inet: prevent leakage of uninitialized memory to user in recv syscalls

[firefly-linux-kernel-4.4.55.git] / net / ipv4 / raw.c

diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 6fb233772f793fce6723e5ac50dff701bb972ac2..448e5a77fa88d622cc540d5fb6e06b0a28a5934b 100644 (file)
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -692,9 +692,6 @@ static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
        if (flags & MSG_OOB)
                goto out;
 
-       if (addr_len)
-               *addr_len = sizeof(*sin);
-
        if (flags & MSG_ERRQUEUE) {
                err = ip_recv_error(sk, msg, len);
                goto out;
@@ -722,6 +719,7 @@ static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
                sin->sin_port = 0;
                memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
+               *addr_len = sizeof(*sin);
        }
        if (inet->cmsg_flags)
                ip_cmsg_recv(msg, skb);