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 BB56D38AC99; Sat, 17 Oct 2026 16:51:36 +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=1792255897; cv=none; b=eMjt0YWkoj+NkjKibhK8u/Jatu0lAhq1hbFJ7dRX5B7QmUvRR7JIUoAJ7fW+urTscPSJO7/vKSZ43ptfmkElBdZx8YTXNnpnjEGT4tRUN4mb1wTGkgcIeyKW9cWbXzetcnHiYWUmBd35HYQAPJNfbH5GijEMepr6sdubzHC1e/s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792255897; c=relaxed/simple; bh=qzMjM/FClBiPoGEoQCj1WZ+9fomSSUVP1NBwiAGHF2A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QVur0A+DCDFSaif40QL0YzFz9+fHCRoHHTfVg/bKZ2U8KZX7SY4j6DPutARSpJ3QM9fPEry+M0gWpe2fA5y+SY1Z8fe+1CGRWupGAC5ulcu2rF8WLL6AK9iHMDpg3GNWJOtEUw6NH84UQilD923eg8MAIPea0pJ/0TAEbK+dPZU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2hcTUJek; 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="2hcTUJek" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 16FA21F000C4; Sat, 17 Oct 2026 16:51:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792255896; bh=rWRudD3nqCsIcloIjUTyeuswqyy6M7k3WBzsBQGGQ2U=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=2hcTUJek2a6TE2le6u8FQViGG4Dik7xHMFManDM+0WDykLEnhzlb6OAX0y0cw/MfX z7CsyzmTVkDRi1h+qT2S/GPRDCUOE3Imm/RS+m0TZMqBCNb8AO7x5BlP8ugI+Q2wjL C+LbGD9bRwsdyxGygMl251x8zNK8+9zrJFnp5FxM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chris Mason , Chuck Lever , Sasha Levin Subject: [PATCH 6.6 0056/1674] nfsd: size fh_verify server sockaddr slot by xpt_locallen Date: Sat, 17 Oct 2026 17:38:48 +0200 Message-ID: <20261017160432.576917756@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261017160431.119607952@linuxfoundation.org> References: <20261017160431.119607952@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chris Mason [ Upstream commit 71d068490098b1d23c63b2345e40675d3a1ca763 ] The nfsd_fh_verify and nfsd_fh_verify_err tracepoints declare the server sockaddr slot sized by xpt_remotelen but fill it from xpt_local using xpt_locallen: TP_STRUCT__entry( ... __sockaddr(server, rqstp->rq_xprt->xpt_remotelen) ... ) TP_fast_assign( ... __assign_sockaddr(server, &rqstp->rq_xprt->xpt_local, rqstp->rq_xprt->xpt_locallen); ... ) When xpt_locallen exceeds xpt_remotelen, __assign_sockaddr's memcpy writes past the reserved ring-buffer slot. In the reverse direction (xpt_locallen < xpt_remotelen) the slot is oversized and the unwritten tail leaks prior ring-buffer contents to trace consumers. The write-past-end case is reachable on NFS/UDP. svc_xprt_set_remote() is only called from svc_tcp_accept() (net/sunrpc/svcsock.c) and from the RDMA connect path; svc_create_socket() for UDP calls only svc_xprt_set_local(), so xpt_remotelen stays 0 for the xprt's lifetime. Every fh_verify trace for an NFSv2/v3-over-UDP request then copies 16 or 28 bytes from xpt_local into a zero-byte slot. The other NFSD tracepoints that record the server address (NFSD_TRACE_PROC_CALL_FIELDS, NFSD_TRACE_PROC_RES_FIELDS, SVC_RQST_ENDPOINT_FIELDS) already size the server slot by xpt_locallen; nfsd_fh_verify and nfsd_fh_verify_err were the only exceptions. Fix by sizing the server slot with xpt_locallen so the declared slot matches the copy length. The client slot and its assignment already agree on xpt_remotelen and are left untouched. Fixes: 051382885552 ("NFSD: Instrument fh_verify()") Fixes: 948755efc951 ("NFSD: Replace dprintk() call site in fh_verify()") Cc: stable@vger.kernel.org Assisted-by: kres:claude-opus-4-7 Signed-off-by: Chris Mason Link: https://patch.msgid.link/20260531-nfsd-testing-v1-1-7bfa481b0540@kernel.org Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- fs/nfsd/trace.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h index d7ed49eef5911..6e57a9dba1a59 100644 --- a/fs/nfsd/trace.h +++ b/fs/nfsd/trace.h @@ -201,7 +201,7 @@ TRACE_EVENT(nfsd_fh_verify, TP_ARGS(rqstp, fhp, type, access), TP_STRUCT__entry( __field(unsigned int, netns_ino) - __sockaddr(server, rqstp->rq_xprt->xpt_remotelen) + __sockaddr(server, rqstp->rq_xprt->xpt_locallen) __sockaddr(client, rqstp->rq_xprt->xpt_remotelen) __field(u32, xid) __field(u32, fh_hash) @@ -240,7 +240,7 @@ TRACE_EVENT_CONDITION(nfsd_fh_verify_err, TP_CONDITION(error), TP_STRUCT__entry( __field(unsigned int, netns_ino) - __sockaddr(server, rqstp->rq_xprt->xpt_remotelen) + __sockaddr(server, rqstp->rq_xprt->xpt_locallen) __sockaddr(client, rqstp->rq_xprt->xpt_remotelen) __field(u32, xid) __field(u32, fh_hash) -- 2.53.0