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[5.11,177/775] crypto: sun4i-ss - linearize buffers content must be kept

Message ID 20210301161210.377400600@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg KH March 1, 2021, 4:05 p.m. UTC 
From: Corentin Labbe <clabbe@baylibre.com>

[ Upstream commit 583513510a7acd2306787865bcd19ebb2f629d42 ]

When running the non-optimized cipher function, SS produce partial random
output.
This is due to linearize buffers being reseted after each loop.

For preserving stack, instead of moving them back to start of function,
I move them in sun4i_ss_ctx.

Fixes: 8d3bcb9900ca ("crypto: sun4i-ss - reduce stack usage")
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c | 12 ++++--------
 drivers/crypto/allwinner/sun4i-ss/sun4i-ss.h        |  2 ++
 2 files changed, 6 insertions(+), 8 deletions(-)
diff mbox series

Patch

diff --git a/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c b/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c
index b72de8939497b..19f1aa577ed4d 100644
--- a/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c
+++ b/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c
@@ -233,8 +233,6 @@  static int sun4i_ss_cipher_poll(struct skcipher_request *areq)
 
 	while (oleft) {
 		if (ileft) {
-			char buf[4 * SS_RX_MAX];/* buffer for linearize SG src */
-
 			/*
 			 * todo is the number of consecutive 4byte word that we
 			 * can read from current SG
@@ -256,12 +254,12 @@  static int sun4i_ss_cipher_poll(struct skcipher_request *areq)
 				 */
 				todo = min(rx_cnt * 4 - ob, ileft);
 				todo = min_t(size_t, todo, mi.length - oi);
-				memcpy(buf + ob, mi.addr + oi, todo);
+				memcpy(ss->buf + ob, mi.addr + oi, todo);
 				ileft -= todo;
 				oi += todo;
 				ob += todo;
 				if (!(ob % 4)) {
-					writesl(ss->base + SS_RXFIFO, buf,
+					writesl(ss->base + SS_RXFIFO, ss->buf,
 						ob / 4);
 					ob = 0;
 				}
@@ -295,13 +293,11 @@  static int sun4i_ss_cipher_poll(struct skcipher_request *areq)
 				oo = 0;
 			}
 		} else {
-			char bufo[4 * SS_TX_MAX]; /* buffer for linearize SG dst */
-
 			/*
 			 * read obl bytes in bufo, we read at maximum for
 			 * emptying the device
 			 */
-			readsl(ss->base + SS_TXFIFO, bufo, tx_cnt);
+			readsl(ss->base + SS_TXFIFO, ss->bufo, tx_cnt);
 			obl = tx_cnt * 4;
 			obo = 0;
 			do {
@@ -313,7 +309,7 @@  static int sun4i_ss_cipher_poll(struct skcipher_request *areq)
 				 */
 				todo = min_t(size_t,
 					     mo.length - oo, obl - obo);
-				memcpy(mo.addr + oo, bufo + obo, todo);
+				memcpy(mo.addr + oo, ss->bufo + obo, todo);
 				oleft -= todo;
 				obo += todo;
 				oo += todo;
diff --git a/drivers/crypto/allwinner/sun4i-ss/sun4i-ss.h b/drivers/crypto/allwinner/sun4i-ss/sun4i-ss.h
index 5c291e4a6857b..c242fccb2ab67 100644
--- a/drivers/crypto/allwinner/sun4i-ss/sun4i-ss.h
+++ b/drivers/crypto/allwinner/sun4i-ss/sun4i-ss.h
@@ -148,6 +148,8 @@  struct sun4i_ss_ctx {
 	struct reset_control *reset;
 	struct device *dev;
 	struct resource *res;
+	char buf[4 * SS_RX_MAX];/* buffer for linearize SG src */
+	char bufo[4 * SS_TX_MAX]; /* buffer for linearize SG dst */
 	spinlock_t slock; /* control the use of the device */
 #ifdef CONFIG_CRYPTO_DEV_SUN4I_SS_PRNG
 	u32 seed[SS_SEED_LEN / BITS_PER_LONG];