From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53809) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1drjNQ-0002zO-J3 for qemu-devel@nongnu.org; Tue, 12 Sep 2017 07:29:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1drjNP-0004RH-GG for qemu-devel@nongnu.org; Tue, 12 Sep 2017 07:29:12 -0400 From: "Daniel P. Berrange" Date: Tue, 12 Sep 2017 12:28:51 +0100 Message-Id: <20170912112855.24269-4-berrange@redhat.com> In-Reply-To: <20170912112855.24269-1-berrange@redhat.com> References: <20170912112855.24269-1-berrange@redhat.com> Subject: [Qemu-devel] [PATCH v3 3/7] block: fix data type casting for crypto payload offset List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, Kevin Wolf , Max Reitz , Eric Blake , Stefan Hajnoczi , "Daniel P. Berrange" The crypto APIs report the offset of the data payload as an uint64_t type, but the block driver is casting to size_t or ssize_t which will potentially truncate. Most of the block APIs use int64_t for offsets meanwhile, so even if using uint64_t in the crypto block driver we are still at risk of truncation. Change the block crypto driver to use uint64_t, but add asserts that the value is less than INT64_MAX. Signed-off-by: Daniel P. Berrange --- block/crypto.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/block/crypto.c b/block/crypto.c index cc8afe0e0d..d68cbac2ac 100644 --- a/block/crypto.c +++ b/block/crypto.c @@ -364,8 +364,9 @@ static int block_crypto_truncate(BlockDriverState *bs, int64_t offset, PreallocMode prealloc, Error **errp) { BlockCrypto *crypto = bs->opaque; - size_t payload_offset = + uint64_t payload_offset = qcrypto_block_get_payload_offset(crypto->block); + assert(payload_offset < (INT64_MAX - offset)); offset += payload_offset; @@ -391,8 +392,9 @@ block_crypto_co_readv(BlockDriverState *bs, int64_t sector_num, uint8_t *cipher_data = NULL; QEMUIOVector hd_qiov; int ret = 0; - size_t payload_offset = + uint64_t payload_offset = qcrypto_block_get_payload_offset(crypto->block) / 512; + assert(payload_offset < (INT64_MAX / 512)); qemu_iovec_init(&hd_qiov, qiov->niov); @@ -458,8 +460,9 @@ block_crypto_co_writev(BlockDriverState *bs, int64_t sector_num, uint8_t *cipher_data = NULL; QEMUIOVector hd_qiov; int ret = 0; - size_t payload_offset = + uint64_t payload_offset = qcrypto_block_get_payload_offset(crypto->block) / 512; + assert(payload_offset < (INT64_MAX / 512)); qemu_iovec_init(&hd_qiov, qiov->niov); @@ -520,7 +523,9 @@ static int64_t block_crypto_getlength(BlockDriverState *bs) BlockCrypto *crypto = bs->opaque; int64_t len = bdrv_getlength(bs->file->bs); - ssize_t offset = qcrypto_block_get_payload_offset(crypto->block); + uint64_t offset = qcrypto_block_get_payload_offset(crypto->block); + assert(offset < INT64_MAX); + assert(offset < len); len -= offset; -- 2.13.5