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| author | Eric Biggers <ebiggers@google.com> | 2019-01-04 07:16:13 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-03-23 10:19:01 +0300 |
| commit | 51febb43d09ce3085aa386303a816c3179ee7a39 (patch) | |
| tree | 2e48a631279692adc78ff4339556513830e9f4bc | |
| parent | 0ece4f706a10f19492089dce878d865405aa2ec4 (diff) | |
| download | linux-51febb43d09ce3085aa386303a816c3179ee7a39.tar.xz | |
crypto: pcbc - remove bogus memcpy()s with src == dest
commit 251b7aea34ba3c4d4fdfa9447695642eb8b8b098 upstream.
The memcpy()s in the PCBC implementation use walk->iv as both the source
and destination, which has undefined behavior. These memcpy()'s are
actually unneeded, because walk->iv is already used to hold the previous
plaintext block XOR'd with the previous ciphertext block. Thus,
walk->iv is already updated to its final value.
So remove the broken and unnecessary memcpy()s.
Fixes: 91652be5d1b9 ("[CRYPTO] pcbc: Add Propagated CBC template")
Cc: <stable@vger.kernel.org> # v2.6.21+
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Maxim Zhukov <mussitantesmortem@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | crypto/pcbc.c | 14 |
1 files changed, 4 insertions, 10 deletions
diff --git a/crypto/pcbc.c b/crypto/pcbc.c index f654965f0933..de81f716cf26 100644 --- a/crypto/pcbc.c +++ b/crypto/pcbc.c @@ -52,7 +52,7 @@ static int crypto_pcbc_encrypt_segment(struct blkcipher_desc *desc, unsigned int nbytes = walk->nbytes; u8 *src = walk->src.virt.addr; u8 *dst = walk->dst.virt.addr; - u8 *iv = walk->iv; + u8 * const iv = walk->iv; do { crypto_xor(iv, src, bsize); @@ -76,7 +76,7 @@ static int crypto_pcbc_encrypt_inplace(struct blkcipher_desc *desc, int bsize = crypto_cipher_blocksize(tfm); unsigned int nbytes = walk->nbytes; u8 *src = walk->src.virt.addr; - u8 *iv = walk->iv; + u8 * const iv = walk->iv; u8 tmpbuf[bsize]; do { @@ -89,8 +89,6 @@ static int crypto_pcbc_encrypt_inplace(struct blkcipher_desc *desc, src += bsize; } while ((nbytes -= bsize) >= bsize); - memcpy(walk->iv, iv, bsize); - return nbytes; } @@ -130,7 +128,7 @@ static int crypto_pcbc_decrypt_segment(struct blkcipher_desc *desc, unsigned int nbytes = walk->nbytes; u8 *src = walk->src.virt.addr; u8 *dst = walk->dst.virt.addr; - u8 *iv = walk->iv; + u8 * const iv = walk->iv; do { fn(crypto_cipher_tfm(tfm), dst, src); @@ -142,8 +140,6 @@ static int crypto_pcbc_decrypt_segment(struct blkcipher_desc *desc, dst += bsize; } while ((nbytes -= bsize) >= bsize); - memcpy(walk->iv, iv, bsize); - return nbytes; } @@ -156,7 +152,7 @@ static int crypto_pcbc_decrypt_inplace(struct blkcipher_desc *desc, int bsize = crypto_cipher_blocksize(tfm); unsigned int nbytes = walk->nbytes; u8 *src = walk->src.virt.addr; - u8 *iv = walk->iv; + u8 * const iv = walk->iv; u8 tmpbuf[bsize]; do { @@ -169,8 +165,6 @@ static int crypto_pcbc_decrypt_inplace(struct blkcipher_desc *desc, src += bsize; } while ((nbytes -= bsize) >= bsize); - memcpy(walk->iv, iv, bsize); - return nbytes; } |