| Message ID | 1309796858-2752-1-git-send-email-paolo.pisati@canonical.com |
|---|---|
| State | New |
| Headers | show |
On Mon, Jul 04, 2011 at 05:27:37PM +0100, paolo.pisati@canonical.com wrote: > From: Vasiliy Kulikov <segoon@openwall.com> > > BugLink: http://bugs.launchpad.net/bugs/801480 > > commit upstream 42eab94fff18cb1091d3501cd284d6bd6cc9c143 > > 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 bug was introduced before the git epoch; the second is > introduced by 6b7d31fc (v2.6.15-rc1); the third is introduced by > 6b7d31fc (v2.6.15-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> > Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com> > --- > net/ipv4/netfilter/arp_tables.c | 2 ++ > 1 files changed, 2 insertions(+), 0 deletions(-) > > diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c > index 2909c92..1116949 100644 > --- a/net/ipv4/netfilter/arp_tables.c > +++ b/net/ipv4/netfilter/arp_tables.c > @@ -816,6 +816,7 @@ static int do_replace(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) > @@ -1070,6 +1071,7 @@ static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len > ret = -EFAULT; > break; > } > + rev.name[sizeof(rev.name)-1] = 0; > > try_then_request_module(xt_find_revision(NF_ARP, rev.name, > rev.revision, 1, &ret), Misses one hunk from upstream which applied to a non-existant piece of code. Looks sane. Acked-by: Andy Whitcroft <apw@canonical.com> -apw
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index 2909c92..1116949 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -816,6 +816,7 @@ static int do_replace(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) @@ -1070,6 +1071,7 @@ static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len ret = -EFAULT; break; } + rev.name[sizeof(rev.name)-1] = 0; try_then_request_module(xt_find_revision(NF_ARP, rev.name, rev.revision, 1, &ret),