From: Oliver Hartkopp socketcan@hartkopp.net
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=...
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[ 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 derekrobertwill@gmail.com Suggested-by: Derek Will derekrobertwill@gmail.com Tested-by: Derek Will derekrobertwill@gmail.com Signed-off-by: Oliver Hartkopp socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yu Liao liaoyu15@huawei.com Reviewed-by: Wei Li liwei391@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- 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)