[4/4] crypto: crypto_user - clean up report structure copying

Commit Message

Eric Biggers Nov. 3, 2018, 9:56 p.m. UTC

From: Eric Biggers <[e-mail]>

There have been a pretty ridiculous number of issues with initializing
the report structures that are copied to userspace by NETLINK_CRYPTO.
Commit 4473710df1f8 ("crypto: user - Prepare for CRYPTO_MAX_ALG_NAME
expansion") replaced some strncpy()s with strlcpy()s, thereby
introducing information leaks.  Later two other people tried to replace
other strncpy()s with strlcpy() too, which would have introduced even
more information leaks:

    - https://lore.kernel.org/patchwork/patch/954991/
    - https://patchwork.kernel.org/patch/10434351/

Commit cac5818c25d0 ("crypto: user - Implement a generic crypto
statistics") also uses the buggy strlcpy() approach and therefore leaks
uninitialized memory to userspace.  A fix was proposed, but it was
originally incomplete.

Seeing as how apparently no one can get this right with the current
approach, change all the reporting functions to:

- Start by memsetting the report structure to 0.  This guarantees it's
  always initialized, regardless of what happens later.
- Initialize all strings using strscpy().  This is safe after the
  memset, ensures null termination of long strings, avoids unnecessary
  work, and avoids the -Wstringop-truncation warnings from gcc.
- Use sizeof(var) instead of sizeof(type).  This is more robust against
  copy+paste errors.

For simplicity, also reuse the -EMSGSIZE return value from nla_put().

Signed-off-by: Eric Biggers <[e-mail]>
---
 crypto/ablkcipher.c       |  32 +++++-------
 crypto/acompress.c        |  10 ++--
 crypto/aead.c             |  14 ++----
 crypto/ahash.c            |  12 ++---
 crypto/akcipher.c         |  11 ++--
 crypto/blkcipher.c        |  16 +++---
 crypto/crypto_user_base.c |  38 +++++++-------
 crypto/crypto_user_stat.c | 102 +++++++++-----------------------------
 crypto/kpp.c              |  10 ++--
 crypto/rng.c              |  12 ++---
 crypto/scompress.c        |  11 ++--
 crypto/shash.c            |  12 ++---
 crypto/skcipher.c         |  15 +++---
 13 files changed, 96 insertions(+), 199 deletions(-)

Patch

diff --git a/crypto/ablkcipher.c b/crypto/ablkcipher.c
index 8882e90e868ea..b5e9ce19d324e 100644
--- a/crypto/ablkcipher.c
+++ b/crypto/ablkcipher.c
@@ -365,23 +365,19 @@  static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_blkcipher rblkcipher;
 
-	strncpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type));
-	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>",
+	memset(&rblkcipher, 0, sizeof(rblkcipher));
+
+	strscpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type));
+	strscpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>",
 		sizeof(rblkcipher.geniv));
-	rblkcipher.geniv[sizeof(rblkcipher.geniv) - 1] = '\0';
 
 	rblkcipher.blocksize = alg->cra_blocksize;
 	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
 	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
 	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
-		    sizeof(struct crypto_report_blkcipher), &rblkcipher))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
+		       sizeof(rblkcipher), &rblkcipher);
 }
 #else
 static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
@@ -440,23 +436,19 @@  static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_blkcipher rblkcipher;
 
-	strncpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type));
-	strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<built-in>",
+	memset(&rblkcipher, 0, sizeof(rblkcipher));
+
+	strscpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type));
+	strscpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<built-in>",
 		sizeof(rblkcipher.geniv));
-	rblkcipher.geniv[sizeof(rblkcipher.geniv) - 1] = '\0';
 
 	rblkcipher.blocksize = alg->cra_blocksize;
 	rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize;
 	rblkcipher.max_keysize = alg->cra_ablkcipher.max_keysize;
 	rblkcipher.ivsize = alg->cra_ablkcipher.ivsize;
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
-		    sizeof(struct crypto_report_blkcipher), &rblkcipher))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
+		       sizeof(rblkcipher), &rblkcipher);
 }
 #else
 static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/acompress.c b/crypto/acompress.c
index 1544b7c057fb5..0c5bedd06e705 100644
--- a/crypto/acompress.c
+++ b/crypto/acompress.c
@@ -33,15 +33,11 @@  static int crypto_acomp_report(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_acomp racomp;
 
-	strncpy(racomp.type, "acomp", sizeof(racomp.type));
+	memset(&racomp, 0, sizeof(racomp));
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_ACOMP,
-		    sizeof(struct crypto_report_acomp), &racomp))
-		goto nla_put_failure;
-	return 0;
+	strscpy(racomp.type, "acomp", sizeof(racomp.type));
 
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_ACOMP, sizeof(racomp), &racomp);
 }
 #else
 static int crypto_acomp_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/aead.c b/crypto/aead.c
index 60b3bbe973e75..189c52d1f63ab 100644
--- a/crypto/aead.c
+++ b/crypto/aead.c
@@ -119,20 +119,16 @@  static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
 	struct crypto_report_aead raead;
 	struct aead_alg *aead = container_of(alg, struct aead_alg, base);
 
-	strncpy(raead.type, "aead", sizeof(raead.type));
-	strncpy(raead.geniv, "<none>", sizeof(raead.geniv));
+	memset(&raead, 0, sizeof(raead));
+
+	strscpy(raead.type, "aead", sizeof(raead.type));
+	strscpy(raead.geniv, "<none>", sizeof(raead.geniv));
 
 	raead.blocksize = alg->cra_blocksize;
 	raead.maxauthsize = aead->maxauthsize;
 	raead.ivsize = aead->ivsize;
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_AEAD,
-		    sizeof(struct crypto_report_aead), &raead))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_AEAD, sizeof(raead), &raead);
 }
 #else
 static int crypto_aead_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/ahash.c b/crypto/ahash.c
index e21667b4e10ac..3a348fbcf8f91 100644
--- a/crypto/ahash.c
+++ b/crypto/ahash.c
@@ -498,18 +498,14 @@  static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_hash rhash;
 
-	strncpy(rhash.type, "ahash", sizeof(rhash.type));
+	memset(&rhash, 0, sizeof(rhash));
+
+	strscpy(rhash.type, "ahash", sizeof(rhash.type));
 
 	rhash.blocksize = alg->cra_blocksize;
 	rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
-		    sizeof(struct crypto_report_hash), &rhash))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash);
 }
 #else
 static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/akcipher.c b/crypto/akcipher.c
index cfbdb06d8ca86..0cbeae137e0ae 100644
--- a/crypto/akcipher.c
+++ b/crypto/akcipher.c
@@ -30,15 +30,12 @@  static int crypto_akcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_akcipher rakcipher;
 
-	strncpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
+	memset(&rakcipher, 0, sizeof(rakcipher));
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_AKCIPHER,
-		    sizeof(struct crypto_report_akcipher), &rakcipher))
-		goto nla_put_failure;
-	return 0;
+	strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
 
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_AKCIPHER,
+		       sizeof(rakcipher), &rakcipher);
 }
 #else
 static int crypto_akcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/blkcipher.c b/crypto/blkcipher.c
index f93abf13b5d42..193237514e902 100644
--- a/crypto/blkcipher.c
+++ b/crypto/blkcipher.c
@@ -507,23 +507,19 @@  static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_blkcipher rblkcipher;
 
-	strncpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type));
-	strncpy(rblkcipher.geniv, alg->cra_blkcipher.geniv ?: "<default>",
+	memset(&rblkcipher, 0, sizeof(rblkcipher));
+
+	strscpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type));
+	strscpy(rblkcipher.geniv, alg->cra_blkcipher.geniv ?: "<default>",
 		sizeof(rblkcipher.geniv));
-	rblkcipher.geniv[sizeof(rblkcipher.geniv) - 1] = '\0';
 
 	rblkcipher.blocksize = alg->cra_blocksize;
 	rblkcipher.min_keysize = alg->cra_blkcipher.min_keysize;
 	rblkcipher.max_keysize = alg->cra_blkcipher.max_keysize;
 	rblkcipher.ivsize = alg->cra_blkcipher.ivsize;
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
-		    sizeof(struct crypto_report_blkcipher), &rblkcipher))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
+		       sizeof(rblkcipher), &rblkcipher);
 }
 #else
 static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/crypto_user_base.c b/crypto/crypto_user_base.c
index 1ecd9b08e38f4..7021efbb35a1e 100644
--- a/crypto/crypto_user_base.c
+++ b/crypto/crypto_user_base.c
@@ -84,42 +84,38 @@  static int crypto_report_cipher(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_cipher rcipher;
 
-	strncpy(rcipher.type, "cipher", sizeof(rcipher.type));
+	memset(&rcipher, 0, sizeof(rcipher));
+
+	strscpy(rcipher.type, "cipher", sizeof(rcipher.type));
 
 	rcipher.blocksize = alg->cra_blocksize;
 	rcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
 	rcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
-		    sizeof(struct crypto_report_cipher), &rcipher))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
+		       sizeof(rcipher), &rcipher);
 }
 
 static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_comp rcomp;
 
-	strncpy(rcomp.type, "compression", sizeof(rcomp.type));
-	if (nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
-		    sizeof(struct crypto_report_comp), &rcomp))
-		goto nla_put_failure;
-	return 0;
+	memset(&rcomp, 0, sizeof(rcomp));
 
-nla_put_failure:
-	return -EMSGSIZE;
+	strscpy(rcomp.type, "compression", sizeof(rcomp.type));
+
+	return nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS, sizeof(rcomp), &rcomp);
 }
 
 static int crypto_report_one(struct crypto_alg *alg,
 			     struct crypto_user_alg *ualg, struct sk_buff *skb)
 {
-	strncpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
-	strncpy(ualg->cru_driver_name, alg->cra_driver_name,
+	memset(ualg, 0, sizeof(*ualg));
+
+	strscpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
+	strscpy(ualg->cru_driver_name, alg->cra_driver_name,
 		sizeof(ualg->cru_driver_name));
-	strncpy(ualg->cru_module_name, module_name(alg->cra_module),
+	strscpy(ualg->cru_module_name, module_name(alg->cra_module),
 		sizeof(ualg->cru_module_name));
 
 	ualg->cru_type = 0;
@@ -132,9 +128,9 @@  static int crypto_report_one(struct crypto_alg *alg,
 	if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
 		struct crypto_report_larval rl;
 
-		strncpy(rl.type, "larval", sizeof(rl.type));
-		if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL,
-			    sizeof(struct crypto_report_larval), &rl))
+		memset(&rl, 0, sizeof(rl));
+		strscpy(rl.type, "larval", sizeof(rl.type));
+		if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL, sizeof(rl), &rl))
 			goto nla_put_failure;
 		goto out;
 	}
diff --git a/crypto/crypto_user_stat.c b/crypto/crypto_user_stat.c
index 1dfaa0ccd555b..a6fb2e6f618df 100644
--- a/crypto/crypto_user_stat.c
+++ b/crypto/crypto_user_stat.c
@@ -39,7 +39,7 @@  static int crypto_report_aead(struct sk_buff *skb, struct crypto_alg *alg)
 
 	memset(&raead, 0, sizeof(raead));
 
-	strncpy(raead.type, "aead", sizeof(raead.type));
+	strscpy(raead.type, "aead", sizeof(raead.type));
 
 	v32 = atomic_read(&alg->encrypt_cnt);
 	raead.stat_encrypt_cnt = v32;
@@ -52,13 +52,7 @@  static int crypto_report_aead(struct sk_buff *skb, struct crypto_alg *alg)
 	v32 = atomic_read(&alg->aead_err_cnt);
 	raead.stat_aead_err_cnt = v32;
 
-	if (nla_put(skb, CRYPTOCFGA_STAT_AEAD,
-		    sizeof(struct crypto_stat), &raead))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_STAT_AEAD, sizeof(raead), &raead);
 }
 
 static int crypto_report_cipher(struct sk_buff *skb, struct crypto_alg *alg)
@@ -69,7 +63,7 @@  static int crypto_report_cipher(struct sk_buff *skb, struct crypto_alg *alg)
 
 	memset(&rcipher, 0, sizeof(rcipher));
 
-	strlcpy(rcipher.type, "cipher", sizeof(rcipher.type));
+	strscpy(rcipher.type, "cipher", sizeof(rcipher.type));
 
 	v32 = atomic_read(&alg->encrypt_cnt);
 	rcipher.stat_encrypt_cnt = v32;
@@ -82,13 +76,7 @@  static int crypto_report_cipher(struct sk_buff *skb, struct crypto_alg *alg)
 	v32 = atomic_read(&alg->cipher_err_cnt);
 	rcipher.stat_cipher_err_cnt = v32;
 
-	if (nla_put(skb, CRYPTOCFGA_STAT_CIPHER,
-		    sizeof(struct crypto_stat), &rcipher))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_STAT_CIPHER, sizeof(rcipher), &rcipher);
 }
 
 static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg)
@@ -99,7 +87,7 @@  static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg)
 
 	memset(&rcomp, 0, sizeof(rcomp));
 
-	strlcpy(rcomp.type, "compression", sizeof(rcomp.type));
+	strscpy(rcomp.type, "compression", sizeof(rcomp.type));
 	v32 = atomic_read(&alg->compress_cnt);
 	rcomp.stat_compress_cnt = v32;
 	v64 = atomic64_read(&alg->compress_tlen);
@@ -111,13 +99,7 @@  static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg)
 	v32 = atomic_read(&alg->cipher_err_cnt);
 	rcomp.stat_compress_err_cnt = v32;
 
-	if (nla_put(skb, CRYPTOCFGA_STAT_COMPRESS,
-		    sizeof(struct crypto_stat), &rcomp))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_STAT_COMPRESS, sizeof(rcomp), &rcomp);
 }
 
 static int crypto_report_acomp(struct sk_buff *skb, struct crypto_alg *alg)
@@ -128,7 +110,7 @@  static int crypto_report_acomp(struct sk_buff *skb, struct crypto_alg *alg)
 
 	memset(&racomp, 0, sizeof(racomp));
 
-	strlcpy(racomp.type, "acomp", sizeof(racomp.type));
+	strscpy(racomp.type, "acomp", sizeof(racomp.type));
 	v32 = atomic_read(&alg->compress_cnt);
 	racomp.stat_compress_cnt = v32;
 	v64 = atomic64_read(&alg->compress_tlen);
@@ -140,13 +122,7 @@  static int crypto_report_acomp(struct sk_buff *skb, struct crypto_alg *alg)
 	v32 = atomic_read(&alg->cipher_err_cnt);
 	racomp.stat_compress_err_cnt = v32;
 
-	if (nla_put(skb, CRYPTOCFGA_STAT_ACOMP,
-		    sizeof(struct crypto_stat), &racomp))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_STAT_ACOMP, sizeof(racomp), &racomp);
 }
 
 static int crypto_report_akcipher(struct sk_buff *skb, struct crypto_alg *alg)
@@ -157,7 +133,7 @@  static int crypto_report_akcipher(struct sk_buff *skb, struct crypto_alg *alg)
 
 	memset(&rakcipher, 0, sizeof(rakcipher));
 
-	strncpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
+	strscpy(rakcipher.type, "akcipher", sizeof(rakcipher.type));
 	v32 = atomic_read(&alg->encrypt_cnt);
 	rakcipher.stat_encrypt_cnt = v32;
 	v64 = atomic64_read(&alg->encrypt_tlen);
@@ -173,13 +149,8 @@  static int crypto_report_akcipher(struct sk_buff *skb, struct crypto_alg *alg)
 	v32 = atomic_read(&alg->akcipher_err_cnt);
 	rakcipher.stat_akcipher_err_cnt = v32;
 
-	if (nla_put(skb, CRYPTOCFGA_STAT_AKCIPHER,
-		    sizeof(struct crypto_stat), &rakcipher))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_STAT_AKCIPHER,
+		       sizeof(rakcipher), &rakcipher);
 }
 
 static int crypto_report_kpp(struct sk_buff *skb, struct crypto_alg *alg)
@@ -189,7 +160,7 @@  static int crypto_report_kpp(struct sk_buff *skb, struct crypto_alg *alg)
 
 	memset(&rkpp, 0, sizeof(rkpp));
 
-	strlcpy(rkpp.type, "kpp", sizeof(rkpp.type));
+	strscpy(rkpp.type, "kpp", sizeof(rkpp.type));
 
 	v = atomic_read(&alg->setsecret_cnt);
 	rkpp.stat_setsecret_cnt = v;
@@ -200,13 +171,7 @@  static int crypto_report_kpp(struct sk_buff *skb, struct crypto_alg *alg)
 	v = atomic_read(&alg->kpp_err_cnt);
 	rkpp.stat_kpp_err_cnt = v;
 
-	if (nla_put(skb, CRYPTOCFGA_STAT_KPP,
-		    sizeof(struct crypto_stat), &rkpp))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_STAT_KPP, sizeof(rkpp), &rkpp);
 }
 
 static int crypto_report_ahash(struct sk_buff *skb, struct crypto_alg *alg)
@@ -217,7 +182,7 @@  static int crypto_report_ahash(struct sk_buff *skb, struct crypto_alg *alg)
 
 	memset(&rhash, 0, sizeof(rhash));
 
-	strncpy(rhash.type, "ahash", sizeof(rhash.type));
+	strscpy(rhash.type, "ahash", sizeof(rhash.type));
 
 	v32 = atomic_read(&alg->hash_cnt);
 	rhash.stat_hash_cnt = v32;
@@ -226,13 +191,7 @@  static int crypto_report_ahash(struct sk_buff *skb, struct crypto_alg *alg)
 	v32 = atomic_read(&alg->hash_err_cnt);
 	rhash.stat_hash_err_cnt = v32;
 
-	if (nla_put(skb, CRYPTOCFGA_STAT_HASH,
-		    sizeof(struct crypto_stat), &rhash))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_STAT_HASH, sizeof(rhash), &rhash);
 }
 
 static int crypto_report_shash(struct sk_buff *skb, struct crypto_alg *alg)
@@ -243,7 +202,7 @@  static int crypto_report_shash(struct sk_buff *skb, struct crypto_alg *alg)
 
 	memset(&rhash, 0, sizeof(rhash));
 
-	strncpy(rhash.type, "shash", sizeof(rhash.type));
+	strscpy(rhash.type, "shash", sizeof(rhash.type));
 
 	v32 = atomic_read(&alg->hash_cnt);
 	rhash.stat_hash_cnt = v32;
@@ -252,13 +211,7 @@  static int crypto_report_shash(struct sk_buff *skb, struct crypto_alg *alg)
 	v32 = atomic_read(&alg->hash_err_cnt);
 	rhash.stat_hash_err_cnt = v32;
 
-	if (nla_put(skb, CRYPTOCFGA_STAT_HASH,
-		    sizeof(struct crypto_stat), &rhash))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_STAT_HASH, sizeof(rhash), &rhash);
 }
 
 static int crypto_report_rng(struct sk_buff *skb, struct crypto_alg *alg)
@@ -269,7 +222,7 @@  static int crypto_report_rng(struct sk_buff *skb, struct crypto_alg *alg)
 
 	memset(&rrng, 0, sizeof(rrng));
 
-	strncpy(rrng.type, "rng", sizeof(rrng.type));
+	strscpy(rrng.type, "rng", sizeof(rrng.type));
 
 	v32 = atomic_read(&alg->generate_cnt);
 	rrng.stat_generate_cnt = v32;
@@ -280,13 +233,7 @@  static int crypto_report_rng(struct sk_buff *skb, struct crypto_alg *alg)
 	v32 = atomic_read(&alg->hash_err_cnt);
 	rrng.stat_rng_err_cnt = v32;
 
-	if (nla_put(skb, CRYPTOCFGA_STAT_RNG,
-		    sizeof(struct crypto_stat), &rrng))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_STAT_RNG, sizeof(rrng), &rrng);
 }
 
 static int crypto_reportstat_one(struct crypto_alg *alg,
@@ -295,10 +242,10 @@  static int crypto_reportstat_one(struct crypto_alg *alg,
 {
 	memset(ualg, 0, sizeof(*ualg));
 
-	strlcpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
-	strlcpy(ualg->cru_driver_name, alg->cra_driver_name,
+	strscpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
+	strscpy(ualg->cru_driver_name, alg->cra_driver_name,
 		sizeof(ualg->cru_driver_name));
-	strlcpy(ualg->cru_module_name, module_name(alg->cra_module),
+	strscpy(ualg->cru_module_name, module_name(alg->cra_module),
 		sizeof(ualg->cru_module_name));
 
 	ualg->cru_type = 0;
@@ -312,9 +259,8 @@  static int crypto_reportstat_one(struct crypto_alg *alg,
 		struct crypto_stat rl;
 
 		memset(&rl, 0, sizeof(rl));
-		strlcpy(rl.type, "larval", sizeof(rl.type));
-		if (nla_put(skb, CRYPTOCFGA_STAT_LARVAL,
-			    sizeof(struct crypto_stat), &rl))
+		strscpy(rl.type, "larval", sizeof(rl.type));
+		if (nla_put(skb, CRYPTOCFGA_STAT_LARVAL, sizeof(rl), &rl))
 			goto nla_put_failure;
 		goto out;
 	}
diff --git a/crypto/kpp.c b/crypto/kpp.c
index a90edc27af77e..bc2f1006a2f77 100644
--- a/crypto/kpp.c
+++ b/crypto/kpp.c
@@ -30,15 +30,11 @@  static int crypto_kpp_report(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_kpp rkpp;
 
-	strncpy(rkpp.type, "kpp", sizeof(rkpp.type));
+	memset(&rkpp, 0, sizeof(rkpp));
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_KPP,
-		    sizeof(struct crypto_report_kpp), &rkpp))
-		goto nla_put_failure;
-	return 0;
+	strscpy(rkpp.type, "kpp", sizeof(rkpp.type));
 
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_KPP, sizeof(rkpp), &rkpp);
 }
 #else
 static int crypto_kpp_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/rng.c b/crypto/rng.c
index 547f16ecbfb03..2406501b90b70 100644
--- a/crypto/rng.c
+++ b/crypto/rng.c
@@ -74,17 +74,13 @@  static int crypto_rng_report(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_rng rrng;
 
-	strncpy(rrng.type, "rng", sizeof(rrng.type));
+	memset(&rrng, 0, sizeof(rrng));
 
-	rrng.seedsize = seedsize(alg);
+	strscpy(rrng.type, "rng", sizeof(rrng.type));
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_RNG,
-		    sizeof(struct crypto_report_rng), &rrng))
-		goto nla_put_failure;
-	return 0;
+	rrng.seedsize = seedsize(alg);
 
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_RNG, sizeof(rrng), &rrng);
 }
 #else
 static int crypto_rng_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/scompress.c b/crypto/scompress.c
index 968bbcf65c941..6f8305f8c3004 100644
--- a/crypto/scompress.c
+++ b/crypto/scompress.c
@@ -40,15 +40,12 @@  static int crypto_scomp_report(struct sk_buff *skb, struct crypto_alg *alg)
 {
 	struct crypto_report_comp rscomp;
 
-	strncpy(rscomp.type, "scomp", sizeof(rscomp.type));
+	memset(&rscomp, 0, sizeof(rscomp));
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
-		    sizeof(struct crypto_report_comp), &rscomp))
-		goto nla_put_failure;
-	return 0;
+	strscpy(rscomp.type, "scomp", sizeof(rscomp.type));
 
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS,
+		       sizeof(rscomp), &rscomp);
 }
 #else
 static int crypto_scomp_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/shash.c b/crypto/shash.c
index d21f04d70dce4..44d297b82a8fb 100644
--- a/crypto/shash.c
+++ b/crypto/shash.c
@@ -408,18 +408,14 @@  static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
 	struct crypto_report_hash rhash;
 	struct shash_alg *salg = __crypto_shash_alg(alg);
 
-	strncpy(rhash.type, "shash", sizeof(rhash.type));
+	memset(&rhash, 0, sizeof(rhash));
+
+	strscpy(rhash.type, "shash", sizeof(rhash.type));
 
 	rhash.blocksize = alg->cra_blocksize;
 	rhash.digestsize = salg->digestsize;
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
-		    sizeof(struct crypto_report_hash), &rhash))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash);
 }
 #else
 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
diff --git a/crypto/skcipher.c b/crypto/skcipher.c
index 4caab81d2d02b..17be8d9c714eb 100644
--- a/crypto/skcipher.c
+++ b/crypto/skcipher.c
@@ -897,21 +897,18 @@  static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
 	struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
 						     base);
 
-	strncpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
-	strncpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
+	memset(&rblkcipher, 0, sizeof(rblkcipher));
+
+	strscpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
+	strscpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
 
 	rblkcipher.blocksize = alg->cra_blocksize;
 	rblkcipher.min_keysize = skcipher->min_keysize;
 	rblkcipher.max_keysize = skcipher->max_keysize;
 	rblkcipher.ivsize = skcipher->ivsize;
 
-	if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
-		    sizeof(struct crypto_report_blkcipher), &rblkcipher))
-		goto nla_put_failure;
-	return 0;
-
-nla_put_failure:
-	return -EMSGSIZE;
+	return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
+		       sizeof(rblkcipher), &rblkcipher);
 }
 #else
 static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)