Fixes #30979: Added `BN_CTX_end` before free in sm2_sign and sm2_crypt.

Added `BN_CTX_end` call before `BN_CTX_free` to keep the pattern
consistent with functions like `sm2_sig_verify`, `sm2_sig_gen`,
for instance.

Added missing `BN_CTX_start()` and `BN_CTX_end()` calls in
`ossl_sm2_compute_z_digest`. Fixed formatting.

Fixes: 3d328a445c2a "Add SM2 signature and ECIES schemes"
Reviewed-by: Eugene Syromiatnikov <esyr@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.foundation>
MergeDate: Wed May 13 07:24:17 2026
(Merged from https://github.com/openssl/openssl/pull/31069)

diff --git a/crypto/sm2/sm2_crypt.c b/crypto/sm2/sm2_crypt.c
index e7ae6a8bd0bd89ba069b62801a767938121bae8e..a1cbd88c2df81f8ee449c290d0c979a45cafc77e 100644 (file)
--- a/crypto/sm2/sm2_crypt.c
+++ b/crypto/sm2/sm2_crypt.c
@@ -282,6 +282,7 @@ done:
     OPENSSL_free(x2y2);
     OPENSSL_free(C3);
     EVP_MD_CTX_free(hash);
+    BN_CTX_end(ctx);
     BN_CTX_free(ctx);
     EC_POINT_free(kG);
     EC_POINT_free(kP);
@@ -422,6 +423,7 @@ done:
     OPENSSL_free(x2y2);
     OPENSSL_free(computed_C3);
     EC_POINT_free(C1);
+    BN_CTX_end(ctx);
     BN_CTX_free(ctx);
     SM2_Ciphertext_free(sm2_ctext);
     EVP_MD_CTX_free(hash);

diff --git a/crypto/sm2/sm2_sign.c b/crypto/sm2/sm2_sign.c
index 755f7edd2041c75e9c0f926c864f9fd508da2b12..5e29900968ad47d3eedaf7a638381d0ada0455cf 100644 (file)
--- a/crypto/sm2/sm2_sign.c
+++ b/crypto/sm2/sm2_sign.c
@@ -75,6 +75,7 @@ int ossl_sm2_compute_z_digest(uint8_t *out,
         goto done;
     }
 
+    BN_CTX_start(ctx);
     p = BN_CTX_get(ctx);
     a = BN_CTX_get(ctx);
     b = BN_CTX_get(ctx);
@@ -161,6 +162,7 @@ int ossl_sm2_compute_z_digest(uint8_t *out,
 
 done:
     OPENSSL_free(buf);
+    BN_CTX_end(ctx);
     BN_CTX_free(ctx);
     EVP_MD_CTX_free(hash);
     return rc;
@@ -342,6 +344,7 @@ done:
         BN_free(s);
     }
 
+    BN_CTX_end(ctx);
     BN_CTX_free(ctx);
     EC_POINT_free(kG);
     return sig;
@@ -425,8 +428,8 @@ static int sm2_sig_verify(const EC_KEY *key, const ECDSA_SIG *sig,
         ret = 1;
 
 done:
-    BN_CTX_end(ctx);
     EC_POINT_free(pt);
+    BN_CTX_end(ctx);
     BN_CTX_free(ctx);
     return ret;
 }