{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2024-42266",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-07-30T07:40:12.259Z",
        "datePublished": "2024-08-17T08:54:22.308Z",
        "dateUpdated": "2026-08-05T11:36:11.043Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T11:36:11.043Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: make cow_file_range_inline() honor locked_page on error\n\nThe btrfs buffered write path runs through __extent_writepage() which\nhas some tricky return value handling for writepage_delalloc().\nSpecifically, when that returns 1, we exit, but for other return values\nwe continue and end up calling btrfs_folio_end_all_writers(). If the\nfolio has been unlocked (note that we check the PageLocked bit at the\nstart of __extent_writepage()), this results in an assert panic like\nthis one from syzbot:\n\n  BTRFS: error (device loop0 state EAL) in free_log_tree:3267: errno=-5 IO failure\n  BTRFS warning (device loop0 state EAL): Skipping commit of aborted transaction.\n  BTRFS: error (device loop0 state EAL) in cleanup_transaction:2018: errno=-5 IO failure\n  assertion failed: folio_test_locked(folio), in fs/btrfs/subpage.c:871\n  ------------[ cut here ]------------\n  kernel BUG at fs/btrfs/subpage.c:871!\n  Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI\n  CPU: 1 PID: 5090 Comm: syz-executor225 Not tainted\n  6.10.0-syzkaller-05505-gb1bc554e009e #0\n  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS\n  Google 06/27/2024\n  RIP: 0010:btrfs_folio_end_all_writers+0x55b/0x610 fs/btrfs/subpage.c:871\n  Code: e9 d3 fb ff ff e8 25 22 c2 fd 48 c7 c7 c0 3c 0e 8c 48 c7 c6 80 3d\n  0e 8c 48 c7 c2 60 3c 0e 8c b9 67 03 00 00 e8 66 47 ad 07 90 <0f> 0b e8\n  6e 45 b0 07 4c 89 ff be 08 00 00 00 e8 21 12 25 fe 4c 89\n  RSP: 0018:ffffc900033d72e0 EFLAGS: 00010246\n  RAX: 0000000000000045 RBX: 00fff0000000402c RCX: 663b7a08c50a0a00\n  RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000\n  RBP: ffffc900033d73b0 R08: ffffffff8176b98c R09: 1ffff9200067adfc\n  R10: dffffc0000000000 R11: fffff5200067adfd R12: 0000000000000001\n  R13: dffffc0000000000 R14: 0000000000000000 R15: ffffea0001cbee80\n  FS:  0000000000000000(0000) GS:ffff8880b9500000(0000)\n  knlGS:0000000000000000\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  CR2: 00007f5f076012f8 CR3: 000000000e134000 CR4: 00000000003506f0\n  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n  Call Trace:\n  <TASK>\n  __extent_writepage fs/btrfs/extent_io.c:1597 [inline]\n  extent_write_cache_pages fs/btrfs/extent_io.c:2251 [inline]\n  btrfs_writepages+0x14d7/0x2760 fs/btrfs/extent_io.c:2373\n  do_writepages+0x359/0x870 mm/page-writeback.c:2656\n  filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:397\n  __filemap_fdatawrite_range mm/filemap.c:430 [inline]\n  __filemap_fdatawrite mm/filemap.c:436 [inline]\n  filemap_flush+0xdf/0x130 mm/filemap.c:463\n  btrfs_release_file+0x117/0x130 fs/btrfs/file.c:1547\n  __fput+0x24a/0x8a0 fs/file_table.c:422\n  task_work_run+0x24f/0x310 kernel/task_work.c:222\n  exit_task_work include/linux/task_work.h:40 [inline]\n  do_exit+0xa2f/0x27f0 kernel/exit.c:877\n  do_group_exit+0x207/0x2c0 kernel/exit.c:1026\n  __do_sys_exit_group kernel/exit.c:1037 [inline]\n  __se_sys_exit_group kernel/exit.c:1035 [inline]\n  __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1035\n  x64_sys_call+0x2634/0x2640\n  arch/x86/include/generated/asm/syscalls_64.h:232\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: 0033:0x7f5f075b70c9\n  Code: Unable to access opcode bytes at\n  0x7f5f075b709f.\n\nI was hitting the same issue by doing hundreds of accelerated runs of\ngeneric/475, which also hits IO errors by design.\n\nI instrumented that reproducer with bpftrace and found that the\nundesirable folio_unlock was coming from the following callstack:\n\n  folio_unlock+5\n  __process_pages_contig+475\n  cow_file_range_inline.constprop.0+230\n  cow_file_range+803\n  btrfs_run_delalloc_range+566\n  writepage_delalloc+332\n  __extent_writepage # inlined in my stacktrace, but I added it here\n  extent_write_cache_pages+622\n\nLooking at the bisected-to pa\n---truncated---"
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 7.8,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:L - The vulnerable code is the btrfs buffered-write/writeback path, reached through ordinary local syscalls (write/close/fsync) on a mounted btrfs filesystem. No network protocol handling is involved, so local access to the machine is required.\nAC:L - The attacker fully controls the trigger — create a small (<=2048 byte) file at offset 0 so the inline-extent path is taken, and drive cow_file_range_inline() to a negative return via attacker-inducible memory pressure (-ENOMEM in btrfs_alloc_path/btrfs_join_transaction) or on an already-aborted/EROFS filesystem where the failure is deterministic; the write/close loop can be repeated indefinitely until it fires.\nPR:L - Any unprivileged local user with write access to any btrfs filesystem (e.g. /home or /tmp) can reach the path; no capabilities, mount privileges, or user-namespace tricks are needed.\nUI:N - The attacker's own write and close trigger writeback via btrfs_release_file()->filemap_flush(), exactly as in the syzbot stack trace; no victim action is required.\nS:U - The corrupted state (folio lock bits, btrfs page-cache pages) and the resulting panic or hang are confined to the kernel of the same host, with no crossing of a VM, IOMMU, or other security authority boundary.\nC:H - The double unlock destroys page-lock mutual exclusion on a page-cache folio, letting a second thread operate on a folio concurrently with truncate/invalidate/reclaim and read data from a folio that can be freed and reused underneath it, a use-after-free style read primitive over page cache contents.\nI:H - With the page lock invariant broken, two threads can simultaneously believe they own a folio that is being started into writeback, allowing writes into a folio racing removal from the mapping and reuse, i.e. memory corruption leveragable beyond a mere crash.\nA:H - On kernels with CONFIG_BTRFS_ASSERT this is an immediate kernel BUG/panic at fs/btrfs/subpage.c:871; otherwise folio_unlock()'s xor re-sets PG_locked on an ownerless folio, wedging every future access to that page in an unkillable D-state and blocking inode eviction and unmount."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/btrfs/inode.c"
                    ],
                    "versions": [
                        {
                            "version": "0586d0a89e77d717da14df42648ace4a9fd67981",
                            "lessThan": "061e41581606000a83ce0f0f01d6ad338f3704e9",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "0586d0a89e77d717da14df42648ace4a9fd67981",
                            "lessThan": "478574370bef7951fbd9ef5155537d6cbed49472",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/btrfs/inode.c"
                    ],
                    "versions": [
                        {
                            "version": "6.10",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.10",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.10.4",
                            "lessThanOrEqual": "6.10.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.11",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "6.10.4"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.10",
                                    "versionEndExcluding": "6.11"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/061e41581606000a83ce0f0f01d6ad338f3704e9"
                },
                {
                    "url": "https://git.kernel.org/stable/c/478574370bef7951fbd9ef5155537d6cbed49472"
                }
            ],
            "title": "btrfs: make cow_file_range_inline() honor locked_page on error",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2024-42266",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "version": "2.0.3",
                                "timestamp": "2024-09-10T16:12:27.580534Z"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2024-09-12T17:33:05.700Z"
                }
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    }
}