From 249556192859490b6280552d4b877064f9f5ee48 Mon Sep 17 00:00:00 2001
From: Patrick McHardy <kaber@trash.net>
Date: Mon, 22 Jun 2009 14:15:30 +0200
Subject: [PATCH] netfilter: nf_log: fix direct userspace memory access in proc
handler
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
net/netfilter/nf_log.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index 2fefe147750a0..4e620305f28c7 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -47,7 +47,6 @@ int nf_log_register(u_int8_t pf, struct nf_logger *logger)
mutex_lock(&nf_log_mutex);
if (pf == NFPROTO_UNSPEC) {
- int i;
for (i = NFPROTO_UNSPEC; i < NFPROTO_NUMPROTO; i++)
list_add_tail(&(logger->list[i]), &(nf_loggers_l[i]));
} else {
@@ -216,7 +215,7 @@ static const struct file_operations nflog_file_ops = {
#endif /* PROC_FS */
#ifdef CONFIG_SYSCTL
-struct ctl_path nf_log_sysctl_path[] = {
+static struct ctl_path nf_log_sysctl_path[] = {
{ .procname = "net", .ctl_name = CTL_NET, },
{ .procname = "netfilter", .ctl_name = NET_NETFILTER, },
{ .procname = "nf_log", .ctl_name = CTL_UNNUMBERED, },
@@ -228,19 +227,26 @@ static struct ctl_table nf_log_sysctl_table[NFPROTO_NUMPROTO+1];
static struct ctl_table_header *nf_log_dir_header;
static int nf_log_proc_dostring(ctl_table *table, int write, struct file *filp,
- void *buffer, size_t *lenp, loff_t *ppos)
+ void __user *buffer, size_t *lenp, loff_t *ppos)
{
const struct nf_logger *logger;
+ char buf[NFLOGGER_NAME_LEN];
+ size_t size = *lenp;
int r = 0;
int tindex = (unsigned long)table->extra1;
if (write) {
- if (!strcmp(buffer, "NONE")) {
+ if (size > sizeof(buf))
+ size = sizeof(buf);
+ if (copy_from_user(buf, buffer, size))
+ return -EFAULT;
+
+ if (!strcmp(buf, "NONE")) {
nf_log_unbind_pf(tindex);
return 0;
}
mutex_lock(&nf_log_mutex);
- logger = __find_logger(tindex, buffer);
+ logger = __find_logger(tindex, buf);
if (logger == NULL) {
mutex_unlock(&nf_log_mutex);
return -ENOENT;
--
2.30.2