On Tue, 14 Feb 2012, Yang Bai wrote:
Before, if the total alloc size is overflow,
we just return NULL like alloc fail. But they
are two different type problems. The former looks
more like a programming problem. So add a warning
here.
Signed-off-by: Yang Bai <hamo.by@xxxxxxxxx>
---
include/linux/slab.h | 4 +++-
1 files changed, 3 insertions(+), 1 deletions(-)
diff --git a/include/linux/slab.h b/include/linux/slab.h
index 573c809..5865237 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -242,8 +242,10 @@ size_t ksize(const void *);
*/
static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
{
- if (size != 0 && n > ULONG_MAX / size)
+ if (size != 0 && n > ULONG_MAX / size) {
+ WARN(1, "Alloc memory size (%lu * %lu) overflow.", n, size);
return NULL;
+ }
return __kmalloc(n * size, flags | __GFP_ZERO);
}
Did you check how much kernel text size increases? I'm pretty sure we'd
need to wrap this with CONFIG_SLAB_OVERFLOW ifdef.
Pekka
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>