kdfs: make free calls check for NULL.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10496)

9 files changed, 37 insertions, 19 deletions

diff --git a/providers/implementations/kdfs/hkdf.c b/providers/implementations/kdfs/hkdf.c
index 66d70635a6..d9f53a67e7 100644
--- a/providers/implementations/kdfs/hkdf.c
+++ b/providers/implementations/kdfs/hkdf.c
@@ -75,8 +75,10 @@ static void kdf_hkdf_free(void *vctx)
 {
     KDF_HKDF *ctx = (KDF_HKDF *)vctx;
 
-    kdf_hkdf_reset(ctx);
-    OPENSSL_free(ctx);
+    if (ctx != NULL) {
+        kdf_hkdf_reset(ctx);
+        OPENSSL_free(ctx);
+    }
 }
 
 static void kdf_hkdf_reset(void *vctx)
diff --git a/providers/implementations/kdfs/kbkdf.c b/providers/implementations/kdfs/kbkdf.c
index 1c0e2b2b78..acc7d7f47b 100644
--- a/providers/implementations/kdfs/kbkdf.c
+++ b/providers/implementations/kdfs/kbkdf.c
@@ -113,8 +113,10 @@ static void kbkdf_free(void *vctx)
 {
     KBKDF *ctx = (KBKDF *)vctx;
 
-    kbkdf_reset(ctx);
-    OPENSSL_free(ctx);
+    if (ctx != NULL) {
+        kbkdf_reset(ctx);
+        OPENSSL_free(ctx);
+    }
 }
 
 static void kbkdf_reset(void *vctx)
diff --git a/providers/implementations/kdfs/krb5kdf.c b/providers/implementations/kdfs/krb5kdf.c
index 83dfa9c2dc..ee7742ea27 100644
--- a/providers/implementations/kdfs/krb5kdf.c
+++ b/providers/implementations/kdfs/krb5kdf.c
@@ -63,8 +63,10 @@ static void krb5kdf_free(void *vctx)
 {
     KRB5KDF_CTX *ctx = (KRB5KDF_CTX *)vctx;
 
-    krb5kdf_reset(ctx);
-    OPENSSL_free(ctx);
+    if (ctx != NULL) {
+        krb5kdf_reset(ctx);
+        OPENSSL_free(ctx);
+    }
 }
 
 static void krb5kdf_reset(void *vctx)
diff --git a/providers/implementations/kdfs/pbkdf2.c b/providers/implementations/kdfs/pbkdf2.c
index f08063fab5..077b93afb0 100644
--- a/providers/implementations/kdfs/pbkdf2.c
+++ b/providers/implementations/kdfs/pbkdf2.c
@@ -80,8 +80,10 @@ static void kdf_pbkdf2_free(void *vctx)
 {
     KDF_PBKDF2 *ctx = (KDF_PBKDF2 *)vctx;
 
-    kdf_pbkdf2_cleanup(ctx);
-    OPENSSL_free(ctx);
+    if (ctx != NULL) {
+        kdf_pbkdf2_cleanup(ctx);
+        OPENSSL_free(ctx);
+    }
 }
 
 static void kdf_pbkdf2_reset(void *vctx)
diff --git a/providers/implementations/kdfs/scrypt.c b/providers/implementations/kdfs/scrypt.c
index a067a9a91c..425db1af6f 100644
--- a/providers/implementations/kdfs/scrypt.c
+++ b/providers/implementations/kdfs/scrypt.c
@@ -74,9 +74,11 @@ static void kdf_scrypt_free(void *vctx)
 {
     KDF_SCRYPT *ctx = (KDF_SCRYPT *)vctx;
 
-    EVP_MD_meth_free(ctx->sha256);
-    kdf_scrypt_reset(ctx);
-    OPENSSL_free(ctx);
+    if (ctx != NULL) {
+        EVP_MD_meth_free(ctx->sha256);
+        kdf_scrypt_reset(ctx);
+        OPENSSL_free(ctx);
+    }
 }
 
 static void kdf_scrypt_reset(void *vctx)
diff --git a/providers/implementations/kdfs/sshkdf.c b/providers/implementations/kdfs/sshkdf.c
index d5484f4acb..508fb6350a 100644
--- a/providers/implementations/kdfs/sshkdf.c
+++ b/providers/implementations/kdfs/sshkdf.c
@@ -63,8 +63,10 @@ static void kdf_sshkdf_free(void *vctx)
 {
     KDF_SSHKDF *ctx = (KDF_SSHKDF *)vctx;
 
-    kdf_sshkdf_reset(ctx);
-    OPENSSL_free(ctx);
+    if (ctx != NULL) {
+        kdf_sshkdf_reset(ctx);
+        OPENSSL_free(ctx);
+    }
 }
 
 static void kdf_sshkdf_reset(void *vctx)
diff --git a/providers/implementations/kdfs/sskdf.c b/providers/implementations/kdfs/sskdf.c
index 4f69eec7f6..2c4600d205 100644
--- a/providers/implementations/kdfs/sskdf.c
+++ b/providers/implementations/kdfs/sskdf.c
@@ -315,8 +315,10 @@ static void sskdf_free(void *vctx)
 {
     KDF_SSKDF *ctx = (KDF_SSKDF *)vctx;
 
-    sskdf_reset(ctx);
-    OPENSSL_free(ctx);
+    if (ctx != NULL) {
+        sskdf_reset(ctx);
+        OPENSSL_free(ctx);
+    }
 }
 
 static int sskdf_set_buffer(unsigned char **out, size_t *out_len,
diff --git a/providers/implementations/kdfs/tls1_prf.c b/providers/implementations/kdfs/tls1_prf.c
index 0a83753a8a..84d712afc5 100644
--- a/providers/implementations/kdfs/tls1_prf.c
+++ b/providers/implementations/kdfs/tls1_prf.c
@@ -106,8 +106,10 @@ static void kdf_tls1_prf_free(void *vctx)
 {
     TLS1_PRF *ctx = (TLS1_PRF *)vctx;
 
-    kdf_tls1_prf_reset(ctx);
-    OPENSSL_free(ctx);
+    if (ctx != NULL) {
+        kdf_tls1_prf_reset(ctx);
+        OPENSSL_free(ctx);
+    }
 }
 
 static void kdf_tls1_prf_reset(void *vctx)
diff --git a/providers/implementations/kdfs/x942kdf.c b/providers/implementations/kdfs/x942kdf.c
index 5a84d50968..1459e0f661 100644
--- a/providers/implementations/kdfs/x942kdf.c
+++ b/providers/implementations/kdfs/x942kdf.c
@@ -266,8 +266,10 @@ static void x942kdf_free(void *vctx)
 {
     KDF_X942 *ctx = (KDF_X942 *)vctx;
 
-    x942kdf_reset(ctx);
-    OPENSSL_free(ctx);
+    if (ctx != NULL) {
+        x942kdf_reset(ctx);
+        OPENSSL_free(ctx);
+    }
 }
 
 static int x942kdf_set_buffer(unsigned char **out, size_t *out_len,