{"id":"DEBIAN-CVE-2024-26870","details":"In the Linux kernel, the following vulnerability has been resolved:  NFSv4.2: fix nfs4_listxattr kernel BUG at mm/usercopy.c:102  A call to listxattr() with a buffer size = 0 returns the actual size of the buffer needed for a subsequent call. When size \u003e 0, nfs4_listxattr() does not return an error because either generic_listxattr() or nfs4_listxattr_nfs4_label() consumes exactly all the bytes then size is 0 when calling nfs4_listxattr_nfs4_user() which then triggers the following kernel BUG:    [   99.403778] kernel BUG at mm/usercopy.c:102!   [   99.404063] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP   [   99.408463] CPU: 0 PID: 3310 Comm: python3 Not tainted 6.6.0-61.fc40.aarch64 #1   [   99.415827] Call trace:   [   99.415985]  usercopy_abort+0x70/0xa0   [   99.416227]  __check_heap_object+0x134/0x158   [   99.416505]  check_heap_object+0x150/0x188   [   99.416696]  __check_object_size.part.0+0x78/0x168   [   99.416886]  __check_object_size+0x28/0x40   [   99.417078]  listxattr+0x8c/0x120   [   99.417252]  path_listxattr+0x78/0xe0   [   99.417476]  __arm64_sys_listxattr+0x28/0x40   [   99.417723]  invoke_syscall+0x78/0x100   [   99.417929]  el0_svc_common.constprop.0+0x48/0xf0   [   99.418186]  do_el0_svc+0x24/0x38   [   99.418376]  el0_svc+0x3c/0x110   [   99.418554]  el0t_64_sync_handler+0x120/0x130   [   99.418788]  el0t_64_sync+0x194/0x198   [   99.418994] Code: aa0003e3 d000a3e0 91310000 97f49bdb (d4210000)  Issue is reproduced when generic_listxattr() returns 'system.nfs4_acl', thus calling lisxattr() with size = 16 will trigger the bug.  Add check on nfs4_listxattr() to return ERANGE error when it is called with size \u003e 0 and the return value is greater than size.","modified":"2026-09-15T09:03:05.690502074Z","published":"2024-04-17T11:15:09.460Z","upstream":["CVE-2024-26870"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-26870"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.85-1"}]}],"versions":["6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-26870.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.7.12-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-26870.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.7.12-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-26870.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}