Description
In the Linux kernel, the following vulnerability has been resolved: dm era: fix out-of-bounds memory access for non-zero start sector dm-era tracks writes in target-relative blocks, but era_map() calculates the writeset block before applying the target offset. Tables with a non-zero start sector can therefore pass an absolute mapped-device block to metadata_current_marked(). If the absolute block is beyond the current writeset size, writeset_marked() tests past the end of the in-core bitset. KASAN reports this as a vmalloc-out-of-bounds access. Apply the target offset before calculating the era block so writeset lookups use the target-relative block number.
References8
- git.kernel.org/stable/c/1fcb5e29dd7a5b85adb9d8b539911741d878e829
- git.kernel.org/stable/c/7e1822f83c5a1ee7b4a19e98edde8770a10b4c71
- git.kernel.org/stable/c/9946a7176bd8c25ddd6e5f1799c54e572ee6bf0f
- git.kernel.org/stable/c/a868196f03c2b19418ae3d2b69e195d668a271e5
- git.kernel.org/stable/c/bafe3e720cdac38cd7ea4eb7852a8f2dbe1bbfe6
- git.kernel.org/stable/c/db5f9b4601f0012038e5a2628aedec2f47933380
- git.kernel.org/stable/c/e3ffa8e492e5cdee62d916ee3e9244ccce2b73c5
- git.kernel.org/stable/c/fe94a0b14010a3c267ff9a2508afb4f27ff1c5bf
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 52 · as of 11 November 2026
- CWE
- CWE-125
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