CVE-2026-43484

Summary

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 Software

VendorProductVersion RangeStatus
LinuxLinux6c0cedd1ef9527ef13e66875746570e76a3188a7 < 41dce4dae583a8ce06a7ebf4ce704c46a142957caffected
LinuxLinux6c0cedd1ef9527ef13e66875746570e76a3188a7 < bb7fc2498c3bb25fa6a91f22f4760005325cfbd5affected
LinuxLinux6c0cedd1ef9527ef13e66875746570e76a3188a7 < 270277c2ab631044867adb1bd2f2433d3892de6eaffected
LinuxLinux6c0cedd1ef9527ef13e66875746570e76a3188a7 < 45038e03f15e992c48603fff8c6b1c9be5397ac9affected
LinuxLinux6c0cedd1ef9527ef13e66875746570e76a3188a7 < 0e06cc511c61cff1591e5435a207759adcc76b6daffected
LinuxLinux6c0cedd1ef9527ef13e66875746570e76a3188a7 < d3a3caf44c8ec26f5d63dc17c1c7242effa60ebcaffected
LinuxLinux6c0cedd1ef9527ef13e66875746570e76a3188a7 < 901084c51a0a8fb42a3f37d2e9c62083c495f824affected
LinuxLinux4.15affected
LinuxLinux0 < 4.15unaffected
LinuxLinux5.15.203 <= 5.15.*unaffected
LinuxLinux6.1.167 <= 6.1.*unaffected
LinuxLinux6.6.130 <= 6.6.*unaffected
LinuxLinux6.12.78 <= 6.12.*unaffected
LinuxLinux6.18.19 <= 6.18.*unaffected
LinuxLinux6.19.9 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References