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>
This commit is contained in:
Gilad Ben-Yossef 2017-05-18 16:29:24 +03:00 committed by Herbert Xu
parent e68368aed5
commit a5dfefb1c3

View file

@ -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;
}