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-rw-r--r--drivers/char/random.c17
1 files changed, 7 insertions, 10 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 394cbd814a0b..e15063d61460 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -523,7 +523,6 @@ EXPORT_SYMBOL(get_random_bytes);
static ssize_t get_random_bytes_user(void __user *buf, size_t nbytes)
{
- bool large_request = nbytes > 256;
ssize_t ret = 0;
size_t len;
u32 chacha_state[CHACHA_STATE_WORDS];
@@ -549,15 +548,6 @@ static ssize_t get_random_bytes_user(void __user *buf, size_t nbytes)
}
do {
- if (large_request) {
- if (signal_pending(current)) {
- if (!ret)
- ret = -ERESTARTSYS;
- break;
- }
- cond_resched();
- }
-
chacha20_block(chacha_state, output);
if (unlikely(chacha_state[12] == 0))
++chacha_state[13];
@@ -571,6 +561,13 @@ static ssize_t get_random_bytes_user(void __user *buf, size_t nbytes)
nbytes -= len;
buf += len;
ret += len;
+
+ BUILD_BUG_ON(PAGE_SIZE % CHACHA_BLOCK_SIZE != 0);
+ if (!(ret % PAGE_SIZE) && nbytes) {
+ if (signal_pending(current))
+ break;
+ cond_resched();
+ }
} while (nbytes);
memzero_explicit(output, sizeof(output));