lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 08 Jan 2020 19:43:03 +0000 From: Ben Hutchings <ben@...adent.org.uk> To: linux-kernel@...r.kernel.org, stable@...r.kernel.org CC: akpm@...ux-foundation.org, Denis Kirjanov <kda@...ux-powerpc.org>, linux-crypto@...r.kernel.org, "Eric Biggers" <ebiggers@...gle.com> Subject: [PATCH 3.16 05/63] crypto: cts - fix crash on short inputs 3.16.81-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Eric Biggers <ebiggers@...gle.com> In the CTS template, when the input length is <= one block cipher block (e.g. <= 16 bytes for AES) pass the correct length to the underlying CBC transform rather than one block. This matches the upstream behavior and makes the encryption/decryption operation correctly return -EINVAL when 1 <= nbytes < bsize or succeed when nbytes == 0, rather than crashing. This was fixed upstream incidentally by a large refactoring, commit 0605c41cc53c ("crypto: cts - Convert to skcipher"). But syzkaller easily trips over this when running on older kernels, as it's easily reachable via AF_ALG. Therefore, this patch makes the minimal fix for older kernels. Cc: linux-crypto@...r.kernel.org Fixes: 76cb9521795a ("[CRYPTO] cts: Add CTS mode required for Kerberos AES support") Signed-off-by: Eric Biggers <ebiggers@...gle.com> Signed-off-by: Ben Hutchings <ben@...adent.org.uk> --- crypto/cts.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/crypto/cts.c +++ b/crypto/cts.c @@ -137,8 +137,8 @@ static int crypto_cts_encrypt(struct blk lcldesc.info = desc->info; lcldesc.flags = desc->flags; - if (tot_blocks == 1) { - err = crypto_blkcipher_encrypt_iv(&lcldesc, dst, src, bsize); + if (tot_blocks <= 1) { + err = crypto_blkcipher_encrypt_iv(&lcldesc, dst, src, nbytes); } else if (nbytes <= bsize * 2) { err = cts_cbc_encrypt(ctx, desc, dst, src, 0, nbytes); } else { @@ -232,8 +232,8 @@ static int crypto_cts_decrypt(struct blk lcldesc.info = desc->info; lcldesc.flags = desc->flags; - if (tot_blocks == 1) { - err = crypto_blkcipher_decrypt_iv(&lcldesc, dst, src, bsize); + if (tot_blocks <= 1) { + err = crypto_blkcipher_decrypt_iv(&lcldesc, dst, src, nbytes); } else if (nbytes <= bsize * 2) { err = cts_cbc_decrypt(ctx, desc, dst, src, 0, nbytes); } else {
Powered by blists - more mailing lists