ipv6: release dst in ping_v6_sendmsg

Neither the failure or success paths of ping_v6_sendmsg release
the dst it acquires.  This leads to a flood of warnings from
"net/core/dst.c:288 dst_release" on older kernels that
don't have 8bf4ada2e2 backported.

That patch optimistically hoped this had been fixed post 3.10, but
it seems at least one case wasn't, where I've seen this triggered
a lot from machines doing unprivileged icmp sockets.

Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Dave Jones <davej@codemonkey.org.uk>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Dave Jones 2016-09-02 14:39:50 -04:00 committed by David S. Miller
parent 6e1ce3c345
commit 03c2778a93

View File

@ -126,8 +126,10 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
rt = (struct rt6_info *) dst;
np = inet6_sk(sk);
if (!np)
return -EBADF;
if (!np) {
err = -EBADF;
goto dst_err_out;
}
if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
fl6.flowi6_oif = np->mcast_oif;
@ -163,6 +165,9 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
}
release_sock(sk);
dst_err_out:
dst_release(dst);
if (err)
return err;