CVE-2022-50488
- Source
- https://cve.org/CVERecord?id=CVE-2022-50488
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-50488.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2022-50488
- Downstream
CLSA (1)
DEBIAN (1)
RHSA (1)
SUSE (8)
UBUNTU (1)
- Related
- Published
- 2025-10-04T15:43:42Z
- Modified
- 2026-10-20T10:30:22Z
- Severity
-
- 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
- Summary
- block, bfq: fix possible uaf for 'bfqq->bic'
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
block, bfq: fix possible uaf for 'bfqq->bic'
Our test report a uaf for 'bfqq->bic' in 5.10:
================================================================== BUG: KASAN: use-after-free in bfq_select_queue+0x378/0xa30
CPU: 6 PID: 2318352 Comm: fsstress Kdump: loaded Not tainted 5.10.0-60.18.0.50.h602.kasan.eulerosv2r11.x86_64 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-20220320_160524-szxrtosci10000 04/01/2014 Call Trace: bfq_select_queue+0x378/0xa30 bfq_dispatch_request+0xe8/0x130 blk_mq_do_dispatch_sched+0x62/0xb0 __blk_mq_sched_dispatch_requests+0x215/0x2a0 blk_mq_sched_dispatch_requests+0x8f/0xd0 __blk_mq_run_hw_queue+0x98/0x180 __blk_mq_delay_run_hw_queue+0x22b/0x240 blk_mq_run_hw_queue+0xe3/0x190 blk_mq_sched_insert_requests+0x107/0x200 blk_mq_flush_plug_list+0x26e/0x3c0 blk_finish_plug+0x63/0x90 __iomap_dio_rw+0x7b5/0x910 iomap_dio_rw+0x36/0x80 ext4_dio_read_iter+0x146/0x190 [ext4] ext4_file_read_iter+0x1e2/0x230 [ext4] new_sync_read+0x29f/0x400 vfs_read+0x24e/0x2d0 ksys_read+0xd5/0x1b0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x61/0xc6
Commit 3bc5e683c67d ("bfq: Split shared queues on move between cgroups") changes that move process to a new cgroup will allocate a new bfqq to use, however, the old bfqq and new bfqq can point to the same bic:
- Initial state, two process with io in the same cgroup.
Process 1 Process 2 (BIC1) (BIC2) | Λ | Λ | | | | V | V | bfqq1 bfqq2
- bfqq1 is merged to bfqq2.
Process 1 Process 2 (BIC1) (BIC2) | | -------------| V bfqq1 bfqq2(coop)
- Process 1 exit, then issue new io(denoce IOA) from Process 2.
(BIC2) | Λ | | V | bfqq2(coop)
- Before IOA is completed, move Process 2 to another cgroup and issue io.
Process 2 (BIC2) Λ |--------------
| V bfqq2 bfqq3Now that BIC2 points to bfqq3, while bfqq2 and bfqq3 both point to BIC2. If all the requests are completed, and Process 2 exit, BIC2 will be freed while there is no guarantee that bfqq2 will be freed before BIC2.
Fix the problem by clearing bfqq->bic while bfqq is detached from bic.
- Database specific
{ "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50488.json" }- References
-
- https://git.kernel.org/stable/c/094f3d9314d67691cb21ba091c1b528f6e3c4893
- https://git.kernel.org/stable/c/5533742c7cb1bc9b1f0bf401cc397d44a3a9e07a
- https://git.kernel.org/stable/c/64dc8c732f5c2b406cc752e6aaa1bd5471159cab
- https://git.kernel.org/stable/c/761564d93c8265f65543acf0a576b32d66bfa26a
- https://git.kernel.org/stable/c/b22fd72bfebda3956efc4431b60ddfc0a51e03e0
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50488.json
- https://nvd.nist.gov/vuln/detail/CVE-2022-50488
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced4dfc12f8c94c8052e975060f595938f75e8b7165Fixed5533742c7cb1bc9b1f0bf401cc397d44a3a9e07a
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced81b7d0c717a487ec50e2924a773ff501ee40f0d5Fixed094f3d9314d67691cb21ba091c1b528f6e3c4893
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced3bc5e683c67d94bd839a1da2e796c15847b51b69Fixedb22fd72bfebda3956efc4431b60ddfc0a51e03e0Fixed761564d93c8265f65543acf0a576b32d66bfa26aFixed64dc8c732f5c2b406cc752e6aaa1bd5471159cab
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced5.10.121Fixed5.10.175
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced5.15.46Fixed5.15.86
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced5.4.198Fixed5.5
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced5.17.14Fixed5.18
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced5.18.3Fixed5.19
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced31326bf551269fb9bafa84ca99172b8340e5d8f8
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced43c51b86dbe551cff5d39b88aa2f41d29479f9c4
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced8615f6c0c9e7cf0ca90b6b5408784d797cbe5621
Affected versions
v5.*
Linux / Kernel
Package
- Name
- Kernel