Commit 230f5a89 authored Feb 21, 2018 by Dan Williams

dax: fix vma_is_fsdax() helper



Gerd reports that ->i_mode may contain other bits besides S_IFCHR. Use
S_ISCHR() instead. Otherwise, get_user_pages_longterm() may fail on
device-dax instances when those are meant to be explicitly allowed.

Fixes: 2bb6d283 ("mm: introduce get_user_pages_longterm")
Cc: <stable@vger.kernel.org>
Reported-by: Gerd Rausch <gerd.rausch@oracle.com>
Acked-by: Jane Chu <jane.chu@oracle.com>
Reported-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

parent 9d4949b4

include/linux/fs.h

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -3198,7 +3198,7 @@ static inline bool vma_is_fsdax(struct vm_area_struct *vma)
	if (!vma_is_dax(vma))		if (!vma_is_dax(vma))
	return false;		return false;
	inode = file_inode(vma->vm_file);		inode = file_inode(vma->vm_file);
	if (inode->i_mode == S_IFCHR)		if (S_ISCHR(inode->i_mode))
	return false; /* device-dax */		return false; /* device-dax */
	return true;		return true;
	}		}