ext4: remove the access_ok() check in ext4_ioctl_get_es_cache

access_ok just checks we are fed a proper user pointer.  We also do that
in copy_to_user itself, so no need to do this early.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Ritesh Harjani <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>

Author: Christoph Hellwig

fs/ext4/ioctl.c

@@ -754,11 +754,6 @@ static int ext4_ioctl_get_es_cache(struct file *filp, unsigned long arg)
 	fieinfo.fi_extents_max = fiemap.fm_extent_count;
 	fieinfo.fi_extents_start = ufiemap->fm_extents;
 
-	if (fiemap.fm_extent_count != 0 &&
-	    !access_ok(fieinfo.fi_extents_start,
-		       fieinfo.fi_extents_max * sizeof(struct fiemap_extent)))
-		return -EFAULT;
-
 	error = ext4_get_es_cache(inode, &fieinfo, fiemap.fm_start,
 			fiemap.fm_length);
 	fiemap.fm_flags = fieinfo.fi_flags;