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 727E1390C9F; Thu, 30 Jul 2026 15:51:50 +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=1785426711; cv=none; b=S+SnuAPDU1pId01EQ7ZiwXQMcTQkxDktbhpJspQOfPkyg98shoStJM2sYCtZJxWPx8H8s9HR8SQZVQk3Q0m0piOgLIzt9f5+xMaT5AbXWx2jcL6dfr4q2HPgpMeyXJK8Ukj1E05AaN1srVBv7is5EAOsWfLF9V0eyiN1Rdj0qkc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785426711; c=relaxed/simple; bh=7aip1pOrCJHngeUp+1FnNfUSr6PFKoe+38aDVBQ+Ykw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rTd+u7vOmHM2kzBLI0ga0tUFREWLr3lBjgFO6Apkkf++e7W75Kz+MEK7RKVL8wzlG0ZLIaPySUgXSgmvWdAL1qhFvbpfIL+kID0fHSyRXREKkz2V77FWesMLZuS1zyxbNr4Hr1/t5YTj6sMvdDa5GQtJF4b3lqZ7vCPzcIW6doI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=W60S/VAS; 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="W60S/VAS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CE8D81F000E9; Thu, 30 Jul 2026 15:51:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785426710; bh=4CqSU1MuHF+GzU23i4YOLfRTmE7fwwa/JE9/tm4s3go=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=W60S/VASmYcep35GSVM92rxcA1ZYbWtc+n45O48wpHWMXeczyoBI3NauaRzMrFrWQ 1jiebrQq66POzeJQsaZ3/q/VTK4XNhU2O5mMq4IK6+QtCht/G3TN8ly6noAxkEEWuN g0V6kOGfUOgIEmrG5d1rd/YCB09sirfs0OvH1mIE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jeff Layton , NeilBrown , Chuck Lever , Sasha Levin Subject: [PATCH 6.12 513/602] sunrpc: allocate a separate bvec array for socket sends Date: Thu, 30 Jul 2026 16:15:05 +0200 Message-ID: <20260730141446.781523139@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141435.976815864@linuxfoundation.org> References: <20260730141435.976815864@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton [ Upstream commit 6b3b697d65d46a0f640216a3f6c72856c159c567 ] svc_tcp_sendmsg() calls xdr_buf_to_bvec() with the second slot of rq_bvec as the start, but doesn't reduce the array length by one, which could lead to an array overrun. Also, rq_bvec is always rq_maxpages in length, which can be too short in some cases, since the TCP record marker consumes a slot. Fix both problems by adding a separate bvec array to the svc_sock that is specifically for sending. For TCP, make this array one slot longer than rq_maxpages, to account for the record marker. For UDP, only allocate as large an array as we need since it's limited to 64k of payload. Signed-off-by: Jeff Layton Reviewed-by: NeilBrown Signed-off-by: Chuck Lever Stable-dep-of: 18c1cc698861 ("SUNRPC: Return an error from xdr_buf_to_bvec() on overflow") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- include/linux/sunrpc/svcsock.h | 3 +++ net/sunrpc/svcsock.c | 37 ++++++++++++++++++++++++++++--------- 2 files changed, 31 insertions(+), 9 deletions(-) --- a/include/linux/sunrpc/svcsock.h +++ b/include/linux/sunrpc/svcsock.h @@ -26,6 +26,9 @@ struct svc_sock { void (*sk_odata)(struct sock *); void (*sk_owspace)(struct sock *); + /* For sends (protected by xpt_mutex) */ + struct bio_vec *sk_bvec; + /* private TCP part */ /* On-the-wire fragment header: */ __be32 sk_marker; --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -68,6 +68,17 @@ #define RPCDBG_FACILITY RPCDBG_SVCXPRT +/* + * For UDP: + * 1 for header page + * enough pages for RPCSVC_MAXPAYLOAD_UDP + * 1 in case payload is not aligned + * 1 for tail page + */ +enum { + SUNRPC_MAX_UDP_SENDPAGES = 1 + RPCSVC_MAXPAYLOAD_UDP / PAGE_SIZE + 1 + 1 +}; + /* To-do: to avoid tying up an nfsd thread while waiting for a * handshake request, the request could instead be deferred. */ @@ -750,15 +761,14 @@ static int svc_udp_sendto(struct svc_rqs if (svc_xprt_is_dead(xprt)) goto out_notconn; - count = xdr_buf_to_bvec(rqstp->rq_bvec, - ARRAY_SIZE(rqstp->rq_bvec), xdr); + count = xdr_buf_to_bvec(svsk->sk_bvec, SUNRPC_MAX_UDP_SENDPAGES, xdr); - iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, rqstp->rq_bvec, + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, svsk->sk_bvec, count, rqstp->rq_res.len); err = sock_sendmsg(svsk->sk_sock, &msg); if (err == -ECONNREFUSED) { /* ICMP error on earlier request. */ - iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, rqstp->rq_bvec, + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, svsk->sk_bvec, count, rqstp->rq_res.len); err = sock_sendmsg(svsk->sk_sock, &msg); } @@ -1248,19 +1258,19 @@ static int svc_tcp_sendmsg(struct svc_so *sentp = 0; /* The stream record marker is copied into a temporary page - * fragment buffer so that it can be included in rq_bvec. + * fragment buffer so that it can be included in sk_bvec. */ buf = page_frag_alloc(&svsk->sk_frag_cache, sizeof(marker), GFP_KERNEL); if (!buf) return -ENOMEM; memcpy(buf, &marker, sizeof(marker)); - bvec_set_virt(rqstp->rq_bvec, buf, sizeof(marker)); + bvec_set_virt(svsk->sk_bvec, buf, sizeof(marker)); - count = xdr_buf_to_bvec(rqstp->rq_bvec + 1, - ARRAY_SIZE(rqstp->rq_bvec) - 1, &rqstp->rq_res); + count = xdr_buf_to_bvec(svsk->sk_bvec + 1, RPCSVC_MAXPAGES, + &rqstp->rq_res); - iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, rqstp->rq_bvec, + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, svsk->sk_bvec, 1 + count, sizeof(marker) + rqstp->rq_res.len); ret = sock_sendmsg(svsk->sk_sock, &msg); page_frag_free(buf); @@ -1423,6 +1433,13 @@ static struct svc_sock *svc_setup_socket if (!svsk) return ERR_PTR(-ENOMEM); + svsk->sk_bvec = kcalloc(RPCSVC_MAXPAGES + 1, sizeof(*svsk->sk_bvec), + GFP_KERNEL); + if (!svsk->sk_bvec) { + kfree(svsk); + return ERR_PTR(-ENOMEM); + } + inet = sock->sk; if (pmap_register) { @@ -1432,6 +1449,7 @@ static struct svc_sock *svc_setup_socket inet->sk_protocol, ntohs(inet_sk(inet)->inet_sport)); if (err < 0) { + kfree(svsk->sk_bvec); kfree(svsk); return ERR_PTR(err); } @@ -1651,5 +1669,6 @@ static void svc_sock_free(struct svc_xpr if (pfc->va) __page_frag_cache_drain(virt_to_head_page(pfc->va), pfc->pagecnt_bias); + kfree(svsk->sk_bvec); kfree(svsk); }