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| author | Dominik Brodowski <linux@dominikbrodowski.net> | 2022-01-24 23:29:47 +0300 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2022-02-05 07:10:49 +0300 |
| commit | 6ff6304497c900a0284e3aa89ad86f0ed01f86d8 (patch) | |
| tree | 7ab0a7bc45432f7bea1f9965d074074207898994 | |
| parent | 26a03981318d2e0f12456a1041fe3bf8af5416cf (diff) | |
| download | linux-6ff6304497c900a0284e3aa89ad86f0ed01f86d8.tar.xz | |
hwrng: core - read() callback must be called for size of 32 or more bytes
According to <linux/hw_random.h>, the @max parameter of the ->read
callback "is a multiple of 4 and >= 32 bytes". That promise was not
kept by add_early_randomness(), which only asked for 16 bytes. As
rng_buffer_size() is at least 32, we can simply ask for 32 bytes.
Cc: Matt Mackall <mpm@selenic.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
| -rw-r--r-- | drivers/char/hw_random/core.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index e860e044b19e..c2d260b5dd92 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -64,10 +64,9 @@ static size_t rng_buffer_size(void) static void add_early_randomness(struct hwrng *rng) { int bytes_read; - size_t size = min_t(size_t, 16, rng_buffer_size()); mutex_lock(&reading_mutex); - bytes_read = rng_get_data(rng, rng_buffer, size, 0); + bytes_read = rng_get_data(rng, rng_buffer, 32, 0); mutex_unlock(&reading_mutex); if (bytes_read > 0) add_device_randomness(rng_buffer, bytes_read); |