CVE-2022-49377

Description

In the Linux kernel, the following vulnerability has been resolved: blk-mq: don't touch ->tagset in blk_mq_get_sq_hctx blk_mq_run_hw_queues() could be run when there isn't queued request and after queue is cleaned up, at that time tagset is freed, because tagset lifetime is covered by driver, and often freed after blk_cleanup_queue() returns. So don't touch ->tagset for figuring out current default hctx by the mapping built in request queue, so use-after-free on tagset can be avoided. Meantime this way should be fast than retrieving mapping from tagset.

CVSS Metrics

• v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Trends

Current EPSS score: 0.07%• Percentile: 22%

Techniques & Countermeasures

• CWE-416•Use After Free

  The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Affected Systems

• linux•linux

  ≥ b6e68ee82585f2ee890b0a897a6aacbf49a467bb, < 460aa288c5cd0544dcf933a2f0ad0e8c6d2d35ff | ≥ b6e68ee82585f2ee890b0a897a6aacbf49a467bb, < b140bac470b4f707cda59c7266214246238661df | ≥ b6e68ee82585f2ee890b0a897a6aacbf49a467bb, < 70fdd922c7bf8949f8df109cf2635dff64c90392 | ≥ b6e68ee82585f2ee890b0a897a6aacbf49a467bb, < 5d05426e2d5fd7df8afc866b78c36b37b00188b7 | 5.12

• linux•linux_kernel

  ≥ 5.12, < 5.15.47 | ≥ 5.16, < 5.17.15 | ≥ 5.18, < 5.18.4

References (4)

• https://git.kernel.org/stable/c/460aa288c5cd0544dcf933a2f0ad0e8c6d2d35ff
• https://git.kernel.org/stable/c/b140bac470b4f707cda59c7266214246238661df
• https://git.kernel.org/stable/c/70fdd922c7bf8949f8df109cf2635dff64c90392
• https://git.kernel.org/stable/c/5d05426e2d5fd7df8afc866b78c36b37b00188b7