{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89714","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.751Z","datePublished":"2026-09-11T19:46:28.476Z","dateUpdated":"2026-09-11T19:46:28.476Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-11T19:46:28.476Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFS: fix delegation_hash_table leak when nfs4_server_common_setup() fails\n\nnfs4_server_common_setup() allocates server->delegation_hash_table\nfirst, but server->destroy - the only path that frees the table via\nnfs4_destroy_server() - is not assigned until the very end of the\nfunction. If any intermediate step fails (the is_ds_only_client()\ncheck, nfs4_init_session(), nfs4_get_rootfh(), or nfs_probe_server()),\nthe function returns with server->destroy still NULL, so the caller's\nnfs_free_server() skips the destroy callback and the hash table is\nleaked (4 KiB per attempt with the default delegation watermark).\n\nThis is trivially reachable from userspace: every failed NFSv4 mount\nleaks one allocation. A client that persistently retries a mount that\ncannot succeed leaks kernel memory without bound. Observed in\nproduction where a Longhorn backup poller retried mount.nfs4 against\nan NFSv3-only server roughly 10 times per second, leaking ~3.4 GiB of\nunreclaimable slab (kmalloc-rnd-13-4k) per day; the node accumulated\n12 GiB of leaked slab before the source was identified via the\nkmem:kmalloc tracepoint (call_site=nfs4_delegation_hash_alloc).\n\nReproducer:\n\n  # server exports NFSv3 only (or export path absent for v4)\n  while :; do mount -t nfs4 <server>:/missing /mnt; done\n  # watch SUnreclaim in /proc/meminfo grow 4 KiB per iteration\n\nFree the table on the error paths between the allocation and the\nassignment of server->destroy."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["fs/nfs/nfs4client.c"],"versions":[{"version":"f5b3108e6a14418b120a3c38ca589b8d6cf87627","lessThan":"f3adf1643517357221422c05986d6de5df7b9913","status":"affected","versionType":"git"},{"version":"f5b3108e6a14418b120a3c38ca589b8d6cf87627","lessThan":"0fd2b9687dae36be5b84eab39b4c627bb7ab33b3","status":"affected","versionType":"git"},{"version":"f5b3108e6a14418b120a3c38ca589b8d6cf87627","lessThan":"2092f5b38f88be306140c77aeeeb43fc1adacacc","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/nfs/nfs4client.c"],"versions":[{"version":"6.17","status":"affected"},{"version":"0","lessThan":"6.17","status":"unaffected","versionType":"semver"},{"version":"6.18.50","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.4","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","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":"6.17","versionEndExcluding":"6.18.50"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17","versionEndExcluding":"7.2.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.17","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/f3adf1643517357221422c05986d6de5df7b9913"},{"url":"https://git.kernel.org/stable/c/0fd2b9687dae36be5b84eab39b4c627bb7ab33b3"},{"url":"https://git.kernel.org/stable/c/2092f5b38f88be306140c77aeeeb43fc1adacacc"}],"title":"NFS: fix delegation_hash_table leak when nfs4_server_common_setup() fails","x_generator":{"engine":"bippy-1.2.0"}}}}