[PATCH][next] crypto: sun8i-ss@: fix memory leak on pointer d

From: Colin King
Date: Tue Sep 29 2020 - 09:38:29 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Currently the error return path on a failed dma_mapping_error call
is not kfree'ing memory allocated to d. Add an extra error exit label
to end of the function where the kfree and return occurs to fix this
issue.

Addresses-Coverity: ("Resource leak")
Fixes: ac2614d721de ("crypto: sun8i-ss - Add support for the PRNG")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c
index 08a1473b2145..42b02720dbbf 100644
--- a/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c
+++ b/drivers/crypto/allwinner/sun8i-ss/sun8i-ss-prng.c
@@ -103,7 +103,8 @@ int sun8i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src,
dma_iv = dma_map_single(ss->dev, ctx->seed, ctx->slen, DMA_TO_DEVICE);
if (dma_mapping_error(ss->dev, dma_iv)) {
dev_err(ss->dev, "Cannot DMA MAP IV\n");
- return -EFAULT;
+ err = -EFAULT;
+ goto err_free;
}

dma_dst = dma_map_single(ss->dev, d, todo, DMA_FROM_DEVICE);
@@ -167,6 +168,7 @@ int sun8i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src,
memcpy(ctx->seed, d + dlen, ctx->slen);
}
memzero_explicit(d, todo);
+err_free:
kfree(d);

return err;
--
2.27.0