From c1d8634c207defb547a57515729233e47f65718f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= Date: Tue, 10 May 2022 14:17:43 +0100 Subject: [PATCH] crypto: sanity check that LUKS header strings are NUL-terminated MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The LUKS spec requires that header strings are NUL-terminated, and our code relies on that. Protect against maliciously crafted headers by adding validation. Reviewed-by: Richard W.M. Jones Signed-off-by: Daniel P. Berrangé --- crypto/block-luks.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/crypto/block-luks.c b/crypto/block-luks.c index f62be6836b..27d1b34c1d 100644 --- a/crypto/block-luks.c +++ b/crypto/block-luks.c @@ -554,6 +554,24 @@ qcrypto_block_luks_check_header(const QCryptoBlockLUKS *luks, Error **errp) return -1; } + if (!memchr(luks->header.cipher_name, '\0', + sizeof(luks->header.cipher_name))) { + error_setg(errp, "LUKS header cipher name is not NUL terminated"); + return -1; + } + + if (!memchr(luks->header.cipher_mode, '\0', + sizeof(luks->header.cipher_mode))) { + error_setg(errp, "LUKS header cipher mode is not NUL terminated"); + return -1; + } + + if (!memchr(luks->header.hash_spec, '\0', + sizeof(luks->header.hash_spec))) { + error_setg(errp, "LUKS header hash spec is not NUL terminated"); + return -1; + } + /* Check all keyslots for corruption */ for (i = 0 ; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS ; i++) {