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 A93B5386576; Sun, 31 May 2026 12:07:10 +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=1780229231; cv=none; b=KqdwuUBdiiRRFz+98LkYoOO4pAmsO2djtIObyoirq4g/C9cJVfEwOhTiIExdDRaYOrq7ACuIiB0jLSFF/TgEn4WkMN9jbgyZ2RxbZYK+9wPGD8xqNT9pxU8PxXg3vqTvKPe6p0C4PDKbDu3PhMmzi95yddaVxiTL40oFdh6MWRg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780229231; c=relaxed/simple; bh=64u5Ul+xqTSb5rRj1hmUXpte0cuXwsv1Env2BJhxpn8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Gisp9VRSOmeBI6z93BDDwVIbaLfZOPzGI/DBEsMTiCGqbrp6fWwIVSHxrUsdOaZsEnvxmQLls6m5sQKZT6bbAnsglR5Seb4QxvttGiOuDVYwY63+41A1eo3jiCfguuZLytWSmpGaFQyt9WY3m0bI91CkqkFyN7LxmpHdwkuvps8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Lq82Z7Wk; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Lq82Z7Wk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6B5A71F00898; Sun, 31 May 2026 12:07:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780229230; bh=kZNbxB7wKYlevcJJobkWbc4vfQxHHhzun3nc92sGqM0=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=Lq82Z7WksVaFNhPcOaEEZjmNYIymItxaXVPUeq26BAuYs6eu0cWplXO1hEnljZe+N ZR6Tyo5ErTVWuyUaijDCyCQYMQO/JvOXMRe0aPfFZRBoAXt7vI+pPaiCZLZ0YcHPa0 lmPEfT89ENwWjcUaOcOb9OEiVAynEt8b/ETeZQlpt/KqxhwIBG7P4o+ow41U4AXmjD uQcO9wBMMpb0fL7wMqW841Y6gzNdEKm7RWAx+43pHr6ehg2F/weOSxj+GdhEkten2M d7yZ6t7mt1joVoTX1sUTcfmEIZ4+EyHxQxibDcKZZiwf6rUgppu6LbBjQfKk6/XnUr biWGcUaPlZgtA== From: Jeff Layton Date: Sun, 31 May 2026 08:06:58 -0400 Subject: [PATCH 1/6] nfsd: size fh_verify server sockaddr slot by xpt_locallen Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260531-nfsd-testing-v1-1-7bfa481b0540@kernel.org> References: <20260531-nfsd-testing-v1-0-7bfa481b0540@kernel.org> In-Reply-To: <20260531-nfsd-testing-v1-0-7bfa481b0540@kernel.org> To: Chuck Lever , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey , David Howells , Al Viro , Rick Macklem , Chris Mason Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Jeff Layton X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=2698; i=jlayton@kernel.org; h=from:subject:message-id; bh=DaEpCa5QFYyJa/GWwlqRdWIspy4HMPc365Q8vph+iXE=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBqHCRqideoPPwp9ZgCO2ZqBCx9JHgea5jEcvO+q j9ZuSpIVxGJAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCahwkagAKCRAADmhBGVaC Fb6TEADRwsCcMHDF8qo3BpNJyHaV5kVibgcPcBMOmY0LxSB9gn639quiU8bHC4v1D4KjCmq8pMc pB9OuxS1G9qDU/oFD6QwwExKORZqhc3pDoURI66B4UOu8j0Ap1cwOidftKERK1p4JnPzp2OSV85 7U7PagdJUbg6pC25p8f8uT2a4XFl2SFoosUptG8xs4cGLZrxSfU5mGqScHQnrP191QCqf6VP/SU rTnmSfIGRZsBgS50zzW0nFV2sOB5a9Ja/PMC/WxPm7y0nBBvAM52TvLeTIJ1Uqvaif0HXOP48D8 s8Rat0flsPQlMq3mcu0yihKnpvcDt6fwBfMuUjx+CSziGMHAFW6xu6/sqgF6RboJbXZ7R1O8OsE DLutRqRz0r25bb4xLzXVpZkChWqjpl2veNUUaEeZE5tf0ugqrayqrN/za9L5CoYeEysfHnYPa6g lgHnnxKa5rI7ldttsen6JwRpwwbEpC7EW9bnuidNsvdyTHThU3a6XG4DHub4Bdzr0Ci7CmzCKi/ 1eLDJi/2vHzMrRxdmJ5baMpb0lI3VECJQ5Fg3QhWTD5uXqRpCxmAKYzATecfqW0YG3utjZFERoM XiIOVf04udHa9hL4vsmOU4OV4o3gfvqlhqF0/VMEWd1PbmthJYiDpLURlQRc1H6Se+1PlUEFm9y YyUNlM/xULKIoCA== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 From: Chris Mason 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()") Assisted-by: kres:claude-opus-4-7 Signed-off-by: Chris Mason --- 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 9917c0440522..db0a0dc70660 100644 --- a/fs/nfsd/trace.h +++ b/fs/nfsd/trace.h @@ -272,7 +272,7 @@ TRACE_EVENT_CONDITION(nfsd_fh_verify, TP_CONDITION(rqstp != NULL), 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) @@ -311,7 +311,7 @@ TRACE_EVENT_CONDITION(nfsd_fh_verify_err, TP_CONDITION(rqstp != NULL && 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) -- 2.54.0