netdev - [PATCH net 2/3] net/smc: allow cdc msg send rather than drop it with NULL sndbuf

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1698810177-69740-3-git-send-email-alibuda@linux.alibaba.com>
Date: Wed,  1 Nov 2023 11:42:56 +0800
From: "D. Wythe" <alibuda@...ux.alibaba.com>
To: kgraul@...ux.ibm.com,
	wenjia@...ux.ibm.com,
	jaka@...ux.ibm.com,
	wintera@...ux.ibm.com
Cc: kuba@...nel.org,
	davem@...emloft.net,
	netdev@...r.kernel.org,
	linux-s390@...r.kernel.org,
	linux-rdma@...r.kernel.org
Subject: [PATCH net 2/3] net/smc: allow cdc msg send rather than drop it with NULL sndbuf_desc

From: "D. Wythe" <alibuda@...ux.alibaba.com>

This patch re-fix the issues memtianed by commit 22a825c541d7
("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()").

Blocking sending message do solve the issues though, but it also
prevents the peer to receive the final message. Besides, in logic,
whether the sndbuf_desc is NULL or not have no impact on the processing
of cdc message sending.

Hence that, this patch allow the cdc message sending but to check the
sndbuf_desc with care in smc_cdc_tx_handler().

Fixes: 22a825c541d7 ("net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()")
Signed-off-by: D. Wythe <alibuda@...ux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@...ux.ibm.com>
---
 net/smc/smc_cdc.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/net/smc/smc_cdc.c b/net/smc/smc_cdc.c
index 01bdb79..3c06625 100644
--- a/net/smc/smc_cdc.c
+++ b/net/smc/smc_cdc.c
@@ -28,13 +28,15 @@ static void smc_cdc_tx_handler(struct smc_wr_tx_pend_priv *pnd_snd,
 {
 	struct smc_cdc_tx_pend *cdcpend = (struct smc_cdc_tx_pend *)pnd_snd;
 	struct smc_connection *conn = cdcpend->conn;
+	struct smc_buf_desc *sndbuf_desc;
 	struct smc_sock *smc;
 	int diff;
 
+	sndbuf_desc = conn->sndbuf_desc;
 	smc = container_of(conn, struct smc_sock, conn);
 	bh_lock_sock(&smc->sk);
-	if (!wc_status) {
-		diff = smc_curs_diff(cdcpend->conn->sndbuf_desc->len,
+	if (!wc_status && sndbuf_desc) {
+		diff = smc_curs_diff(sndbuf_desc->len,
 				     &cdcpend->conn->tx_curs_fin,
 				     &cdcpend->cursor);
 		/* sndbuf_space is decreased in smc_sendmsg */
@@ -114,9 +116,6 @@ int smc_cdc_msg_send(struct smc_connection *conn,
 	union smc_host_cursor cfed;
 	int rc;
 
-	if (unlikely(!READ_ONCE(conn->sndbuf_desc)))
-		return -ENOBUFS;
-
 	smc_cdc_add_pending_send(conn, pend);
 
 	conn->tx_cdc_seq++;
-- 
1.8.3.1