hugetlb: unsigned ret cannot be negative

unsigned long ret cannot be negative, but ret can get -EFAULT.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Ken Chen <kenchen@google.com>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 4 deletions

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 0ab0c6f5f438..6903d37af037 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -252,6 +252,7 @@ static ssize_t hugetlbfs_read(struct file *filp, char __user *buf,
         for (;;) {
                 struct page *page;
                 unsigned long nr, ret;
+                int ra;
 
                 /* nr is the maximum number of bytes to copy from this page */
                 nr = huge_page_size(h);
@@ -274,16 +275,19 @@ static ssize_t hugetlbfs_read(struct file *filp, char __user *buf,
                          */
                         ret = len < nr ? len : nr;
                         if (clear_user(buf, ret))
-                                ret = -EFAULT;
+                                ra = -EFAULT;
+                        else
+                                ra = 0;
                 } else {
                         /*
                          * We have the page, copy it to user space buffer.
                          */
-                        ret = hugetlbfs_read_actor(page, offset, buf, len, nr);
+                        ra = hugetlbfs_read_actor(page, offset, buf, len, nr);
+                        ret = ra;
                 }
-                if (ret < 0) {
+                if (ra < 0) {
                         if (retval == 0)
-                                retval = ret;
+                                retval = ra;
                         if (page)
                                 page_cache_release(page);
                         goto out;