iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[NET]: NULL pointer dereference and other nasty things in /proc/net/(tcp|udp)[6]

Browse Source 
Commits f40c81 ([NETNS][IPV4] tcp - make proc handle the network
namespaces) and a91275 ([NETNS][IPV6] udp - make proc handle the
network namespace) both introduced bad checks on sockets and tw
buckets to belong to proper net namespace.

I.e. when checking for socket to belong to given net and family the

	do {
		sk = sk_next(sk);
	} while (sk && sk->sk_net != net && sk->sk_family != family);

constructions were used. This is wrong, since as soon as the
sk->sk_net fits the net the socket is immediately returned, even if it
belongs to other family.

As the result four /proc/net/(udp|tcp)[6] entries show wrong info.
The udp6 entry even oopses when dereferencing inet6_sk(sk) pointer:

static void udp6_sock_seq_show(struct seq_file *seq, struct sock *sp, int bucket)
{
	...
        struct ipv6_pinfo *np = inet6_sk(sp);
	...

        dest  = &np->daddr; /* will be NULL for AF_INET sockets */
	...
	seq_printf(...
	           dest->s6_addr32[0], dest->s6_addr32[1],
                   dest->s6_addr32[2], dest->s6_addr32[3],
	...

Fix it by converting && to ||.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Pavel Emelyanov 2008-03-21 15:52:00 -07:00 committed by David S. Miller
parent b1153f29ee
commit 28518fc170
2 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
net/ipv4/tcp_ipv4.c
View File

@ -2050,7 +2050,7 @@ static void *established_get_first(struct seq_file *seq)
st->state = TCP_SEQ_STATE_TIME_WAIT;
inet_twsk_for_each(tw, node,
&tcp_hashinfo.ehash[st->bucket].twchain) {
if (tw->tw_family != st->family &&
if (tw->tw_family != st->family ||
tw->tw_net != net) {
continue;
}
@ -2078,7 +2078,7 @@ static void *established_get_next(struct seq_file *seq, void *cur)
tw = cur;
tw = tw_next(tw);
get_tw:
while (tw && tw->tw_family != st->family && tw->tw_net != net) {
while (tw && (tw->tw_family != st->family || tw->tw_net != net)) {
tw = tw_next(tw);
}
if (tw) {

2
net/ipv4/udp.c
View File

@ -1537,7 +1537,7 @@ static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk)
sk = sk_next(sk);
try_again:
;
} while (sk && sk->sk_net != net && sk->sk_family != state->family);
} while (sk && (sk->sk_net != net || sk->sk_family != state->family));
if (!sk && ++state->bucket < UDP_HTABLE_SIZE) {
sk = sk_head(state->hashtable + state->bucket);