4.7-stable review patch. If anyone has any objections, please let me know.
------------------
From: Dave Jones <da...@codemonkey.org.uk>
[ Upstream commit 03c2778a938aaba0893f6d6cdc29511d91a79848 ]
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 8bf4ada2e21378816b28205427ee6b0e1ca4c5f1 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 <ka...@fb.com>
Signed-off-by: Dave Jones <da...@codemonkey.org.uk>
Acked-by: Martin KaFai Lau <ka...@fb.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
net/ipv6/ping.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -122,8 +122,10 @@ static int ping_v6_sendmsg(struct sock *
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;
@@ -160,6 +162,9 @@ static int ping_v6_sendmsg(struct sock *
}
release_sock(sk);
+dst_err_out:
+ dst_release(dst);
+
if (err)
return err;
