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authorYe Bin <yebin10@huawei.com>2020-09-01 14:25:44 +0800
committerMike Snitzer <snitzer@redhat.com>2020-09-02 13:38:40 -0400
commit3a653b205f29b3f9827a01a0c88bfbcb0d169494 (patch)
treef107efa83cce9414e535847930e5c7e68d989d0e /drivers/md
parent219403d7e56f9b716ad80ab87db85d29547ee73e (diff)
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.c2
-rw-r--r--drivers/md/persistent-data/dm-block-manager.c14
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);