{"id":"CVE-2026-64141","summary":"ksmbd: fix null pointer dereference in compare_guid_key()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix null pointer dereference in compare_guid_key()\n\nsession_fd_check() walks the per-inode m_op_list during durable-handle\nsession teardown and sets op-\u003econn = NULL for every opinfo whose conn\nmatched the closing session's connection. The matching opinfo, however,\nstays linked in its per-ClientGuid lease_table_list entry's lb-\u003elease_list\nbecause destroy_lease_table() only runs on full TCP-connection teardown,\nnot on SESSION_LOGOFF.\n\nIf the same TCP connection then negotiates a fresh session with the\nsame ClientGuid (ClientGuid is bound to NEGOTIATE, not the session, and\nis unchanged across LOGOFF + SETUP) and issues a SMB2 CREATE with a\nlease context on a different inode, find_same_lease_key() walks\nlb-\u003elease_list, reaches the stale opinfo, and calls compare_guid_key(),\nwhich unconditionally dereferences opinfo-\u003econn-\u003eClientGUID. The conn\npointer is NULL and the kernel panics.\n\nReproducer requires only a successful SMB2 SESSION_SETUP and a share\nconfigured with 'durable handles = yes'. KASAN report on mainline\n70390501d194:\n\n  general protection fault, probably for non-canonical address\n  0xdffffc0000000069: 0000 [#1] SMP KASAN PTI\n  KASAN: null-ptr-deref in range [0x0000000000000348-0x000000000000034f]\n  Workqueue: ksmbd-io handle_ksmbd_work\n  RIP: 0010:bcmp+0x5b/0x230\n  Call Trace:\n   compare_guid_key+0x4b/0xd0\n   find_same_lease_key+0x324/0x690\n   smb2_open+0x6aea/0x8e60\n   handle_ksmbd_work+0x796/0xee0\n   ...\n\nFaulting address 0x348 is the offset of ClientGUID within struct\nksmbd_conn, confirming opinfo-\u003econn was NULL.\n\nRead opinfo-\u003econn once and bail out if it has been cleared by a\nconcurrent session_fd_check(). A half-detached opinfo cannot be the\nowner of an active lease, so returning 0 is the correct match result.","modified":"2026-08-12T03:51:28.094310105Z","published":"2026-07-19T15:40:33.890Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64141.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0836081b394ca074d1b910f2b990ff7b4b4404c7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4b83cbc4c15f09b000cc06f033f64b0824b6dc87"},{"type":"WEB","url":"https://git.kernel.org/stable/c/af86896ca3239e25a6bd7d352213371265073d38"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cd5c1b75d2f454f625d7dc55bd3ae21d0855f6ad"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e43cb36d4d7827710cfcd48e95e29a507f0d87be"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64141.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64141"},{"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":"8df4bcdb0a4232192b2445256c39b787d58ef14d"},{"fixed":"e43cb36d4d7827710cfcd48e95e29a507f0d87be"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"c8efcc786146a951091588e5fa7e3c754850cb3c"},{"fixed":"0836081b394ca074d1b910f2b990ff7b4b4404c7"},{"fixed":"cd5c1b75d2f454f625d7dc55bd3ae21d0855f6ad"},{"fixed":"af86896ca3239e25a6bd7d352213371265073d38"},{"fixed":"4b83cbc4c15f09b000cc06f033f64b0824b6dc87"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6.6.32"},{"fixed":"6.6.142"}]}],"versions":["v6.6.141","v6.6.140","v6.6.139","v6.6.138","v6.6.137","v6.6.136","v6.6.135","v6.6.134","v6.6.133","v6.6.132","v6.6.131","v6.6.130","v6.6.129","v6.6.128","v6.6.127","v6.6.126","v6.6.125","v6.6.124","v6.6.123","v6.6.122","v6.6.121","v6.6.120","v6.6.119","v6.6.118","v6.6.117","v6.6.116","v6.6.115","v6.6.114","v6.6.113","v6.6.112","v6.6.111","v6.6.110","v6.6.109","v6.6.108","v6.6.107","v6.6.106","v6.6.105","v6.6.104","v6.6.103","v6.6.102","v6.6.101","v6.6.100","v6.6.99","v6.6.98","v6.6.97","v6.6.96","v6.6.95","v6.6.94","v6.6.93","v6.6.92","v6.6.91","v6.6.90","v6.6.89","v6.6.88","v6.6.87","v6.6.86","v6.6.85","v6.6.84","v6.6.83","v6.6.82","v6.6.81","v6.6.80","v6.6.79","v6.6.78","v6.6.77","v6.6.76","v6.6.75","v6.6.74","v6.6.73","v6.6.72","v6.6.71","v6.6.70","v6.6.69","v6.6.68","v6.6.67","v6.6.66","v6.6.65","v6.6.64","v6.6.63","v6.6.62","v6.6.61","v6.6.60","v6.6.59","v6.6.58","v6.6.57","v6.6.56","v6.6.55","v6.6.54","v6.6.53","v6.6.52","v6.6.51","v6.6.50","v6.6.49","v6.6.48","v6.6.47","v6.6.46","v6.6.45","v6.6.44","v6.6.43","v6.6.42","v6.6.41","v6.6.40","v6.6.39","v6.6.38","v6.6.37","v6.6.36","v6.6.35","v6.6.34","v6.6.33","v6.6.32"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64141.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.142"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.92"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.9.0"},{"fixed":"6.18.34"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"7.0.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64141.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}