kernel/linux.git/drivers/md/dm-table.c, branch v5.10.257

dm: restrict dm device size to 2^63-512 bytes

2025-06-04T12:37:00+00:00

[ Upstream commit 45fc728515c14f53f6205789de5bfd72a95af3b8 ] The devices with size >= 2^63 bytes can't be used reliably by userspace because the type off_t is a signed 64-bit integer. Therefore, we limit the maximum size of a device mapper device to 2^63-512 bytes. Signed-off-by: Mikulas Patocka Signed-off-by: Sasha Levin

dm: fix copying after src array boundaries

2025-06-04T12:36:53+00:00

commit f1aff4bc199cb92c055668caed65505e3b4d2656 upstream. The blammed commit copied to argv the size of the reallocated argv, instead of the size of the old_argv, thus reading and copying from past the old_argv allocated memory. Following BUG_ON was hit: [ 3.038929][ T1] kernel BUG at lib/string_helpers.c:1040! [ 3.039147][ T1] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP ... [ 3.056489][ T1] Call trace: [ 3.056591][ T1] __fortify_panic+0x10/0x18 (P) [ 3.056773][ T1] dm_split_args+0x20c/0x210 [ 3.056942][ T1] dm_table_add_target+0x13c/0x360 [ 3.057132][ T1] table_load+0x110/0x3ac [ 3.057292][ T1] dm_ctl_ioctl+0x424/0x56c [ 3.057457][ T1] __arm64_sys_ioctl+0xa8/0xec [ 3.057634][ T1] invoke_syscall+0x58/0x10c [ 3.057804][ T1] el0_svc_common+0xa8/0xdc [ 3.057970][ T1] do_el0_svc+0x1c/0x28 [ 3.058123][ T1] el0_svc+0x50/0xac [ 3.058266][ T1] el0t_64_sync_handler+0x60/0xc4 [ 3.058452][ T1] el0t_64_sync+0x1b0/0x1b4 [ 3.058620][ T1] Code: f800865e a9bf7bfd 910003fd 941f48aa (d4210000) [ 3.058897][ T1] ---[ end trace 0000000000000000 ]--- [ 3.059083][ T1] Kernel panic - not syncing: Oops - BUG: Fatal exception Fix it by copying the size of src, and not the size of dst, as it was. Fixes: 5a2a6c428190 ("dm: always update the array size in realloc_argv on success") Cc: stable@vger.kernel.org Signed-off-by: Tudor Ambarus Signed-off-by: Mikulas Patocka Signed-off-by: Greg Kroah-Hartman

dm: always update the array size in realloc_argv on success

2025-06-04T12:36:51+00:00

commit 5a2a6c428190f945c5cbf5791f72dbea83e97f66 upstream. realloc_argv() was only updating the array size if it was called with old_argv already allocated. The first time it was called to create an argv array, it would allocate the array but return the array size as zero. dm_split_args() would think that it couldn't store any arguments in the array and would call realloc_argv() again, causing it to reallocate the initial slots (this time using GPF_KERNEL) and finally return a size. Aside from being wasteful, this could cause deadlocks on targets that need to process messages without starting new IO. Instead, realloc_argv should always update the allocated array size on success. Fixes: a0651926553c ("dm table: don't copy from a NULL pointer in realloc_argv()") Cc: stable@vger.kernel.org Signed-off-by: Benjamin Marzinski Signed-off-by: Mikulas Patocka Signed-off-by: Greg Kroah-Hartman

dm: limit the number of targets and parameter size area

2024-02-23T07:42:32+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: He Gao Signed-off-by: Greg Kroah-Hartman

dm table: Fix zoned model check and zone sectors check

2021-03-30T12:32:06+00:00

[ Upstream commit 2d669ceb69c276f7637cf760287ca4187add082e ] Commit 24f6b6036c9e ("dm table: fix zoned iterate_devices based device capability checks") triggered dm table load failure when dm-zoned device is set up for zoned block devices and a regular device for cache. The commit inverted logic of two callback functions for iterate_devices: device_is_zoned_model() and device_matches_zone_sectors(). The logic of device_is_zoned_model() was inverted then all destination devices of all targets in dm table are required to have the expected zoned model. This is fine for dm-linear, dm-flakey and dm-crypt on zoned block devices since each target has only one destination device. However, this results in failure for dm-zoned with regular cache device since that target has both regular block device and zoned block devices. As for device_matches_zone_sectors(), the commit inverted the logic to require all zoned block devices in each target have the specified zone_sectors. This check also fails for regular block device which does not have zones. To avoid the check failures, fix the zone model check and the zone sectors check. For zone model check, introduce the new feature flag DM_TARGET_MIXED_ZONED_MODEL, and set it to dm-zoned target. When the target has this flag, allow it to have destination devices with any zoned model. For zone sectors check, skip the check if the destination device is not a zoned block device. Also add comments and improve an error message to clarify expectations to the two checks. Fixes: 24f6b6036c9e ("dm table: fix zoned iterate_devices based device capability checks") Signed-off-by: Shin'ichiro Kawasaki Signed-off-by: Damien Le Moal Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin

dm table: fix zoned iterate_devices based device capability checks

2021-03-04T10:38:44+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 Signed-off-by: Greg Kroah-Hartman

dm table: fix DAX iterate_devices based device capability checks

2021-03-04T10:38:44+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

2021-03-04T10:38:44+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: avoid filesystem lookup in dm_get_dev_t()

2021-01-27T10:54:54+00:00

commit 809b1e4945774c9ec5619a8f4e2189b7b3833c0c upstream. This reverts commit 644bda6f3460 ("dm table: fall back to getting device using name_to_dev_t()") dm_get_dev_t() is just used to convert an arbitrary 'path' string into a dev_t. It doesn't presume that the device is present; that check will be done later, as the only caller is dm_get_device(), which does a dm_get_table_device() later on, which will properly open the device. So if the path string already _is_ in major:minor representation we can convert it directly, avoiding a recursion into the filesystem to lookup the block device. This avoids a hang in multipath_message() when the filesystem is inaccessible. Fixes: 644bda6f3460 ("dm table: fall back to getting device using name_to_dev_t()") Cc: stable@vger.kernel.org Signed-off-by: Hannes Reinecke Signed-off-by: Martin Wilck Reviewed-by: Christoph Hellwig Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman

dm: fix IO splitting

2020-12-04T19:53:15+00:00

Commit 882ec4e609c1 ("dm table: stack 'chunk_sectors' limit to account for target-specific splitting") caused a couple regressions: 1) Using lcm_not_zero() when stacking chunk_sectors was a bug because chunk_sectors must reflect the most limited of all devices in the IO stack. 2) DM targets that set max_io_len but that do _not_ provide an .iterate_devices method no longer had there IO split properly. And commit 5091cdec56fa ("dm: change max_io_len() to use blk_max_size_offset()") also caused a regression where DM no longer supported varied (per target) IO splitting. The implication being the potential for severely reduced performance for IO stacks that use a DM target like dm-cache to hide performance limitations of a slower device (e.g. one that requires 4K IO splitting). Coming full circle: Fix all these issues by discontinuing stacking chunk_sectors up using ti->max_io_len in dm_calculate_queue_limits(), add optional chunk_sectors override argument to blk_max_size_offset() and update DM's max_io_len() to pass ti->max_io_len to its blk_max_size_offset() call. Passing in an optional chunk_sectors override to blk_max_size_offset() allows for code reuse of block's centralized calculation for max IO size based on provided offset and split boundary. Fixes: 882ec4e609c1 ("dm table: stack 'chunk_sectors' limit to account for target-specific splitting") Fixes: 5091cdec56fa ("dm: change max_io_len() to use blk_max_size_offset()") Cc: stable@vger.kernel.org Reported-by: John Dorminy Reported-by: Bruce Johnston Reported-by: Kirill Tkhai Reviewed-by: John Dorminy Signed-off-by: Mike Snitzer Reviewed-by: Jens Axboe