CVE-2026-31484 (GCVE-0-2026-31484)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-08-05 12:22
VLAI
Title
io_uring/fdinfo: fix OOB read in SQE_MIXED wrap check
Summary
In the Linux kernel, the following vulnerability has been resolved: io_uring/fdinfo: fix OOB read in SQE_MIXED wrap check __io_uring_show_fdinfo() iterates over pending SQEs and, for 128-byte SQEs on an IORING_SETUP_SQE_MIXED ring, needs to detect when the second half of the SQE would be past the end of the sq_sqes array. The current check tests (++sq_head & sq_mask) == 0, but sq_head is only incremented when a 128-byte SQE is encountered, not on every iteration. The actual array index is sq_idx = (i + sq_head) & sq_mask, which can be sq_mask (the last slot) while the wrap check passes. Fix by checking sq_idx directly. Keep the sq_head increment so the loop still skips the second half of the 128-byte SQE on the next iteration.
Severity
7.1 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6639 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 1cba30bf9fdd6c982708f3587f609a30c370d889 , < ba21ab247a5be5382da7464b95afbe5f0e9aa503 (git)
Affected: 1cba30bf9fdd6c982708f3587f609a30c370d889 , < 5170efd9c344c68a8075dcb8ed38d3f8a60e7ed4 (git)
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Linux Linux Affected: 6.19
Unaffected: 0 , < 6.19 (semver)
Unaffected: 6.19.11 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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