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TI-2024-35635 Aliases CVE-2024-53166GHSA-6gmm-x3pr-vhmf

block, bfq: fix bfqq uaf in bfq_limit_depth()

Priority LOW 36CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix bfqq uaf in bfq_limit_depth() Set new allocated bfqq to bic or remove freed bfqq from bic are both protected by bfqd->lock, however bfq_limit_depth() is deferencing bfqq from bic without the lock, this can lead to UAF if the io_context is shared by multiple tasks. For example, test bfq with io_uring can trigger following UAF in v6.6: ================================================================== BUG: KASAN: slab-use-after-free in bfqq_group+0x15/0x50 Call Trace: <TASK> dump_stack_lvl+0x47/0x80 print_address_description.constprop.0+0x66/0x300 print_report+0x3e/0x70 kasan_report+0xb4/0xf0 bfqq_group+0x15/0x50 bfqq_request_over_limit+0x130/0x9a0 bfq_limit_depth+0x1b5/0x480 __blk_mq_alloc_requests+0x2b5/0xa00 blk_mq_get_new_requests+0x11d/0x1d0 blk_mq_submit_bio+0x286/0xb00 submit_bio_noacct_nocheck+0x331/0x400 __block_write_full_folio+0x3d0/0x640 writepage_cb+0x3b/0xc0 write_cache_pages+0x254/0x6c0 write_cache_pages+0x254/0x6c0 do_writepages+0x192/0x310 filemap_fdatawrite_wbc+0x95/0xc0 __filemap_fdatawrite_range+0x99/0xd0 filemap_write_and_wait_range.part.0+0x4d/0xa0 blkdev_read_iter+0xef/0x1e0 io_read+0x1b6/0x8a0 io_issue_sqe+0x87/0x300 io_wq_submit_work+0xeb/0x390 io_worker_handle_work+0x24d/0x550 io_wq_worker+0x27f/0x6c0 ret_from_fork_asm+0x1b/0x30 </TASK> Allocated by task 808602: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 __kasan_slab_alloc+0x83/0x90 kmem_cache_alloc_node+0x1b1/0x6d0 bfq_get_queue+0x138/0xfa0 bfq_get_bfqq_handle_split+0xe3/0x2c0 bfq_init_rq+0x196/0xbb0 bfq_insert_request.isra.0+0xb5/0x480 bfq_insert_requests+0x156/0x180 blk_mq_insert_request+0x15d/0x440 blk_mq_submit_bio+0x8a4/0xb00 submit_bio_noacct_nocheck+0x331/0x400 __blkdev_direct_IO_async+0x2dd/0x330 blkdev_write_iter+0x39a/0x450 io_write+0x22a/0x840 io_issue_sqe+0x87/0x300 io_wq_submit_work+0xeb/0x390 io_worker_handle_work+0x24d/0x550 io_wq_worker+0x27f/0x6c0 ret_from_fork+0x2d/0x50 ret_from_fork_asm+0x1b/0x30 Freed by task 808589: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_save_free_info+0x27/0x40 __kasan_slab_free+0x126/0x1b0 kmem_cache_free+0x10c/0x750 bfq_put_queue+0x2dd/0x770 __bfq_insert_request.isra.0+0x155/0x7a0 bfq_insert_request.isra.0+0x122/0x480 bfq_insert_requests+0x156/0x180 blk_mq_dispatch_plug_list+0x528/0x7e0 blk_mq_flush_plug_list.part.0+0xe5/0x590 __blk_flush_plug+0x3b/0x90 blk_finish_plug+0x40/0x60 do_writepages+0x19d/0x310 filemap_fdatawrite_wbc+0x95/0xc0 __filemap_fdatawrite_range+0x99/0xd0 filemap_write_and_wait_range.part.0+0x4d/0xa0 blkdev_read_iter+0xef/0x1e0 io_read+0x1b6/0x8a0 io_issue_sqe+0x87/0x300 io_wq_submit_work+0xeb/0x390 io_worker_handle_work+0x24d/0x550 io_wq_worker+0x27f/0x6c0 ret_from_fork+0x2d/0x50 ret_from_fork_asm+0x1b/0x30 Fix the problem by protecting bic_to_bfqq() with bfqd->lock.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00257 17th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.1.130, 6.6.64, 6.11.11 +2Red Hat: 1 advisory

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.17 and later6.1.130, 6.6.64, 6.11.11, 6.12.2, 6.13Patch availableCNA
  • Linux VendorLinux Affected 5.17 and later Fixed in 6.1.130, 6.6.64, 6.11.11, 6.12.2, 6.13 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*5.17 to before 6.6.64; 6.7 to before 6.11.11; 6.12 to before 6.12.2VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.17 to before 6.6.64; 6.7 to before 6.11.11; 6.12 to before 6.12.2 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.1.130, 6.6.64, 6.11.11, 6.12.2, 6.13

Red Hat 1 advisory

  • RHSA-2025:6966 Released 2025-05-13 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-570.12.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.12.1.el9_6, kernel-64k-devel-5.14.0-570.12.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-570.12.1.el9_6, kernel-64k-5.14.0-570.12.1.el9_6, kernel-64k-core-5.14.0-570.12.1.el9_6 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-570.12.1.el9_6, libperf-5.14.0-570.12.1.el9_6
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-570.12.1.el9_6, kernel-rt-64k-5.14.0-570.12.1.el9_6, kernel-rt-64k-core-5.14.0-570.12.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-570.12.1.el9_6, kernel-rt-core-5.14.0-570.12.1.el9_6, kernel-rt-debug-5.14.0-570.12.1.el9_6 +11

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2025:6966
Not affected: 3 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-53166
  2. 2026-10-03 Alias added: GHSA-6gmm-x3pr-vhmf
  3. 2026-10-29 Affected versions changed · Red Hat

References

Patch 4

Other 1

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences