Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
dm-era: fix shadowed superblock leak on take-snap failure
metadata_take_snap() bumps the live superblock refcount and then dm_tm_shadow_block() allocates a new block for the metadata snapshot. If the subsequent dm_sm_inc_block() of writeset_tree_root or era_array_root fails, the function only unlocks the clone and returns. The newly allocated shadow block is never returned to the metadata space map, so each failed take-snap permanently leaks one metadata block.
Free the clone with dm_sm_dec_block() on those error paths, matching the final step of metadata_drop_snap().
Details
- Affected product:
- Debian 10 ELS , Debian 11 ELS , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 5.10.259 (+4 more)