Messages in this thread Patch in this message | | | Date | Wed, 13 Apr 2011 08:51:06 -0700 | From | Greg KH <> | Subject | [42/74] netfilter: arp_tables: fix infoleak to userspace |
| |
2.6.32-longterm review patch. If anyone has any objections, please let us know.
------------------
From: Vasiliy Kulikov <segoon@openwall.com>
commit 42eab94fff18cb1091d3501cd284d6bd6cc9c143 upstream.
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: Greg Kroah-Hartman <gregkh@suse.de>
--- net/ipv4/netfilter/arp_tables.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -1086,6 +1086,7 @@ static int do_replace(struct net *net, v /* 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) @@ -1508,6 +1509,7 @@ static int compat_do_replace(struct net 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) @@ -1763,6 +1765,7 @@ static int do_arpt_get_ctl(struct sock * ret = -EFAULT; break; } + rev.name[sizeof(rev.name)-1] = 0; try_then_request_module(xt_find_revision(NFPROTO_ARP, rev.name, rev.revision, 1, &ret),
| |