Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git…

…/herbert/crypto-2.6

Pull crypto fix from Herbert Xu:
 "This fixes a bug where qcom-rng can return a buffer that is not
  completely filled with random data"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: qcom-rng - ensure buffer for generate is completely filled

drivers/crypto/qcom-rng.c

@@ -8,6 +8,7 @@
 #include <linux/clk.h>
 #include <linux/crypto.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
@@ -43,16 +44,19 @@ static int qcom_rng_read(struct qcom_rng *rng, u8 *data, unsigned int max)
 {
 	unsigned int currsize = 0;
 	u32 val;
+	int ret;
 
 	/* read random data from hardware */
 	do {
-		val = readl_relaxed(rng->base + PRNG_STATUS);
-		if (!(val & PRNG_STATUS_DATA_AVAIL))
-			break;
+		ret = readl_poll_timeout(rng->base + PRNG_STATUS, val,
+					 val & PRNG_STATUS_DATA_AVAIL,
+					 200, 10000);
+		if (ret)
+			return ret;
 
 		val = readl_relaxed(rng->base + PRNG_DATA_OUT);
 		if (!val)
-			break;
+			return -EINVAL;
 
 		if ((max - currsize) >= WORD_SZ) {
 			memcpy(data, &val, WORD_SZ);
@@ -61,11 +65,10 @@ static int qcom_rng_read(struct qcom_rng *rng, u8 *data, unsigned int max)
 		} else {
 			/* copy only remaining bytes */
 			memcpy(data, &val, max - currsize);
-			break;
 		}
 	} while (currsize < max);
 
-	return currsize;
+	return 0;
 }
 
 static int qcom_rng_generate(struct crypto_rng *tfm,
@@ -87,7 +90,7 @@ static int qcom_rng_generate(struct crypto_rng *tfm,
 	mutex_unlock(&rng->lock);
 	clk_disable_unprepare(rng->clk);
 
-	return 0;
+	return ret;
 }
 
 static int qcom_rng_seed(struct crypto_rng *tfm, const u8 *seed,