CVE-2024-53218: f2fs: fix race in concurrent f2fs_stop_gc_thread
First published: Fri Dec 27 2024(Updated: )
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix race in concurrent f2fs_stop_gc_thread In my test case, concurrent calls to f2fs shutdown report the following stack trace: Oops: general protection fault, probably for non-canonical address 0xc6cfff63bb5513fc: 0000 [#1] PREEMPT SMP PTI CPU: 0 UID: 0 PID: 678 Comm: f2fs_rep_shutdo Not tainted 6.12.0-rc5-next-20241029-g6fb2fa9805c5-dirty #85 Call Trace: <TASK> ? show_regs+0x8b/0xa0 ? __die_body+0x26/0xa0 ? die_addr+0x54/0x90 ? exc_general_protection+0x24b/0x5c0 ? asm_exc_general_protection+0x26/0x30 ? kthread_stop+0x46/0x390 f2fs_stop_gc_thread+0x6c/0x110 f2fs_do_shutdown+0x309/0x3a0 f2fs_ioc_shutdown+0x150/0x1c0 __f2fs_ioctl+0xffd/0x2ac0 f2fs_ioctl+0x76/0xe0 vfs_ioctl+0x23/0x60 __x64_sys_ioctl+0xce/0xf0 x64_sys_call+0x2b1b/0x4540 do_syscall_64+0xa7/0x240 entry_SYSCALL_64_after_hwframe+0x76/0x7e The root cause is a race condition in f2fs_stop_gc_thread() called from different f2fs shutdown paths: [CPU0] [CPU1] ---------------------- ----------------------- f2fs_stop_gc_thread f2fs_stop_gc_thread gc_th = sbi->gc_thread gc_th = sbi->gc_thread kfree(gc_th) sbi->gc_thread = NULL < gc_th != NULL > kthread_stop(gc_th->f2fs_gc_task) //UAF The commit c7f114d864ac ("f2fs: fix to avoid use-after-free in f2fs_stop_gc_thread()") attempted to fix this issue by using a read semaphore to prevent races between shutdown and remount threads, but it fails to prevent all race conditions. Fix it by converting to write lock of s_umount in f2fs_do_shutdown().
Credit: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
| Affected Software | Affected Version | How to fix |
|---|---|---|
| Linux kernel | ||
| debian/linux | <=5.10.223-1<=5.10.226-1<=6.1.123-1<=6.1.128-1 | 6.12.12-1 6.12.15-1 |
Never miss a vulnerability like this again
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.
Reference Links
- https://git.kernel.org/stable/c/794fa8792d4eacac191f1cbcc2e81b7369e4662a
- https://git.kernel.org/stable/c/60457ed6c67625c87861f96912b4179dc2293896
- https://git.kernel.org/stable/c/c631207897a9b3d41167ceca58e07f8f94720e42
- https://git.kernel.org/stable/c/7b0033dbc48340a1c1c3f12448ba17d6587ca092
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-53218
- https://nvd.nist.gov/vuln/detail/CVE-2024-53218
- https://launchpad.net/bugs/cve/CVE-2024-53218
- https://security-tracker.debian.org/tracker/CVE-2024-53218
- https://ubuntu.com/security/CVE-2024-53218
- https://git.kernel.org/linus/7b0033dbc48340a1c1c3f12448ba17d6587ca092
- agent/weakness
- agent/title
- agent/type
- agent/first-publish-date
- agent/author
- agent/guess-ai
- agent/software-canonical-lookup
- agent/software-canonical-lookup-request
- collector/mitre-cve
- source/MITRE
- collector/nvd-api
- source/NVD
- agent/severity
- agent/last-modified-date
- collector/usn-cve
- source/Ubuntu
- collector/nvd-cve
- collector/security-tracker-debian
- source/Debian
- agent/references
- agent/source
- agent/softwarecombine
- agent/tags
- agent/description
- agent/event
- vendor/linux
- canonical/linux kernel
- package-manager/debian