{"id":"CVE-2026-90155","state":"PUBLISHED","title":"ksmbd: detach blocked lock requests before freeing","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: detach blocked lock requests before freeing\n\nA file_lock retained by ksmbd for byte-range lock bookkeeping can still\nbe part of the VFS blocked-request graph. In particular, the VFS can\nchain a new waiter below an already blocked request through\nflc_blocked_requests. The ksmbd_file reference count does not cover that\ngraph.\n\nBoth __ksmbd_close_fd() and the cross-request unlock path free these\nretained file_lock objects directly. If a dependent waiter is still\nattached, locks_release_private() hits\nBUG_ON(!list_empty(&flc->flc_blocked_requests)). The same lifetime\nmismatch can leave a freed ksmbd_lock reachable through its request-local\nllist.\n\nDetach the file_lock from the blocked-request graph before freeing it in\nthe close, cross-request unlock, and rollback paths. locks_delete_block()\nalso wakes requests chained below the object. Remove llist when a\ncompleted lock is published so a globally visible ksmbd_lock no longer\npoints into the submitting worker's stack.","publishedAt":"2026-09-17T16:06:47.716Z","updatedAt":"2026-10-30T12:34:28.100Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"4e8b69c06bd6583ec11abef4fae50c2c8d5f3679","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"d20d3f6ad8b0b6f4e1bb32cdf7eca251962e8f04","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"d31db79cfaa9fce6649772ad279779473ba8aef9","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"f77d2accafca529e0ea3f979eb6e6cf1dac05c90","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"514a0b2bc949963497e66cacd433f65dc768a71d","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"215e8816b1ac25176d911abb8704390413ccee4b","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/smb2pdu.c","fs/smb/server/vfs_cache.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.15","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/smb2pdu.c","fs/smb/server/vfs_cache.c"]}],"references":["https://git.kernel.org/stable/c/4e8b69c06bd6583ec11abef4fae50c2c8d5f3679","https://git.kernel.org/stable/c/d20d3f6ad8b0b6f4e1bb32cdf7eca251962e8f04","https://git.kernel.org/stable/c/d31db79cfaa9fce6649772ad279779473ba8aef9","https://git.kernel.org/stable/c/f77d2accafca529e0ea3f979eb6e6cf1dac05c90","https://git.kernel.org/stable/c/514a0b2bc949963497e66cacd433f65dc768a71d","https://git.kernel.org/stable/c/215e8816b1ac25176d911abb8704390413ccee4b"],"weaknesses":[],"ingestedAt":"2026-10-30T12:54:04.478Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/90xxx/CVE-2026-90155.json","commit":"1f312381e38164a43607eebab851b151dd16861e","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90155","state":"PUBLISHED","datePublished":"2026-09-17T16:06:47.716Z","dateUpdated":"2026-10-30T12:34:28.100Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.790Z"},"containers":{"cna":{"title":"ksmbd: detach blocked lock requests before freeing","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: detach blocked lock requests before freeing\n\nA file_lock retained by ksmbd for byte-range lock bookkeeping can still\nbe part of the VFS blocked-request graph. In particular, the VFS can\nchain a new waiter below an already blocked request through\nflc_blocked_requests. The ksmbd_file reference count does not cover that\ngraph.\n\nBoth __ksmbd_close_fd() and the cross-request unlock path free these\nretained file_lock objects directly. If a dependent waiter is still\nattached, locks_release_private() hits\nBUG_ON(!list_empty(&flc->flc_blocked_requests)). The same lifetime\nmismatch can leave a freed ksmbd_lock reachable through its request-local\nllist.\n\nDetach the file_lock from the blocked-request graph before freeing it in\nthe close, cross-request unlock, and rollback paths. locks_delete_block()\nalso wakes requests chained below the object. Remove llist when a\ncompleted lock is published so a globally visible ksmbd_lock no longer\npoints into the submitting worker's stack."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"4e8b69c06bd6583ec11abef4fae50c2c8d5f3679","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"d20d3f6ad8b0b6f4e1bb32cdf7eca251962e8f04","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"d31db79cfaa9fce6649772ad279779473ba8aef9","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"f77d2accafca529e0ea3f979eb6e6cf1dac05c90","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"514a0b2bc949963497e66cacd433f65dc768a71d","versionType":"git"},{"version":"d63528eb0d43c4796c42aad56889dec12cf4e122","status":"affected","lessThan":"215e8816b1ac25176d911abb8704390413ccee4b","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/smb2pdu.c","fs/smb/server/vfs_cache.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.15","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.6","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/smb2pdu.c","fs/smb/server/vfs_cache.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/4e8b69c06bd6583ec11abef4fae50c2c8d5f3679"},{"url":"https://git.kernel.org/stable/c/d20d3f6ad8b0b6f4e1bb32cdf7eca251962e8f04"},{"url":"https://git.kernel.org/stable/c/d31db79cfaa9fce6649772ad279779473ba8aef9"},{"url":"https://git.kernel.org/stable/c/f77d2accafca529e0ea3f979eb6e6cf1dac05c90"},{"url":"https://git.kernel.org/stable/c/514a0b2bc949963497e66cacd433f65dc768a71d"},{"url":"https://git.kernel.org/stable/c/215e8816b1ac25176d911abb8704390413ccee4b"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:34:28.100Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.12.114"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.18.57"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"7.2.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}