From 8623faa422c3659903bdb5d19eb8947579e6141f Mon Sep 17 00:00:00 2001 From: Alan Coopersmith Date: Wed, 22 Jan 2014 21:11:16 -0800 Subject: dix: integer overflow in ProcPutImage() [CVE-2014-8092 1/4] ProcPutImage() calculates a length field from a width, left pad and depth specified by the client (if the specified format is XYPixmap). The calculations for the total amount of memory the server needs for the pixmap can overflow a 32-bit number, causing out-of-bounds memory writes on 32-bit systems (since the length is stored in a long int variable). v2: backport to nx-libs 3.6.x (Mike DePaulo) v3: port to NXdispatch.c rather than dispatch.c (Mike DePaulo) Reported-by: Ilja Van Sprundel Signed-off-by: Alan Coopersmith Reviewed-by: Peter Hutterer Conflicts: dix/dispatch.c --- nx-X11/programs/Xserver/hw/nxagent/NXdispatch.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'nx-X11') diff --git a/nx-X11/programs/Xserver/hw/nxagent/NXdispatch.c b/nx-X11/programs/Xserver/hw/nxagent/NXdispatch.c index 3d9ee8c7f..e5bec8aba 100644 --- a/nx-X11/programs/Xserver/hw/nxagent/NXdispatch.c +++ b/nx-X11/programs/Xserver/hw/nxagent/NXdispatch.c @@ -2618,7 +2618,9 @@ ProcPutImage(register ClientPtr client) tmpImage = (char *)&stuff[1]; lengthProto = length; - + if (lengthProto >= (INT32_MAX / stuff->height)) + return BadLength; + if (((((lengthProto * stuff->height) + (unsigned)3) >> 2) + (sizeof(xPutImageReq) >> 2)) != client->req_len) return BadLength; -- cgit v1.2.3