{"id":"CVE-2024-49883","summary":"ext4: aovid use-after-free in ext4_ext_insert_extent()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\next4: aovid use-after-free in ext4_ext_insert_extent()\n\nAs Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is\nreallocated in ext4_ext_create_new_leaf(), we'll use the stale path and\ncause UAF. Below is a sample trace with dummy values:\n\next4_ext_insert_extent\n  path = *ppath = 2000\n  ext4_ext_create_new_leaf(ppath)\n    ext4_find_extent(ppath)\n      path = *ppath = 2000\n      if (depth \u003e path[0].p_maxdepth)\n            kfree(path = 2000);\n            *ppath = path = NULL;\n      path = kcalloc() = 3000\n      *ppath = 3000;\n      return path;\n  /* here path is still 2000, UAF! */\n  eh = path[depth].p_hdr\n\n==================================================================\nBUG: KASAN: slab-use-after-free in ext4_ext_insert_extent+0x26d4/0x3330\nRead of size 8 at addr ffff8881027bf7d0 by task kworker/u36:1/179\nCPU: 3 UID: 0 PID: 179 Comm: kworker/u6:1 Not tainted 6.11.0-rc2-dirty #866\nCall Trace:\n \u003cTASK\u003e\n ext4_ext_insert_extent+0x26d4/0x3330\n ext4_ext_map_blocks+0xe22/0x2d40\n ext4_map_blocks+0x71e/0x1700\n ext4_do_writepages+0x1290/0x2800\n[...]\n\nAllocated by task 179:\n ext4_find_extent+0x81c/0x1f70\n ext4_ext_map_blocks+0x146/0x2d40\n ext4_map_blocks+0x71e/0x1700\n ext4_do_writepages+0x1290/0x2800\n ext4_writepages+0x26d/0x4e0\n do_writepages+0x175/0x700\n[...]\n\nFreed by task 179:\n kfree+0xcb/0x240\n ext4_find_extent+0x7c0/0x1f70\n ext4_ext_insert_extent+0xa26/0x3330\n ext4_ext_map_blocks+0xe22/0x2d40\n ext4_map_blocks+0x71e/0x1700\n ext4_do_writepages+0x1290/0x2800\n ext4_writepages+0x26d/0x4e0\n do_writepages+0x175/0x700\n[...]\n==================================================================\n\nSo use *ppath to update the path to avoid the above problem.","modified":"2026-04-16T04:40:25.818205428Z","published":"2024-10-21T18:01:20.827Z","related":["SUSE-SU-2024:3983-1","SUSE-SU-2024:3984-1","SUSE-SU-2024:3985-1","SUSE-SU-2024:4100-1","SUSE-SU-2024:4314-1","SUSE-SU-2024:4318-1","SUSE-SU-2024:4364-1","SUSE-SU-2024:4387-1","SUSE-SU-2025:0034-1","SUSE-SU-2025:20163-1","SUSE-SU-2025:20164-1","SUSE-SU-2025:20246-1","SUSE-SU-2025:20247-1","USN-7276-1","USN-7277-1","openSUSE-SU-2024:14500-1","openSUSE-SU-2025:14705-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/49xxx/CVE-2024-49883.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/51db04892a993cace63415be99848970a0f15ef2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5e811066c5ab709b070659197dccfb80ab650ddd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8162ee5d94b8c0351be0a9321be134872a7654a1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/975ca06f3fd154c5f7742083e7b2574c57d1c0c3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9df59009dfc6d9fc1bd9ddf6c5ab6e56d6ed887a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a164f3a432aae62ca23d03e6d926b122ee5b860d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/beb7b66fb489041c50c6473100b383f7a51648fc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bfed082ce4b1ce6349b05c09a0fa4f3da35ecb1b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e17ebe4fdd7665c93ae9459ba40fcdfb76769ac1"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/49xxx/CVE-2024-49883.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-49883"},{"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":"10809df84a4d868db61af621bae3658494165279"},{"fixed":"e17ebe4fdd7665c93ae9459ba40fcdfb76769ac1"},{"fixed":"975ca06f3fd154c5f7742083e7b2574c57d1c0c3"},{"fixed":"5e811066c5ab709b070659197dccfb80ab650ddd"},{"fixed":"9df59009dfc6d9fc1bd9ddf6c5ab6e56d6ed887a"},{"fixed":"51db04892a993cace63415be99848970a0f15ef2"},{"fixed":"8162ee5d94b8c0351be0a9321be134872a7654a1"},{"fixed":"beb7b66fb489041c50c6473100b383f7a51648fc"},{"fixed":"bfed082ce4b1ce6349b05c09a0fa4f3da35ecb1b"},{"fixed":"a164f3a432aae62ca23d03e6d926b122ee5b860d"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-49883.json"}}],"schema_version":"1.7.5"}