[lkml]   [2011]   [Apr]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[43/71] netfilter: ipt_CLUSTERIP: fix buffer overflow
2.6.33-longterm review patch.  If anyone has any objections, please let us know.


From: Vasiliy Kulikov <>

commit 961ed183a9fd080cf306c659b8736007e44065a5 upstream.

'buffer' string is copied from userspace. It is not checked whether it is
zero terminated. This may lead to overflow inside of simple_strtoul().
Changli Gao suggested to copy not more than user supplied 'size' bytes.

It was introduced before the git epoch. Files "ipt_CLUSTERIP/*" are
root writable only by default, however, on some setups permissions might be
relaxed to e.g. network admin user.

Signed-off-by: Vasiliy Kulikov <>
Acked-by: Changli Gao <>
Signed-off-by: Patrick McHardy <>
Signed-off-by: Greg Kroah-Hartman <>

net/ipv4/netfilter/ipt_CLUSTERIP.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- a/net/ipv4/netfilter/ipt_CLUSTERIP.c
+++ b/net/ipv4/netfilter/ipt_CLUSTERIP.c
@@ -666,8 +666,11 @@ static ssize_t clusterip_proc_write(stru
struct clusterip_config *c = pde->data;
unsigned long nodenum;

- if (copy_from_user(buffer, input, PROC_WRITELEN))
+ if (size > PROC_WRITELEN)
+ return -EIO;
+ if (copy_from_user(buffer, input, size))
return -EFAULT;
+ buffer[size] = 0;

if (*buffer == '+') {
nodenum = simple_strtoul(buffer+1, NULL, 10);

 \ /
  Last update: 2011-04-13 18:25    [W:0.217 / U:1.228 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site