diff options
| author | Vasiliy Kulikov <segoon@openwall.com> | 2011-03-15 13:36:05 +0100 |
|---|---|---|
| committer | Patrick McHardy <kaber@trash.net> | 2011-03-15 13:36:05 +0100 |
| commit | 78b79876761b86653df89c48a7010b5cbd41a84a (patch) | |
| tree | 8b2d66a823640ab1a5c7e31d4b27b69bfbb86cde | |
| parent | 42eab94fff18cb1091d3501cd284d6bd6cc9c143 (diff) | |
netfilter: ip_tables: fix infoleak to userspace
Structures ipt_replace, compat_ipt_replace, and xt_get_revision are
copied from userspace. Fields of these structs that are
zero-terminated strings are not checked. When they are used as argument
to a format string containing "%s" in request_module(), some sensitive
information is leaked to userspace via argument of spawned modprobe
process.
The first and the third bugs were introduced before the git epoch; the
second was introduced in 2722971c (v2.6.17-rc1). To trigger the bug
one should have CAP_NET_ADMIN.
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
| -rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index ef7d7b9680e..b09ed0d080f 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1262,6 +1262,7 @@ do_replace(struct net *net, const void __user *user, unsigned int len) /* overflow check */ if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; + tmp.name[sizeof(tmp.name)-1] = 0; newinfo = xt_alloc_table_info(tmp.size); if (!newinfo) @@ -1807,6 +1808,7 @@ compat_do_replace(struct net *net, void __user *user, unsigned int len) return -ENOMEM; if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; + tmp.name[sizeof(tmp.name)-1] = 0; newinfo = xt_alloc_table_info(tmp.size); if (!newinfo) @@ -2036,6 +2038,7 @@ do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) ret = -EFAULT; break; } + rev.name[sizeof(rev.name)-1] = 0; if (cmd == IPT_SO_GET_REVISION_TARGET) target = 1; |