Commit 75dff55a authored by Trond Myklebust's avatar Trond Myklebust Committed by Linus Torvalds
Browse files

[PATCH] fs/locks.c: Fix lease_init 



It is insane to be giving lease_init() the task of freeing the lock it is
supposed to initialise, given that the lock is not guaranteed to be
allocated on the stack. This causes lockups in fcntl_setlease().
Problem diagnosed by Daniel Hokka Zakrisson <daniel@hozac.com>

Also fix a slab leak in __setlease() due to an uninitialised return value.
Problem diagnosed by Björn Steinbrink.

Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: default avatarDaniel Hokka Zakrisson <daniel@hozac.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 9d21f09c

fs/locks.c

+12 −9
Original line number Diff line number Diff line
@@ -446,15 +446,14 @@ static struct lock_manager_operations lease_manager_ops = { 
 */

static int lease_init(struct file *filp, int type, struct file_lock *fl)

 {

	if (assign_type(fl, type) != 0)

		return -EINVAL;



	fl->fl_owner = current->files;

	fl->fl_pid = current->tgid;



	fl->fl_file = filp;

	fl->fl_flags = FL_LEASE;

	if (assign_type(fl, type) != 0) {

		locks_free_lock(fl);

		return -EINVAL;

	}

	fl->fl_start = 0;

	fl->fl_end = OFFSET_MAX;

	fl->fl_ops = NULL;
@@ -466,16 +465,19 @@ static int lease_init(struct file *filp, int type, struct file_lock *fl) 
static int lease_alloc(struct file *filp, int type, struct file_lock **flp)

{

	struct file_lock *fl = locks_alloc_lock();

	int error;

	int error = -ENOMEM;



	if (fl == NULL)

		return -ENOMEM;

		goto out;



	error = lease_init(filp, type, fl);

	if (error)

		return error;

	if (error) {

		locks_free_lock(fl);

		fl = NULL;

	}

out:

	*flp = fl;

	return 0;

	return error;

}



/* Check if two locks overlap each other.
@@ -1372,6 +1374,7 @@ static int __setlease(struct file *filp, long arg, struct file_lock **flp) 
		goto out;



	if (my_before != NULL) {

		*flp = *my_before;

		error = lease->fl_lmops->fl_change(my_before, arg);

		goto out;

	}

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