[PATCH 09/17] mm/nommu: switch do_mmap_private to kernel_read

From: Christoph Hellwig
Date: Fri Sep 01 2017 - 11:40:10 EST


Instead of playing with the address limit. This also gains us
validation of the kvec and proper atime updates.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
mm/nommu.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/mm/nommu.c b/mm/nommu.c
index fc184f597d59..e907a25ec9bd 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1164,17 +1164,12 @@ static int do_mmap_private(struct vm_area_struct *vma,

if (vma->vm_file) {
/* read the contents of a file into the copy */
- mm_segment_t old_fs;
loff_t fpos;

fpos = vma->vm_pgoff;
fpos <<= PAGE_SHIFT;

- old_fs = get_fs();
- set_fs(KERNEL_DS);
- ret = __vfs_read(vma->vm_file, base, len, &fpos);
- set_fs(old_fs);
-
+ ret = kernel_read(vma->vm_file, base, len, &fpos);
if (ret < 0)
goto error_free;

--
2.11.0