Commit 76b57e61 authored by Jiri Slaby's avatar Jiri Slaby Committed by Rafael J. Wysocki
Browse files

PM / Hibernate: Fix blkdev refleaks 



While cruising through the swsusp code I found few blkdev reference
leaks of resume_bdev.

swsusp_read: remove blkdev_put altogether. Some fail paths do
             not do that.
swsusp_check: make sure we always put a reference on fail paths
software_resume: all fail paths between swsusp_check and swsusp_read
                 omit swsusp_close. Add it in those cases. And since
                 swsusp_read doesn't drop the reference anymore, do
                 it here unconditionally.

[rjw: Fixed a small coding style issue.]

Signed-off-by: default avatarJiri Slaby <jirislaby@gmail.com>
Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
parent 9905d1b4

kernel/power/hibernate.c

+8 −3
Original line number Diff line number Diff line
@@ -693,21 +693,22 @@ static int software_resume(void) 
	/* The snapshot device should not be opened while we're running */

	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {

		error = -EBUSY;

		swsusp_close(FMODE_READ);

		goto Unlock;

	}



	pm_prepare_console();

	error = pm_notifier_call_chain(PM_RESTORE_PREPARE);

	if (error)

		goto Finish;

		goto close_finish;



	error = usermodehelper_disable();

	if (error)

		goto Finish;

		goto close_finish;



	error = create_basic_memory_bitmaps();

	if (error)

		goto Finish;

		goto close_finish;



	pr_debug("PM: Preparing processes for restore.\n");

	error = prepare_processes();
@@ -719,6 +720,7 @@ static int software_resume(void) 
	pr_debug("PM: Reading hibernation image.\n");



	error = swsusp_read(&flags);

	swsusp_close(FMODE_READ);

	if (!error)

		hibernation_restore(flags & SF_PLATFORM_MODE);
@@ -737,6 +739,9 @@ static int software_resume(void) 
	mutex_unlock(&pm_mutex);

	pr_debug("PM: Resume from disk failed.\n");

	return error;

close_finish:

	swsusp_close(FMODE_READ);

	goto Finish;

}



late_initcall(software_resume);

kernel/power/swap.c

+4 −4
Original line number Diff line number Diff line
@@ -572,8 +572,6 @@ int swsusp_read(unsigned int *flags_p) 
		error = load_image(&handle, &snapshot, header->pages - 1);

	release_swap_reader(&handle);



	blkdev_put(resume_bdev, FMODE_READ);



	if (!error)

		pr_debug("PM: Image successfully loaded\n");

	else
@@ -596,7 +594,7 @@ int swsusp_check(void) 
		error = bio_read_page(swsusp_resume_block,

					swsusp_header, NULL);

		if (error)

			return error;

			goto put;



		if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) {

			memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
@@ -604,8 +602,10 @@ int swsusp_check(void) 
			error = bio_write_page(swsusp_resume_block,

						swsusp_header, NULL);

		} else {

			return -EINVAL;

			error = -EINVAL;

		}



put:

		if (error)

			blkdev_put(resume_bdev, FMODE_READ);

		else

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