant") made WQ_NON_REENTRANT no-op and the flag is going away. Remove its usages. This patch doesn't introduce any behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2013-03-23block: Convert some code to bio_for_each_segment_all()Kent Overstreet
More prep work for immutable bvecs: A few places in the code were either open coding or using the wrong version - fix. After we introduce the bvec iter, it'll no longer be possible to modify the biovec through bio_for_each_segment_all() - it doesn't increment a pointer to the current bvec, you pass in a struct bio_vec (not a pointer) which is updated with what the current biovec would be (taking into account bi_bvec_done and bi_size). So because of that it's more worthwhile to be consistent about bio_for_each_segment()/bio_for_each_segment_all() usage. Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Jens Axboe <axboe@kernel.dk> CC: NeilBrown <neilb@suse.de> CC: Alasdair Kergon <agk@redhat.com> CC: dm-devel@redhat.com CC: Alexander Viro <viro@zeniv.linux.org.uk>
2013-03-01dm: rename request variables to biosAlasdair G Kergon
Use 'bio' in the name of variables and functions that deal with bios rather than 'request' to avoid confusion with the normal block layer use of 'request'. No functional changes. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-01dm: fix truncated status stringsMikulas Patocka
Avoid returning a truncated table or status string instead of setting the DM_BUFFER_FULL_FLAG when the last target of a table fills the buffer. When processing a table or status request, the function retrieve_status calls ti->type->status. If ti->type->status returns non-zero, retrieve_status assumes that the buffer overflowed and sets DM_BUFFER_FULL_FLAG. However, targets don't return non-zero values from their status method on overflow. Most targets returns always zero. If a buffer overflow happens in a target that is not the last in the table, it gets noticed during the next iteration of the loop in retrieve_status; but if a buffer overflow happens in the last target, it goes unnoticed and erroneously truncated data is returned. In the current code, the targets behave in the following way: * dm-crypt returns -ENOMEM if there is not enough space to store the key, but it returns 0 on all other overflows. * dm-thin returns errors from the status method if a disk error happened. This is incorrect because retrieve_status doesn't check the error code, it assumes that all non-zero values mean buffer overflow. * all the other targets always return 0. This patch changes the ti->type->status function to return void (because most targets don't use the return code). Overflow is detected in retrieve_status: if the status method fills up the remaining space completely, it is assumed that buffer overflow happened. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-12-21dm: remove map_infoMikulas Patocka
This patch removes map_info from bio-based device mapper targets. map_info is still used for request-based targets. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-09-09block: Add bio_clone_bioset(), bio_clone_kmalloc()Kent Overstreet
Previously, there was bio_clone() but it only allocated from the fs bio set; as a result various users were open coding it and using __bio_clone(). This changes bio_clone() to become bio_clone_bioset(), and then we add bio_clone() and bio_clone_kmalloc() as wrappers around it, making use of the functionality the last patch adedd. This will also help in a later patch changing how bio cloning works. Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Jens Axboe <axboe@kernel.dk> CC: NeilBrown <neilb@suse.de> CC: Alasdair Kergon <agk@redhat.com> CC: Boaz Harrosh <bharrosh@panasas.com> CC: Jeff Garzik <jeff@garzik.org> Acked-by: Jeff Garzik <jgarzik@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-09-09block: Generalized bio pool freeingKent Overstreet
With the old code, when you allocate a bio from a bio pool you have to implement your own destructor that knows how to find the bio pool the bio was originally allocated from. This adds a new field to struct bio (bi_pool) and changes bio_alloc_bioset() to use it. This makes various bio destructors unnecessary, so they're then deleted. v6: Explain the temporary if statement in bio_put Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Jens Axboe <axboe@kernel.dk> CC: NeilBrown <neilb@suse.de> CC: Alasdair Kergon <agk@redhat.com> CC: Nicholas Bellinger <nab@linux-iscsi.org> CC: Lars Ellenberg <lars.ellenberg@linbit.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-07-27dm thin: commit before gathering statusAlasdair G Kergon
Commit outstanding metadata before returning the status for a dm thin pool so that the numbers reported are as up-to-date as possible. The commit is not performed if the device is suspended or if the DM_NOFLUSH_FLAG is supplied by userspace and passed to the target through a new 'status_flags' parameter in the target's dm_status_fn. The userspace dmsetup tool will support the --noflush flag with the 'dmsetup status' and 'dmsetup wait' commands from version 1.02.76 onwards. Tested-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27dm: use bool bitfields in struct dm_targetAlasdair G Kergon
Use boolean bit fields for flags in struct dm_target. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27dm crypt: rename struct convert_context sector fieldMikulas Patocka
Rename sector to cc_sector in dm-crypt's convert_context struct. This is preparation for a future patch that merges dm_io and convert_context which both have a "sector" field. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27dm crypt: store crypt_config instead of dm_target structAlasdair G Kergon
Store the crypt_config struct pointer directly in struct dm_crypt_io instead of the dm_target struct pointer. Target information is never used - only target->private is referenced, thus we can change it to point directly to struct crypt_config. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27dm crypt: move cipher data out of per_cpu structMikulas Patocka
Move static dm-crypt cipher data out of per-cpu structure. Cipher information is static, so it does not have to be in a per-cpu structure. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27dm crypt: rename pending fieldMikulas Patocka
There are two dm crypt structures that have a field called "pending". This patch renames them to "cc_pending" and "io_pending" to reduce confusion and ease searching the code. Also remove unnecessary initialisation of r in crypt_convert_block(). Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27dm: replace simple_strtoulmajianpeng
Replace obsolete simple_strtoul() with kstrtou8/kstrtouint. Signed-off-by: majianpeng <majianpeng@gmail.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28dm: reject trailing characters in sccanf inputMikulas Patocka
Device mapper uses sscanf to convert arguments to numbers. The problem is that the way we use it ignores additional unmatched characters in the scanned string. For example, this `if (sscanf(string, "%d", &number) == 1)' will match a number, but also it will match number with some garbage appended, like "123abc". As a result, device mapper accepts garbage after some numbers. For example the command `dmsetup create vg1-new --table "0 16384 linear 254:1bla 34816bla"' will pass without an error. This patch fixes all sscanf uses in device mapper. It appends "%c" with a pointer to a dummy character variable to every sscanf statement. The construct `if (sscanf(string, "%d%c", &number, &dummy) == 1)' succeeds only if string is a null-terminated number (optionally preceded by some whitespace characters). If there is some character appended after the number, sscanf matches "%c", writes the character to the dummy variable and returns 2. We check the return value for 1 and consequently reject numbers with some garbage appended. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28dm crypt: add missing error handlingMikulas Patocka
Always set io->error to -EIO when an error is detected in dm-crypt. There were cases where an error code would be set only if we finish processing the last sector. If there were other encryption operations in flight, the error would be ignored and bio would be returned with success as if no error happened. This bug is present in kcryptd_crypt_write_convert, kcryptd_crypt_read_convert and kcryptd_async_done. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@kernel.org Reviewed-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28dm crypt: fix mempool deadlockMikulas Patocka
This patch fixes a possible deadlock in dm-crypt's mempool use. Currently, dm-crypt reserves a mempool of MIN_BIO_PAGES reserved pages. It allocates first MIN_BIO_PAGES with non-failing allocation (the allocation cannot fail and waits until the mempool is refilled). Further pages are allocated with different gfp flags that allow failing. Because allocations may be done in parallel, this code can deadlock. Example: There are two processes, each tries to allocate MIN_BIO_PAGES and the processes run simultaneously. It may end up in a situation where each process allocates (MIN_BIO_PAGES / 2) pages. The mempool is exhausted. Each process waits for more pages to be freed to the mempool, which never happens. To avoid this deadlock scenario, this patch changes the code so that only the first page is allocated with non-failing gfp mask. Allocation of further pages may fail. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@kernel.org Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-20dm: remove the second argument of k[un]map_atomic()Cong Wang
Acked-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Cong Wang <amwang@redhat.com>
2011-09-25dm crypt: always disable discard_zeroes_dataMilan Broz
If optional discard support in dm-crypt is enabled, discards requests bypass the crypt queue and blocks of the underlying device are discarded. For the read path, discarded blocks are handled the same as normal ciphertext blocks, thus decrypted. So if the underlying device announces discarded regions return zeroes, dm-crypt must disable this flag because after decryption there is just random noise instead of zeroes. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-08-02dm crypt: optionally support discard requestsMilan Broz
Add optional parameter field to dmcrypt table and support "allow_discards" option. Discard requests bypass crypt queue processing. Bio is simple remapped to underlying device. Note that discard will be never enabled by default because of security consequences. It is up to the administrator to enable it for encrypted devices. (Note that userspace cryptsetup does not understand new optional parameters yet. Support for this will come later. Until then, you should use 'dmsetup' to enable and disable this.) Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-08-02dm table: share target argument parsing functionsMike Snitzer
Move multipath target argument parsing code into dm-table so other targets can share it. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-08-02dm: suppress endian warningsAlasdair G Kergon
Suppress sparse warnings about cpu_to_le32() by using __le32 types for on-disk data etc. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-07-26atomic: use <linux/atomic.h>Arun Sharma
This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dmLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: dm stripe: implement merge method dm mpath: allow table load with no priority groups dm mpath: fail message ioctl if specified path is not valid dm ioctl: add flag to wipe buffers for secure data dm ioctl: prepare for crypt key wiping dm crypt: wipe keys string immediately after key is set dm: add flakey target dm: fix opening log and cow devices for read only tables
2011-03-24dm crypt: wipe keys string immediately after key is setMilan Broz
Always wipe the original copy of the key after processing it in crypt_set_key(). Signed-off-by: Milan Broz <mbroz@redhat.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-03-10block: remove per-queue pluggingJens Axboe
Code has been converted over to the new explicit on-stack plugging, and delay users have been converted to use the new API for that. So lets kill off the old plugging along with aops->sync_page(). Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-13dm crypt: add loop aes iv generatorMilan Broz
This patch adds a compatible implementation of the block chaining mode used by the Loop-AES block device encryption system (http://loop-aes.sourceforge.net/) designed by Jari Ruusu. It operates on full 512 byte sectors and uses CBC with an IV derived from the sector number, the data and optionally extra IV seed. This means that after CBC decryption the first block of sector must be tweaked according to decrypted data. Loop-AES can use three encryption schemes: version 1: is plain aes-cbc mode (already compatible) version 2: uses 64 multikey scheme with own IV generator version 3: the same as version 2 with additional IV seed (it uses 65 keys, last key is used as IV seed) The IV generator is here named lmk (Loop-AES multikey) and for the cipher specification looks like: aes:64-cbc-lmk Version 2 and 3 is recognised according to length of provided multi-key string (which is just hexa encoded "raw key" used in original Loop-AES ioctl). Configuration of the device and decoding key string will be done in userspace (cryptsetup). (Loop-AES stores keys in gpg encrypted file, raw keys are output of simple hashing of lines in this file). Based on an implementation by Max Vozeler: http://article.gmane.org/gmane.linux.kernel.cryptoapi/3752/ Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> CC: Max Vozeler <max@hinterhof.net>
2011-01-13dm crypt: add multi key capabilityMilan Broz
This patch adds generic multikey handling to be used in following patch for Loop-AES mode compatibility. This patch extends mapping table to optional keycount and implements generic multi-key capability. With more keys defined the <key> string is divided into several <keycount> sections and these are used for tfms. The tfm is used according to sector offset (sector 0->tfm[0], sector 1->tfm[1], sector N->tfm[N modulo keycount]) (only power of two values supported for keycount here). Because of tfms per-cpu allocation, this mode can be take a lot of memory on large smp systems. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: Max Vozeler <max@hinterhof.net>
2011-01-13dm crypt: add post iv call to iv generatorMilan Broz
IV (initialisation vector) can in principle depend not only on sector but also on plaintext data (or other attributes). Change IV generator interface to work directly with dmreq structure to allow such dependence in generator. Also add post() function which is called after the crypto operation. This allows tricky modification of decrypted data or IV internals. In asynchronous mode the post() can be called after ctx->sector count was increased so it is needed to add iv_sector copy directly to dmreq structure. (N.B. dmreq always include only one sector in scatterlists) Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm crypt: use io thread for reads only if mempool exhaustedMilan Broz
If there is enough memory, code can directly submit bio instead queing this operation in separate thread. Try to alloc bio clone with GFP_NOWAIT and only if it fails use separate queue (map function cannot block here). Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm crypt: scale to multiple cpusAndi Kleen
Currently dm-crypt does all the encryption work for a single dm-crypt mapping in a single workqueue. This does not scale well when multiple CPUs are submitting IO at a high rate. The single CPU running the single thread cannot keep up with the encryption and encrypted IO performance tanks. This patch changes the crypto workqueue to be per CPU. This means that as long as the IO submitter (or the interrupt target CPUs for reads) runs on different CPUs the encryption work will be also parallel. To avoid a bottleneck on the IO worker I also changed those to be per-CPU threads. There is still some shared data, so I suspect some bouncing cache lines. But I haven't done a detailed study on that yet. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm crypt: simplify compatible table outputMilan Broz
Rename cc->cipher_mode to cc->cipher_string and store the whole of the cipher information so it can easily be printed when processing the DM_DEV_STATUS ioctl. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm crypt: set key size earlyMilan Broz
Simplify key size verification (hexadecimal string) and set key size early in constructor. (Patch required by later changes.) Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-09-10dm: implement REQ_FLUSH/FUA support for bio-based dmTejun Heo
This patch converts bio-based dm to support REQ_FLUSH/FUA instead of now deprecated REQ_HARDBARRIER. * -EOPNOTSUPP handling logic dropped. * Preflush is handled as before but postflush is dropped and replaced with passing down REQ_FUA to member request_queues. This replaces one array wide cache flush w/ member specific FUA writes. * __split_and_process_bio() now calls __clone_and_map_flush() directly for flushes and guarantees all FLUSH bio's going to targets are zero ` length. * It's now guaranteed that all FLUSH bio's which are passed onto dm targets are zero length. bio_empty_barrier() tests are replaced with REQ_FLUSH tests. * Empty WRITE_BARRIERs are replaced with WRITE_FLUSHes. * Dropped unlikely() around REQ_FLUSH tests. Flushes are not unlikely enough to be marked with unlikely(). * Block layer now filters out REQ_FLUSH/FUA bio's if the request_queue doesn't support cache flushing. Advertise REQ_FLUSH | REQ_FUA capability. * Request based dm isn't converted yet. dm_init_request_based_queue() resets flush support to 0 for now. To avoid disturbing request based dm code, dm->flush_error is added for bio based dm while requested based dm continues to use dm->barrier_error. Lightly tested linear, stripe, raid1, snap and crypt targets. Please proceed with caution as I'm not familiar with the code base. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: dm-devel@redhat.com Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-12dm: use dm_target_offset macroAlasdair G Kergon
Use new dm_target_offset() macro to avoid most references to ti->begin in dm targets. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12dm crypt: simplify crypt_ctrMilan Broz
Allocate cipher strings indpendently of struct crypt_config and move cipher parsing and allocation into a separate function to prepare for supporting the cryptoapi format e.g. "xts(aes)". No functional change in this patch. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12dm crypt: simplify crypt_config destruction logicMilan Broz
Use just one label and reuse common destructor for crypt target. Parse remaining argv arguments in logic order. Also do not ignore error values from IV init and set key functions. No functional change in this patch except changed return codes based on above. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12dm crypt: use kstrdupJulia Lawall
Use kstrdup when the goal of an allocation is copy a string into the allocated region. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression from,to; expression flag,E1,E2; statement S; @@ - to = kmalloc(strlen(from) + 1,flag); + to = kstrdup(from, flag); ... when != \(from = E1 \| to = E1 \) if (to==NULL || ...) S ... when != \(from = E2 \| to = E2 \) - strcpy(to, from); // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Alasdair G Kergon <agk@redhat.com>