From 9c9c53c5ef6ded65dfc624e3962d5e15f8cfd4c6 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Fri, 7 Nov 2014 21:27:08 +0800 Subject: [PATCH] ipv4: Use standard iovec primitive in raw_probe_proto_opt commit 32b5913a931fd753faf3d4e1124b2bc2edb364da upstream. The function raw_probe_proto_opt tries to extract the first two bytes from the user input in order to seed the IPsec lookup for ICMP packets. In doing so it's processing iovec by hand and overcomplicating things. This patch replaces the manual iovec processing with a call to memcpy_fromiovecend. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/ipv4/raw.c | 50 +++++++++++--------------------------------------- 1 file changed, 11 insertions(+), 39 deletions(-) diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index e6430963e994..5679ba7b8da0 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -411,48 +411,20 @@ error: static int raw_probe_proto_opt(struct flowi4 *fl4, struct msghdr *msg) { - struct iovec *iov; - u8 __user *type = NULL; - u8 __user *code = NULL; - int probed = 0; - unsigned int i; + struct icmphdr icmph; + int err; - if (!msg->msg_iov) + if (fl4->flowi4_proto != IPPROTO_ICMP) return 0; - for (i = 0; i < msg->msg_iovlen; i++) { - iov = &msg->msg_iov[i]; - if (!iov) - continue; - - switch (fl4->flowi4_proto) { - case IPPROTO_ICMP: - /* check if one-byte field is readable or not. */ - if (iov->iov_base && iov->iov_len < 1) - break; - - if (!type) { - type = iov->iov_base; - /* check if code field is readable or not. */ - if (iov->iov_len > 1) - code = type + 1; - } else if (!code) - code = iov->iov_base; - - if (type && code) { - if (get_user(fl4->fl4_icmp_type, type) || - get_user(fl4->fl4_icmp_code, code)) - return -EFAULT; - probed = 1; - } - break; - default: - probed = 1; - break; - } - if (probed) - break; - } + /* We only need the first two bytes. */ + err = memcpy_fromiovecend((void *)&icmph, msg->msg_iov, 0, 2); + if (err) + return err; + + fl4->fl4_icmp_type = icmph.type; + fl4->fl4_icmp_code = icmph.code; + return 0; } -- 2.39.2