From d1aadbc634287185ce09612a9be266eac1d16654 Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Mon, 28 Mar 2022 13:36:11 +0200 Subject: [PATCH] can: isotp: restore accidentally removed MSG_PEEK feature In commit de1d3e5dc93d ("can: isotp: support MSG_TRUNC flag when reading from socket") a new check for recvmsg flags has been introduced that only checked for the flags that are handled in isotp_recvmsg() itself. This accidentally removed the MSG_PEEK feature flag which is processed later in the call chain in __skb_try_recv_from_queue(). Add MSG_PEEK to the set of valid flags to restore the feature. Fixes: de1d3e5dc93d ("can: isotp: support MSG_TRUNC flag when reading from socket") Link: https://github.com/linux-can/can-utils/issues/347#issuecomment-1079554254 Link: https://lore.kernel.org/all/20220328113611.3691-1-socketcan@hartkopp.net Reported-by: Derek Will Suggested-by: Derek Will Tested-by: Derek Will Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- net/can/isotp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/can/isotp.c b/net/can/isotp.c index f6f8ba1f816d4..bafb0fb5f0e0e 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -1050,7 +1050,7 @@ static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, int noblock = flags & MSG_DONTWAIT; int ret = 0; - if (flags & ~(MSG_DONTWAIT | MSG_TRUNC)) + if (flags & ~(MSG_DONTWAIT | MSG_TRUNC | MSG_PEEK)) return -EINVAL; if (!so->bound) -- 2.39.5