kernel/linux.git/drivers/md, branch v5.4.113

dm ioctl: fix out of bounds array access when no devices

2021-03-30T12:35:24+00:00

commit 4edbe1d7bcffcd6269f3b5eb63f710393ff2ec7a upstream. If there are not any dm devices, we need to zero the "dev" argument in the first structure dm_name_list. However, this can cause out of bounds write, because the "needed" variable is zero and len may be less than eight. Fix this bug by reporting DM_BUFFER_FULL_FLAG if the result buffer is too small to hold the "nl->dev" value. Signed-off-by: Mikulas Patocka Reported-by: Dan Carpenter Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm verity: fix DM_VERITY_OPTS_MAX value

2021-03-30T12:35:24+00:00

commit 160f99db943224e55906dd83880da1a704c6e6b9 upstream. Three optional parameters must be accepted at once in a DM verity table, e.g.: (verity_error_handling_mode) (ignore_zero_block) (check_at_most_once) Fix this to be possible by incrementing DM_VERITY_OPTS_MAX. Signed-off-by: JeongHyeon Lee Fixes: 843f38d382b1 ("dm verity: add 'check_at_most_once' option to only validate hashes once") Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm table: fix zoned iterate_devices based device capability checks

2021-03-11T13:06:49+00:00

commit 24f6b6036c9eec21191646930ad42808e6180510 upstream. Fix dm_table_supports_zoned_model() and invert logic of both iterate_devices_callout_fn so that all devices' zoned capabilities are properly checked. Add one more parameter to dm_table_any_dev_attr(), which is actually used as the @data parameter of iterate_devices_callout_fn, so that dm_table_matches_zone_sectors() can be replaced by dm_table_any_dev_attr(). Fixes: dd88d313bef02 ("dm table: add zoned block devices validation") Cc: stable@vger.kernel.org Signed-off-by: Jeffle Xu Signed-off-by: Mike Snitzer [jeffle: also convert partial completion check] Signed-off-by: Greg Kroah-Hartman

dm table: fix DAX iterate_devices based device capability checks

2021-03-11T13:06:49+00:00

commit 5b0fab508992c2e120971da658ce80027acbc405 upstream. Fix dm_table_supports_dax() and invert logic of both iterate_devices_callout_fn so that all devices' DAX capabilities are properly checked. Fixes: 545ed20e6df6 ("dm: add infrastructure for DAX support") Cc: stable@vger.kernel.org Signed-off-by: Jeffle Xu Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm table: fix iterate_devices based device capability checks

2021-03-11T13:06:49+00:00

commit a4c8dd9c2d0987cf542a2a0c42684c9c6d78a04e upstream. According to the definition of dm_iterate_devices_fn: * This function must iterate through each section of device used by the * target until it encounters a non-zero return code, which it then returns. * Returns zero if no callout returned non-zero. For some target type (e.g. dm-stripe), one call of iterate_devices() may iterate multiple underlying devices internally, in which case a non-zero return code returned by iterate_devices_callout_fn will stop the iteration in advance. No iterate_devices_callout_fn should return non-zero unless device iteration should stop. Rename dm_table_requires_stable_pages() to dm_table_any_dev_attr() and elevate it for reuse to stop iterating (and return non-zero) on the first device that causes iterate_devices_callout_fn to return non-zero. Use dm_table_any_dev_attr() to properly iterate through devices. Rename device_is_nonrot() to device_is_rotational() and invert logic accordingly to fix improper disposition. Fixes: c3c4555edd10 ("dm table: clear add_random unless all devices have it set") Fixes: 4693c9668fdc ("dm table: propagate non rotational flag") Cc: stable@vger.kernel.org Signed-off-by: Jeffle Xu Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm verity: fix FEC for RS roots unaligned to block size

2021-03-09T10:09:37+00:00

commit df7b59ba9245c4a3115ebaa905e3e5719a3810da upstream. Optional Forward Error Correction (FEC) code in dm-verity uses Reed-Solomon code and should support roots from 2 to 24. The error correction parity bytes (of roots lengths per RS block) are stored on a separate device in sequence without any padding. Currently, to access FEC device, the dm-verity-fec code uses dm-bufio client with block size set to verity data block (usually 4096 or 512 bytes). Because this block size is not divisible by some (most!) of the roots supported lengths, data repair cannot work for partially stored parity bytes. This fix changes FEC device dm-bufio block size to "roots << SECTOR_SHIFT" where we can be sure that the full parity data is always available. (There cannot be partial FEC blocks because parity must cover whole sectors.) Because the optional FEC starting offset could be unaligned to this new block size, we have to use dm_bufio_set_sector_offset() to configure it. The problem is easily reproduced using veritysetup, e.g. for roots=13: # create verity device with RS FEC dd if=/dev/urandom of=data.img bs=4096 count=8 status=none veritysetup format data.img hash.img --fec-device=fec.img --fec-roots=13 | awk '/^Root hash/{ print $3 }' >roothash # create an erasure that should be always repairable with this roots setting dd if=/dev/zero of=data.img conv=notrunc bs=1 count=8 seek=4088 status=none # try to read it through dm-verity veritysetup open data.img test hash.img --fec-device=fec.img --fec-roots=13 $(cat roothash) dd if=/dev/mapper/test of=/dev/null bs=4096 status=noxfer # wait for possible recursive recovery in kernel udevadm settle veritysetup close test With this fix, errors are properly repaired. device-mapper: verity-fec: 7:1: FEC 0: corrected 8 errors ... Without it, FEC code usually ends on unrecoverable failure in RS decoder: device-mapper: verity-fec: 7:1: FEC 0: failed to correct: -74 ... This problem is present in all kernels since the FEC code's introduction (kernel 4.5). It is thought that this problem is not visible in Android ecosystem because it always uses a default RS roots=2. Depends-on: a14e5ec66a7a ("dm bufio: subtract the number of initial sectors in dm_bufio_get_device_size") Signed-off-by: Milan Broz Tested-by: Jérôme Carretero Reviewed-by: Sami Tolvanen Cc: stable@vger.kernel.org # 4.5+ Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm bufio: subtract the number of initial sectors in dm_bufio_get_device_size

2021-03-09T10:09:37+00:00

commit a14e5ec66a7a66e57b24e2469f9212a78460207e upstream. dm_bufio_get_device_size returns the device size in blocks. Before returning the value, we must subtract the nubmer of starting sectors. The number of starting sectors may not be divisible by block size. Note that currently, no target is using dm_bufio_set_sector_offset and dm_bufio_get_device_size simultaneously, so this change has no effect. However, an upcoming dm-verity-fec fix needs this change. Signed-off-by: Mikulas Patocka Reviewed-by: Milan Broz Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm era: Update in-core bitset after committing the metadata

2021-03-04T09:26:53+00:00

commit 2099b145d77c1d53f5711f029c37cc537897cee6 upstream. In case of a system crash, dm-era might fail to mark blocks as written in its metadata, although the corresponding writes to these blocks were passed down to the origin device and completed successfully. Consider the following sequence of events: 1. We write to a block that has not been yet written in the current era 2. era_map() checks the in-core bitmap for the current era and sees that the block is not marked as written. 3. The write is deferred for submission after the metadata have been updated and committed. 4. The worker thread processes the deferred write (process_deferred_bios()) and marks the block as written in the in-core bitmap, **before** committing the metadata. 5. The worker thread starts committing the metadata. 6. We do more writes that map to the same block as the write of step (1) 7. era_map() checks the in-core bitmap and sees that the block is marked as written, **although the metadata have not been committed yet**. 8. These writes are passed down to the origin device immediately and the device reports them as completed. 9. The system crashes, e.g., power failure, before the commit from step (5) finishes. When the system recovers and we query the dm-era target for the list of written blocks it doesn't report the aforementioned block as written, although the writes of step (6) completed successfully. The issue is that era_map() decides whether to defer or not a write based on non committed information. The root cause of the bug is that we update the in-core bitmap, **before** committing the metadata. Fix this by updating the in-core bitmap **after** successfully committing the metadata. Fixes: eec40579d84873 ("dm: add era target") Cc: stable@vger.kernel.org # v3.15+ Signed-off-by: Nikos Tsironis Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm era: only resize metadata in preresume

2021-03-04T09:26:52+00:00

commit cca2c6aebe86f68103a8615074b3578e854b5016 upstream. Metadata resize shouldn't happen in the ctr. The ctr loads a temporary (inactive) table that will only become active upon resume. That is why resize should always be done in terms of resume. Otherwise a load (ctr) whose inactive table never becomes active will incorrectly resize the metadata. Also, perform the resize directly in preresume, instead of using the worker to do it. The worker might run other metadata operations, e.g., it could start digestion, before resizing the metadata. These operations will end up using the old size. This could lead to errors, like: device-mapper: era: metadata_digest_transcribe_writeset: dm_array_set_value failed device-mapper: era: process_old_eras: digest step failed, stopping digestion The reason of the above error is that the worker started the digestion of the archived writeset using the old, larger size. As a result, metadata_digest_transcribe_writeset tried to write beyond the end of the era array. Fixes: eec40579d84873 ("dm: add era target") Cc: stable@vger.kernel.org # v3.15+ Signed-off-by: Nikos Tsironis Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm era: Reinitialize bitset cache before digesting a new writeset

2021-03-04T09:26:52+00:00

commit 2524933307fd0036d5c32357c693c021ab09a0b0 upstream. In case of devices with at most 64 blocks, the digestion of consecutive eras uses the writeset of the first era as the writeset of all eras to digest, leading to lost writes. That is, we lose the information about what blocks were written during the affected eras. The digestion code uses a dm_disk_bitset object to access the archived writesets. This structure includes a one word (64-bit) cache to reduce the number of array lookups. This structure is initialized only once, in metadata_digest_start(), when we kick off digestion. But, when we insert a new writeset into the writeset tree, before the digestion of the previous writeset is done, or equivalently when there are multiple writesets in the writeset tree to digest, then all these writesets are digested using the same cache and the cache is not re-initialized when moving from one writeset to the next. For devices with more than 64 blocks, i.e., the size of the cache, the cache is indirectly invalidated when we move to a next set of blocks, so we avoid the bug. But for devices with at most 64 blocks we end up using the same cached data for digesting all archived writesets, i.e., the cache is loaded when digesting the first writeset and it never gets reloaded, until the digestion is done. As a result, the writeset of the first era to digest is used as the writeset of all the following archived eras, leading to lost writes. Fix this by reinitializing the dm_disk_bitset structure, and thus invalidating the cache, every time the digestion code starts digesting a new writeset. Fixes: eec40579d84873 ("dm: add era target") Cc: stable@vger.kernel.org # v3.15+ Signed-off-by: Nikos Tsironis Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman