Description
In the Linux kernel, the following vulnerability has been resolved: mmc: core: Avoid bitfield RMW for claim/retune flags Move claimed and retune control flags out of the bitfield word to avoid unrelated RMW side effects in asynchronous contexts. The host->claimed bit shared a word with retune flags. Writes to claimed in __mmc_claim_host() or retune_now in mmc_mq_queue_rq() can overwrite other bits when concurrent updates happen in other contexts, triggering spurious WARN_ON(!host->claimed). Convert claimed, can_retune, retune_now and retune_paused to bool to remove shared-word coupling.
Affected products
linux: linux kernel
References7
- git.kernel.org/stable/c/0e06cc511c61cff1591e5435a207759adcc76b6d Patch
- git.kernel.org/stable/c/270277c2ab631044867adb1bd2f2433d3892de6e Patch
- git.kernel.org/stable/c/41dce4dae583a8ce06a7ebf4ce704c46a142957c Patch
- git.kernel.org/stable/c/45038e03f15e992c48603fff8c6b1c9be5397ac9 Patch
- git.kernel.org/stable/c/901084c51a0a8fb42a3f37d2e9c62083c495f824 Patch
- git.kernel.org/stable/c/bb7fc2498c3bb25fa6a91f22f4760005325cfbd5 Patch
- git.kernel.org/stable/c/d3a3caf44c8ec26f5d63dc17c1c7242effa60ebc Patch
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 2 · as of 14 November 2026
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