kernel/linux.git/drivers/md/dm-crypt.c, branch v5.9.12

dm crypt: Initialize crypto wait structures

2020-09-01T20:41:57+00:00

Use the DECLARE_CRYPTO_WAIT() macro to properly initialize the crypto wait structures declared on stack before their use with crypto_wait_req(). Fixes: 39d13a1ac41d ("dm crypt: reuse eboiv skcipher for IV generation") Fixes: bbb1658461ac ("dm crypt: Implement Elephant diffuser for Bitlocker compatibility") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal Signed-off-by: Mike Snitzer

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva

Merge tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2020-08-07T20:08:09+00:00

Pull device mapper updates from Mike Snitzer: - DM multipath locking fixes around m->flags tests and improvements to bio-based code so that it follows patterns established by request-based code. - Request-based DM core improvement to eliminate unnecessary call to blk_mq_queue_stopped(). - Add "panic_on_corruption" error handling mode to DM verity target. - DM bufio fix to to perform buffer cleanup from a workqueue rather than wait for IO in reclaim context from shrinker. - DM crypt improvement to optionally avoid async processing via workqueues for reads and/or writes -- via "no_read_workqueue" and "no_write_workqueue" features. This more direct IO processing improves latency and throughput with faster storage. Avoiding workqueue IO submission for writes (DM_CRYPT_NO_WRITE_WORKQUEUE) is a requirement for adding zoned block device support to DM crypt. - Add zoned block device support to DM crypt. Makes use of DM_CRYPT_NO_WRITE_WORKQUEUE and a new optional feature (DM_CRYPT_WRITE_INLINE) that allows write completion to wait for encryption to complete. This allows write ordering to be preserved, which is needed for zoned block devices. - Fix DM ebs target's check for REQ_OP_FLUSH. - Fix DM core's report zones support to not report more zones than were requested. - A few small compiler warning fixes. - DM dust improvements to return output directly to the user rather than require they scrape the system log for output. * tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm: don't call report zones for more than the user requested dm ebs: Fix incorrect checking for REQ_OP_FLUSH dm init: Set file local variable static dm ioctl: Fix compilation warning dm raid: Remove empty if statement dm verity: Fix compilation warning dm crypt: Enable zoned block device support dm crypt: add flags to optionally bypass kcryptd workqueues dm bufio: do buffer cleanup from a workqueue dm rq: don't call blk_mq_queue_stopped() in dm_stop_queue() dm dust: add interface to list all badblocks dm dust: report some message results directly back to user dm verity: add "panic_on_corruption" error handling mode dm mpath: use double checked locking in fast path dm mpath: rename current_pgpath to pgpath in multipath_prepare_ioctl dm mpath: rework __map_bio() dm mpath: factor out multipath_queue_bio dm mpath: push locking down to must_push_back_rq() dm mpath: take m->lock spinlock when testing QUEUE_IF_NO_PATH dm mpath: changes from initial m->flags locking audit

mm, treewide: rename kzfree() to kfree_sensitive()

2020-08-07T18:33:22+00:00

As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches Signed-off-by: Waiman Long Signed-off-by: Andrew Morton Acked-by: David Howells Acked-by: Michal Hocko Acked-by: Johannes Weiner Cc: Jarkko Sakkinen Cc: James Morris Cc: "Serge E. Hallyn" Cc: Joe Perches Cc: Matthew Wilcox Cc: David Rientjes Cc: Dan Carpenter Cc: "Jason A . Donenfeld" Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds

Merge tag 'docs-5.9' of git://git.lwn.net/linux

2020-08-05T05:47:54+00:00

Pull documentation updates from Jonathan Corbet: "It's been a busy cycle for documentation - hopefully the busiest for a while to come. Changes include: - Some new Chinese translations - Progress on the battle against double words words and non-HTTPS URLs - Some block-mq documentation - More RST conversions from Mauro. At this point, that task is essentially complete, so we shouldn't see this kind of churn again for a while. Unless we decide to switch to asciidoc or something...:) - Lots of typo fixes, warning fixes, and more" * tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits) scripts/kernel-doc: optionally treat warnings as errors docs: ia64: correct typo mailmap: add entry for doc/zh_CN: add cpu-load Chinese version Documentation/admin-guide: tainted-kernels: fix spelling mistake MAINTAINERS: adjust kprobes.rst entry to new location devices.txt: document rfkill allocation PCI: correct flag name docs: filesystems: vfs: correct flag name docs: filesystems: vfs: correct sync_mode flag names docs: path-lookup: markup fixes for emphasis docs: path-lookup: more markup fixes docs: path-lookup: fix HTML entity mojibake CREDITS: Replace HTTP links with HTTPS ones docs: process: Add an example for creating a fixes tag doc/zh_CN: add Chinese translation prefer section doc/zh_CN: add clearing-warn-once Chinese version doc/zh_CN: add admin-guide index doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label futex: MAINTAINERS: Re-add selftests directory ...

dm crypt: Enable zoned block device support

2020-07-20T15:17:45+00:00

Enable support for zoned block devices. This is done by: 1) implementing the target report_zones method. 2) adding the DM_TARGET_ZONED_HM flag to the target features. 3) setting DM_CRYPT_NO_WRITE_WORKQUEUE flag to avoid IO processing via workqueue. 4) Introducing inline write encryption completion to preserve write ordering. The last point is implemented by introducing the internal flag DM_CRYPT_WRITE_INLINE. When set, kcryptd_crypt_write_convert() always waits inline for the completion of a write request encryption if the request is not already completed once crypt_convert() returns. Completion of write request encryption is signaled using the restart completion by kcryptd_async_done(). This mechanism allows using ciphers that have an asynchronous implementation, isolating dm-crypt from any potential request completion reordering for these ciphers. Signed-off-by: Damien Le Moal Signed-off-by: Mike Snitzer

dm crypt: add flags to optionally bypass kcryptd workqueues

2020-07-20T15:17:44+00:00

This is a follow up to [1] that detailed latency problems associated with dm-crypt's use of workqueues when processing IO. Current dm-crypt implementation creates a significant IO performance overhead (at least on small IO block sizes) for both latency and throughput. We suspect offloading IO request processing into workqueues and async threads is more harmful these days with the modern fast storage. I also did some digging into the dm-crypt git history and much of this async processing is not needed anymore, because the reasons it was added are mostly gone from the kernel. More details can be found in [2] (see "Git archeology" section). This change adds DM_CRYPT_NO_READ_WORKQUEUE and DM_CRYPT_NO_WRITE_WORKQUEUE flags for read and write BIOs, which direct dm-crypt to not offload crypto operations into kcryptd workqueues. In addition, writes are not buffered to be sorted in the dm-crypt red-black tree, but dispatched immediately. For cases, where crypto operations cannot happen (hard interrupt context, for example the read path of some NVME drivers), we offload the work to a tasklet rather than a workqueue. These flags only ensure no async BIO processing in the dm-crypt module. It is worth noting that some Crypto API implementations may offload encryption into their own workqueues, which are independent of the dm-crypt and its configuration. However upon enabling these new flags dm-crypt will instruct Crypto API not to backlog crypto requests. To give an idea of the performance gains for certain workloads, consider the script, and results when tested against various devices, detailed here: https://www.redhat.com/archives/dm-devel/2020-July/msg00138.html [1]: https://www.spinics.net/lists/dm-crypt/msg07516.html [2]: https://blog.cloudflare.com/speeding-up-linux-disk-encryption/ Signed-off-by: Ignat Korchagin Reviewed-by: Damien Le Moal Reviewed-by: Bob Liu Signed-off-by: Mike Snitzer

Replace HTTP links with HTTPS ones: LVM

2020-07-05T20:28:27+00:00

Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov Link: https://lore.kernel.org/r/20200627103138.71885-1-grandmaster@al2klimov.de Signed-off-by: Jonathan Corbet

block: rename generic_make_request to submit_bio_noacct

2020-07-01T13:27:24+00:00

generic_make_request has always been very confusingly misnamed, so rename it to submit_bio_noacct to make it clear that it is submit_bio minus accounting and a few checks. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

dm crypt: avoid truncating the logical block size

2020-06-05T18:59:59+00:00

queue_limits::logical_block_size got changed from unsigned short to unsigned int, but it was forgotten to update crypt_io_hints() to use the new type. Fix it. Fixes: ad6bf88a6c19 ("block: fix an integer overflow in logical block size") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Reviewed-by: Mikulas Patocka Signed-off-by: Mike Snitzer