kernel/linux.git/drivers/md/dm-table.c, branch v6.6.39

dm: limit the number of targets and parameter size area

2024-02-23T08:25:27+00:00

commit bd504bcfec41a503b32054da5472904b404341a4 upstream. The kvmalloc function fails with a warning if the size is larger than INT_MAX. The warning was triggered by a syscall testing robot. In order to avoid the warning, this commit limits the number of targets to 1048576 and the size of the parameter area to 1073741824. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm: fix a race condition in retrieve_deps

2023-09-14T15:18:29+00:00

There's a race condition in the multipath target when retrieve_deps races with multipath_message calling dm_get_device and dm_put_device. retrieve_deps walks the list of open devices without holding any lock but multipath may add or remove devices to the list while it is running. The end result may be memory corruption or use-after-free memory access. See this description of a UAF with multipath_message(): https://listman.redhat.com/archives/dm-devel/2022-October/052373.html Fix this bug by introducing a new rw semaphore "devices_lock". We grab devices_lock for read in retrieve_deps and we grab it for write in dm_get_device and dm_put_device. Reported-by: Luo Meng Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Tested-by: Li Lingfeng Signed-off-by: Mike Snitzer

block: replace fmode_t with a block-specific type for block open flags

2023-06-12T14:04:05+00:00

The only overlap between the block open flags mapped into the fmode_t and other uses of fmode_t are FMODE_READ and FMODE_WRITE. Define a new blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and ->ioctl and stop abusing fmode_t. Signed-off-by: Christoph Hellwig Acked-by: Jack Wang [rnbd] Reviewed-by: Hannes Reinecke Reviewed-by: Christian Brauner Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de Signed-off-by: Jens Axboe

dm: only call early_lookup_bdev from early boot context

2023-06-05T16:57:40+00:00

early_lookup_bdev is supposed to only be called from the early boot code, but dm_get_device calls it as a general fallback when lookup_bdev fails, which is problematic because early_lookup_bdev bypasses all normal path based permission checking, and might cause problems with certain container environments renaming devices. Switch to only call early_lookup_bdev when dm is built-in and the system state in not running yet. This means it is still available when tables are constructed by dm-init.c from the kernel command line, but not otherwise. Note that this strictly speaking changes the kernel ABI as the PARTUUID= and PARTLABEL= style syntax is now not available during a running systems. They never were intended for that, but this breaks things we'll have to figure out a way to make them available again. But if avoidable in any way I'd rather avoid that. Signed-off-by: Christoph Hellwig Reviewed-by: Mike Snitzer Link: https://lore.kernel.org/r/20230531125535.676098-21-hch@lst.de Signed-off-by: Jens Axboe

dm: remove dm_get_dev_t

2023-06-05T16:57:40+00:00

Open code dm_get_dev_t in the only remaining caller, and propagate the exact error code from lookup_bdev and early_lookup_bdev. Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20230531125535.676098-20-hch@lst.de Signed-off-by: Jens Axboe

init: improve the name_to_dev_t interface

2023-06-05T16:56:46+00:00

name_to_dev_t has a very misleading name, that doesn't make clear it should only be used by the early init code, and also has a bad calling convention that doesn't allow returning different kinds of errors. Rename it to early_lookup_bdev to make the use case clear, and return an errno, where -EINVAL means the string could not be parsed, and -ENODEV means it the string was valid, but there was no device found for it. Also stub out the whole call for !CONFIG_BLOCK as all the non-block root cases are always covered in the caller. Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20230531125535.676098-14-hch@lst.de Signed-off-by: Jens Axboe

Merge tag 'for-6.4/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2023-04-26T20:05:21+00:00

Pull device mapper updates from Mike Snitzer: - Split dm-bufio's rw_semaphore and rbtree. Offers improvements to dm-bufio's locking to allow increased concurrent IO -- particularly for read access for buffers already in dm-bufio's cache. - Also split dm-bio-prison-v1's spinlock and rbtree with comparable aim at improving concurrent IO (for the DM thinp target). - Both the dm-bufio and dm-bio-prison-v1 scaling of the number of locks and rbtrees used are managed by dm_num_hash_locks(). And the hash function used by both is dm_hash_locks_index(). - Allow DM targets to require DISCARD, WRITE_ZEROES and SECURE_ERASE to be split at the target specified boundary (in terms of max_discard_sectors, max_write_zeroes_sectors and max_secure_erase_sectors respectively). - DM verity error handling fix for check_at_most_once on FEC. - Update DM verity target to emit audit events on verification failure and more. - DM core ->io_hints improvements needed in support of new discard support that is added to the DM "zero" and "error" targets. - Fix missing kmem_cache_destroy() call in initialization error path of both the DM integrity and DM clone targets. - A couple fixes for DM flakey, also add "error_reads" feature. - Fix DM core's resume to not lock FS when the DM map is NULL; otherwise initial table load can race with FS mount that takes superblock's ->s_umount rw_semaphore. - Various small improvements to both DM core and DM targets. * tag 'for-6.4/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (40 commits) dm: don't lock fs when the map is NULL in process of resume dm flakey: add an "error_reads" option dm flakey: remove trailing space in the table line dm flakey: fix a crash with invalid table line dm ioctl: fix nested locking in table_clear() to remove deadlock concern dm: unexport dm_get_queue_limits() dm: allow targets to require splitting WRITE_ZEROES and SECURE_ERASE dm: add helper macro for simple DM target module init and exit dm raid: remove unused d variable dm: remove unnecessary (void*) conversions dm mirror: add DMERR message if alloc_workqueue fails dm: push error reporting down to dm_register_target() dm integrity: call kmem_cache_destroy() in dm_integrity_init() error path dm clone: call kmem_cache_destroy() in dm_clone_init() error path dm error: add discard support dm zero: add discard support dm table: allow targets without devices to set ->io_hints dm verity: emit audit events on verification failure and more dm verity: fix error handling for check_at_most_once on FEC dm: improve hash_locks sizing and hash function ...

dm table: allow targets without devices to set ->io_hints

2023-04-04T17:30:17+00:00

In dm_calculate_queue_limits, add call to ->io_hints hook if the target doesn't provide ->iterate_devices. This is needed so the "error" and "zero" targets may support discards. The 2 following commits will add their respective discard support. Signed-off-by: Mikulas Patocka Tested-by: Milan Broz Signed-off-by: Mike Snitzer

blk-crypto: make blk_crypto_evict_key() return void

2023-03-16T15:35:09+00:00

blk_crypto_evict_key() is only called in contexts such as inode eviction where failure is not an option. So there is nothing the caller can do with errors except log them. (dm-table.c does "use" the error code, but only to pass on to upper layers, so it doesn't really count.) Just make blk_crypto_evict_key() return void and log errors itself. Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20230315183907.53675-2-ebiggers@kernel.org Signed-off-by: Jens Axboe

dm: avoid split of quoted strings where possible

2023-02-14T19:23:07+00:00

Signed-off-by: Heinz Mauelshagen Signed-off-by: Mike Snitzer