cvelist/2024/42xxx/CVE-2024-42111.json

{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2024-42111",
        "ASSIGNER": "cve@kernel.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: always do the basic checks for btrfs_qgroup_inherit structure\n\n[BUG]\nSyzbot reports the following regression detected by KASAN:\n\n  BUG: KASAN: slab-out-of-bounds in btrfs_qgroup_inherit+0x42e/0x2e20 fs/btrfs/qgroup.c:3277\n  Read of size 8 at addr ffff88814628ca50 by task syz-executor318/5171\n\n  CPU: 0 PID: 5171 Comm: syz-executor318 Not tainted 6.10.0-rc2-syzkaller-00010-g2ab795141095 #0\n  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024\n  Call Trace:\n   <TASK>\n   __dump_stack lib/dump_stack.c:88 [inline]\n   dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114\n   print_address_description mm/kasan/report.c:377 [inline]\n   print_report+0x169/0x550 mm/kasan/report.c:488\n   kasan_report+0x143/0x180 mm/kasan/report.c:601\n   btrfs_qgroup_inherit+0x42e/0x2e20 fs/btrfs/qgroup.c:3277\n   create_pending_snapshot+0x1359/0x29b0 fs/btrfs/transaction.c:1854\n   create_pending_snapshots+0x195/0x1d0 fs/btrfs/transaction.c:1922\n   btrfs_commit_transaction+0xf20/0x3740 fs/btrfs/transaction.c:2382\n   create_snapshot+0x6a1/0x9e0 fs/btrfs/ioctl.c:875\n   btrfs_mksubvol+0x58f/0x710 fs/btrfs/ioctl.c:1029\n   btrfs_mksnapshot+0xb5/0xf0 fs/btrfs/ioctl.c:1075\n   __btrfs_ioctl_snap_create+0x387/0x4b0 fs/btrfs/ioctl.c:1340\n   btrfs_ioctl_snap_create_v2+0x1f2/0x3a0 fs/btrfs/ioctl.c:1422\n   btrfs_ioctl+0x99e/0xc60\n   vfs_ioctl fs/ioctl.c:51 [inline]\n   __do_sys_ioctl fs/ioctl.c:907 [inline]\n   __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893\n   do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n   do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n  RIP: 0033:0x7fcbf1992509\n  RSP: 002b:00007fcbf1928218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010\n  RAX: ffffffffffffffda RBX: 00007fcbf1a1f618 RCX: 00007fcbf1992509\n  RDX: 0000000020000280 RSI: 0000000050009417 RDI: 0000000000000003\n  RBP: 00007fcbf1a1f610 R08: 00007ffea1298e97 R09: 0000000000000000\n  R10: 0000000000000000 R11: 0000000000000246 R12: 00007fcbf19eb660\n  R13: 00000000200002b8 R14: 00007fcbf19e60c0 R15: 0030656c69662f2e\n   </TASK>\n\nAnd it also pinned it down to commit b5357cb268c4 (\"btrfs: qgroup: do not\ncheck qgroup inherit if qgroup is disabled\").\n\n[CAUSE]\nThat offending commit skips the whole qgroup inherit check if qgroup is\nnot enabled.\n\nBut that also skips the very basic checks like\nnum_ref_copies/num_excl_copies and the structure size checks.\n\nMeaning if a qgroup enable/disable race is happening at the background,\nand we pass a btrfs_qgroup_inherit structure when the qgroup is\ndisabled, the check would be completely skipped.\n\nThen at the time of transaction commitment, qgroup is re-enabled and\nbtrfs_qgroup_inherit() is going to use the incorrect structure and\ncausing the above KASAN error.\n\n[FIX]\nMake btrfs_qgroup_check_inherit() only skip the source qgroup checks.\nSo that even if invalid btrfs_qgroup_inherit structure is passed in, we\ncan still reject invalid ones no matter if qgroup is enabled or not.\n\nFurthermore we do already have an extra safety inside\nbtrfs_qgroup_inherit(), which would just ignore invalid qgroup sources,\nso even if we only skip the qgroup source check we're still safe."
            }
        ]
    },
    "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": "b5357cb268c4",
                                            "version_value": "ebe5ea02577b"
                                        },
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "version": "6.9",
                                                        "status": "affected"
                                                    },
                                                    {
                                                        "version": "0",
                                                        "lessThan": "6.9",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.9.9",
                                                        "lessThanOrEqual": "6.9.*",
                                                        "status": "unaffected",
                                                        "versionType": "custom"
                                                    },
                                                    {
                                                        "version": "6.10",
                                                        "lessThanOrEqual": "*",
                                                        "status": "unaffected",
                                                        "versionType": "original_commit_for_fix"
                                                    }
                                                ],
                                                "defaultStatus": "affected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
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    "references": {
        "reference_data": [
            {
                "url": "https://git.kernel.org/stable/c/ebe5ea02577b2c527958af1b76ac472c7ab53a56",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/ebe5ea02577b2c527958af1b76ac472c7ab53a56"
            },
            {
                "url": "https://git.kernel.org/stable/c/724d8042cef84496ddb4492dc120291f997ae26b",
                "refsource": "MISC",
                "name": "https://git.kernel.org/stable/c/724d8042cef84496ddb4492dc120291f997ae26b"
            }
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