Commit 45df9111 authored by John Groves's avatar John Groves Committed by Ira Weiny
Browse files

dax/fsdev: fix uninitialized kaddr in fsdev_dax_zero_page_range() 



__fsdev_dax_direct_access() returns -EFAULT without setting *kaddr when
dax_pgoff_to_phys() returns -1 (pgoff out of range). The return value
was ignored, leaving kaddr uninitialized before being passed to
fsdev_write_dax().

Check the return value and propagate the error.

Thanks to Dan Carpenter and the smatch project for reporting this.

Signed-off-by: default avatarJohn Groves <john@groves.net>
Reviewed-by: default avatarJonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: default avatarDave Jiang <dave.jiang@intel.com>
Link: https://patch.msgid.link/0100019d8262cda2-9714d31c-8fc1-4ca5-b32d-4df678240d14-000000@email.amazonses.com


Signed-off-by: default avatarIra Weiny <ira.weiny@intel.com>
parent 2ae624d5

drivers/dax/fsdev.c

+4 −1
Original line number Diff line number Diff line
@@ -80,9 +80,12 @@ static int fsdev_dax_zero_page_range(struct dax_device *dax_dev, 
			pgoff_t pgoff, size_t nr_pages)

{

	void *kaddr;

	long rc;



	WARN_ONCE(nr_pages > 1, "%s: nr_pages > 1\n", __func__);

	__fsdev_dax_direct_access(dax_dev, pgoff, 1, DAX_ACCESS, &kaddr, NULL);

	rc = __fsdev_dax_direct_access(dax_dev, pgoff, 1, DAX_ACCESS, &kaddr, NULL);

	if (rc < 0)

		return rc;

	fsdev_write_dax(kaddr, ZERO_PAGE(0), 0, PAGE_SIZE);

	return 0;

}