{"id":"CVE-2026-97556","summary":"smb: client: avoid leaking refcount when cifs_sb_tlink() fails","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: avoid leaking refcount when cifs_sb_tlink() fails\n\ncifs_oplock_break() takes over the reference that\ncifs_queue_oplock_break() acquired when it queued the work, and drops it\nwith _cifsFileInfo_put() once the break has been processed.\n\nOnly in setups with \"-o multiuser\", cifs_sb_tlink() may fail, at which\npoint cifs_oplock_break() returns without putting the file reference,\nmirroring the reference leak we already fixed in the companion patch to\ncifs_queue_oplock_break().\n\nThis would trigger a crash due to busy inodes on the next unmount:\n\n  BUG: Dentry ... still in use (1) [unmount of cifs cifs]\n  VFS: Busy inodes after unmount of cifs (cifs)\n\nDrop the reference on that path as well. Doing so before the out label\nmirrors the normal path, which also puts the reference before\ncifs_done_oplock_break().\n\nFound by Sashiko code review. The failure path was not exercised at\nruntime.","modified":"2026-11-13T04:07:18.172075694Z","published":"2026-09-25T10:21:47.078Z","related":["SUSE-SU-2026:24386-1","SUSE-SU-2026:24422-1","SUSE-SU-2026:24437-1","SUSE-SU-2026:24446-1","SUSE-SU-2026:24550-1","SUSE-SU-2026:24619-1","openSUSE-SU-2026:12074-1","openSUSE-SU-2026:22167-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97556.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/1d1b0f1d812a4011a57bc6c70492c34a2e46c6dd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/23b26f4408ac3f35a482d2e5cf6fc865d4201b71"},{"type":"WEB","url":"https://git.kernel.org/stable/c/55c5f095d4df14271b238f826e1392fda7b6e60e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9ec991e148368e3207e98134c509a625097f7693"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dd03fd658ea59821505e0e643b6b7cbdf51c4e1d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e9c5bcc88b8337157e480c85a6d2f326bc265012"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f1fd8a84181b3af03c508e0b02b4877945dd070a"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/97xxx/CVE-2026-97556.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97556"},{"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":"b99f490ea87ebcca3a429fd8837067feb56a4c7c"},{"fixed":"f1fd8a84181b3af03c508e0b02b4877945dd070a"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5ee28bcfbaacf289eb25c662a2862542ea6ce6a7"},{"fixed":"55c5f095d4df14271b238f826e1392fda7b6e60e"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"e8f5f849ffce24490eb9449e98312b66c0dba76f"},{"fixed":"e9c5bcc88b8337157e480c85a6d2f326bc265012"},{"fixed":"9ec991e148368e3207e98134c509a625097f7693"},{"fixed":"dd03fd658ea59821505e0e643b6b7cbdf51c4e1d"},{"fixed":"1d1b0f1d812a4011a57bc6c70492c34a2e46c6dd"},{"fixed":"23b26f4408ac3f35a482d2e5cf6fc865d4201b71"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6b67a6d2e50634fe127e656147c81915955e9f5e"}]}],"versions":["v5.15.223","v5.15.222","v5.15.221","v5.15.220","v5.15.219","v5.15.218","v5.15.217","v5.15.216","v5.15.215","v5.15.214","v5.15.213","v5.15.212","v5.15.211","v5.15.210","v5.15.209","v5.15.208","v5.15.207","v5.15.206","v5.15.205","v5.15.204","v5.15.203","v5.15.202","v5.15.201","v5.15.200","v5.15.199","v5.15.198","v5.15.197","v5.15.196","v5.15.195","v5.15.194","v5.15.193","v5.15.192","v5.15.191","v5.15.190","v5.15.189","v5.15.188","v5.15.187","v5.15.186","v5.15.185","v5.15.184","v5.15.183","v5.15.182","v5.15.181","v5.15.180","v5.15.179","v5.15.178","v5.15.177","v5.15.176","v5.15.175","v5.15.174","v5.15.173","v5.15.172","v5.15.171","v5.15.170","v5.15.169","v5.15.168","v5.15.167","v5.15.166","v5.15.165","v5.15.164","v5.15.163","v5.15.162","v5.15.161","v5.15.160","v5.15.159","v5.15.158","v5.15.157","v5.15.156","v5.15.155","v5.15.154","v5.15.153","v5.15.152","v5.15.151","v5.15.150","v5.15.149","v5.15.148","v5.15.147","v5.15.146","v5.15.145","v5.15.144","v5.15.143","v5.15.142","v5.15.141","v5.15.140","v5.15.139","v5.15.138","v5.15.137","v5.15.136","v5.15.135","v5.15.134","v5.15.133","v5.15.132","v5.15.131","v5.15.130","v5.15.129","v5.15.128","v6.1.188","v6.1.187","v6.1.186","v6.1.185","v6.1.184","v6.1.183","v6.1.182","v6.1.181","v6.1.180","v6.1.179","v6.1.178","v6.1.177","v6.1.176","v6.1.175","v6.1.174","v6.1.173","v6.1.172","v6.1.171","v6.1.170","v6.1.169","v6.1.168","v6.1.167","v6.1.166","v6.1.165","v6.1.164","v6.1.163","v6.1.162","v6.1.161","v6.1.160","v6.1.159","v6.1.158","v6.1.157","v6.1.156","v6.1.155","v6.1.154","v6.1.153","v6.1.152","v6.1.151","v6.1.150","v6.1.149","v6.1.148","v6.1.147","v6.1.146","v6.1.145","v6.1.144","v6.1.143","v6.1.142","v6.1.141","v6.1.140","v6.1.139","v6.1.138","v6.1.137","v6.1.136","v6.1.135","v6.1.134","v6.1.133","v6.1.132","v6.1.131","v6.1.130","v6.1.129","v6.1.128","v6.1.127","v6.1.126","v6.1.125","v6.1.124","v6.1.123","v6.1.122","v6.1.121","v6.1.120","v6.1.119","v6.1.118","v6.1.117","v6.1.116","v6.1.115","v6.1.114","v6.1.113","v6.1.112","v6.1.111","v6.1.110","v6.1.109","v6.1.108","v6.1.107","v6.1.106","v6.1.105","v6.1.104","v6.1.103","v6.1.102","v6.1.101","v6.1.100","v6.1.99","v6.1.98","v6.1.97","v6.1.96","v6.1.95","v6.1.94","v6.1.93","v6.1.92","v6.1.91","v6.1.90","v6.1.89","v6.1.88","v6.1.87","v6.1.86","v6.1.85","v6.1.84","v6.1.83","v6.1.82","v6.1.81","v6.1.80","v6.1.79","v6.1.78","v6.1.77","v6.1.76","v6.1.75","v6.1.74","v6.1.73","v6.1.72","v6.1.71","v6.1.70","v6.1.69","v6.1.68","v6.1.67","v6.1.66","v6.1.65","v6.1.64","v6.1.63","v6.1.62","v6.1.61","v6.1.60","v6.1.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