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CVE-2026-89784

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: check rpc_sockaddr2uaddr() return value in rpcb_register_inet4/6 rpcb_register_inet4() and rpcb_register_inet6() store the result of rpc_sockaddr2uaddr() into map->r_addr without checking it for NULL. rpc_sockaddr2uaddr() returns NULL when its final kstrdup() fails, and the unchecked NULL is then carried into the synchronous RPCBPROC_SET encode path: rpcb_register_call() -> rpc_call_sync() -> rpcb_enc_getaddr() -> encode_rpcb_string(), whose first statement is strlen(string), dereferencing NULL and oopsing the kernel. The crash reproduces under failslab on v6.12; with KASAN the NULL dereference surfaces as a fault on the shadow of address zero: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000 [#1] PREEMPT SMP KASAN RIP: 0010:strlen (lib/string.c:409) Call Trace: encode_rpcb_string (net/sunrpc/rpcb_clnt.c:890) rpcb_enc_getaddr (net/sunrpc/rpcb_clnt.c:910) rpcauth_wrap_req_encode (net/sunrpc/auth.c:745) call_encode (net/sunrpc/clnt.c:1966) __rpc_execute (net/sunrpc/sched.c:952) rpc_run_task (net/sunrpc/clnt.c:1243) rpc_call_sync (net/sunrpc/clnt.c:1272) rpcb_v4_register (net/sunrpc/rpcb_clnt.c:500) svc_generic_rpcbind_set nfsd_rpcbind_set svc_register svc_setup_socket svc_addsock write_ports nfsctl_transaction_write vfs_write The crash is reachable when an in-kernel RPC service (nfsd, lockd, nfs-callback) registers with the local rpcbind under enough memory pressure for the small GFP_KERNEL kstrdup() in rpc_sockaddr2uaddr() to fail. The asynchronous getport path already handles this exact failure mode by returning -ENOMEM; only the two register helpers omit the check. Mirror that handling: bail out with -ENOMEM when rpc_sockaddr2uaddr() returns NULL, before the address is fed into the encoder.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-16 09:17:09.060000
Last modified
2026-10-19 09:18:21.953000
View original CVE JSON
{
  "id": "CVE-2026-89784",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-16T09:17:09.060",
  "lastModified": "2026-10-19T09:18:21.953",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nSUNRPC: check rpc_sockaddr2uaddr() return value in rpcb_register_inet4/6\n\nrpcb_register_inet4() and rpcb_register_inet6() store the result of\nrpc_sockaddr2uaddr() into map->r_addr without checking it for NULL.\nrpc_sockaddr2uaddr() returns NULL when its final kstrdup() fails, and\nthe unchecked NULL is then carried into the synchronous RPCBPROC_SET\nencode path: rpcb_register_call() -> rpc_call_sync() ->\nrpcb_enc_getaddr() -> encode_rpcb_string(), whose first statement is\nstrlen(string), dereferencing NULL and oopsing the kernel.\n\nThe crash reproduces under failslab on v6.12; with KASAN the NULL\ndereference surfaces as a fault on the shadow of address zero:\n\n Oops: general protection fault, probably for non-canonical address\n       0xdffffc0000000000 [#1] PREEMPT SMP KASAN\n RIP: 0010:strlen (lib/string.c:409)\n Call Trace:\n  encode_rpcb_string (net/sunrpc/rpcb_clnt.c:890)\n  rpcb_enc_getaddr (net/sunrpc/rpcb_clnt.c:910)\n  rpcauth_wrap_req_encode (net/sunrpc/auth.c:745)\n  call_encode (net/sunrpc/clnt.c:1966)\n  __rpc_execute (net/sunrpc/sched.c:952)\n  rpc_run_task (net/sunrpc/clnt.c:1243)\n  rpc_call_sync (net/sunrpc/clnt.c:1272)\n  rpcb_v4_register (net/sunrpc/rpcb_clnt.c:500)\n  svc_generic_rpcbind_set\n  nfsd_rpcbind_set\n  svc_register\n  svc_setup_socket\n  svc_addsock\n  write_ports\n  nfsctl_transaction_write\n  vfs_write\n\nThe crash is reachable when an in-kernel RPC service (nfsd, lockd,\nnfs-callback) registers with the local rpcbind under enough memory\npressure for the small GFP_KERNEL kstrdup() in rpc_sockaddr2uaddr() to\nfail. The asynchronous getport path already handles this exact failure\nmode by returning -ENOMEM; only the two register helpers omit the check.\n\nMirror that handling: bail out with -ENOMEM when rpc_sockaddr2uaddr()\nreturns NULL, before the address is fed into the encoder."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/sunrpc/rpcb_clnt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "d77385f23830ee6c400569bac8b37e6eb3b7d360",
              "lessThan": "04441b792ec40eb66349b5fab34b6a2090b5b2dd",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d77385f23830ee6c400569bac8b37e6eb3b7d360",
              "lessThan": "5a51c49ddb37b883566874aecc66bc5a2e617a96",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d77385f23830ee6c400569bac8b37e6eb3b7d360",
              "lessThan": "4a6095de8cb1858e05bdf70b3e7d6d7645c25041",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d77385f23830ee6c400569bac8b37e6eb3b7d360",
              "lessThan": "12bf3e0182ccdaf3b412756a756d3944a7dacaa9",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d77385f23830ee6c400569bac8b37e6eb3b7d360",
              "lessThan": "4e01022974355732e748ec8ebc97c558cb624ffe",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d77385f23830ee6c400569bac8b37e6eb3b7d360",
              "lessThan": "cda4aacfb0bbf5c0f90fd0b42c72c749635d1368",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d77385f23830ee6c400569bac8b37e6eb3b7d360",
              "lessThan": "eb476289c12cc22c8766f8a84eeb7ab46c4e8fb6",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "d77385f23830ee6c400569bac8b37e6eb3b7d360",
              "lessThan": "fd22370226a0d8109045d0831fd5aaadee921693",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/sunrpc/rpcb_clnt.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "3.2",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "3.2",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.10.270",
              "lessThanOrEqual": "5.10.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "5.15.221",
              "lessThanOrEqual": "5.15.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.188",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.157",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.110",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.52",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.6",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/04441b792ec40eb66349b5fab34b6a2090b5b2dd",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/12bf3e0182ccdaf3b412756a756d3944a7dacaa9",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4a6095de8cb1858e05bdf70b3e7d6d7645c25041",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4e01022974355732e748ec8ebc97c558cb624ffe",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5a51c49ddb37b883566874aecc66bc5a2e617a96",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cda4aacfb0bbf5c0f90fd0b42c72c749635d1368",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/eb476289c12cc22c8766f8a84eeb7ab46c4e8fb6",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fd22370226a0d8109045d0831fd5aaadee921693",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}