{"cve":"CVE-2023-53447","nvd":{"published":"2025-09-18T16:15:49.067","modified":"2026-10-30T13:17:18.473","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: don't reset unchangable mount option in f2fs_remount()\n\nsyzbot reports a bug as below:\n\ngeneral protection fault, probably for non-canonical address 0xdffffc0000000009: 0000 [#1] PREEMPT SMP KASAN\nRIP: 0010:__lock_acquire+0x69/0x2000 kernel/locking/lockdep.c:4942\nCall Trace:\n lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691\n __raw_write_lock include/linux/rwlock_api_smp.h:209 [inline]\n _raw_write_lock+0x2e/0x40 kernel/locking/spinlock.c:300\n __drop_extent_tree+0x3ac/0x660 fs/f2fs/extent_cache.c:1100\n f2fs_drop_extent_tree+0x17/0x30 fs/f2fs/extent_cache.c:1116\n f2fs_insert_range+0x2d5/0x3c0 fs/f2fs/file.c:1664\n f2fs_fallocate+0x4e4/0x6d0 fs/f2fs/file.c:1838\n vfs_fallocate+0x54b/0x6b0 fs/open.c:324\n ksys_fallocate fs/open.c:347 [inline]\n __do_sys_fallocate fs/open.c:355 [inline]\n __se_sys_fallocate fs/open.c:353 [inline]\n __x64_sys_fallocate+0xbd/0x100 fs/open.c:353\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nThe root cause is race condition as below:\n- since it tries to remount rw filesystem, so that do_remount won't\ncall sb_prepare_remount_readonly to block fallocate, there may be race\ncondition in between remount and fallocate.\n- in f2fs_remount(), default_options() will reset mount option to default\none, and then update it based on result of parse_options(), so there is\na hole which race condition can happen.\n\nThread A\t\t\tThread B\n- f2fs_fill_super\n - parse_options\n  - clear_opt(READ_EXTENT_CACHE)\n\n- f2fs_remount\n - default_options\n  - set_opt(READ_EXTENT_CACHE)\n\t\t\t\t- f2fs_fallocate\n\t\t\t\t - f2fs_insert_range\n\t\t\t\t  - f2fs_drop_extent_tree\n\t\t\t\t   - __drop_extent_tree\n\t\t\t\t    - __may_extent_tree\n\t\t\t\t     - test_opt(READ_EXTENT_CACHE) return true\n\t\t\t\t    - write_lock(&et->lock) access NULL pointer\n - parse_options\n  - clear_opt(READ_EXTENT_CACHE)","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","score":4.7},"cwes":["CWE-362"],"references":["https://git.kernel.org/stable/c/115557cc226a927924f2d7d1980ccbf6e3b3bb36","https://git.kernel.org/stable/c/458c15dfbce62c35fefd9ca637b20a051309c9f1","https://git.kernel.org/stable/c/f6464b3c31344af4964443dbbcb4596ac9b46519"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-30T13:47:47.119061695+00:00"},"epss":{"cve":"CVE-2023-53447","score":0.00095,"percentile":0.00605,"date":"2026-10-30"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}