{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-49882","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-10-21T12:17:06.021Z","datePublished":"2024-10-21T18:01:20.144Z","dateUpdated":"2025-11-03T22:22:48.090Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2025-05-04T09:40:17.799Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix double brelse() the buffer of the extents path\n\nIn ext4_ext_try_to_merge_up(), set path[1].p_bh to NULL after it has been\nreleased, otherwise it may be released twice. An example of what triggers\nthis is as follows:\n\n  split2    map    split1\n|--------|-------|--------|\n\next4_ext_map_blocks\n ext4_ext_handle_unwritten_extents\n  ext4_split_convert_extents\n   // path->p_depth == 0\n   ext4_split_extent\n     // 1. do split1\n     ext4_split_extent_at\n       |ext4_ext_insert_extent\n       |  ext4_ext_create_new_leaf\n       |    ext4_ext_grow_indepth\n       |      le16_add_cpu(&neh->eh_depth, 1)\n       |    ext4_find_extent\n       |      // return -ENOMEM\n       |// get error and try zeroout\n       |path = ext4_find_extent\n       |  path->p_depth = 1\n       |ext4_ext_try_to_merge\n       |  ext4_ext_try_to_merge_up\n       |    path->p_depth = 0\n       |    brelse(path[1].p_bh)  ---> not set to NULL here\n       |// zeroout success\n     // 2. update path\n     ext4_find_extent\n     // 3. do split2\n     ext4_split_extent_at\n       ext4_ext_insert_extent\n         ext4_ext_create_new_leaf\n           ext4_ext_grow_indepth\n             le16_add_cpu(&neh->eh_depth, 1)\n           ext4_find_extent\n             path[0].p_bh = NULL;\n             path->p_depth = 1\n             read_extent_tree_block  ---> return err\n             // path[1].p_bh is still the old value\n             ext4_free_ext_path\n               ext4_ext_drop_refs\n                 // path->p_depth == 1\n                 brelse(path[1].p_bh)  ---> brelse a buffer twice\n\nFinally got the following WARRNING when removing the buffer from lru:\n\n============================================\nVFS: brelse: Trying to free free buffer\nWARNING: CPU: 2 PID: 72 at fs/buffer.c:1241 __brelse+0x58/0x90\nCPU: 2 PID: 72 Comm: kworker/u19:1 Not tainted 6.9.0-dirty #716\nRIP: 0010:__brelse+0x58/0x90\nCall Trace:\n <TASK>\n __find_get_block+0x6e7/0x810\n bdev_getblk+0x2b/0x480\n __ext4_get_inode_loc+0x48a/0x1240\n ext4_get_inode_loc+0xb2/0x150\n ext4_reserve_inode_write+0xb7/0x230\n __ext4_mark_inode_dirty+0x144/0x6a0\n ext4_ext_insert_extent+0x9c8/0x3230\n ext4_ext_map_blocks+0xf45/0x2dc0\n ext4_map_blocks+0x724/0x1700\n ext4_do_writepages+0x12d6/0x2a70\n[...]\n============================================"}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/ext4/extents.c"],"versions":[{"version":"ecb94f5fdf4b72547fca022421a9dca1672bddd4","lessThan":"d4574bda63906bf69660e001470bfe1a0ac524ae","status":"affected","versionType":"git"},{"version":"ecb94f5fdf4b72547fca022421a9dca1672bddd4","lessThan":"f9fd47c9d9548f9e47fa60098eab99dde175401d","status":"affected","versionType":"git"},{"version":"ecb94f5fdf4b72547fca022421a9dca1672bddd4","lessThan":"b6c29c8f3d7cb67b505f3b2f6c242d52298d1f2e","status":"affected","versionType":"git"},{"version":"ecb94f5fdf4b72547fca022421a9dca1672bddd4","lessThan":"32bbb59e3f18facd7201bef110010bf35819b8c3","status":"affected","versionType":"git"},{"version":"ecb94f5fdf4b72547fca022421a9dca1672bddd4","lessThan":"78bbc3d15b6f443acb26e94418c445bac940d414","status":"affected","versionType":"git"},{"version":"ecb94f5fdf4b72547fca022421a9dca1672bddd4","lessThan":"68a69cf60660c73990c1875f94a5551600b04775","status":"affected","versionType":"git"},{"version":"ecb94f5fdf4b72547fca022421a9dca1672bddd4","lessThan":"7633407ca4ab8be2916ab214eb44ccebc6a50e1a","status":"affected","versionType":"git"},{"version":"ecb94f5fdf4b72547fca022421a9dca1672bddd4","lessThan":"230ee0535d01478bad9a3037292043f39b9be10b","status":"affected","versionType":"git"},{"version":"ecb94f5fdf4b72547fca022421a9dca1672bddd4","lessThan":"dcaa6c31134c0f515600111c38ed7750003e1b9c","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/ext4/extents.c"],"versions":[{"version":"3.7","status":"affected"},{"version":"0","lessThan":"3.7","status":"unaffected","versionType":"semver"},{"version":"4.19.323","lessThanOrEqual":"4.19.*","status":"unaffected","versionType":"semver"},{"version":"5.4.285","lessThanOrEqual":"5.4.*","status":"unaffected","versionType":"semver"},{"version":"5.10.227","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.168","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.113","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.55","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.10.14","lessThanOrEqual":"6.10.*","status":"unaffected","versionType":"semver"},{"version":"6.11.3","lessThanOrEqual":"6.11.*","status":"unaffected","versionType":"semver"},{"version":"6.12","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":"3.7","versionEndExcluding":"4.19.323"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"5.4.285"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"5.10.227"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"5.15.168"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.1.113"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.6.55"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.10.14"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.11.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.7","versionEndExcluding":"6.12"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/d4574bda63906bf69660e001470bfe1a0ac524ae"},{"url":"https://git.kernel.org/stable/c/f9fd47c9d9548f9e47fa60098eab99dde175401d"},{"url":"https://git.kernel.org/stable/c/b6c29c8f3d7cb67b505f3b2f6c242d52298d1f2e"},{"url":"https://git.kernel.org/stable/c/32bbb59e3f18facd7201bef110010bf35819b8c3"},{"url":"https://git.kernel.org/stable/c/78bbc3d15b6f443acb26e94418c445bac940d414"},{"url":"https://git.kernel.org/stable/c/68a69cf60660c73990c1875f94a5551600b04775"},{"url":"https://git.kernel.org/stable/c/7633407ca4ab8be2916ab214eb44ccebc6a50e1a"},{"url":"https://git.kernel.org/stable/c/230ee0535d01478bad9a3037292043f39b9be10b"},{"url":"https://git.kernel.org/stable/c/dcaa6c31134c0f515600111c38ed7750003e1b9c"}],"title":"ext4: fix double brelse() the buffer of the extents path","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2024-49882","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-10-22T13:45:30.617937Z"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-10-22T13:48:50.395Z"}},{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html"},{"url":"https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2025-11-03T22:22:48.090Z"}}]}}