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| author |   Ye Bin <yebin10@huawei.com> | 2020-09-01 14:25:44 +0800 |
|---|---|---|
| committer |   Mike Snitzer <snitzer@redhat.com> | 2020-09-02 13:38:40 -0400 |
| commit | 3a653b205f29b3f9827a01a0c88bfbcb0d169494 (patch) | |
| tree | f107efa83cce9414e535847930e5c7e68d989d0e /drivers/md | |
| parent | dm thin metadata: Avoid returning cmd->bm wild pointer on error (diff) | |
| download | wireguard-linux-3a653b205f29b3f9827a01a0c88bfbcb0d169494.tar.xz wireguard-linux-3a653b205f29b3f9827a01a0c88bfbcb0d169494.zip | |
dm thin metadata: Fix use-after-free in dm_bm_set_read_only
The following error ocurred when testing disk online/offline:
[ 301.798344] device-mapper: thin: 253:5: aborting current metadata transaction
[ 301.848441] device-mapper: thin: 253:5: failed to abort metadata transaction
[ 301.849206] Aborting journal on device dm-26-8.
[ 301.850489] EXT4-fs error (device dm-26) in __ext4_new_inode:943: Journal has aborted
[ 301.851095] EXT4-fs (dm-26): Delayed block allocation failed for inode 398742 at logical offset 181 with max blocks 19 with error 30
[ 301.854476] BUG: KASAN: use-after-free in dm_bm_set_read_only+0x3a/0x40 [dm_persistent_data]
Reason is:
metadata_operation_failed
abort_transaction
dm_pool_abort_metadata
__create_persistent_data_objects
r = __open_or_format_metadata
if (r) --> If failed will free pmd->bm but pmd->bm not set NULL
dm_block_manager_destroy(pmd->bm);
set_pool_mode
dm_pool_metadata_read_only(pool->pmd);
dm_bm_set_read_only(pmd->bm); --> use-after-free
Add checks to see if pmd->bm is NULL in dm_bm_set_read_only and
dm_bm_set_read_write functions. If bm is NULL it means creating the
bm failed and so dm_bm_is_read_only must return true.
Signed-off-by: Ye Bin <yebin10@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-thin-metadata.c | 2 | ||||
| -rw-r--r-- | drivers/md/persistent-data/dm-block-manager.c | 14 |
2 files changed, 9 insertions, 7 deletions
diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c index ddb7f1f0bc48..b461836b6d26 100644 --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -958,7 +958,7 @@ int dm_pool_metadata_close(struct dm_pool_metadata *pmd) } pmd_write_lock_in_core(pmd); - if (!dm_bm_is_read_only(pmd->bm) && !pmd->fail_io) { + if (!pmd->fail_io && !dm_bm_is_read_only(pmd->bm)) { r = __commit_transaction(pmd); if (r < 0) DMWARN("%s: __commit_transaction() failed, error = %d", diff --git a/drivers/md/persistent-data/dm-block-manager.c b/drivers/md/persistent-data/dm-block-manager.c index 749ec268d957..54c089a50b15 100644 --- a/drivers/md/persistent-data/dm-block-manager.c +++ b/drivers/md/persistent-data/dm-block-manager.c @@ -493,7 +493,7 @@ int dm_bm_write_lock(struct dm_block_manager *bm, void *p; int r; - if (bm->read_only) + if (dm_bm_is_read_only(bm)) return -EPERM; p = dm_bufio_read(bm->bufio, b, (struct dm_buffer **) result); @@ -562,7 +562,7 @@ int dm_bm_write_lock_zero(struct dm_block_manager *bm, struct buffer_aux *aux; void *p; - if (bm->read_only) + if (dm_bm_is_read_only(bm)) return -EPERM; p = dm_bufio_new(bm->bufio, b, (struct dm_buffer **) result); @@ -602,7 +602,7 @@ EXPORT_SYMBOL_GPL(dm_bm_unlock); int dm_bm_flush(struct dm_block_manager *bm) { - if (bm->read_only) + if (dm_bm_is_read_only(bm)) return -EPERM; return dm_bufio_write_dirty_buffers(bm->bufio); @@ -616,19 +616,21 @@ void dm_bm_prefetch(struct dm_block_manager *bm, dm_block_t b) bool dm_bm_is_read_only(struct dm_block_manager *bm) { - return bm->read_only; + return (bm ? bm->read_only : true); } EXPORT_SYMBOL_GPL(dm_bm_is_read_only); void dm_bm_set_read_only(struct dm_block_manager *bm) { - bm->read_only = true; + if (bm) + bm->read_only = true; } EXPORT_SYMBOL_GPL(dm_bm_set_read_only); void dm_bm_set_read_write(struct dm_block_manager *bm) { - bm->read_only = false; + if (bm) + bm->read_only = false; } EXPORT_SYMBOL_GPL(dm_bm_set_read_write); |