crypto: api - Only abort operations on fatal signal

commit 3fc89adb upstream.

Currently a number of Crypto API operations may fail when a signal
occurs.  This causes nasty problems as the caller of those operations
are often not in a good position to restart the operation.

In fact there is currently no need for those operations to be
interrupted by user signals at all.  All we need is for them to
be killable.

This patch replaces the relevant calls of signal_pending with
fatal_signal_pending, and wait_for_completion_interruptible with
wait_for_completion_killable, respectively.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

crypto/ablkcipher.c

@@ -695,7 +695,7 @@ struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
 err:
 		if (err != -EAGAIN)
 			break;
-		if (signal_pending(current)) {
+		if (fatal_signal_pending(current)) {
 			err = -EINTR;
 			break;
 		}

crypto/algapi.c

@@ -325,7 +325,7 @@ static void crypto_wait_for_test(struct crypto_larval *larval)
 		crypto_alg_tested(larval->alg.cra_driver_name, 0);
 	}
 
-	err = wait_for_completion_interruptible(&larval->completion);
+	err = wait_for_completion_killable(&larval->completion);
 	WARN_ON(err);
 
 out:

crypto/api.c

@@ -172,7 +172,7 @@ static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg)
 	struct crypto_larval *larval = (void *)alg;
 	long timeout;
 
-	timeout = wait_for_completion_interruptible_timeout(
+	timeout = wait_for_completion_killable_timeout(
 		&larval->completion, 60 * HZ);
 
 	alg = larval->adult;
@@ -435,7 +435,7 @@ struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask)
 err:
 		if (err != -EAGAIN)
 			break;
-		if (signal_pending(current)) {
+		if (fatal_signal_pending(current)) {
 			err = -EINTR;
 			break;
 		}
@@ -552,7 +552,7 @@ void *crypto_alloc_tfm(const char *alg_name,
 err:
 		if (err != -EAGAIN)
 			break;
-		if (signal_pending(current)) {
+		if (fatal_signal_pending(current)) {
 			err = -EINTR;
 			break;
 		}

crypto/crypto_user.c

@@ -367,7 +367,7 @@ static struct crypto_alg *crypto_user_aead_alg(const char *name, u32 type,
 		err = PTR_ERR(alg);
 		if (err != -EAGAIN)
 			break;
-		if (signal_pending(current)) {
+		if (fatal_signal_pending(current)) {
 			err = -EINTR;
 			break;
 		}