dlmalloc: Fix integer overflow in request2size()
req is of type size_t, casting it to long opens the door
for an integer overflow.
Values between LONG_MAX - (SIZE_SZ + MALLOC_ALIGN_MASK) - 1 and LONG_MAX
cause and overflow such that request2size() returns MINSIZE.
Fix by removing the cast.
The origin of the cast is unclear, it's in u-boot and ppcboot since ever
and predates the CVS history.
Doug Lea's original dlmalloc implementation also doesn't have it.
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/common/dlmalloc.c b/common/dlmalloc.c
index 1e1602a..48e83da 100644
--- a/common/dlmalloc.c
+++ b/common/dlmalloc.c
@@ -386,8 +386,8 @@
/* pad request bytes into a usable size */
#define request2size(req) \
- (((long)((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) < \
- (long)(MINSIZE + MALLOC_ALIGN_MASK)) ? MINSIZE : \
+ ((((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) < \
+ (MINSIZE + MALLOC_ALIGN_MASK)) ? MINSIZE : \
(((req) + (SIZE_SZ + MALLOC_ALIGN_MASK)) & ~(MALLOC_ALIGN_MASK)))
/* Check if m has acceptable alignment */