fcntl: fix potential deadlock for &fasync_struct.fa_lock

[linux-2.6-block.git] / fs / fcntl.c

diff --git a/fs/fcntl.c b/fs/fcntl.c
index 932ec1e9f5bfc173a8f2fb3516318bf9ea76976a..68added37c15fe769d5dc95dc1190229651ecb24 100644 (file)
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -1004,13 +1004,14 @@ static void kill_fasync_rcu(struct fasync_struct *fa, int sig, int band)
 {
        while (fa) {
                struct fown_struct *fown;
+               unsigned long flags;
 
                if (fa->magic != FASYNC_MAGIC) {
                        printk(KERN_ERR "kill_fasync: bad magic number in "
                               "fasync_struct!\n");
                        return;
                }
-               read_lock(&fa->fa_lock);
+               read_lock_irqsave(&fa->fa_lock, flags);
                if (fa->fa_file) {
                        fown = &fa->fa_file->f_owner;
                        /* Don't send SIGURG to processes which have not set a
@@ -1019,7 +1020,7 @@ static void kill_fasync_rcu(struct fasync_struct *fa, int sig, int band)
                        if (!(sig == SIGURG && fown->signum == 0))
                                send_sigio(fown, fa->fa_fd, band);
                }
-               read_unlock(&fa->fa_lock);
+               read_unlock_irqrestore(&fa->fa_lock, flags);
                fa = rcu_dereference(fa->fa_next);
        }
 }