lib/scatterlist: error handling in __sg_alloc_table()
I was reviewing code which I suspected might allocate a zero size SG
table. That will cause memory corruption. Also we can't return before
doing the memset or we could end up using uninitialized memory in the
cleanup path.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index 129a82f..a685c8a 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -247,13 +247,15 @@
struct scatterlist *sg, *prv;
unsigned int left;
+ memset(table, 0, sizeof(*table));
+
+ if (nents == 0)
+ return -EINVAL;
#ifndef ARCH_HAS_SG_CHAIN
if (WARN_ON_ONCE(nents > max_ents))
return -EINVAL;
#endif
- memset(table, 0, sizeof(*table));
-
left = nents;
prv = NULL;
do {