From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56897) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z8UxH-00042M-H0 for qemu-devel@nongnu.org; Fri, 26 Jun 2015 10:50:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z8UxG-0001iz-4d for qemu-devel@nongnu.org; Fri, 26 Jun 2015 10:50:11 -0400 Received: from mail-qk0-x22a.google.com ([2607:f8b0:400d:c09::22a]:35740) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z8UxF-0001hA-Ud for qemu-devel@nongnu.org; Fri, 26 Jun 2015 10:50:10 -0400 Received: by qkbp125 with SMTP id p125so56279131qkb.2 for ; Fri, 26 Jun 2015 07:50:09 -0700 (PDT) From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Date: Fri, 26 Jun 2015 16:49:10 +0200 Message-Id: <1435330185-23248-5-git-send-email-marcandre.lureau@gmail.com> In-Reply-To: <1435330185-23248-1-git-send-email-marcandre.lureau@gmail.com> References: <1435330185-23248-1-git-send-email-marcandre.lureau@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH 04/39] ivshmem: fix number of bytes to push to fifo List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: cam@cs.ualberta.ca, =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , stefanha@redhat.com If the fifo has 0 bytes, and the read is of size 1, the call to fifo8_push_all() will copy out of bounds data. Signed-off-by: Marc-André Lureau --- hw/misc/ivshmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c index fb53b3f..2162d02 100644 --- a/hw/misc/ivshmem.c +++ b/hw/misc/ivshmem.c @@ -455,7 +455,7 @@ static void ivshmem_read(void *opaque, const uint8_t *buf, int size) uint32_t num; IVSHMEM_DPRINTF("short read of %d bytes\n", size); - num = MAX(size, sizeof(long) - fifo8_num_used(&s->incoming_fifo)); + num = MIN(size, sizeof(long) - fifo8_num_used(&s->incoming_fifo)); fifo8_push_all(&s->incoming_fifo, buf, num); if (fifo8_num_used(&s->incoming_fifo) < sizeof(incoming_posn)) { return; -- 2.4.3