{"id":"CVE-2024-53166","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nblock, bfq: fix bfqq uaf in bfq_limit_depth()\n\nSet new allocated bfqq to bic or remove freed bfqq from bic are both\nprotected by bfqd->lock, however bfq_limit_depth() i…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nblock, bfq: fix bfqq uaf in bfq_limit_depth()\n\nSet new allocated bfqq to bic or remove freed bfqq from bic are both\nprotected by bfqd->lock, however bfq_limit_depth() i…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-416"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 5.17, < 6.6.64","linux_kernel >= 6.7, < 6.11.11","linux_kernel >= 6.12, < 6.12.2"],"patched":["linux_kernel 6.12.2"],"published":"2024-12-27","updated":"2026-10-15","sourceUpdated":"2026-10-15T01:19:15.150","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2024-53166","references":[{"url":"https://git.kernel.org/stable/c/01a853faaeaf3379ccf358ade582b1d28752126e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/906cdbdd3b018ff69cc830173bce277a847d4fdc","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ada4ca5fd5a9d5212f28164d49a4885951c979c9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/dcaa738afde55085ac6056252e319479cf23cde2","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e8b8344de3980709080d86c157d24e7de07d70ad","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-082556.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00259,"epssPercentile":0.17508,"ingestedAt":"2026-10-15T03:30:12.772Z","ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2025-02-10T17:13:21.417315Z"},"slug":"CVE-2024-53166","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nblock, bfq: fix bfqq uaf in bfq_limit_depth()\n\nSet new allocated bfqq to bic or remove freed bfqq from bic are both\nprotected by bfqd->lock, however bfq_limit_depth() is deferencing bfqq\nfrom bic without the lock, this can lead to UAF if the io_context is\nshared by multiple tasks.\n\nFor example, test bfq with io_uring can trigger following UAF in v6.6:\n\n==================================================================\nBUG: KASAN: slab-use-after-free in bfqq_group+0x15/0x50\n\nCall Trace:\n <TASK>\n dump_stack_lvl+0x47/0x80\n print_address_description.constprop.0+0x66/0x300\n print_report+0x3e/0x70\n kasan_report+0xb4/0xf0\n bfqq_group+0x15/0x50\n bfqq_request_over_limit+0x130/0x9a0\n bfq_limit_depth+0x1b5/0x480\n __blk_mq_alloc_requests+0x2b5/0xa00\n blk_mq_get_new_requests+0x11d/0x1d0\n blk_mq_submit_bio+0x286/0xb00\n submit_bio_noacct_nocheck+0x331/0x400\n __block_write_full_folio+0x3d0/0x640\n writepage_cb+0x3b/0xc0\n write_cache_pages+0x254/0x6c0\n write_cache_pages+0x254/0x6c0\n do_writepages+0x192/0x310\n filemap_fdatawrite_wbc+0x95/0xc0\n __filemap_fdatawrite_range+0x99/0xd0\n filemap_write_and_wait_range.part.0+0x4d/0xa0\n blkdev_read_iter+0xef/0x1e0\n io_read+0x1b6/0x8a0\n io_issue_sqe+0x87/0x300\n io_wq_submit_work+0xeb/0x390\n io_worker_handle_work+0x24d/0x550\n io_wq_worker+0x27f/0x6c0\n ret_from_fork_asm+0x1b/0x30\n </TASK>\n\nAllocated by task 808602:\n kasan_save_stack+0x1e/0x40\n kasan_set_track+0x21/0x30\n __kasan_slab_alloc+0x83/0x90\n kmem_cache_alloc_node+0x1b1/0x6d0\n bfq_get_queue+0x138/0xfa0\n bfq_get_bfqq_handle_split+0xe3/0x2c0\n bfq_init_rq+0x196/0xbb0\n bfq_insert_request.isra.0+0xb5/0x480\n bfq_insert_requests+0x156/0x180\n blk_mq_insert_request+0x15d/0x440\n blk_mq_submit_bio+0x8a4/0xb00\n submit_bio_noacct_nocheck+0x331/0x400\n __blkdev_direct_IO_async+0x2dd/0x330\n blkdev_write_iter+0x39a/0x450\n io_write+0x22a/0x840\n io_issue_sqe+0x87/0x300\n io_wq_submit_work+0xeb/0x390\n io_worker_handle_work+0x24d/0x550\n io_wq_worker+0x27f/0x6c0\n ret_from_fork+0x2d/0x50\n ret_from_fork_asm+0x1b/0x30\n\nFreed by task 808589:\n kasan_save_stack+0x1e/0x40\n kasan_set_track+0x21/0x30\n kasan_save_free_info+0x27/0x40\n __kasan_slab_free+0x126/0x1b0\n kmem_cache_free+0x10c/0x750\n bfq_put_queue+0x2dd/0x770\n __bfq_insert_request.isra.0+0x155/0x7a0\n bfq_insert_request.isra.0+0x122/0x480\n bfq_insert_requests+0x156/0x180\n blk_mq_dispatch_plug_list+0x528/0x7e0\n blk_mq_flush_plug_list.part.0+0xe5/0x590\n __blk_flush_plug+0x3b/0x90\n blk_finish_plug+0x40/0x60\n do_writepages+0x19d/0x310\n filemap_fdatawrite_wbc+0x95/0xc0\n __filemap_fdatawrite_range+0x99/0xd0\n filemap_write_and_wait_range.part.0+0x4d/0xa0\n blkdev_read_iter+0xef/0x1e0\n io_read+0x1b6/0x8a0\n io_issue_sqe+0x87/0x300\n io_wq_submit_work+0xeb/0x390\n io_worker_handle_work+0x24d/0x550\n io_wq_worker+0x27f/0x6c0\n ret_from_fork+0x2d/0x50\n ret_from_fork_asm+0x1b/0x30\n\nFix the problem by protecting bic_to_bfqq() with bfqd->lock.\n\n## Affected\n\n- `linux_kernel >= 5.17, < 6.6.64`\n- `linux_kernel >= 6.7, < 6.11.11`\n- `linux_kernel >= 6.12, < 6.12.2`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 6.12.2`","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}