{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-53537", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-10-04T15:14:15.919Z", "datePublished": "2025-10-04T15:16:48.006Z", "dateUpdated": "2026-08-05T09:14:41.501Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:14:41.501Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to avoid use-after-free for cached IPU bio\n\nxfstest generic/019 reports a bug:\n\nkernel BUG at mm/filemap.c:1619!\nRIP: 0010:folio_end_writeback+0x8a/0x90\nCall Trace:\n end_page_writeback+0x1c/0x60\n f2fs_write_end_io+0x199/0x420\n bio_endio+0x104/0x180\n submit_bio_noacct+0xa5/0x510\n submit_bio+0x48/0x80\n f2fs_submit_write_bio+0x35/0x300\n f2fs_submit_merged_ipu_write+0x2a0/0x2b0\n f2fs_write_single_data_page+0x838/0x8b0\n f2fs_write_cache_pages+0x379/0xa30\n f2fs_write_data_pages+0x30c/0x340\n do_writepages+0xd8/0x1b0\n __writeback_single_inode+0x44/0x370\n writeback_sb_inodes+0x233/0x4d0\n __writeback_inodes_wb+0x56/0xf0\n wb_writeback+0x1dd/0x2d0\n wb_workfn+0x367/0x4a0\n process_one_work+0x21d/0x430\n worker_thread+0x4e/0x3c0\n kthread+0x103/0x130\n ret_from_fork+0x2c/0x50\n\nThe root cause is: after cp_error is set, f2fs_submit_merged_ipu_write()\nin f2fs_write_single_data_page() tries to flush IPU bio in cache, however\nf2fs_submit_merged_ipu_write() missed to check validity of @bio parameter,\nresult in submitting random cached bio which belong to other IO context,\nthen it will cause use-after-free issue, fix it by adding additional\nvalidity check." } ], "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 f2fs data writeback path, reached through ordinary local filesystem activity (write/fsync/msync on an f2fs mount, plus the kernel flusher and reclaim threads); no network protocol data is involved.\nAC:L - Once the filesystem is in the cp_error state, the defect is essentially deterministic rather than a race — the stale bio_entry left behind by f2fs_inplace_write_data()'s drop_bio path is picked up by the very next unguarded f2fs_submit_merged_ipu_write() call, which is how a stock xfstest (generic/019) reproduces it; the attacker fully controls the dirty-page/IPU workload on both sides of the cross-thread variant by spawning concurrent writers with small fsync batches.\nPR:L - Any unprivileged local user or Android app with write access to an f2fs mount can drive the IPU writeback path; there is no capability check anywhere between write()/fsync() and f2fs_submit_merged_ipu_write().\nUI:N - The flush is performed by the kernel's own writeback/reclaim kworkers and by the attacker's own file writes; no victim action is required.\nS:U - The corrupted struct bio, page-writeback state, and sbi page counters all live within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The bio is submitted and completed twice and its refcount driven to zero while other contexts still hold the pointer, giving a use-after-free on a bioset slab object whose bi_private/bi_end_io/bi_io_vec are dereferenced afterwards — a freed-object read primitive that leaks kernel data once the slot is reclaimed by attacker-sprayed content.\nI:H - Re-submitting a freed/completed bio makes the block layer act on attacker-groomable heap contents (bi_end_io is called as a function pointer, bio_vec entries are DMA'd to disk), and the cross-context steal lets add_ipu_page()/bio_add_page() write into a bio after it was freed — a controllable write and control-flow hijack primitive.\nA:H - The confirmed immediate effect is a kernel BUG_ON panic in folio_end_writeback() (mm/filemap.c:1619) from double end_page_writeback(); the duplicated dec_page_count() also underflows the writeback counters, which hangs sync/umount waiters forever." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/f2fs/data.c" ], "versions": [ { "version": "0b20fcec8651569935a10afe03fedc0b812d044e", "lessThan": "b2f423fda64fb49213aa0ed5056079cf295a5df2", "status": "affected", "versionType": "git" }, { "version": "0b20fcec8651569935a10afe03fedc0b812d044e", "lessThan": "9a7f63283af6befc0f91d549f4f6917dff7479a9", "status": "affected", "versionType": "git" }, { "version": "0b20fcec8651569935a10afe03fedc0b812d044e", "lessThan": "7d058f0ab161437369ad6e45a4b67c2886e71373", "status": "affected", "versionType": "git" }, { "version": "0b20fcec8651569935a10afe03fedc0b812d044e", "lessThan": "97ec6f1788cc6bee3f8c89cb908e1a2a1cd859bb", "status": "affected", "versionType": "git" }, { "version": "0b20fcec8651569935a10afe03fedc0b812d044e", "lessThan": "af4ce124d7bd74cb839bbdaccffbb416771a56b5", "status": "affected", "versionType": "git" }, { "version": "0b20fcec8651569935a10afe03fedc0b812d044e", "lessThan": "5cdb422c839134273866208dad5360835ddb9794", "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/f2fs/data.c" ], "versions": [ { "version": "5.5", "status": "affected" }, { "version": "0", "lessThan": "5.5", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.180", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.111", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.28", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.2.15", "lessThanOrEqual": "6.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.3.2", "lessThanOrEqual": "6.3.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.4", "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": "5.5", "versionEndExcluding": "5.10.180" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.15.111" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.1.28" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.2.15" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.3.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.4" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/b2f423fda64fb49213aa0ed5056079cf295a5df2" }, { "url": "https://git.kernel.org/stable/c/9a7f63283af6befc0f91d549f4f6917dff7479a9" }, { "url": "https://git.kernel.org/stable/c/7d058f0ab161437369ad6e45a4b67c2886e71373" }, { "url": "https://git.kernel.org/stable/c/97ec6f1788cc6bee3f8c89cb908e1a2a1cd859bb" }, { "url": "https://git.kernel.org/stable/c/af4ce124d7bd74cb839bbdaccffbb416771a56b5" }, { "url": "https://git.kernel.org/stable/c/5cdb422c839134273866208dad5360835ddb9794" } ], "title": "f2fs: fix to avoid use-after-free for cached IPU bio", "x_generator": { "engine": "bippy-1.2.0" } } } }