kernel: avoid overflow in cmp_range
Avoid overflow possibility.
[ The overflow is purely theoretical, since this is used for memory
ranges that aren't even close to using the full 64 bits, but this is
the right thing to do regardless. - Linus ]
Signed-off-by: Louis Langholtz <lou_langholtz@me.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Peter Anvin <hpa@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/range.c b/kernel/range.c
index 322ea8e..82cfc28 100644
--- a/kernel/range.c
+++ b/kernel/range.c
@@ -113,12 +113,12 @@
{
const struct range *r1 = x1;
const struct range *r2 = x2;
- s64 start1, start2;
- start1 = r1->start;
- start2 = r2->start;
-
- return start1 - start2;
+ if (r1->start < r2->start)
+ return -1;
+ if (r1->start > r2->start)
+ return 1;
+ return 0;
}
int clean_sort_range(struct range *range, int az)