{"id":"CVE-2024-26870","summary":"NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102\n\nA call to listxattr() with a buffer size = 0 returns the actual\nsize of the buffer needed for a subsequent call. When size \u003e 0,\nnfs4_listxattr() does not return an error because either\ngeneric_listxattr() or nfs4_listxattr_nfs4_label() consumes\nexactly all the bytes then size is 0 when calling\nnfs4_listxattr_nfs4_user() which then triggers the following\nkernel BUG:\n\n  [   99.403778] kernel BUG at mm/usercopy.c:102!\n  [   99.404063] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP\n  [   99.408463] CPU: 0 PID: 3310 Comm: python3 Not tainted 6.6.0-61.fc40.aarch64 #1\n  [   99.415827] Call trace:\n  [   99.415985]  usercopy_abort+0x70/0xa0\n  [   99.416227]  __check_heap_object+0x134/0x158\n  [   99.416505]  check_heap_object+0x150/0x188\n  [   99.416696]  __check_object_size.part.0+0x78/0x168\n  [   99.416886]  __check_object_size+0x28/0x40\n  [   99.417078]  listxattr+0x8c/0x120\n  [   99.417252]  path_listxattr+0x78/0xe0\n  [   99.417476]  __arm64_sys_listxattr+0x28/0x40\n  [   99.417723]  invoke_syscall+0x78/0x100\n  [   99.417929]  el0_svc_common.constprop.0+0x48/0xf0\n  [   99.418186]  do_el0_svc+0x24/0x38\n  [   99.418376]  el0_svc+0x3c/0x110\n  [   99.418554]  el0t_64_sync_handler+0x120/0x130\n  [   99.418788]  el0t_64_sync+0x194/0x198\n  [   99.418994] Code: aa0003e3 d000a3e0 91310000 97f49bdb (d4210000)\n\nIssue is reproduced when generic_listxattr() returns 'system.nfs4_acl',\nthus calling lisxattr() with size = 16 will trigger the bug.\n\nAdd check on nfs4_listxattr() to return ERANGE error when it is\ncalled with size \u003e 0 and the return value is greater than size.","modified":"2026-04-02T10:06:14.273225Z","published":"2024-04-17T10:27:30.756Z","related":["ALSA-2024:5102","SUSE-SU-2024:2008-1","SUSE-SU-2024:2019-1","SUSE-SU-2024:2135-1","SUSE-SU-2024:2190-1","SUSE-SU-2024:2203-1","SUSE-SU-2024:2973-1","SUSE-SU-2025:20008-1","SUSE-SU-2025:20028-1","SUSE-SU-2025:20166-1","SUSE-SU-2025:20249-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26870.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/06e828b3f1b206de08ef520fc46a40b22e1869cb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/23bfecb4d852751d5e403557dd500bb563313baf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/251a658bbfceafb4d58c76b77682c8bf7bcfad65"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4403438eaca6e91f02d272211c4d6b045092396b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/79cdcc765969d23f4e3d6ea115660c3333498768"},{"type":"WEB","url":"https://git.kernel.org/stable/c/80365c9f96015bbf048fdd6c8705d3f8770132bf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9d52865ff28245fc2134da9f99baff603a24407a"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26870.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-26870"},{"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":"012a211abd5db098094ce429de5f046368391e68"},{"fixed":"4403438eaca6e91f02d272211c4d6b045092396b"},{"fixed":"9d52865ff28245fc2134da9f99baff603a24407a"},{"fixed":"06e828b3f1b206de08ef520fc46a40b22e1869cb"},{"fixed":"79cdcc765969d23f4e3d6ea115660c3333498768"},{"fixed":"80365c9f96015bbf048fdd6c8705d3f8770132bf"},{"fixed":"23bfecb4d852751d5e403557dd500bb563313baf"},{"fixed":"251a658bbfceafb4d58c76b77682c8bf7bcfad65"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-26870.json"}}],"schema_version":"1.7.5"}