{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-50752","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-12-24T13:02:21.544Z","datePublished":"2025-12-24T13:05:46.881Z","dateUpdated":"2026-08-05T08:59:39.128Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T08:59:39.128Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmd/raid5: Remove unnecessary bio_put() in raid5_read_one_chunk()\n\nWhen running chunk-sized reads on disks with badblocks duplicate bio\nfree/puts are observed:\n\n   =============================================================================\n   BUG bio-200 (Not tainted): Object already free\n   -----------------------------------------------------------------------------\n   Allocated in mempool_alloc_slab+0x17/0x20 age=3 cpu=2 pid=7504\n    __slab_alloc.constprop.0+0x5a/0xb0\n    kmem_cache_alloc+0x31e/0x330\n    mempool_alloc_slab+0x17/0x20\n    mempool_alloc+0x100/0x2b0\n    bio_alloc_bioset+0x181/0x460\n    do_mpage_readpage+0x776/0xd00\n    mpage_readahead+0x166/0x320\n    blkdev_readahead+0x15/0x20\n    read_pages+0x13f/0x5f0\n    page_cache_ra_unbounded+0x18d/0x220\n    force_page_cache_ra+0x181/0x1c0\n    page_cache_sync_ra+0x65/0xb0\n    filemap_get_pages+0x1df/0xaf0\n    filemap_read+0x1e1/0x700\n    blkdev_read_iter+0x1e5/0x330\n    vfs_read+0x42a/0x570\n   Freed in mempool_free_slab+0x17/0x20 age=3 cpu=2 pid=7504\n    kmem_cache_free+0x46d/0x490\n    mempool_free_slab+0x17/0x20\n    mempool_free+0x66/0x190\n    bio_free+0x78/0x90\n    bio_put+0x100/0x1a0\n    raid5_make_request+0x2259/0x2450\n    md_handle_request+0x402/0x600\n    md_submit_bio+0xd9/0x120\n    __submit_bio+0x11f/0x1b0\n    submit_bio_noacct_nocheck+0x204/0x480\n    submit_bio_noacct+0x32e/0xc70\n    submit_bio+0x98/0x1a0\n    mpage_readahead+0x250/0x320\n    blkdev_readahead+0x15/0x20\n    read_pages+0x13f/0x5f0\n    page_cache_ra_unbounded+0x18d/0x220\n   Slab 0xffffea000481b600 objects=21 used=0 fp=0xffff8881206d8940 flags=0x17ffffc0010201(locked|slab|head|node=0|zone=2|lastcpupid=0x1fffff)\n   CPU: 0 PID: 34525 Comm: kworker/u24:2 Not tainted 6.0.0-rc2-localyes-265166-gf11c5343fa3f #143\n   Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1.1 04/01/2014\n   Workqueue: raid5wq raid5_do_work\n   Call Trace:\n    <TASK>\n    dump_stack_lvl+0x5a/0x78\n    dump_stack+0x10/0x16\n    print_trailer+0x158/0x165\n    object_err+0x35/0x50\n    free_debug_processing.cold+0xb7/0xbe\n    __slab_free+0x1ae/0x330\n    kmem_cache_free+0x46d/0x490\n    mempool_free_slab+0x17/0x20\n    mempool_free+0x66/0x190\n    bio_free+0x78/0x90\n    bio_put+0x100/0x1a0\n    mpage_end_io+0x36/0x150\n    bio_endio+0x2fd/0x360\n    md_end_io_acct+0x7e/0x90\n    bio_endio+0x2fd/0x360\n    handle_failed_stripe+0x960/0xb80\n    handle_stripe+0x1348/0x3760\n    handle_active_stripes.constprop.0+0x72a/0xaf0\n    raid5_do_work+0x177/0x330\n    process_one_work+0x616/0xb20\n    worker_thread+0x2bd/0x6f0\n    kthread+0x179/0x1b0\n    ret_from_fork+0x22/0x30\n    </TASK>\n\nThe double free is caused by an unnecessary bio_put() in the\nif(is_badblock(...)) error path in raid5_read_one_chunk().\n\nThe error path was moved ahead of bio_alloc_clone() in c82aa1b76787c\n(\"md/raid5: move checking badblock before clone bio in\nraid5_read_one_chunk\"). The previous code checked and freed align_bio\nwhich required a bio_put. After the move that is no longer needed as\nraid_bio is returned to the control of the common io path which\nperforms its own endio resulting in a double free on bad device blocks."}],"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 path is reached through local block I/O to an md RAID5/6 device (raw /dev/md* or filesystem reads backed by the array) via md_submit_bio → raid5_make_request → raid5_read_one_chunk; md/raid5 is not itself a network protocol handler.\nAC:L - Once a non-degraded RAID5/6 array has badblocks on the target chunk, a chunk-aligned read reliably hits the is_badblock() path and the erroneous bio_put(); the attacker can discover badblock LBAs from world-readable sysfs and issue the reads directly, with no attacker-uncontrollable race.\nPR:L - Array creation and bad_blocks sysfs writes require CAP_SYS_ADMIN, but exploitation only requires issuing reads to an already-affected array (e.g., reading files on a RAID-backed filesystem or an accessible md block device), which an unprivileged local user can do.\nUI:N - The attacker triggers the bug by performing their own reads against the affected md device or filesystem; no separate victim action is required.\nS:U - This is standard host-kernel heap corruption within the same security authority as the md/block layer; it does not cross a VM, IOMMU, or other separate boundary.\nC:H - The bug frees the original bio then continues using it in the stripe path, which is a kernel slab use-after-free/double-free; per scoring guidance, UAF enables high-impact information disclosure primitives.\nI:H - Double-free of a bio slab object enables heap reuse and memory corruption suitable for control-flow hijacking or arbitrary write primitives; UAF/double-free warrants High integrity impact.\nA:H - The reported failure is a kernel slab 'Object already free' bug leading to oops/panic on the second bio_put during handle_failed_stripe completion; any such crash is High availability impact."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/md/raid5.c"],"versions":[{"version":"c82aa1b76787c34fd02374e519b6f52cdeb2f54b","lessThan":"7a37c58ee72e1fadd22c4ee990cb74c2ca2280e7","status":"affected","versionType":"git"},{"version":"c82aa1b76787c34fd02374e519b6f52cdeb2f54b","lessThan":"c0fd5d4d8fd7b1a50306d7a23c720cf808f41fdf","status":"affected","versionType":"git"},{"version":"c82aa1b76787c34fd02374e519b6f52cdeb2f54b","lessThan":"21a9c7354aa59e97e26ece5f0a609c8bfa43020d","status":"affected","versionType":"git"},{"version":"c82aa1b76787c34fd02374e519b6f52cdeb2f54b","lessThan":"c66a6f41e09ad386fd2cce22b9cded837bbbc704","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/md/raid5.c"],"versions":[{"version":"5.14","status":"affected"},{"version":"0","lessThan":"5.14","status":"unaffected","versionType":"semver"},{"version":"5.15.75","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"5.19.17","lessThanOrEqual":"5.19.*","status":"unaffected","versionType":"semver"},{"version":"6.0.3","lessThanOrEqual":"6.0.*","status":"unaffected","versionType":"semver"},{"version":"6.1","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":"5.14","versionEndExcluding":"5.15.75"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"5.19.17"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.0.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/7a37c58ee72e1fadd22c4ee990cb74c2ca2280e7"},{"url":"https://git.kernel.org/stable/c/c0fd5d4d8fd7b1a50306d7a23c720cf808f41fdf"},{"url":"https://git.kernel.org/stable/c/21a9c7354aa59e97e26ece5f0a609c8bfa43020d"},{"url":"https://git.kernel.org/stable/c/c66a6f41e09ad386fd2cce22b9cded837bbbc704"}],"title":"md/raid5: Remove unnecessary bio_put() in raid5_read_one_chunk()","x_generator":{"engine":"bippy-1.2.0"}}}}