From f9eb4baabdc882b44f2229272516bd8a7f892db2 Mon Sep 17 00:00:00 2001 From: "D. Wythe" Date: Fri, 3 Nov 2023 14:07:39 +0800 Subject: [PATCH] net/smc: allow cdc msg send rather than drop it with NULL sndbuf_desc [ Upstream commit c5bf605ba4f9d6fbbb120595ab95002f4716edcb ] This patch re-fix the issues mentioned 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 allows 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 Reviewed-by: Dust Li Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- 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 01bdb7909a14..3c06625ceb20 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++;