{"id":"CVE-2024-53218","summary":"f2fs: fix race in concurrent f2fs_stop_gc_thread","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix race in concurrent f2fs_stop_gc_thread\n\nIn my test case, concurrent calls to f2fs shutdown report the following\nstack trace:\n\n Oops: general protection fault, probably for non-canonical address 0xc6cfff63bb5513fc: 0000 [#1] PREEMPT SMP PTI\n CPU: 0 UID: 0 PID: 678 Comm: f2fs_rep_shutdo Not tainted 6.12.0-rc5-next-20241029-g6fb2fa9805c5-dirty #85\n Call Trace:\n  \u003cTASK\u003e\n  ? show_regs+0x8b/0xa0\n  ? __die_body+0x26/0xa0\n  ? die_addr+0x54/0x90\n  ? exc_general_protection+0x24b/0x5c0\n  ? asm_exc_general_protection+0x26/0x30\n  ? kthread_stop+0x46/0x390\n  f2fs_stop_gc_thread+0x6c/0x110\n  f2fs_do_shutdown+0x309/0x3a0\n  f2fs_ioc_shutdown+0x150/0x1c0\n  __f2fs_ioctl+0xffd/0x2ac0\n  f2fs_ioctl+0x76/0xe0\n  vfs_ioctl+0x23/0x60\n  __x64_sys_ioctl+0xce/0xf0\n  x64_sys_call+0x2b1b/0x4540\n  do_syscall_64+0xa7/0x240\n  entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nThe root cause is a race condition in f2fs_stop_gc_thread() called from\ndifferent f2fs shutdown paths:\n\n  [CPU0]                       [CPU1]\n  ----------------------       -----------------------\n  f2fs_stop_gc_thread          f2fs_stop_gc_thread\n                                 gc_th = sbi-\u003egc_thread\n    gc_th = sbi-\u003egc_thread\n    kfree(gc_th)\n    sbi-\u003egc_thread = NULL\n                                 \u003c gc_th != NULL \u003e\n                                 kthread_stop(gc_th-\u003ef2fs_gc_task) //UAF\n\nThe commit c7f114d864ac (\"f2fs: fix to avoid use-after-free in\nf2fs_stop_gc_thread()\") attempted to fix this issue by using a read\nsemaphore to prevent races between shutdown and remount threads, but\nit fails to prevent all race conditions.\n\nFix it by converting to write lock of s_umount in f2fs_do_shutdown().","modified":"2026-04-02T12:23:01.010861Z","published":"2024-12-27T13:50:03.556Z","related":["USN-7276-1","USN-7277-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/53xxx/CVE-2024-53218.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/60457ed6c67625c87861f96912b4179dc2293896"},{"type":"WEB","url":"https://git.kernel.org/stable/c/794fa8792d4eacac191f1cbcc2e81b7369e4662a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7b0033dbc48340a1c1c3f12448ba17d6587ca092"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c631207897a9b3d41167ceca58e07f8f94720e42"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/53xxx/CVE-2024-53218.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-53218"},{"type":"PACKAGE","url":"https://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":[{"introduced":"7950e9ac638e84518fbdd5c930939ad46a1068c5"},{"fixed":"794fa8792d4eacac191f1cbcc2e81b7369e4662a"},{"fixed":"60457ed6c67625c87861f96912b4179dc2293896"},{"fixed":"c631207897a9b3d41167ceca58e07f8f94720e42"},{"fixed":"7b0033dbc48340a1c1c3f12448ba17d6587ca092"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-53218.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}