diff mbox

[03/13] bridge: netfilter: fix information leak

Message ID 1299067973-15977-4-git-send-email-kaber@trash.net
State Accepted, archived
Delegated to: David Miller
Headers show

Commit Message

Patrick McHardy March 2, 2011, 12:12 p.m. UTC 
From: Vasiliy Kulikov <segoon@openwall.com>

Struct tmp is copied from userspace.  It is not checked whether the "name"
field is NULL terminated.  This may lead to buffer overflow and passing
contents of kernel stack as a module name to try_then_request_module() and,
consequently, to modprobe commandline.  It would be seen by all userspace
processes.

Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
 net/bridge/netfilter/ebtables.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
diff mbox

Patch

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 5f1825d..893669c 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1107,6 +1107,8 @@  static int do_replace(struct net *net, const void __user *user,
 	if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter))
 		return -ENOMEM;
 
+	tmp.name[sizeof(tmp.name) - 1] = 0;
+
 	countersize = COUNTER_OFFSET(tmp.nentries) * nr_cpu_ids;
 	newinfo = vmalloc(sizeof(*newinfo) + countersize);
 	if (!newinfo)