dm-pcache: fix use-after-free and invalid seg operations in kset_replay()
In kset_replay, when key->seg_gen is stale (key->seg_gen <
key->cache_pos.cache_seg->gen), cache_key_put(key) is called but then
key->cache_pos.cache_seg is accessed as the argument to cache_seg_get().
This is a use-after-free on the freed key memory. Although mempool
recycled memory is not immediately reclaimed or overwritten in practice,
this is still a potential UAF bug.
Additionally, for expired invalid keys, setting the cache->seg_map bit
and calling cache_seg_get() is unreasonable since the corresponding
segment data is no longer valid.
Fix both issues by moving cache_seg_get() and __set_bit() after the
gen check, so they only execute for valid keys, and using continue to
skip invalid keys.
Metrics
Affected Vendors & Products
No advisories yet.
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
Sun, 13 Sep 2026 06:45:00 +0000
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| Metrics |
cvssV3_1
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cvssV3_1
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Sat, 12 Sep 2026 00:15:00 +0000
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|---|---|---|
| Weaknesses | CWE-825 | |
| References |
| |
| Metrics |
threat_severity
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cvssV3_1
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Fri, 11 Sep 2026 23:45:00 +0000
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| Description | In the Linux kernel, the following vulnerability has been resolved: dm-pcache: fix use-after-free and invalid seg operations in kset_replay() In kset_replay, when key->seg_gen is stale (key->seg_gen < key->cache_pos.cache_seg->gen), cache_key_put(key) is called but then key->cache_pos.cache_seg is accessed as the argument to cache_seg_get(). This is a use-after-free on the freed key memory. Although mempool recycled memory is not immediately reclaimed or overwritten in practice, this is still a potential UAF bug. Additionally, for expired invalid keys, setting the cache->seg_map bit and calling cache_seg_get() is unreasonable since the corresponding segment data is no longer valid. Fix both issues by moving cache_seg_get() and __set_bit() after the gen check, so they only execute for valid keys, and using continue to skip invalid keys. | |
| Title | dm-pcache: fix use-after-free and invalid seg operations in kset_replay() | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-13T06:28:29.166Z
Reserved: 2026-08-26T14:34:25.804Z
Link: CVE-2026-80955
No data.
Status : Received
Published: 2026-09-11T20:19:01.287
Modified: 2026-09-13T07:17:02.700
Link: CVE-2026-80955
OpenCVE Enrichment
Updated: 2026-09-13T18:00:13Z