From: Stafford Horne Subject: [PATCH v2 1/2] crypto: Fix -Wstringop-truncation warnings Date: Mon, 25 Jun 2018 21:45:37 +0900 Message-ID: <20180625124538.21051-2-shorne@gmail.com> References: <20180625124538.21051-1-shorne@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Greg KH , arnd@arndb.de, Eric Biggers , linux-crypto@vger.kernel.org, Stafford Horne , Max Filippov , Nick Desaulniers , Herbert Xu , "David S. Miller" To: LKML Return-path: In-Reply-To: <20180625124538.21051-1-shorne@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org As of GCC 9.0.0 the build is reporting warnings like: crypto/ablkcipher.c: In function ‘crypto_ablkcipher_report’: crypto/ablkcipher.c:374:2: warning: ‘strncpy’ specified bound 64 equals destination size [-Wstringop-truncation] strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "", ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ sizeof(rblkcipher.geniv)); ~~~~~~~~~~~~~~~~~~~~~~~~~ This means the strnycpy might create a non null terminated string. Fix this by explicitly performing '\0' termination. Cc: Greg Kroah-Hartman Cc: Arnd Bergmann Cc: Max Filippov Cc: Eric Biggers Cc: Nick Desaulniers Signed-off-by: Stafford Horne --- crypto/ablkcipher.c | 2 ++ crypto/blkcipher.c | 1 + 2 files changed, 3 insertions(+) diff --git a/crypto/ablkcipher.c b/crypto/ablkcipher.c index d880a4897159..1edb5000d783 100644 --- a/crypto/ablkcipher.c +++ b/crypto/ablkcipher.c @@ -373,6 +373,7 @@ static int crypto_ablkcipher_report(struct sk_buff *skb, struct crypto_alg *alg) strncpy(rblkcipher.type, "ablkcipher", sizeof(rblkcipher.type)); strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "", sizeof(rblkcipher.geniv)); + rblkcipher.geniv[sizeof(rblkcipher.geniv) - 1] = '\0'; rblkcipher.blocksize = alg->cra_blocksize; rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize; @@ -447,6 +448,7 @@ static int crypto_givcipher_report(struct sk_buff *skb, struct crypto_alg *alg) strncpy(rblkcipher.type, "givcipher", sizeof(rblkcipher.type)); strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "", sizeof(rblkcipher.geniv)); + rblkcipher.geniv[sizeof(rblkcipher.geniv) - 1] = '\0'; rblkcipher.blocksize = alg->cra_blocksize; rblkcipher.min_keysize = alg->cra_ablkcipher.min_keysize; diff --git a/crypto/blkcipher.c b/crypto/blkcipher.c index 01c0d4aa2563..dd4dcab3766a 100644 --- a/crypto/blkcipher.c +++ b/crypto/blkcipher.c @@ -512,6 +512,7 @@ static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg) strncpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type)); strncpy(rblkcipher.geniv, alg->cra_blkcipher.geniv ?: "", sizeof(rblkcipher.geniv)); + rblkcipher.geniv[sizeof(rblkcipher.geniv) - 1] = '\0'; rblkcipher.blocksize = alg->cra_blocksize; rblkcipher.min_keysize = alg->cra_blkcipher.min_keysize; -- 2.17.0