{"id":"CVE-2023-53317","state":"PUBLISHED","title":"ext4: fix WARNING in mb_find_extent","description":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix WARNING in mb_find_extent\n\nSyzbot found the following issue:\n\nEXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\nEXT4-fs (loop0): orphan cleanup on readonly fs\n------------[ cut here ]------------\nWARNING: CPU: 1 PID: 5067 at fs/ext4/mballoc.c:1869 mb_find_extent+0x8a1/0xe30\nModules linked in:\nCPU: 1 PID: 5067 Comm: syz-executor307 Not tainted 6.2.0-rc1-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022\nRIP: 0010:mb_find_extent+0x8a1/0xe30 fs/ext4/mballoc.c:1869\nRSP: 0018:ffffc90003c9e098 EFLAGS: 00010293\nRAX: ffffffff82405731 RBX: 0000000000000041 RCX: ffff8880783457c0\nRDX: 0000000000000000 RSI: 0000000000000041 RDI: 0000000000000040\nRBP: 0000000000000040 R08: ffffffff82405723 R09: ffffed10053c9402\nR10: ffffed10053c9402 R11: 1ffff110053c9401 R12: 0000000000000000\nR13: ffffc90003c9e538 R14: dffffc0000000000 R15: ffffc90003c9e2cc\nFS:  0000555556665300(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 000056312f6796f8 CR3: 0000000022437000 CR4: 00000000003506e0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n <TASK>\n ext4_mb_complex_scan_group+0x353/0x1100 fs/ext4/mballoc.c:2307\n ext4_mb_regular_allocator+0x1533/0x3860 fs/ext4/mballoc.c:2735\n ext4_mb_new_blocks+0xddf/0x3db0 fs/ext4/mballoc.c:5605\n ext4_ext_map_blocks+0x1868/0x6880 fs/ext4/extents.c:4286\n ext4_map_blocks+0xa49/0x1cc0 fs/ext4/inode.c:651\n ext4_getblk+0x1b9/0x770 fs/ext4/inode.c:864\n ext4_bread+0x2a/0x170 fs/ext4/inode.c:920\n ext4_quota_write+0x225/0x570 fs/ext4/super.c:7105\n write_blk fs/quota/quota_tree.c:64 [inline]\n get_free_dqblk+0x34a/0x6d0 fs/quota/quota_tree.c:130\n do_insert_tree+0x26b/0x1aa0 fs/quota/quota_tree.c:340\n do_insert_tree+0x722/0x1aa0 fs/quota/quota_tree.c:375\n do_insert_tree+0x722/0x1aa0 fs/quota/quota_tree.c:375\n do_insert_tree+0x722/0x1aa0 fs/quota/quota_tree.c:375\n dq_insert_tree fs/quota/quota_tree.c:401 [inline]\n qtree_write_dquot+0x3b6/0x530 fs/quota/quota_tree.c:420\n v2_write_dquot+0x11b/0x190 fs/quota/quota_v2.c:358\n dquot_acquire+0x348/0x670 fs/quota/dquot.c:444\n ext4_acquire_dquot+0x2dc/0x400 fs/ext4/super.c:6740\n dqget+0x999/0xdc0 fs/quota/dquot.c:914\n __dquot_initialize+0x3d0/0xcf0 fs/quota/dquot.c:1492\n ext4_process_orphan+0x57/0x2d0 fs/ext4/orphan.c:329\n ext4_orphan_cleanup+0xb60/0x1340 fs/ext4/orphan.c:474\n __ext4_fill_super fs/ext4/super.c:5516 [inline]\n ext4_fill_super+0x81cd/0x8700 fs/ext4/super.c:5644\n get_tree_bdev+0x400/0x620 fs/super.c:1282\n vfs_get_tree+0x88/0x270 fs/super.c:1489\n do_new_mount+0x289/0xad0 fs/namespace.c:3145\n do_mount fs/namespace.c:3488 [inline]\n __do_sys_mount fs/namespace.c:3697 [inline]\n __se_sys_mount+0x2d3/0x3c0 fs/namespace.c:3674\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nAdd some debug information:\nmb_find_extent: mb_find_extent block=41, order=0 needed=64 next=0 ex=0/41/1@3735929054 64 64 7\nblock_bitmap: ff 3f 0c 00 fc 01 00 00 d2 3d 00 00 00 00 00 00 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n\nAcctually, blocks per group is 64, but block bitmap indicate at least has\n128 blocks. Now, ext4_validate_block_bitmap() didn't check invalid block's\nbitmap if set.\nTo resolve above issue, add check like fsck \"Padding at end of block bitmap is\nnot set\".","publishedAt":"2025-09-16T16:11:53.877Z","updatedAt":"2026-05-11T19:42:36.536Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"775b00ba23f6f916fe2ac60c5ff7fd0fe4f28d0d","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"1b90fbc7590124c57a2e590de7fd07eba26606f1","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"5d356d902e9d5b1aaaaf2326d365340fa8a90c1b","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"d55e76e11592a1d18a179c7fd34ca1b52632beb3","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"dba62fa84a8eac44a53a2862de8a40e5bdfa0ae3","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"e4d503c956a744cb59e509ca5f134cfad423c7a3","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"dd45e536f47a82e0a405f9a4b6c7ceb367171ee9","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"fa08a7b61dff8a4df11ff1e84abfc214b487caf7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ext4/balloc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.25","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.25","versionType":"semver"},{"version":"4.19.283","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.243","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.180","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.112","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.29","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.2.16","status":"unaffected","lessThanOrEqual":"6.2.*","versionType":"semver"},{"version":"6.3.3","status":"unaffected","lessThanOrEqual":"6.3.*","versionType":"semver"},{"version":"6.4","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ext4/balloc.c"]}],"references":["https://git.kernel.org/stable/c/775b00ba23f6f916fe2ac60c5ff7fd0fe4f28d0d","https://git.kernel.org/stable/c/1b90fbc7590124c57a2e590de7fd07eba26606f1","https://git.kernel.org/stable/c/5d356d902e9d5b1aaaaf2326d365340fa8a90c1b","https://git.kernel.org/stable/c/d55e76e11592a1d18a179c7fd34ca1b52632beb3","https://git.kernel.org/stable/c/dba62fa84a8eac44a53a2862de8a40e5bdfa0ae3","https://git.kernel.org/stable/c/e4d503c956a744cb59e509ca5f134cfad423c7a3","https://git.kernel.org/stable/c/dd45e536f47a82e0a405f9a4b6c7ceb367171ee9","https://git.kernel.org/stable/c/fa08a7b61dff8a4df11ff1e84abfc214b487caf7"],"weaknesses":[],"ingestedAt":"2026-10-29T20:06:33.064Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/53xxx/CVE-2023-53317.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2023-53317","state":"PUBLISHED","datePublished":"2025-09-16T16:11:53.877Z","dateUpdated":"2026-05-11T19:42:36.536Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-09-16T16:08:59.563Z"},"containers":{"cna":{"title":"ext4: fix WARNING in mb_find_extent","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix WARNING in mb_find_extent\n\nSyzbot found the following issue:\n\nEXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\nEXT4-fs (loop0): orphan cleanup on readonly fs\n------------[ cut here ]------------\nWARNING: CPU: 1 PID: 5067 at fs/ext4/mballoc.c:1869 mb_find_extent+0x8a1/0xe30\nModules linked in:\nCPU: 1 PID: 5067 Comm: syz-executor307 Not tainted 6.2.0-rc1-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022\nRIP: 0010:mb_find_extent+0x8a1/0xe30 fs/ext4/mballoc.c:1869\nRSP: 0018:ffffc90003c9e098 EFLAGS: 00010293\nRAX: ffffffff82405731 RBX: 0000000000000041 RCX: ffff8880783457c0\nRDX: 0000000000000000 RSI: 0000000000000041 RDI: 0000000000000040\nRBP: 0000000000000040 R08: ffffffff82405723 R09: ffffed10053c9402\nR10: ffffed10053c9402 R11: 1ffff110053c9401 R12: 0000000000000000\nR13: ffffc90003c9e538 R14: dffffc0000000000 R15: ffffc90003c9e2cc\nFS:  0000555556665300(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 000056312f6796f8 CR3: 0000000022437000 CR4: 00000000003506e0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n <TASK>\n ext4_mb_complex_scan_group+0x353/0x1100 fs/ext4/mballoc.c:2307\n ext4_mb_regular_allocator+0x1533/0x3860 fs/ext4/mballoc.c:2735\n ext4_mb_new_blocks+0xddf/0x3db0 fs/ext4/mballoc.c:5605\n ext4_ext_map_blocks+0x1868/0x6880 fs/ext4/extents.c:4286\n ext4_map_blocks+0xa49/0x1cc0 fs/ext4/inode.c:651\n ext4_getblk+0x1b9/0x770 fs/ext4/inode.c:864\n ext4_bread+0x2a/0x170 fs/ext4/inode.c:920\n ext4_quota_write+0x225/0x570 fs/ext4/super.c:7105\n write_blk fs/quota/quota_tree.c:64 [inline]\n get_free_dqblk+0x34a/0x6d0 fs/quota/quota_tree.c:130\n do_insert_tree+0x26b/0x1aa0 fs/quota/quota_tree.c:340\n do_insert_tree+0x722/0x1aa0 fs/quota/quota_tree.c:375\n do_insert_tree+0x722/0x1aa0 fs/quota/quota_tree.c:375\n do_insert_tree+0x722/0x1aa0 fs/quota/quota_tree.c:375\n dq_insert_tree fs/quota/quota_tree.c:401 [inline]\n qtree_write_dquot+0x3b6/0x530 fs/quota/quota_tree.c:420\n v2_write_dquot+0x11b/0x190 fs/quota/quota_v2.c:358\n dquot_acquire+0x348/0x670 fs/quota/dquot.c:444\n ext4_acquire_dquot+0x2dc/0x400 fs/ext4/super.c:6740\n dqget+0x999/0xdc0 fs/quota/dquot.c:914\n __dquot_initialize+0x3d0/0xcf0 fs/quota/dquot.c:1492\n ext4_process_orphan+0x57/0x2d0 fs/ext4/orphan.c:329\n ext4_orphan_cleanup+0xb60/0x1340 fs/ext4/orphan.c:474\n __ext4_fill_super fs/ext4/super.c:5516 [inline]\n ext4_fill_super+0x81cd/0x8700 fs/ext4/super.c:5644\n get_tree_bdev+0x400/0x620 fs/super.c:1282\n vfs_get_tree+0x88/0x270 fs/super.c:1489\n do_new_mount+0x289/0xad0 fs/namespace.c:3145\n do_mount fs/namespace.c:3488 [inline]\n __do_sys_mount fs/namespace.c:3697 [inline]\n __se_sys_mount+0x2d3/0x3c0 fs/namespace.c:3674\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nAdd some debug information:\nmb_find_extent: mb_find_extent block=41, order=0 needed=64 next=0 ex=0/41/1@3735929054 64 64 7\nblock_bitmap: ff 3f 0c 00 fc 01 00 00 d2 3d 00 00 00 00 00 00 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff\n\nAcctually, blocks per group is 64, but block bitmap indicate at least has\n128 blocks. Now, ext4_validate_block_bitmap() didn't check invalid block's\nbitmap if set.\nTo resolve above issue, add check like fsck \"Padding at end of block bitmap is\nnot set\"."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"775b00ba23f6f916fe2ac60c5ff7fd0fe4f28d0d","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"1b90fbc7590124c57a2e590de7fd07eba26606f1","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"5d356d902e9d5b1aaaaf2326d365340fa8a90c1b","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"d55e76e11592a1d18a179c7fd34ca1b52632beb3","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"dba62fa84a8eac44a53a2862de8a40e5bdfa0ae3","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"e4d503c956a744cb59e509ca5f134cfad423c7a3","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"dd45e536f47a82e0a405f9a4b6c7ceb367171ee9","versionType":"git"},{"version":"abcb2947c91130426539f209f7a473a67a1f6663","status":"affected","lessThan":"fa08a7b61dff8a4df11ff1e84abfc214b487caf7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ext4/balloc.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.25","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.25","versionType":"semver"},{"version":"4.19.283","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.243","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.180","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.112","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.29","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.2.16","status":"unaffected","lessThanOrEqual":"6.2.*","versionType":"semver"},{"version":"6.3.3","status":"unaffected","lessThanOrEqual":"6.3.*","versionType":"semver"},{"version":"6.4","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ext4/balloc.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/775b00ba23f6f916fe2ac60c5ff7fd0fe4f28d0d"},{"url":"https://git.kernel.org/stable/c/1b90fbc7590124c57a2e590de7fd07eba26606f1"},{"url":"https://git.kernel.org/stable/c/5d356d902e9d5b1aaaaf2326d365340fa8a90c1b"},{"url":"https://git.kernel.org/stable/c/d55e76e11592a1d18a179c7fd34ca1b52632beb3"},{"url":"https://git.kernel.org/stable/c/dba62fa84a8eac44a53a2862de8a40e5bdfa0ae3"},{"url":"https://git.kernel.org/stable/c/e4d503c956a744cb59e509ca5f134cfad423c7a3"},{"url":"https://git.kernel.org/stable/c/dd45e536f47a82e0a405f9a4b6c7ceb367171ee9"},{"url":"https://git.kernel.org/stable/c/fa08a7b61dff8a4df11ff1e84abfc214b487caf7"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T19:42:36.536Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"4.19.283"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"5.4.243"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"5.10.180"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"5.15.112"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.1.29"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.2.16"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.3.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.4"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","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-2023-53317","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-01-14T18:26:23.171880Z"}}}],"problemTypes":[{"descriptions":[{"lang":"en","type":"CWE","description":"CWE-noinfo Not enough information"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-01-14T18:32:57.980Z"}}]}}}