netfilter: nf_log: don't hold nf_log_mutex during user access

[linux-2.6-microblaze.git] / net / netfilter / nf_log.c

diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index 4264570..a61d6df 100644 (file)
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -424,6 +424,10 @@ static int nf_log_proc_dostring(struct ctl_table *table, int write,
        if (write) {
                struct ctl_table tmp = *table;
 
+               /* proc_dostring() can append to existing strings, so we need to
+                * initialize it as an empty string.
+                */
+               buf[0] = '\0';
                tmp.data = buf;
                r = proc_dostring(&tmp, write, buffer, lenp, ppos);
                if (r)
@@ -442,14 +446,17 @@ static int nf_log_proc_dostring(struct ctl_table *table, int write,
                rcu_assign_pointer(net->nf.nf_loggers[tindex], logger);
                mutex_unlock(&nf_log_mutex);
        } else {
+               struct ctl_table tmp = *table;
+
+               tmp.data = buf;
                mutex_lock(&nf_log_mutex);
                logger = nft_log_dereference(net->nf.nf_loggers[tindex]);
                if (!logger)
-                       table->data = "NONE";
+                       strlcpy(buf, "NONE", sizeof(buf));
                else
-                       table->data = logger->name;
-               r = proc_dostring(table, write, buffer, lenp, ppos);
+                       strlcpy(buf, logger->name, sizeof(buf));
                mutex_unlock(&nf_log_mutex);
+               r = proc_dostring(&tmp, write, buffer, lenp, ppos);
        }
 
        return r;