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authorLinus Torvalds <torvalds@linux-foundation.org>2022-03-16 11:50:35 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-03-16 11:50:35 -0700
commitd34c58247f73c5358ceae1ae648fb9daa408ef23 (patch)
tree12eebdd0412d36715505b65f4a3e0d74986cd950
parent56e337f2cf1326323844927a04e9dbce9a244835 (diff)
parenta680b1832ced3b5fa7c93484248fd221ea0d614b (diff)
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
-rw-r--r--drivers/crypto/qcom-rng.c17
1 files changed, 10 insertions, 7 deletions
diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c
index 99ba8d51d102..11f30fd48c14 100644
--- a/drivers/crypto/qcom-rng.c
+++ b/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,