[PATCH 2/2] crypto: asymmetric_keys - simplify asymmetric_key_hex_to_key_id

[Thorsten Blum <thorsten.blum@linux.dev>]

Use struct_size() to calculate the number of bytes to allocate for the
asymmetric key id.  Add a local variable to store the hex data length
instead of recalculating it.

The variable 'ret', whose name implies a return variable, is only used
to temporarily store the result of __asymmetric_key_hex_to_key_id(). Use
the result directly and remove the local variable.

No functional changes.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 crypto/asymmetric_keys/asymmetric_type.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c
index aea925c88973..b73b8b983bfa 100644
--- a/crypto/asymmetric_keys/asymmetric_type.c
+++ b/crypto/asymmetric_keys/asymmetric_type.c
@@ -228,7 +228,7 @@ struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id)
 {
 	struct asymmetric_key_id *match_id;
 	size_t asciihexlen;
-	int ret;
+	size_t hexlen;
 
 	if (!*id)
 		return ERR_PTR(-EINVAL);
@@ -236,12 +236,11 @@ struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id)
 	if (asciihexlen & 1)
 		return ERR_PTR(-EINVAL);
 
-	match_id = kmalloc(sizeof(struct asymmetric_key_id) + asciihexlen / 2,
-			   GFP_KERNEL);
+	hexlen = asciihexlen / 2;
+	match_id = kmalloc(struct_size(match_id, data, hexlen), GFP_KERNEL);
 	if (!match_id)
 		return ERR_PTR(-ENOMEM);
-	ret = __asymmetric_key_hex_to_key_id(id, match_id, asciihexlen / 2);
-	if (ret < 0) {
+	if (__asymmetric_key_hex_to_key_id(id, match_id, hexlen) < 0) {
 		kfree(match_id);
 		return ERR_PTR(-EINVAL);
 	}
-- 
2.51.0