diff options
author | Vasiliy Kulikov <segoon@openwall.com> | 2011-03-20 15:42:52 +0100 |
---|---|---|
committer | Andi Kleen <ak@linux.intel.com> | 2011-04-28 08:20:57 -0700 |
commit | 9c09bd6e205093f8344028671260efd1687f26b9 (patch) | |
tree | 33653036a6728384625e2f98f43cd466d5b22a07 /net | |
parent | d52f8b882ab7a4c44dc04b7195266c75e236b4f0 (diff) |
netfilter: ipt_CLUSTERIP: fix buffer overflow
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 <segoon@openwall.com>
Acked-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Diffstat (limited to 'net')
-rw-r--r-- | net/ipv4/netfilter/ipt_CLUSTERIP.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/ipv4/netfilter/ipt_CLUSTERIP.c b/net/ipv4/netfilter/ipt_CLUSTERIP.c index f91c94b9a79..de773016cbe 100644 --- a/net/ipv4/netfilter/ipt_CLUSTERIP.c +++ b/net/ipv4/netfilter/ipt_CLUSTERIP.c @@ -663,8 +663,11 @@ static ssize_t clusterip_proc_write(struct file *file, const char __user *input, char buffer[PROC_WRITELEN+1]; 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); |