crypto: sun4i-ss - linearize buffers content must be kept

[ 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>

diff --git a/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c b/drivers/crypto/allwinner/sun4i-ss/sun4i-ss-cipher.c
index b72de89..19f1aa5 100644 (file)
--- 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 163962f..02105b3 100644 (file)
--- 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];