4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx>
commit a5dfefb1c3f3db81662556393fd9283511e08430 upstream.
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@xxxxxxxxx>
Signed-off-by: Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
crypto/drbg.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -1768,9 +1768,8 @@ static int drbg_kcapi_sym_ctr(struct drb
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;
}