From e83e57da7fe454d55a9a42a0f8a8b8952088889b Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Tue, 5 Jul 2022 17:51:16 +0800 Subject: [PATCH] can: isotp: restore accidentally removed MSG_PEEK feature stable inclusion from stable-v5.10.110 commit 90ec1b1538d4d5e9f0267ca16d30606b4701da50 bugzilla: https://gitee.com/openeuler/kernel/issues/I574AL Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=90ec1b1538d4d5e9f0267ca16d30606b4701da50 -------------------------------- [ Upstream commit e382fea8ae54f5bb62869c6b69b33993d43adeca ] In commit 42bf50a1795a ("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: 42bf50a1795a ("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 Signed-off-by: Sasha Levin Signed-off-by: Yu Liao Reviewed-by: Wei Li Signed-off-by: Zheng Zengkai --- 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 671c3673b7ea..63e6e8923200 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -1007,7 +1007,7 @@ 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) -- GitLab