From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 803DA4756BB for ; Wed, 16 Sep 2026 08:49:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789548565; cv=none; b=h3kR9krc16a4HwBPGTUA92uBRI7CCY41ZAaRB7oOXs118vtyyE/lMm6qVtOZrryJgbnFYe7O4LwCNhYbBHPRSXBTKiqTDkC8n1QuQGOOaWFvOckXnX1ww2JZ5Xv/dCrYNaGRhLs0AqhuabpWn+UbVp+1b+cAwBmnGA5qeanbmiA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789548565; c=relaxed/simple; bh=bDw4/DMR2HHeaIb2uWmUqrGmEfEtoyEXeBSGQrM2EWo=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=LXh3o91tVRh1cFQVbilPkbQDkgxbgQA4Kc0A0PquIPOh5tyY7n7Vxs9c4xxAUsUFL28CoUBlhSVVsxOiIxoBkqW3Vr+6Ws5JXhhnfFRTjS2EikVkeaW9gUWQQoGzUnV58R+4vPshObMaHl9SbPUm56UZH62cn2rmosocX2ml9yw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=DpogT+98; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="DpogT+98" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 99F501F00893; Wed, 16 Sep 2026 08:49:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789548563; bh=KXt4Wjasd8EzAW3gLSWUmWQ2tXBpE4MUaPHZy+ARMyU=; h=From:To:Cc:Subject:Date:Reply-To; b=DpogT+986J8bcrxCTdCHH/x0sOogWY61YKo3qJdrIlKSI0zdIA24S2Y/YUaC7/mnZ RjfvfCxs9rjb0mLQKUnljTh+elaZNzSiSlliUgo9VxN2yxlj24Q/O+Gj9AyOc+9Qxa aAhbQZNbIOvztce9rEMDcTlsGGiI28E7Czl6vBOA= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89784: SUNRPC: check rpc_sockaddr2uaddr() return value in rpcb_register_inet4/6 Date: Wed, 16 Sep 2026 09:46:48 +0100 Message-ID: <2026091641-CVE-2026-89784-bbf5@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=4926; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=kVsPiAziwYCuG1hFFpBA/EYjQHa84GpZNJ7IEMabnu0=; b=owGbwMvMwCRo6H6F97bub03G02pJDFmrwgtLTE1vNR17EPLCcf8/zVkzxSc3qf9e91NsArvGz YzejUneHbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjARticMCy7OPlTCHN9vmexo WpjVFNmx+UToJoZ55qendvG0C7JN3f4rhCUiosNPkvkrAA== X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman 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. The Linux kernel CVE team has assigned CVE-2026-89784 to this issue. Affected and fixed versions =========================== Issue introduced in 3.2 with commit d77385f23830ee6c400569bac8b37e6eb3b7d360 and fixed in 5.10.270 with commit 04441b792ec40eb66349b5fab34b6a2090b5b2dd Issue introduced in 3.2 with commit d77385f23830ee6c400569bac8b37e6eb3b7d360 and fixed in 5.15.221 with commit 5a51c49ddb37b883566874aecc66bc5a2e617a96 Issue introduced in 3.2 with commit d77385f23830ee6c400569bac8b37e6eb3b7d360 and fixed in 6.1.188 with commit 4a6095de8cb1858e05bdf70b3e7d6d7645c25041 Issue introduced in 3.2 with commit d77385f23830ee6c400569bac8b37e6eb3b7d360 and fixed in 6.6.157 with commit 12bf3e0182ccdaf3b412756a756d3944a7dacaa9 Issue introduced in 3.2 with commit d77385f23830ee6c400569bac8b37e6eb3b7d360 and fixed in 6.12.110 with commit 4e01022974355732e748ec8ebc97c558cb624ffe Issue introduced in 3.2 with commit d77385f23830ee6c400569bac8b37e6eb3b7d360 and fixed in 6.18.52 with commit cda4aacfb0bbf5c0f90fd0b42c72c749635d1368 Issue introduced in 3.2 with commit d77385f23830ee6c400569bac8b37e6eb3b7d360 and fixed in 7.2.6 with commit eb476289c12cc22c8766f8a84eeb7ab46c4e8fb6 Issue introduced in 3.2 with commit d77385f23830ee6c400569bac8b37e6eb3b7d360 and fixed in 7.3-rc1 with commit fd22370226a0d8109045d0831fd5aaadee921693 Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-89784 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: net/sunrpc/rpcb_clnt.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/04441b792ec40eb66349b5fab34b6a2090b5b2dd https://git.kernel.org/stable/c/5a51c49ddb37b883566874aecc66bc5a2e617a96 https://git.kernel.org/stable/c/4a6095de8cb1858e05bdf70b3e7d6d7645c25041 https://git.kernel.org/stable/c/12bf3e0182ccdaf3b412756a756d3944a7dacaa9 https://git.kernel.org/stable/c/4e01022974355732e748ec8ebc97c558cb624ffe https://git.kernel.org/stable/c/cda4aacfb0bbf5c0f90fd0b42c72c749635d1368 https://git.kernel.org/stable/c/eb476289c12cc22c8766f8a84eeb7ab46c4e8fb6 https://git.kernel.org/stable/c/fd22370226a0d8109045d0831fd5aaadee921693