diff options
author | Arnd Bergmann <arnd@arndb.de> | 2018-02-22 16:55:34 +0100 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2018-02-23 16:53:26 +0100 |
commit | ca79bec237f5809a7c3c59bd41cd0880aa889966 (patch) | |
tree | 6aee670173dfc14aa98df0e775a42dda5d6b0eb0 /net/ipv6 | |
parent | macvlan: fix use-after-free in macvlan_common_newlink() (diff) | |
download | linux-ca79bec237f5809a7c3c59bd41cd0880aa889966.tar.xz linux-ca79bec237f5809a7c3c59bd41cd0880aa889966.zip |
ipv6 sit: work around bogus gcc-8 -Wrestrict warning
gcc-8 has a new warning that detects overlapping input and output arguments
in memcpy(). It triggers for sit_init_net() calling ipip6_tunnel_clone_6rd(),
which is actually correct:
net/ipv6/sit.c: In function 'sit_init_net':
net/ipv6/sit.c:192:3: error: 'memcpy' source argument is the same as destination [-Werror=restrict]
The problem here is that the logic detecting the memcpy() arguments finds them
to be the same, but the conditional that tests for the input and output of
ipip6_tunnel_clone_6rd() to be identical is not a compile-time constant.
We know that netdev_priv(t->dev) is the same as t for a tunnel device,
and comparing "dev" directly here lets the compiler figure out as well
that 'dev == sitn->fb_tunnel_dev' when called from sit_init_net(), so
it no longer warns.
This code is old, so Cc stable to make sure that we don't get the warning
for older kernels built with new gcc.
Cc: Martin Sebor <msebor@gmail.com>
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83456
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
-rw-r--r-- | net/ipv6/sit.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 3873d3877135..3a1775a62973 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -182,7 +182,7 @@ static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn) #ifdef CONFIG_IPV6_SIT_6RD struct ip_tunnel *t = netdev_priv(dev); - if (t->dev == sitn->fb_tunnel_dev) { + if (dev == sitn->fb_tunnel_dev) { ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0); t->ip6rd.relay_prefix = 0; t->ip6rd.prefixlen = 16; |