From: Kuniyuki Iwashima kuniyu@amazon.com
[ Upstream commit d9ba9934285514f1f95d96326a82398a22dc77f2 ]
Paul Holzinger reported [0] that commit 5456262d2baa ("net: Fix incorrect address comparison when searching for a bind2 bucket") introduced a bind() regression. Paul also gave a nice repro that calls two types of bind() on the same port, both of which now succeed, but the second call should fail:
bind(fd1, ::, port) + bind(fd2, 127.0.0.1, port)
The cited commit added address family tests in three functions to fix the uninit-value KMSAN report. [1] However, the test added to inet_bind2_bucket_match_addr_any() removed a necessary conflict check; the dual-stack wildcard address no longer conflicts with an IPv4 non-wildcard address.
If tb->family is AF_INET6 and sk->sk_family is AF_INET in inet_bind2_bucket_match_addr_any(), we still need to check if tb has the dual-stack wildcard address.
Note that the IPv4 wildcard address does not conflict with IPv6 non-wildcard addresses.
[0]: https://lore.kernel.org/netdev/e21bf153-80b0-9ec0-15ba-e04a4ad42c34@redhat.c... [1]: https://lore.kernel.org/netdev/CAG_fn=Ud3zSW7AZWXc+asfMhZVL5ETnvuY44Pmyv4NPv...
Fixes: 5456262d2baa ("net: Fix incorrect address comparison when searching for a bind2 bucket") Signed-off-by: Kuniyuki Iwashima kuniyu@amazon.com Reported-by: Paul Holzinger pholzing@redhat.com Link: https://lore.kernel.org/netdev/CAG_fn=Ud3zSW7AZWXc+asfMhZVL5ETnvuY44Pmyv4NPv... Reviewed-by: Eric Dumazet edumazet@google.com Tested-by: Paul Holzinger pholzing@redhat.com Reviewed-by: Martin KaFai Lau martin.lau@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/inet_hashtables.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index cd8b2f7a8f341..f0750c06d5ffc 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -828,8 +828,14 @@ bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const #if IS_ENABLED(CONFIG_IPV6) struct in6_addr addr_any = {};
- if (sk->sk_family != tb->family) + if (sk->sk_family != tb->family) { + if (sk->sk_family == AF_INET) + return net_eq(ib2_net(tb), net) && tb->port == port && + tb->l3mdev == l3mdev && + ipv6_addr_equal(&tb->v6_rcv_saddr, &addr_any); + return false; + }
if (sk->sk_family == AF_INET6) return net_eq(ib2_net(tb), net) && tb->port == port &&