hugetlb: unsigned ret cannot be negative
Roel Kluin [Tue, 6 Jan 2009 22:40:14 +0000 (14:40 -0800)]
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>

fs/hugetlbfs/inode.c

index 0ab0c6f..6903d37 100644 (file)
@@ -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;