Commit a5dfefb1 authored May 18, 2017 by Gilad Ben-Yossef Committed by Herbert Xu May 23, 2017

crypto: drbg - wait for crypto op not signal safe



drbg_kcapi_sym_ctr() was using wait_for_completion_interruptible() to
wait for completion of async crypto op but if a signal occurs it
may return before DMA ops of HW crypto provider finish, thus
corrupting the output buffer.

Resolve this by using wait_for_completion() instead.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
CC: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

parent e68368ae

crypto/drbg.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -1767,9 +1767,8 @@ static int drbg_kcapi_sym_ctr(struct drbg_state *drbg,
		break;
		case -EINPROGRESS:
		case -EBUSY:
		ret = wait_for_completion_interruptible(
		&drbg->ctr_completion);
		if (!ret && !drbg->ctr_async_err) {
		wait_for_completion(&drbg->ctr_completion);
		if (!drbg->ctr_async_err) {
		reinit_completion(&drbg->ctr_completion);
		break;
		}