PT-2026-40691 · Linux · Linux

Published 2026-05-13 · Updated 2026-05-13 · CVE-2026-43484

Mitre

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.

Related Identifiers

CVE-2026-43484

Affected Products

Linux

References · 8

• https://nvd.nist.gov/vuln/detail/CVE-2026-43484 · Security Note
• https://git.kernel.org/stable/c/0e06cc511c61cff1591e5435a207759adcc76b6d · Note
• https://git.kernel.org/stable/c/41dce4dae583a8ce06a7ebf4ce704c46a142957c · Note
• https://git.kernel.org/stable/c/45038e03f15e992c48603fff8c6b1c9be5397ac9 · Note
• https://git.kernel.org/stable/c/270277c2ab631044867adb1bd2f2433d3892de6e · Note
• https://git.kernel.org/stable/c/d3a3caf44c8ec26f5d63dc17c1c7242effa60ebc · Note
• https://git.kernel.org/stable/c/bb7fc2498c3bb25fa6a91f22f4760005325cfbd5 · Note
• https://git.kernel.org/stable/c/901084c51a0a8fb42a3f37d2e9c62083c495f824 · Note