CVE-2026-52905

Summary

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

mm/damon/core: disallow non-power of two min_region_sz on damon_start()

Commit d8f867fa0825 ("mm/damon: add damon_ctx->min_sz_region") introduced a bug that allows unaligned DAMON region address ranges. Commit c80f46ac228b ("mm/damon/core: disallow non-power of two min_region_sz") fixed it, but only for damon_commit_ctx() use case. Still, DAMON sysfs interface can emit non-power of two min_region_sz via damon_start(). Fix the path by adding the is_power_of_2() check on damon_start().

The issue was discovered by sashiko [1].

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxd8f867fa0825fb3e358457566d7326d8aab2406a < 1de2db19a6028abe7d905875922faef5b873de67affected
LinuxLinuxd8f867fa0825fb3e358457566d7326d8aab2406a < 89b6226b6c2a4add3939f361653a47c212d6ab75affected
LinuxLinuxd8f867fa0825fb3e358457566d7326d8aab2406a < 95093e5cb4c5b50a5b1a4b79f2942b62744bd66aaffected
LinuxLinux6.18affected
LinuxLinux0 < 6.18unaffected
LinuxLinux6.18.30 <= 6.18.*unaffected
LinuxLinux7.0.4 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References