locks: fix setlease methods to free passed-in lock

[cascardo/linux.git] / fs / locks.c

diff --git a/fs/locks.c b/fs/locks.c
index 50ec159..5b526a9 100644 (file)
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -186,7 +186,7 @@ void locks_release_private(struct file_lock *fl)
 EXPORT_SYMBOL_GPL(locks_release_private);
 
 /* Free a lock which is not in use. */
-static void locks_free_lock(struct file_lock *fl)
+void locks_free_lock(struct file_lock *fl)
 {
        BUG_ON(waitqueue_active(&fl->fl_wait));
        BUG_ON(!list_empty(&fl->fl_block));
@@ -195,6 +195,7 @@ static void locks_free_lock(struct file_lock *fl)
        locks_release_private(fl);
        kmem_cache_free(filelock_cache, fl);
 }
+EXPORT_SYMBOL(locks_free_lock);
 
 void locks_init_lock(struct file_lock *fl)
 {
@@ -1371,20 +1372,22 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
        struct inode *inode = dentry->d_inode;
        int error, rdlease_count = 0, wrlease_count = 0;
 
+       lease = *flp;
+
+       error = -EACCES;
        if ((current_fsuid() != inode->i_uid) && !capable(CAP_LEASE))
-               return -EACCES;
+               goto out;
+       error = -EINVAL;
        if (!S_ISREG(inode->i_mode))
-               return -EINVAL;
+               goto out;
        error = security_file_lock(filp, arg);
        if (error)
-               return error;
+               goto out;
 
        time_out_leases(inode);
 
        BUG_ON(!(*flp)->fl_lmops->fl_break);
 
-       lease = *flp;
-
        if (arg != F_UNLCK) {
                error = -EAGAIN;
                if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
@@ -1441,7 +1444,8 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
        return 0;
 
 out:
-       locks_free_lock(lease);
+       if (arg != F_UNLCK)
+               locks_free_lock(lease);
        return error;
 }
 EXPORT_SYMBOL(generic_setlease);
@@ -1493,17 +1497,16 @@ int vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
 }
 EXPORT_SYMBOL_GPL(vfs_setlease);
 
-/**
- *     fcntl_setlease  -       sets a lease on an open file
- *     @fd: open file descriptor
- *     @filp: file pointer
- *     @arg: type of lease to obtain
- *
- *     Call this fcntl to establish a lease on the file.
- *     Note that you also need to call %F_SETSIG to
- *     receive a signal when the lease is broken.
- */
-int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
+static int do_fcntl_delete_lease(struct file *filp)
+{
+       struct file_lock fl, *flp = &fl;
+
+       lease_init(filp, F_UNLCK, flp);
+
+       return vfs_setlease(filp, F_UNLCK, &flp);
+}
+
+static int do_fcntl_add_lease(unsigned int fd, struct file *filp, long arg)
 {
        struct file_lock *fl;
        struct fasync_struct *new;
@@ -1521,7 +1524,7 @@ int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
        }
        lock_flocks();
        error = __vfs_setlease(filp, arg, &fl);
-       if (error || arg == F_UNLCK)
+       if (error)
                goto out_unlock;
 
        /*
@@ -1549,6 +1552,23 @@ out_unlock:
        return error;
 }
 
+/**
+ *     fcntl_setlease  -       sets a lease on an open file
+ *     @fd: open file descriptor
+ *     @filp: file pointer
+ *     @arg: type of lease to obtain
+ *
+ *     Call this fcntl to establish a lease on the file.
+ *     Note that you also need to call %F_SETSIG to
+ *     receive a signal when the lease is broken.
+ */
+int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
+{
+       if (arg == F_UNLCK)
+               return do_fcntl_delete_lease(filp);
+       return do_fcntl_add_lease(fd, filp, arg);
+}
+
 /**
  * flock_lock_file_wait - Apply a FLOCK-style lock to a file
  * @filp: The file to apply the lock to