[PATCH v8 2/9] crypto: cbc: Remove VLA usage
From: Kees Cook
Date: Tue Aug 07 2018 - 17:19:27 EST
In the quest to remove all stack VLA usage from the kernel[1], this
uses the upper bounds on blocksize. Since this is always a cipher
blocksize, use the existing cipher max blocksize.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@xxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
include/crypto/cbc.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/crypto/cbc.h b/include/crypto/cbc.h
index f5b8bfc22e6d..3bf28beefa33 100644
--- a/include/crypto/cbc.h
+++ b/include/crypto/cbc.h
@@ -113,7 +113,7 @@ static inline int crypto_cbc_decrypt_inplace(
unsigned int bsize = crypto_skcipher_blocksize(tfm);
unsigned int nbytes = walk->nbytes;
u8 *src = walk->src.virt.addr;
- u8 last_iv[bsize];
+ u8 last_iv[MAX_CIPHER_BLOCKSIZE];
/* Start of the last block. */
src += nbytes - (nbytes & (bsize - 1)) - bsize;
--
2.17.1