[PATCH 3/3] crypto: qce - check dma_map_sg() result for the source scatterlist

[ZhaoJinming]

qce_aead_async_req_handle() maps the source scatterlist with
dma_map_sg(), which returns 0 on failure, but the result is checked
with:

	if (src_nents < 0) {
		ret = src_nents;
		goto error_unmap_dst;
	}

so a mapping failure is not detected.  The code then calls
qce_dma_prep_sgs() with zero source entries, which fails, and the error
path calls dma_unmap_sg() on a scatterlist that was never mapped.

Check for !src_nents instead and return -EIO, matching the check that is
already used for the destination scatterlist.  The error_unmap_dst path
skips the source unmap and only releases the destination mapping, which
is the one that was successfully created.

Fixes: 9363efb4181c ("crypto: qce - Add support for AEAD algorithms")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: ZhaoJinming <zhaojinming@xxxxxxxxxxxxx>
---
 drivers/crypto/qce/aead.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/qce/aead.c b/drivers/crypto/qce/aead.c
index 5bf59cb9ae9a..15ce778f019a 100644
--- a/drivers/crypto/qce/aead.c
+++ b/drivers/crypto/qce/aead.c
@@ -456,8 +456,8 @@ qce_aead_async_req_handle(struct crypto_async_request *async_req)
 
 	if (diff_dst) {
 		src_nents = dma_map_sg(qce->dev, rctx->src_sg, rctx->src_nents, dir_src);
-		if (src_nents < 0) {
-			ret = src_nents;
+		if (!src_nents) {
+			ret = -EIO;
 			goto error_unmap_dst;
 		}
 	} else {

-- 
2.50.1