[PATCH] cpuset read past eof memory leak fix
Don't leak a page of memory if user reads a cpuset file past eof.
Signed-off-by: KUROSAWA Takahiro <kurosawa@valinux.co.jp>
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 79866bc..6a6e87b 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -969,7 +969,7 @@
ssize_t retval = 0;
char *s;
char *start;
- size_t n;
+ ssize_t n;
if (!(page = (char *)__get_free_page(GFP_KERNEL)))
return -ENOMEM;
@@ -999,12 +999,13 @@
*s++ = '\n';
*s = '\0';
- /* Do nothing if *ppos is at the eof or beyond the eof. */
- if (s - page <= *ppos)
- return 0;
-
start = page + *ppos;
n = s - start;
+
+ /* Do nothing if *ppos is at the eof or beyond the eof. */
+ if (n <= 0)
+ goto out;
+
retval = n - copy_to_user(buf, start, min(n, nbytes));
*ppos += retval;
out: