Commit d6367d62 authored by NeilBrown's avatar NeilBrown Committed by Jeff Layton
Browse files

fs/locks: use properly initialized file_lock when unlocking. 



Both locks_remove_posix() and locks_remove_flock() use a
struct file_lock without calling locks_init_lock() on it.
This means the various list_heads are not initialized, which
will become a problem with a later patch.

So change them both to initialize properly.  For flock locks,
this involves using flock_make_lock(), and changing it to
allow a file_lock to be passed in, so memory allocation isn't
always needed.

Signed-off-by: default avatarNeilBrown <neilb@suse.com>
Reviewed-by: default avatarJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: default avatarJeff Layton <jlayton@kernel.org>
parent 4316c3c6

fs/locks.c

+14 −14
Original line number Diff line number Diff line
@@ -418,17 +418,20 @@ static inline int flock_translate_cmd(int cmd) { 


/* Fill in a file_lock structure with an appropriate FLOCK lock. */

static struct file_lock *

flock_make_lock(struct file *filp, unsigned int cmd)

flock_make_lock(struct file *filp, unsigned int cmd, struct file_lock *fl)

{

	struct file_lock *fl;

	int type = flock_translate_cmd(cmd);



	if (type < 0)

		return ERR_PTR(type);

	

	if (fl == NULL) {

		fl = locks_alloc_lock();

		if (fl == NULL)

			return ERR_PTR(-ENOMEM);

	} else {

		locks_init_lock(fl);

	}



	fl->fl_file = filp;

	fl->fl_owner = filp;
@@ -2009,7 +2012,7 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd) 
	    !(f.file->f_mode & (FMODE_READ|FMODE_WRITE)))

		goto out_putf;



	lock = flock_make_lock(f.file, cmd);

	lock = flock_make_lock(f.file, cmd, NULL);

	if (IS_ERR(lock)) {

		error = PTR_ERR(lock);

		goto out_putf;
@@ -2484,6 +2487,7 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner) 
	if (!ctx || list_empty(&ctx->flc_posix))

		return;



	locks_init_lock(&lock);

	lock.fl_type = F_UNLCK;

	lock.fl_flags = FL_POSIX | FL_CLOSE;

	lock.fl_start = 0;
@@ -2507,19 +2511,15 @@ EXPORT_SYMBOL(locks_remove_posix); 
static void

locks_remove_flock(struct file *filp, struct file_lock_context *flctx)

{

	struct file_lock fl = {

		.fl_owner = filp,

		.fl_pid = current->tgid,

		.fl_file = filp,

		.fl_flags = FL_FLOCK | FL_CLOSE,

		.fl_type = F_UNLCK,

		.fl_end = OFFSET_MAX,

	};

	struct file_lock fl;

	struct inode *inode = locks_inode(filp);



	if (list_empty(&flctx->flc_flock))

		return;



	flock_make_lock(filp, LOCK_UN, &fl);

	fl.fl_flags |= FL_CLOSE;



	if (filp->f_op->flock)

		filp->f_op->flock(filp, F_SETLKW, &fl);

	else

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