From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45722) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gByXI-0004a8-FB for qemu-devel@nongnu.org; Mon, 15 Oct 2018 04:47:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gByXH-0004U8-Pd for qemu-devel@nongnu.org; Mon, 15 Oct 2018 04:47:36 -0400 From: Jason Wang Date: Mon, 15 Oct 2018 16:46:21 +0800 Message-Id: <1539593186-32183-22-git-send-email-jasowang@redhat.com> In-Reply-To: <1539593186-32183-1-git-send-email-jasowang@redhat.com> References: <1539593186-32183-1-git-send-email-jasowang@redhat.com> Subject: [Qemu-devel] [PULL 21/26] ne2000: fix possible out of bound access in ne2000_receive List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: peter.maydell@linaro.org, qemu-devel@nongnu.org Cc: Jason Wang , qemu-stable@nongnu.org In ne2000_receive(), we try to assign size_ to size which converts from size_t to integer. This will cause troubles when size_ is greater INT_MAX, this will lead a negative value in size and it can then pass the check of size < MIN_BUF_SIZE which may lead out of bound access of for both buf and buf1. Fixing by converting the type of size to size_t. CC: qemu-stable@nongnu.org Reported-by: Daniel Shapira Reviewed-by: Michael S. Tsirkin Signed-off-by: Jason Wang --- hw/net/ne2000.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/net/ne2000.c b/hw/net/ne2000.c index 07d79e3..869518e 100644 --- a/hw/net/ne2000.c +++ b/hw/net/ne2000.c @@ -174,7 +174,7 @@ static int ne2000_buffer_full(NE2000State *s) ssize_t ne2000_receive(NetClientState *nc, const uint8_t *buf, size_t size_) { NE2000State *s = qemu_get_nic_opaque(nc); - int size = size_; + size_t size = size_; uint8_t *p; unsigned int total_len, next, avail, len, index, mcast_idx; uint8_t buf1[60]; @@ -182,7 +182,7 @@ ssize_t ne2000_receive(NetClientState *nc, const uint8_t *buf, size_t size_) { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; #if defined(DEBUG_NE2000) - printf("NE2000: received len=%d\n", size); + printf("NE2000: received len=%zu\n", size); #endif if (s->cmd & E8390_STOP || ne2000_buffer_full(s)) -- 2.5.0