CVE-2026-53334

Summary

In the Linux kernel, the following vulnerability has been resolved:

mm/damon/reclaim: handle ctx allocation failure

Patch series "mm/damon/{reclaim,lru_sort}: handle ctx allocation failures".

DAMON_RECLAIM and DAMON_LRU_SORT could dereference NULL pointers if their damon_ctx object allocations fail. The bugs are expected to happen infrequently because the allocations are arguably too small to fail on common setups. But theoretically they are possible and the consequences are bad. Fix those.

The issues were discovered [1] by Sashiko.

This patch (of 2):

DAMON_RECLAIM allocates the damon_ctx object for its kdamond in its init function. damon_reclaim_enabled_store() wrongly assumes the allocation will always succeed once tried. If the damon_ctx allocation was failed, therefore, code execution reaches to damon_commit_ctx() while 'ctx' is NULL. As a result, it dereferences the NULL 'ctx' pointer. Avoid the NULL dereference by returning -ENOMEM if 'ctx' is NULL.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux3f7a914ab9a5e46cf8aac7de270f02aa3f63de04 < 66bc00ea37fa8ec14be5a3909d067a5967ef234baffected
LinuxLinux3f7a914ab9a5e46cf8aac7de270f02aa3f63de04 < 635b45ce61de53a9357e28ac97461428cdb650f0affected
LinuxLinux3f7a914ab9a5e46cf8aac7de270f02aa3f63de04 < 7e2ed8a29427af534bf2cb9b8bc51762b8b6e654affected
LinuxLinux6.18affected
LinuxLinux0 < 6.18unaffected
LinuxLinux6.18.36 <= 6.18.*unaffected
LinuxLinux7.0.13 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References