{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31477","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-03-09T15:48:24.098Z","datePublished":"2026-04-22T13:54:05.470Z","dateUpdated":"2026-05-11T22:09:29.536Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T22:09:29.536Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix memory leaks and NULL deref in smb2_lock()\n\nsmb2_lock() has three error handling issues after list_del() detaches\nsmb_lock from lock_list at no_check_cl:\n\n1) If vfs_lock_file() returns an unexpected error in the non-UNLOCK\n   path, goto out leaks smb_lock and its flock because the out:\n   handler only iterates lock_list and rollback_list, neither of\n   which contains the detached smb_lock.\n\n2) If vfs_lock_file() returns -ENOENT in the UNLOCK path, goto out\n   leaks smb_lock and flock for the same reason.  The error code\n   returned to the dispatcher is also stale.\n\n3) In the rollback path, smb_flock_init() can return NULL on\n   allocation failure.  The result is dereferenced unconditionally,\n   causing a kernel NULL pointer dereference.  Add a NULL check to\n   prevent the crash and clean up the bookkeeping; the VFS lock\n   itself cannot be rolled back without the allocation and will be\n   released at file or connection teardown.\n\nFix cases 1 and 2 by hoisting the locks_free_lock()/kfree() to before\nthe if(!rc) check in the UNLOCK branch so all exit paths share one\nfree site, and by freeing smb_lock and flock before goto out in the\nnon-UNLOCK branch.  Propagate the correct error code in both cases.\nFix case 3 by wrapping the VFS unlock in an if(rlock) guard and adding\na NULL check for locks_free_lock(rlock) in the shared cleanup.\n\nFound via call-graph analysis using sqry."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"}}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/smb2pdu.c"],"versions":[{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"cdac6f7e7e428dc70e3b5898ac6999a72ed13993","status":"affected","versionType":"git"},{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"c9b95ef6f5039f19e46c3a521a4fe1752d91dfe9","status":"affected","versionType":"git"},{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"91aeaa7256006d79a37298f5a1df23325db91599","status":"affected","versionType":"git"},{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"3cdacd11b41569ce75b3162142240f2355e04900","status":"affected","versionType":"git"},{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"aab42f0795620cf0d3955a520f571f697d0f9a2a","status":"affected","versionType":"git"},{"version":"e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9","lessThan":"309b44ed684496ed3f9c5715d10b899338623512","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/smb/server/smb2pdu.c"],"versions":[{"version":"5.15","status":"affected"},{"version":"0","lessThan":"5.15","status":"unaffected","versionType":"semver"},{"version":"6.1.168","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.131","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.80","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.21","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.11","lessThanOrEqual":"6.19.*","status":"unaffected","versionType":"semver"},{"version":"7.0","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.1.168"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.6.131"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.12.80"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.18.21"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.19.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"7.0"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/cdac6f7e7e428dc70e3b5898ac6999a72ed13993"},{"url":"https://git.kernel.org/stable/c/c9b95ef6f5039f19e46c3a521a4fe1752d91dfe9"},{"url":"https://git.kernel.org/stable/c/91aeaa7256006d79a37298f5a1df23325db91599"},{"url":"https://git.kernel.org/stable/c/3cdacd11b41569ce75b3162142240f2355e04900"},{"url":"https://git.kernel.org/stable/c/aab42f0795620cf0d3955a520f571f697d0f9a2a"},{"url":"https://git.kernel.org/stable/c/309b44ed684496ed3f9c5715d10b899338623512"}],"title":"ksmbd: fix memory leaks and NULL deref in smb2_lock()","x_generator":{"engine":"bippy-1.2.0"}}}}