{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2024-50225",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2024-10-21T19:36:19.973Z",
        "datePublished": "2024-11-09T10:14:36.065Z",
        "dateUpdated": "2026-08-05T11:42:37.937Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T11:42:37.937Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: fix error propagation of split bios\n\nThe purpose of btrfs_bbio_propagate_error() shall be propagating an error\nof split bio to its original btrfs_bio, and tell the error to the upper\nlayer. However, it's not working well on some cases.\n\n* Case 1. Immediate (or quick) end_bio with an error\n\nWhen btrfs sends btrfs_bio to mirrored devices, btrfs calls\nbtrfs_bio_end_io() when all the mirroring bios are completed. If that\nbtrfs_bio was split, it is from btrfs_clone_bioset and its end_io function\nis btrfs_orig_write_end_io. For this case, btrfs_bbio_propagate_error()\naccesses the orig_bbio's bio context to increase the error count.\n\nThat works well in most cases. However, if the end_io is called enough\nfast, orig_bbio's (remaining part after split) bio context may not be\nproperly set at that time. Since the bio context is set when the orig_bbio\n(the last btrfs_bio) is sent to devices, that might be too late for earlier\nsplit btrfs_bio's completion.  That will result in NULL pointer\ndereference.\n\nThat bug is easily reproducible by running btrfs/146 on zoned devices [1]\nand it shows the following trace.\n\n[1] You need raid-stripe-tree feature as it create \"-d raid0 -m raid1\" FS.\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000020\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 0 P4D 0\n  Oops: Oops: 0000 [#1] PREEMPT SMP PTI\n  CPU: 1 UID: 0 PID: 13 Comm: kworker/u32:1 Not tainted 6.11.0-rc7-BTRFS-ZNS+ #474\n  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n  Workqueue: writeback wb_workfn (flush-btrfs-5)\n  RIP: 0010:btrfs_bio_end_io+0xae/0xc0 [btrfs]\n  BTRFS error (device dm-0): bdev /dev/mapper/error-test errs: wr 2, rd 0, flush 0, corrupt 0, gen 0\n  RSP: 0018:ffffc9000006f248 EFLAGS: 00010246\n  RAX: 0000000000000000 RBX: ffff888005a7f080 RCX: ffffc9000006f1dc\n  RDX: 0000000000000000 RSI: 000000000000000a RDI: ffff888005a7f080\n  RBP: ffff888011dfc540 R08: 0000000000000000 R09: 0000000000000001\n  R10: ffffffff82e508e0 R11: 0000000000000005 R12: ffff88800ddfbe58\n  R13: ffff888005a7f080 R14: ffff888005a7f158 R15: ffff888005a7f158\n  FS:  0000000000000000(0000) GS:ffff88803ea80000(0000) knlGS:0000000000000000\n  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n  CR2: 0000000000000020 CR3: 0000000002e22006 CR4: 0000000000370ef0\n  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n  Call Trace:\n   <TASK>\n   ? __die_body.cold+0x19/0x26\n   ? page_fault_oops+0x13e/0x2b0\n   ? _printk+0x58/0x73\n   ? do_user_addr_fault+0x5f/0x750\n   ? exc_page_fault+0x76/0x240\n   ? asm_exc_page_fault+0x22/0x30\n   ? btrfs_bio_end_io+0xae/0xc0 [btrfs]\n   ? btrfs_log_dev_io_error+0x7f/0x90 [btrfs]\n   btrfs_orig_write_end_io+0x51/0x90 [btrfs]\n   dm_submit_bio+0x5c2/0xa50 [dm_mod]\n   ? find_held_lock+0x2b/0x80\n   ? blk_try_enter_queue+0x90/0x1e0\n   __submit_bio+0xe0/0x130\n   ? ktime_get+0x10a/0x160\n   ? lockdep_hardirqs_on+0x74/0x100\n   submit_bio_noacct_nocheck+0x199/0x410\n   btrfs_submit_bio+0x7d/0x150 [btrfs]\n   btrfs_submit_chunk+0x1a1/0x6d0 [btrfs]\n   ? lockdep_hardirqs_on+0x74/0x100\n   ? __folio_start_writeback+0x10/0x2c0\n   btrfs_submit_bbio+0x1c/0x40 [btrfs]\n   submit_one_bio+0x44/0x60 [btrfs]\n   submit_extent_folio+0x13f/0x330 [btrfs]\n   ? btrfs_set_range_writeback+0xa3/0xd0 [btrfs]\n   extent_writepage_io+0x18b/0x360 [btrfs]\n   extent_write_locked_range+0x17c/0x340 [btrfs]\n   ? __pfx_end_bbio_data_write+0x10/0x10 [btrfs]\n   run_delalloc_cow+0x71/0xd0 [btrfs]\n   btrfs_run_delalloc_range+0x176/0x500 [btrfs]\n   ? find_lock_delalloc_range+0x119/0x260 [btrfs]\n   writepage_delalloc+0x2ab/0x480 [btrfs]\n   extent_write_cache_pages+0x236/0x7d0 [btrfs]\n   btrfs_writepages+0x72/0x130 [btrfs]\n   do_writepages+0xd4/0x240\n   ? find_held_lock+0x2b/0x80\n   ? wbc_attach_and_unlock_inode+0x12c/0x290\n   ? wbc_attach_and_unlock_inode+0x12c/0x29\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 bio submission/completion path reached through ordinary local file writes and writeback on a mounted btrfs filesystem (btrfs_writepages → btrfs_submit_bbio → btrfs_bio_end_io); there is no network-facing entry point.\nAC:L - On a degraded or removable multi-device btrfs, btrfs_submit_dev_bio() takes the synchronous bio_io_error() path, so the split bio completes with an error before the original bbio is ever submitted — a deterministic NULL bi_private dereference, not a race; where a race is involved (zoned/RST, Case 2 early completion) the attacker controls the write volume and pattern that drive both sides, and the upstream reproducer (btrfs/146) hits it easily.\nPR:L - Any unprivileged local user with write access to a btrfs filesystem generates the delalloc/writeback bios that get split; no capability, ioctl privilege, or admin check exists anywhere along the path from write(2) to btrfs_bbio_propagate_error().\nUI:N - The faulting code runs asynchronously in a writeback kworker after the attacker's writes; no victim action, mount, or file open by another user is required.\nS:U - The corruption and crash are confined to the kernel's own memory and the filesystem it manages, with no crossing of a VM, IOMMU, or other security-authority boundary.\nC:H - Beyond the NULL dereference, an early-completing original bbio causes btrfs_put_bioc() to free the btrfs_io_context while a split bio is still in flight, so orig_stripe->bioc is read out of freed (potentially reallocated and heap-groomed) slab memory — memory corruption leverageable for kernel information disclosure.\nI:H - The stale-pointer path performs atomic_add(orig_bioc->max_errors, &orig_bioc->error) through a pointer read from freed memory, yielding a write primitive at an attacker-influenceable kernel address; independently, the broken propagation silently reports failed data and metadata writes as BLK_STS_OK, so writeback and fsync succeed for data never persisted.\nA:H - The confirmed failure mode is a kernel NULL pointer dereference oops at address 0x20 inside a writeback kworker (killing the thread while holding writeback/ordered-extent state, wedging the filesystem), and the use-after-free variant likewise leads to panics."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/btrfs/bio.c",
                        "fs/btrfs/bio.h"
                    ],
                    "versions": [
                        {
                            "version": "852eee62d31abd695cd43e1b875d664ed292a8ca",
                            "lessThan": "22833d89b780ba0f9f66e19c477e7decf638edce",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "852eee62d31abd695cd43e1b875d664ed292a8ca",
                            "lessThan": "d48e1dea3931de64c26717adc2b89743c7ab6594",
                            "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/bio.c",
                        "fs/btrfs/bio.h"
                    ],
                    "versions": [
                        {
                            "version": "6.3",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.3",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.11.7",
                            "lessThanOrEqual": "6.11.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12",
                            "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": "6.3",
                                    "versionEndExcluding": "6.11.7"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.3",
                                    "versionEndExcluding": "6.12"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/22833d89b780ba0f9f66e19c477e7decf638edce"
                },
                {
                    "url": "https://git.kernel.org/stable/c/d48e1dea3931de64c26717adc2b89743c7ab6594"
                }
            ],
            "title": "btrfs: fix error propagation of split bios",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "cvssV3_1": {
                            "scope": "UNCHANGED",
                            "version": "3.1",
                            "baseScore": 5.5,
                            "attackVector": "LOCAL",
                            "baseSeverity": "MEDIUM",
                            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                            "integrityImpact": "NONE",
                            "userInteraction": "NONE",
                            "attackComplexity": "LOW",
                            "availabilityImpact": "HIGH",
                            "privilegesRequired": "LOW",
                            "confidentialityImpact": "NONE"
                        }
                    },
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "id": "CVE-2024-50225",
                                "role": "CISA Coordinator",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "version": "2.0.3",
                                "timestamp": "2025-10-01T20:16:54.858322Z"
                            }
                        }
                    }
                ],
                "problemTypes": [
                    {
                        "descriptions": [
                            {
                                "lang": "en",
                                "type": "CWE",
                                "cweId": "CWE-476",
                                "description": "CWE-476 NULL Pointer Dereference"
                            }
                        ]
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2025-10-01T20:17:28.196Z"
                }
            }
        ]
    }
}