CVE-2022-48869

Advisory lineage Upstream: 0 Downstream: 7
Analyzed
Published: 21 Aug 2024, 06:09
Last modified:11 May 2026, 18:48

Vulnerability Summary

Overall Risk (default)
low
19/100
CVSS Score
4.7 MEDIUM
v3.1 (nvd)
EPSS Score
0.02% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

21 Aug 2024, 06:09
Published
Vulnerability first disclosed
11 May 2026, 18:48
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: USB: gadgetfs: Fix race between mounting and unmounting The syzbot fuzzer and Gerald Lee have identified a use-after-free bug in the gadgetfs driver, involving processes concurrently mounting and unmounting the gadgetfs filesystem. In particular, gadgetfs_fill_super() can race with gadgetfs_kill_sb(), causing the latter to deallocate the_device while the former is using it. The output from KASAN says, in part: BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:102 [inline] BUG: KASAN: use-after-free in atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:176 [inline] BUG: KASAN: use-after-free in __refcount_sub_and_test include/linux/refcount.h:272 [inline] BUG: KASAN: use-after-free in __refcount_dec_and_test include/linux/refcount.h:315 [inline] BUG: KASAN: use-after-free in refcount_dec_and_test include/linux/refcount.h:333 [inline] BUG: KASAN: use-after-free in put_dev drivers/usb/gadget/legacy/inode.c:159 [inline] BUG: KASAN: use-after-free in gadgetfs_kill_sb+0x33/0x100 drivers/usb/gadget/legacy/inode.c:2086 Write of size 4 at addr ffff8880276d7840 by task syz-executor126/18689 CPU: 0 PID: 18689 Comm: syz-executor126 Not tainted 6.1.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: <TASK> ... atomic_fetch_sub_release include/linux/atomic/atomic-instrumented.h:176 [inline] __refcount_sub_and_test include/linux/refcount.h:272 [inline] __refcount_dec_and_test include/linux/refcount.h:315 [inline] refcount_dec_and_test include/linux/refcount.h:333 [inline] put_dev drivers/usb/gadget/legacy/inode.c:159 [inline] gadgetfs_kill_sb+0x33/0x100 drivers/usb/gadget/legacy/inode.c:2086 deactivate_locked_super+0xa7/0xf0 fs/super.c:332 vfs_get_super fs/super.c:1190 [inline] get_tree_single+0xd0/0x160 fs/super.c:1207 vfs_get_tree+0x88/0x270 fs/super.c:1531 vfs_fsconfig_locked fs/fsopen.c:232 [inline] The simplest solution is to ensure that gadgetfs_fill_super() and gadgetfs_kill_sb() are serialized by making them both acquire a new mutex.

CVSS Metrics

  • v3.1•MEDIUM•Score: 4.7CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Trends

Current EPSS score: 0.02%• Percentile: 4%

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

    ≥ e5d82a7360d124ae1a38c2a5eac92ba49b125191, < 9a39f4626b361ee7aa10fd990401c37ec3b466ae | ≥ e5d82a7360d124ae1a38c2a5eac92ba49b125191, < 856e4b5e53f21edbd15d275dde62228dd94fb2b4 | ≥ e5d82a7360d124ae1a38c2a5eac92ba49b125191, < a2e075f40122d8daf587db126c562a67abd69cf9 | ≥ e5d82a7360d124ae1a38c2a5eac92ba49b125191, < 616fd34d017000ecf9097368b13d8a266f4920b3 | ≥ e5d82a7360d124ae1a38c2a5eac92ba49b125191, < d18dcfe9860e842f394e37ba01ca9440ab2178f4 | 5.3

  • linux•linux_kernel

    ≥ 5.3, < 5.4.230 | ≥ 5.5, < 5.10.165 | ≥ 5.11, < 5.15.90 | ≥ 5.16, < 6.1.8

References (5)