From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9A391C64EC4 for ; Fri, 10 Mar 2023 14:31:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232505AbjCJObn (ORCPT ); Fri, 10 Mar 2023 09:31:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232542AbjCJOb3 (ORCPT ); Fri, 10 Mar 2023 09:31:29 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26E3A367D7 for ; Fri, 10 Mar 2023 06:30:37 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id C11C4B822AD for ; Fri, 10 Mar 2023 14:30:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3C6E7C433EF; Fri, 10 Mar 2023 14:30:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678458635; bh=s45eB0R8juTjlWTD+m+madG1BptmyRT70x9JDqDwhck=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZNWpL6wtJ4KiaKWlVupuSoojRwUIJ6k0RfiTbb8YUSEJ0BAst2po8P570ff59XBFq 5ZrZZNrSa6mZcj97ErGb+nq7El82VCGiSrR7/jaA6g2KwWiuSDE4gaBUcOESBNBJrQ /iy/7j4GuePBaFNTsE9uX74Ypb7Mxc48xeRq7JGw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Jakub Sitnicki , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 094/357] selftests/net: Interpret UDP_GRO cmsg data as an int value Date: Fri, 10 Mar 2023 14:36:23 +0100 Message-Id: <20230310133738.144172649@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133733.973883071@linuxfoundation.org> References: <20230310133733.973883071@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jakub Sitnicki [ Upstream commit 436864095a95fcc611c20c44a111985fa9848730 ] Data passed to user-space with a (SOL_UDP, UDP_GRO) cmsg carries an int (see udp_cmsg_recv), not a u16 value, as strace confirms: recvmsg(8, {msg_name=..., msg_iov=[{iov_base="\0\0..."..., iov_len=96000}], msg_iovlen=1, msg_control=[{cmsg_len=20, <-- sizeof(cmsghdr) + 4 cmsg_level=SOL_UDP, cmsg_type=0x68}], <-- UDP_GRO msg_controllen=24, msg_flags=0}, 0) = 11200 Interpreting the data as an u16 value won't work on big-endian platforms. Since it is too late to back out of this API decision [1], fix the test. [1]: https://lore.kernel.org/netdev/20230131174601.203127-1-jakub@cloudflare.com/ Fixes: 3327a9c46352 ("selftests: add functionals test for UDP GRO") Suggested-by: Eric Dumazet Signed-off-by: Jakub Sitnicki Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- tools/testing/selftests/net/udpgso_bench_rx.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/net/udpgso_bench_rx.c b/tools/testing/selftests/net/udpgso_bench_rx.c index 4058c7451e70d..f35a924d4a303 100644 --- a/tools/testing/selftests/net/udpgso_bench_rx.c +++ b/tools/testing/selftests/net/udpgso_bench_rx.c @@ -214,11 +214,10 @@ static void do_verify_udp(const char *data, int len) static int recv_msg(int fd, char *buf, int len, int *gso_size) { - char control[CMSG_SPACE(sizeof(uint16_t))] = {0}; + char control[CMSG_SPACE(sizeof(int))] = {0}; struct msghdr msg = {0}; struct iovec iov = {0}; struct cmsghdr *cmsg; - uint16_t *gsosizeptr; int ret; iov.iov_base = buf; @@ -237,8 +236,7 @@ static int recv_msg(int fd, char *buf, int len, int *gso_size) cmsg = CMSG_NXTHDR(&msg, cmsg)) { if (cmsg->cmsg_level == SOL_UDP && cmsg->cmsg_type == UDP_GRO) { - gsosizeptr = (uint16_t *) CMSG_DATA(cmsg); - *gso_size = *gsosizeptr; + *gso_size = *(int *)CMSG_DATA(cmsg); break; } } -- 2.39.2