Fix CVE-2017-5931 (integer overflow in handling virtio-crypto requests): http://seclists.org/oss-sec/2017/q1/337 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5931 Patch copied from upstream source repository: http://git.qemu-project.org/?p=qemu.git;a=commit;h=a08aaff811fb194950f79711d2afe5a892ae03a4 From a08aaff811fb194950f79711d2afe5a892ae03a4 Mon Sep 17 00:00:00 2001 From: Gonglei Date: Tue, 3 Jan 2017 14:50:03 +0800 Subject: [PATCH] virtio-crypto: fix possible integer and heap overflow Because the 'size_t' type is 4 bytes in 32-bit platform, which is the same with 'int'. It's easy to make 'max_len' to zero when integer overflow and then cause heap overflow if 'max_len' is zero. Using uint_64 instead of size_t to avoid the integer overflow. Cc: qemu-stable@nongnu.org Reported-by: Li Qiang Signed-off-by: Gonglei Tested-by: Li Qiang Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/virtio/virtio-crypto.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c index 2f2467e859..c23e1ad458 100644 --- a/hw/virtio/virtio-crypto.c +++ b/hw/virtio/virtio-crypto.c @@ -416,7 +416,7 @@ virtio_crypto_sym_op_helper(VirtIODevice *vdev, uint32_t hash_start_src_offset = 0, len_to_hash = 0; uint32_t cipher_start_src_offset = 0, len_to_cipher = 0; - size_t max_len, curr_size = 0; + uint64_t max_len, curr_size = 0; size_t s; /* Plain cipher */ @@ -441,7 +441,7 @@ virtio_crypto_sym_op_helper(VirtIODevice *vdev, return NULL; } - max_len = iv_len + aad_len + src_len + dst_len + hash_result_len; + max_len = (uint64_t)iv_len + aad_len + src_len + dst_len + hash_result_len; if (unlikely(max_len > vcrypto->conf.max_size)) { virtio_error(vdev, "virtio-crypto too big length"); return NULL; -- 2.11.1