{"id":"CVE-2024-26704","summary":"ext4: fix double-free of blocks due to wrong extents moved_len","details":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix double-free of blocks due to wrong extents moved_len\n\nIn ext4_move_extents(), moved_len is only updated when all moves are\nsuccessfully executed, and only discards orig_inode and donor_inode\npreallocations when moved_len is not zero. When the loop fails to exit\nafter successfully moving some extents, moved_len is not updated and\nremains at 0, so it does not discard the preallocations.\n\nIf the moved extents overlap with the preallocated extents, the\noverlapped extents are freed twice in ext4_mb_release_inode_pa() and\next4_process_freed_data() (as described in commit 94d7c16cbbbd (\"ext4:\nFix double-free of blocks with EXT4_IOC_MOVE_EXT\")), and bb_free is\nincremented twice. Hence when trim is executed, a zero-division bug is\ntriggered in mb_update_avg_fragment_size() because bb_free is not zero\nand bb_fragments is zero.\n\nTherefore, update move_len after each extent move to avoid the issue.","modified":"2026-04-02T10:05:35.336686Z","published":"2024-04-03T14:55:02.672Z","related":["SUSE-SU-2024:1454-1","SUSE-SU-2024:1465-1","SUSE-SU-2024:1489-1","SUSE-SU-2024:1490-1","SUSE-SU-2024:1641-1","SUSE-SU-2024:1643-1","SUSE-SU-2024:1646-1","SUSE-SU-2024:1647-1","SUSE-SU-2024:1659-1","SUSE-SU-2024:1663-1","SUSE-SU-2024:1870-1","SUSE-SU-2024:2135-1","SUSE-SU-2024:2203-1","SUSE-SU-2024:2973-1","SUSE-SU-2025:20008-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26704.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/185eab30486ba3e7bf8b9c2e049c79a06ffd2bc1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2883940b19c38d5884c8626483811acf4d7e148f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/55583e899a5357308274601364741a83e78d6ac4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/559ddacb90da1d8786dd8ec4fd76bbfa404eaef6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/afba9d11320dad5ce222ac8964caf64b7b4bedb1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/afbcad9ae7d6d11608399188f03a837451b6b3a1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b4fbb89d722cbb16beaaea234b7230faaaf68c71"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d033a555d9a1cf53dbf3301af7199cc4a4c8f537"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26704.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-26704"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"fcf6b1b729bcd23f2b49a84fb33ffbb44712ee6a"},{"fixed":"b4fbb89d722cbb16beaaea234b7230faaaf68c71"},{"fixed":"afbcad9ae7d6d11608399188f03a837451b6b3a1"},{"fixed":"d033a555d9a1cf53dbf3301af7199cc4a4c8f537"},{"fixed":"afba9d11320dad5ce222ac8964caf64b7b4bedb1"},{"fixed":"185eab30486ba3e7bf8b9c2e049c79a06ffd2bc1"},{"fixed":"2883940b19c38d5884c8626483811acf4d7e148f"},{"fixed":"559ddacb90da1d8786dd8ec4fd76bbfa404eaef6"},{"fixed":"55583e899a5357308274601364741a83e78d6ac4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-26704.json"}}],"schema_version":"1.7.5"}