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 <[email protected]> Signed-off-by: Gilad Ben-Yossef <[email protected]> CC: [email protected] Signed-off-by: Herbert Xu <[email protected]>
opendata26 · May 23, 2017 · a5dfefb · a5dfefb
1 parent e68368a
commit a5dfefb
Showing 1 changed file with 2 additions and 3 deletions.
diff --git a/crypto/drbg.c b/crypto/drbg.c
@@ -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;
 			}