[PATCH v4 08/15] crypto: ti - Validate sg_nents_for_len() return value in DTHEv2 AES

[T Pratham <t-pratham@ti.com>]

sg_nents_for_len() returns -EINVAL if the supplied scatterlist is
shorter than the requested length.

Add explicit checks after each sg_nents_for_len() call in DTHEv2 AES
driver.

Fixes: 52f641bc63a46 ("crypto: ti - Add driver for DTHE V2 AES Engine (ECB, CBC)")
Signed-off-by: T Pratham <t-pratham@ti.com>
---
 drivers/crypto/ti/dthev2-aes.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/crypto/ti/dthev2-aes.c b/drivers/crypto/ti/dthev2-aes.c
index aeccc235cb667..bc3591ec58a1c 100644
--- a/drivers/crypto/ti/dthev2-aes.c
+++ b/drivers/crypto/ti/dthev2-aes.c
@@ -354,6 +354,11 @@ static int dthe_aes_run(struct crypto_engine *engine, void *areq)
 	u32 aes_irqenable_val = readl_relaxed(aes_base_reg + DTHE_P_AES_IRQENABLE);
 	u32 aes_sysconfig_val = readl_relaxed(aes_base_reg + DTHE_P_AES_SYSCONFIG);
 
+	if (src_nents < 0 || dst_nents < 0) {
+		ret = -EINVAL;
+		goto aes_inval_nent_err;
+	}
+
 	aes_sysconfig_val |= DTHE_AES_SYSCONFIG_DMA_DATA_IN_OUT_EN;
 	writel_relaxed(aes_sysconfig_val, aes_base_reg + DTHE_P_AES_SYSCONFIG);
 
@@ -510,6 +515,7 @@ static int dthe_aes_run(struct crypto_engine *engine, void *areq)
 	if (ret == -ENOMEM)
 		ret = dthe_aes_do_fallback(req);
 
+aes_inval_nent_err:
 	local_bh_disable();
 	crypto_finalize_skcipher_request(dev_data->engine, req, ret);
 	local_bh_enable();
-- 
2.34.1