| From 9362c7ddd1af3b168953d0737877bc52d79c94f4 Mon Sep 17 00:00:00 2001 |
| From: Tobias Stoeckmann <tobias@stoeckmann.org> |
| Date: Sun, 25 Sep 2016 21:43:09 +0200 |
| Subject: Validate lengths while parsing server data. |
| |
| Individual lengths inside received server data can overflow |
| the previously reserved memory. |
| |
| It is therefore important to validate every single length |
| field to not overflow the previously agreed sum of all invidual |
| length fields. |
| |
| v2: consume remaining bytes in the reply buffer on error. |
| |
| CVE: CVE-2016-7949 |
| Upstream-Status: Backport |
| |
| Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org> |
| Reviewed-by: Matthieu Herrb@laas.fr |
| Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com> |
| |
| diff --git a/src/Xrender.c b/src/Xrender.c |
| index 3102eb2..71cf3e6 100644 |
| --- a/src/Xrender.c |
| +++ b/src/Xrender.c |
| @@ -533,12 +533,30 @@ XRenderQueryFormats (Display *dpy) |
| screen->fallback = _XRenderFindFormat (xri, xScreen->fallback); |
| screen->subpixel = SubPixelUnknown; |
| xDepth = (xPictDepth *) (xScreen + 1); |
| + if (screen->ndepths > rep.numDepths) { |
| + Xfree (xri); |
| + Xfree (xData); |
| + _XEatDataWords (dpy, rep.length); |
| + UnlockDisplay (dpy); |
| + SyncHandle (); |
| + return 0; |
| + } |
| + rep.numDepths -= screen->ndepths; |
| for (nd = 0; nd < screen->ndepths; nd++) |
| { |
| depth->depth = xDepth->depth; |
| depth->nvisuals = xDepth->nPictVisuals; |
| depth->visuals = visual; |
| xVisual = (xPictVisual *) (xDepth + 1); |
| + if (depth->nvisuals > rep.numVisuals) { |
| + Xfree (xri); |
| + Xfree (xData); |
| + _XEatDataWords (dpy, rep.length); |
| + UnlockDisplay (dpy); |
| + SyncHandle (); |
| + return 0; |
| + } |
| + rep.numVisuals -= depth->nvisuals; |
| for (nv = 0; nv < depth->nvisuals; nv++) |
| { |
| visual->visual = _XRenderFindVisual (dpy, xVisual->visual); |
| -- |
| cgit v0.10.2 |
| |