[NETFILTER]: recent match: fix "sleeping function called from invalid context"

create_proc_entry must not be called with locks held. Use a mutex
instead to protect data only changed in user context.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 5 deletions

diff --git a/net/ipv4/netfilter/ipt_recent.c b/net/ipv4/netfilter/ipt_recent.c
index 9686c4d2057d..9b09e481957d 100644
--- a/net/ipv4/netfilter/ipt_recent.c
+++ b/net/ipv4/netfilter/ipt_recent.c
@@ -69,6 +69,7 @@ struct recent_table {
 
 static LIST_HEAD(tables);
 static DEFINE_SPINLOCK(recent_lock);
+static DEFINE_MUTEX(recent_mutex);
 
 #ifdef CONFIG_PROC_FS
 static struct proc_dir_entry    *proc_dir;
@@ -249,7 +250,7 @@ ipt_recent_checkentry(const char *tablename, const void *ip,
             strnlen(info->name, IPT_RECENT_NAME_LEN) == IPT_RECENT_NAME_LEN)
                 return 0;
 
-        spin_lock_bh(&recent_lock);
+        mutex_lock(&recent_mutex);
         t = recent_table_lookup(info->name);
         if (t != NULL) {
                 t->refcnt++;
@@ -258,7 +259,7 @@ ipt_recent_checkentry(const char *tablename, const void *ip,
         }
 
         t = kzalloc(sizeof(*t) + sizeof(t->iphash[0]) * ip_list_hash_size,
-                    GFP_ATOMIC);
+                    GFP_KERNEL);
         if (t == NULL)
                 goto out;
         strcpy(t->name, info->name);
@@ -274,10 +275,12 @@ ipt_recent_checkentry(const char *tablename, const void *ip,
         t->proc->proc_fops = &recent_fops;
         t->proc->data      = t;
 #endif
+        spin_lock_bh(&recent_lock);
         list_add_tail(&t->list, &tables);
+        spin_unlock_bh(&recent_lock);
         ret = 1;
 out:
-        spin_unlock_bh(&recent_lock);
+        mutex_unlock(&recent_mutex);
         return ret;
 }
 
@@ -288,17 +291,19 @@ ipt_recent_destroy(const struct xt_match *match, void *matchinfo,
         const struct ipt_recent_info *info = matchinfo;
         struct recent_table *t;
 
-        spin_lock_bh(&recent_lock);
+        mutex_lock(&recent_mutex);
         t = recent_table_lookup(info->name);
         if (--t->refcnt == 0) {
+                spin_lock_bh(&recent_lock);
                 list_del(&t->list);
+                spin_unlock_bh(&recent_lock);
                 recent_table_flush(t);
 #ifdef CONFIG_PROC_FS
                 remove_proc_entry(t->name, proc_dir);
 #endif
                 kfree(t);
         }
-        spin_unlock_bh(&recent_lock);
+        mutex_unlock(&recent_mutex);
 }
 
 #ifdef CONFIG_PROC_FS