{"id":"CVE-2024-47689","state":"PUBLISHED","title":"f2fs: fix to don't set SB_RDONLY in f2fs_handle_critical_error()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to don't set SB_RDONLY in f2fs_handle_critical_error()\n\nsyzbot reports a f2fs bug as below:\n\n------------[ cut here ]------------\nWARNING: CPU: 1 PID: 58 at kernel/rcu/sync.c:177 rcu_sync_dtor+0xcd/0x180 kernel/rcu/sync.c:177\nCPU: 1 UID: 0 PID: 58 Comm: kworker/1:2 Not tainted 6.10.0-syzkaller-12562-g1722389b0d86 #0\nWorkqueue: events destroy_super_work\nRIP: 0010:rcu_sync_dtor+0xcd/0x180 kernel/rcu/sync.c:177\nCall Trace:\n percpu_free_rwsem+0x41/0x80 kernel/locking/percpu-rwsem.c:42\n destroy_super_work+0xec/0x130 fs/super.c:282\n process_one_work kernel/workqueue.c:3231 [inline]\n process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312\n worker_thread+0x86d/0xd40 kernel/workqueue.c:3390\n kthread+0x2f0/0x390 kernel/kthread.c:389\n ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\n\nAs Christian Brauner pointed out [1]: the root cause is f2fs sets\nSB_RDONLY flag in internal function, rather than setting the flag\ncovered w/ sb->s_umount semaphore via remount procedure, then below\nrace condition causes this bug:\n\n- freeze_super()\n - sb_wait_write(sb, SB_FREEZE_WRITE)\n - sb_wait_write(sb, SB_FREEZE_PAGEFAULT)\n - sb_wait_write(sb, SB_FREEZE_FS)\n\t\t\t\t\t- f2fs_handle_critical_error\n\t\t\t\t\t - sb->s_flags |= SB_RDONLY\n- thaw_super\n - thaw_super_locked\n  - sb_rdonly() is true, so it skips\n    sb_freeze_unlock(sb, SB_FREEZE_FS)\n  - deactivate_locked_super\n\nSince f2fs has almost the same logic as ext4 [2] when handling critical\nerror in filesystem if it mounts w/ errors=remount-ro option:\n- set CP_ERROR_FLAG flag which indicates filesystem is stopped\n- record errors to superblock\n- set SB_RDONLY falg\nOnce we set CP_ERROR_FLAG flag, all writable interfaces can detect the\nflag and stop any further updates on filesystem. So, it is safe to not\nset SB_RDONLY flag, let's remove the logic and keep in line w/ ext4 [3].\n\n[1] https://lore.kernel.org/all/20240729-himbeeren-funknetz-96e62f9c7aee@brauner\n[2] https://lore.kernel.org/all/20240729132721.hxih6ehigadqf7wx@quack3\n[3] https://lore.kernel.org/linux-ext4/20240805201241.27286-1-jack@suse.cz","publishedAt":"2024-10-21T11:53:29.185Z","updatedAt":"2026-05-23T15:53:41.234Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"b62e71be2110d8b52bf5faf3c3ed7ca1a0c113a5","status":"affected","lessThan":"649ec8b30df113042588bd3d3cd4e98bcb1091e0","versionType":"git"},{"version":"b62e71be2110d8b52bf5faf3c3ed7ca1a0c113a5","status":"affected","lessThan":"de43021c72993877a8f86f9fddfa0687609da5a4","versionType":"git"},{"version":"b62e71be2110d8b52bf5faf3c3ed7ca1a0c113a5","status":"affected","lessThan":"1f63f405c1a1a64b9c310388aad7055fb86b245c","versionType":"git"},{"version":"b62e71be2110d8b52bf5faf3c3ed7ca1a0c113a5","status":"affected","lessThan":"930c6ab93492c4b15436524e704950b364b2930c","versionType":"git"},{"version":"ed1d478bf838820201f3fb67a1748fdf15954ea4","status":"affected","versionType":"git"},{"version":"6.4.4","status":"affected","lessThan":"6.5","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/f2fs/super.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.5","versionType":"semver"},{"version":"6.6.54","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.10.13","status":"unaffected","lessThanOrEqual":"6.10.*","versionType":"semver"},{"version":"6.11.2","status":"unaffected","lessThanOrEqual":"6.11.*","versionType":"semver"},{"version":"6.12","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/f2fs/super.c"]}],"references":["https://git.kernel.org/stable/c/649ec8b30df113042588bd3d3cd4e98bcb1091e0","https://git.kernel.org/stable/c/de43021c72993877a8f86f9fddfa0687609da5a4","https://git.kernel.org/stable/c/1f63f405c1a1a64b9c310388aad7055fb86b245c","https://git.kernel.org/stable/c/930c6ab93492c4b15436524e704950b364b2930c"],"weaknesses":[],"ingestedAt":"2026-10-29T20:07:56.516Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2024/47xxx/CVE-2024-47689.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-47689","state":"PUBLISHED","datePublished":"2024-10-21T11:53:29.185Z","dateUpdated":"2026-05-23T15:53:41.234Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-09-30T16:00:12.941Z"},"containers":{"cna":{"title":"f2fs: fix to don't set SB_RDONLY in f2fs_handle_critical_error()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to don't set SB_RDONLY in f2fs_handle_critical_error()\n\nsyzbot reports a f2fs bug as below:\n\n------------[ cut here ]------------\nWARNING: CPU: 1 PID: 58 at kernel/rcu/sync.c:177 rcu_sync_dtor+0xcd/0x180 kernel/rcu/sync.c:177\nCPU: 1 UID: 0 PID: 58 Comm: kworker/1:2 Not tainted 6.10.0-syzkaller-12562-g1722389b0d86 #0\nWorkqueue: events destroy_super_work\nRIP: 0010:rcu_sync_dtor+0xcd/0x180 kernel/rcu/sync.c:177\nCall Trace:\n percpu_free_rwsem+0x41/0x80 kernel/locking/percpu-rwsem.c:42\n destroy_super_work+0xec/0x130 fs/super.c:282\n process_one_work kernel/workqueue.c:3231 [inline]\n process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312\n worker_thread+0x86d/0xd40 kernel/workqueue.c:3390\n kthread+0x2f0/0x390 kernel/kthread.c:389\n ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\n\nAs Christian Brauner pointed out [1]: the root cause is f2fs sets\nSB_RDONLY flag in internal function, rather than setting the flag\ncovered w/ sb->s_umount semaphore via remount procedure, then below\nrace condition causes this bug:\n\n- freeze_super()\n - sb_wait_write(sb, SB_FREEZE_WRITE)\n - sb_wait_write(sb, SB_FREEZE_PAGEFAULT)\n - sb_wait_write(sb, SB_FREEZE_FS)\n\t\t\t\t\t- f2fs_handle_critical_error\n\t\t\t\t\t - sb->s_flags |= SB_RDONLY\n- thaw_super\n - thaw_super_locked\n  - sb_rdonly() is true, so it skips\n    sb_freeze_unlock(sb, SB_FREEZE_FS)\n  - deactivate_locked_super\n\nSince f2fs has almost the same logic as ext4 [2] when handling critical\nerror in filesystem if it mounts w/ errors=remount-ro option:\n- set CP_ERROR_FLAG flag which indicates filesystem is stopped\n- record errors to superblock\n- set SB_RDONLY falg\nOnce we set CP_ERROR_FLAG flag, all writable interfaces can detect the\nflag and stop any further updates on filesystem. So, it is safe to not\nset SB_RDONLY flag, let's remove the logic and keep in line w/ ext4 [3].\n\n[1] https://lore.kernel.org/all/20240729-himbeeren-funknetz-96e62f9c7aee@brauner\n[2] https://lore.kernel.org/all/20240729132721.hxih6ehigadqf7wx@quack3\n[3] https://lore.kernel.org/linux-ext4/20240805201241.27286-1-jack@suse.cz"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"b62e71be2110d8b52bf5faf3c3ed7ca1a0c113a5","status":"affected","lessThan":"649ec8b30df113042588bd3d3cd4e98bcb1091e0","versionType":"git"},{"version":"b62e71be2110d8b52bf5faf3c3ed7ca1a0c113a5","status":"affected","lessThan":"de43021c72993877a8f86f9fddfa0687609da5a4","versionType":"git"},{"version":"b62e71be2110d8b52bf5faf3c3ed7ca1a0c113a5","status":"affected","lessThan":"1f63f405c1a1a64b9c310388aad7055fb86b245c","versionType":"git"},{"version":"b62e71be2110d8b52bf5faf3c3ed7ca1a0c113a5","status":"affected","lessThan":"930c6ab93492c4b15436524e704950b364b2930c","versionType":"git"},{"version":"ed1d478bf838820201f3fb67a1748fdf15954ea4","status":"affected","versionType":"git"},{"version":"6.4.4","status":"affected","lessThan":"6.5","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/f2fs/super.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.5","versionType":"semver"},{"version":"6.6.54","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.10.13","status":"unaffected","lessThanOrEqual":"6.10.*","versionType":"semver"},{"version":"6.11.2","status":"unaffected","lessThanOrEqual":"6.11.*","versionType":"semver"},{"version":"6.12","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/f2fs/super.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/649ec8b30df113042588bd3d3cd4e98bcb1091e0"},{"url":"https://git.kernel.org/stable/c/de43021c72993877a8f86f9fddfa0687609da5a4"},{"url":"https://git.kernel.org/stable/c/1f63f405c1a1a64b9c310388aad7055fb86b245c"},{"url":"https://git.kernel.org/stable/c/930c6ab93492c4b15436524e704950b364b2930c"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-23T15:53:41.234Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.5","versionEndExcluding":"6.6.54"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.5","versionEndExcluding":"6.10.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.5","versionEndExcluding":"6.11.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.5","versionEndExcluding":"6.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4.4"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2024-47689","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-10-21T13:06:11.931921Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-10-21T13:14:15.437Z"}}]}}}