cvelist/2024/47xxx/CVE-2024-47689.json

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    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-47689",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "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"
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Linux",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Linux",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "b62e71be2110",
                                            "version_value": "649ec8b30df1"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "6.5",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "6.5",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "6.6.54",
                                                        "lessThanOrEqual": "6.6.*",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "6.10.13",
                                                        "lessThanOrEqual": "6.10.*",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "6.11.2",
                                                        "lessThanOrEqual": "6.11.*",
                                                        "status": "unaffected",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "version": "6.12",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
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                                                ],
                                                "defaultStatus": "affected"
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    "references": {
        "reference_data": [
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                "url": "https://git.kernel.org/stable/c/649ec8b30df113042588bd3d3cd4e98bcb1091e0",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/649ec8b30df113042588bd3d3cd4e98bcb1091e0"
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                "url": "https://git.kernel.org/stable/c/de43021c72993877a8f86f9fddfa0687609da5a4",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/de43021c72993877a8f86f9fddfa0687609da5a4"
            },
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                "url": "https://git.kernel.org/stable/c/1f63f405c1a1a64b9c310388aad7055fb86b245c",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/1f63f405c1a1a64b9c310388aad7055fb86b245c"
            },
            {
                "url": "https://git.kernel.org/stable/c/930c6ab93492c4b15436524e704950b364b2930c",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/930c6ab93492c4b15436524e704950b364b2930c"
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