[PATCH AUTOSEL 4.19 29/31] crypto: lrw - simplify error handling in create()

From: Sasha Levin
Date: Thu May 14 2020 - 14:55:19 EST


From: Eric Biggers <ebiggers@xxxxxxxxxx>

[ Upstream commit d57063103332b95eac9c118900f35700a491da08 ]

Simplify the error handling in the LRW template's ->create() function by
taking advantage of crypto_drop_skcipher() now accepting (as a no-op) a
spawn that hasn't been grabbed yet.

Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
crypto/lrw.c | 28 +++++++++++-----------------
1 file changed, 11 insertions(+), 17 deletions(-)

diff --git a/crypto/lrw.c b/crypto/lrw.c
index 5504d1325a56a..11d079c44cafc 100644
--- a/crypto/lrw.c
+++ b/crypto/lrw.c
@@ -508,15 +508,15 @@ static int create(struct crypto_template *tmpl, struct rtattr **tb)

err = -EINVAL;
if (alg->base.cra_blocksize != LRW_BLOCK_SIZE)
- goto err_drop_spawn;
+ goto err_free_inst;

if (crypto_skcipher_alg_ivsize(alg))
- goto err_drop_spawn;
+ goto err_free_inst;

err = crypto_inst_setname(skcipher_crypto_instance(inst), "lrw",
&alg->base);
if (err)
- goto err_drop_spawn;
+ goto err_free_inst;

err = -EINVAL;
cipher_name = alg->base.cra_name;
@@ -529,20 +529,20 @@ static int create(struct crypto_template *tmpl, struct rtattr **tb)

len = strlcpy(ecb_name, cipher_name + 4, sizeof(ecb_name));
if (len < 2 || len >= sizeof(ecb_name))
- goto err_drop_spawn;
+ goto err_free_inst;

if (ecb_name[len - 1] != ')')
- goto err_drop_spawn;
+ goto err_free_inst;

ecb_name[len - 1] = 0;

if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
"lrw(%s)", ecb_name) >= CRYPTO_MAX_ALG_NAME) {
err = -ENAMETOOLONG;
- goto err_drop_spawn;
+ goto err_free_inst;
}
} else
- goto err_drop_spawn;
+ goto err_free_inst;

inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC;
inst->alg.base.cra_priority = alg->base.cra_priority;
@@ -568,17 +568,11 @@ static int create(struct crypto_template *tmpl, struct rtattr **tb)
inst->free = free;

err = skcipher_register_instance(tmpl, inst);
- if (err)
- goto err_drop_spawn;
-
-out:
- return err;
-
-err_drop_spawn:
- crypto_drop_skcipher(spawn);
+ if (err) {
err_free_inst:
- kfree(inst);
- goto out;
+ free(inst);
+ }
+ return err;
}

static struct crypto_template crypto_tmpl = {
--
2.20.1