{"cve":"CVE-2022-50401","nvd":{"published":"2025-09-18T16:15:42.353","modified":"2026-08-04T10:18:14.727","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: under NFSv4.1, fix double svc_xprt_put on rpc_create failure\n\nOn error situation `clp->cl_cb_conn.cb_xprt` should not be given\na reference to the xprt otherwise both client cleanup and the\nerror handling path of the caller call to put it. Better to\ndelay handing over the reference to a later branch.\n\n[   72.530665] refcount_t: underflow; use-after-free.\n[   72.531933] WARNING: CPU: 0 PID: 173 at lib/refcount.c:28 refcount_warn_saturate+0xcf/0x120\n[   72.533075] Modules linked in: nfsd(OE) nfsv4(OE) nfsv3(OE) nfs(OE) lockd(OE) compat_nfs_ssc(OE) nfs_acl(OE) rpcsec_gss_krb5(OE) auth_rpcgss(OE) rpcrdma(OE) dns_resolver fscache netfs grace rdma_cm iw_cm ib_cm sunrpc(OE) mlx5_ib mlx5_core mlxfw pci_hyperv_intf ib_uverbs ib_core xt_MASQUERADE nf_conntrack_netlink nft_counter xt_addrtype nft_compat br_netfilter bridge stp llc nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set overlay nf_tables nfnetlink crct10dif_pclmul crc32_pclmul ghash_clmulni_intel xfs serio_raw virtio_net virtio_blk net_failover failover fuse [last unloaded: sunrpc]\n[   72.540389] CPU: 0 PID: 173 Comm: kworker/u16:5 Tainted: G           OE     5.15.82-dan #1\n[   72.541511] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.16.0-3.module+el8.7.0+1084+97b81f61 04/01/2014\n[   72.542717] Workqueue: nfsd4_callbacks nfsd4_run_cb_work [nfsd]\n[   72.543575] RIP: 0010:refcount_warn_saturate+0xcf/0x120\n[   72.544299] Code: 55 00 0f 0b 5d e9 01 50 98 00 80 3d 75 9e 39 08 00 0f 85 74 ff ff ff 48 c7 c7 e8 d1 60 8e c6 05 61 9e 39 08 01 e8 f6 51 55 00 <0f> 0b 5d e9 d9 4f 98 00 80 3d 4b 9e 39 08 00 0f 85 4c ff ff ff 48\n[   72.546666] RSP: 0018:ffffb3f841157cf0 EFLAGS: 00010286\n[   72.547393] RAX: 0000000000000026 RBX: ffff89ac6231d478 RCX: 0000000000000000\n[   72.548324] RDX: ffff89adb7c2c2c0 RSI: ffff89adb7c205c0 RDI: ffff89adb7c205c0\n[   72.549271] RBP: ffffb3f841157cf0 R08: 0000000000000000 R09: c0000000ffefffff\n[   72.550209] R10: 0000000000000001 R11: ffffb3f841157ad0 R12: ffff89ac6231d180\n[   72.551142] R13: ffff89ac6231d478 R14: ffff89ac40c06180 R15: ffff89ac6231d4b0\n[   72.552089] FS:  0000000000000000(0000) GS:ffff89adb7c00000(0000) knlGS:0000000000000000\n[   72.553175] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[   72.553934] CR2: 0000563a310506a8 CR3: 0000000109a66000 CR4: 0000000000350ef0\n[   72.554874] Call Trace:\n[   72.555278]  <TASK>\n[   72.555614]  svc_xprt_put+0xaf/0xe0 [sunrpc]\n[   72.556276]  nfsd4_process_cb_update.isra.11+0xb7/0x410 [nfsd]\n[   72.557087]  ? update_load_avg+0x82/0x610\n[   72.557652]  ? cpuacct_charge+0x60/0x70\n[   72.558212]  ? dequeue_entity+0xdb/0x3e0\n[   72.558765]  ? queued_spin_unlock+0x9/0x20\n[   72.559358]  nfsd4_run_cb_work+0xfc/0x270 [nfsd]\n[   72.560031]  process_one_work+0x1df/0x390\n[   72.560600]  worker_thread+0x37/0x3b0\n[   72.561644]  ? process_one_work+0x390/0x390\n[   72.562247]  kthread+0x12f/0x150\n[   72.562710]  ? set_kthread_struct+0x50/0x50\n[   72.563309]  ret_from_fork+0x22/0x30\n[   72.563818]  </TASK>\n[   72.564189] ---[ end trace 031117b1c72ec616 ]---\n[   72.566019] list_add corruption. next->prev should be prev (ffff89ac4977e538), but was ffff89ac4763e018. (next=ffff89ac4763e018).\n[   72.567647] ------------[ cut here ]------------","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-415"],"references":["https://git.kernel.org/stable/c/15fc60aa5bdcf6d5f93000d3d00579fc67632ee0","https://git.kernel.org/stable/c/3bc8edc98bd43540dbe648e4ef91f443d6d20a24","https://git.kernel.org/stable/c/707bcca9616002d204091ca7c4d1d91151104332","https://git.kernel.org/stable/c/9b4ae8c42d2ff09ed7c5832ccce5684c55e5ed23","https://git.kernel.org/stable/c/a472f069ced8601979f53c13c0cf20236074ed46"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:10:08.713834912+00:00"},"epss":{"cve":"CVE-2022-50401","score":0.00441,"percentile":0.38317,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}