This is a note to let you know that I've just added the patch titled
net/smc: check return value of sock_recvmsg when draining clc data
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-smc-check-return-value-of-sock_recvmsg-when-drai.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 048ca86e3d803d22a6cce94aff44829608a03820
Author: Guangguan Wang <guangguan.wang@xxxxxxxxxxxxxxxxx>
Date: Wed Dec 11 17:21:21 2024 +0800
net/smc: check return value of sock_recvmsg when draining clc data
[ Upstream commit c5b8ee5022a19464783058dc6042e8eefa34e8cd ]
When receiving clc msg, the field length in smc_clc_msg_hdr indicates the
length of msg should be received from network and the value should not be
fully trusted as it is from the network. Once the value of length exceeds
the value of buflen in function smc_clc_wait_msg it may run into deadloop
when trying to drain the remaining data exceeding buflen.
This patch checks the return value of sock_recvmsg when draining data in
case of deadloop in draining.
Fixes: fb4f79264c0f ("net/smc: tolerate future SMCD versions")
Signed-off-by: Guangguan Wang <guangguan.wang@xxxxxxxxxxxxxxxxx>
Reviewed-by: Wen Gu <guwen@xxxxxxxxxxxxxxxxx>
Reviewed-by: D. Wythe <alibuda@xxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 035e8135ea49..52a0ba939c91 100644
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -427,6 +427,11 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
SMC_CLC_RECV_BUF_LEN : datlen;
iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, recvlen);
len = sock_recvmsg(smc->clcsock, &msg, krflags);
+ if (len < recvlen) {
+ smc->sk.sk_err = EPROTO;
+ reason_code = -EPROTO;
+ goto out;
+ }
datlen -= len;
}
if (clcm->type == SMC_CLC_DECLINE) {
