[PATCH 19/22] lib: scatterlist: don't assert last element for empty sglist

[Ahmad Fatoum]

A BUG_ON in sg_last tries to verify that the last element in a scatter
gather list is indeed marked as such in its flags.

clang-analyzer warns that this would make the function fail for an empty
list, so let's add a NULL-check into the BUG_ON.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 lib/scatterlist.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index f7b06013a552..6a4e1e91f8f1 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -105,7 +105,7 @@ struct scatterlist *sg_last(struct scatterlist *sgl, unsigned int nents)
 	for_each_sg(sgl, sg, nents, i)
 		ret = sg;
 
-	BUG_ON(!sg_is_last(ret));
+	BUG_ON(ret && !sg_is_last(ret));
 	return ret;
 }
 EXPORT_SYMBOL(sg_last);
-- 
2.39.5