Description
In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix uaf for bfqq in bfq_exit_icq_bfqq Commit 64dc8c732f5c ("block, bfq: fix possible uaf for 'bfqq->bic'") will access 'bic->bfqq' in bic_set_bfqq(), however, bfq_exit_icq_bfqq() can free bfqq first, and then call bic_set_bfqq(), which will cause uaf. Fix the problem by moving bfq_exit_bfqq() behind bic_set_bfqq().
Affected products
linux: linux kernel
References5
- git.kernel.org/stable/c/1425f1bb5df5239021fd09ebc2a5e8070e705d36 Patch
- git.kernel.org/stable/c/1ed959fef5b1c6f1a7a3fbea543698c30ebd6678 Patch
- git.kernel.org/stable/c/246cf66e300b76099b5dbd3fdd39e9a5dbc53f02 Patch
- git.kernel.org/stable/c/7949b0df3dd9f4817ed4a4e989fa9ee81df6205f Patch
- git.kernel.org/stable/c/cfe5b38c37720313eff0dec5517442c7ab3c9a20 Patch
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 6 · as of 8 November 2026
- CWE
- CWE-416
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