The io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the PROVIDE_BUFFERS operation, which led to negative values being usedin mem_rw when reading /proc/<PID>/mem. This could be used to create a heap overflow leading to arbitrary code execution in the kernel. It was addressed via commit d1f82808877b ("io_uring: truncate lengths larger than MAX_RW_COUNT on provide buffers") (v5.13-rc1) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was introduced in ddf0322db79c ("io_uring: add IORING_OP_PROVIDE_BUFFERS") (v5.7-rc1).
History

No history.

cve-icon MITRE

Status: PUBLISHED

Assigner: canonical

Published: 2021-06-04T01:40:20.936072Z

Updated: 2024-09-16T22:09:25.883Z

Reserved: 2021-04-09T00:00:00

Link: CVE-2021-3491

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2021-06-04T02:15:07.253

Modified: 2024-11-21T06:21:40.063

Link: CVE-2021-3491

cve-icon Redhat

Severity : Important

Publid Date: 2021-05-11T00:00:00Z

Links: CVE-2021-3491 - Bugzilla