From 702e709973252d596be736c2f5c0de4837446501 Mon Sep 17 00:00:00 2001 From: Matthieu Herrb Date: Sun, 8 Jun 2008 11:15:39 -0600 Subject: CVE-2008-2362 - RENDER Extension memory corruption Integer overflows can occur in the code validating the parameters for the SProcRenderCreateLinearGradient, SProcRenderCreateRadialGradient and SProcRenderCreateConicalGradient functions, leading to memory corruption by swapping bytes outside of the intended request parameters. --- render/render.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/render/render.c b/render/render.c index 74c5f6387..b53e878bd 100644 --- a/render/render.c +++ b/render/render.c @@ -1920,6 +1920,8 @@ static int ProcRenderCreateLinearGradient (ClientPtr client) LEGAL_NEW_RESOURCE(stuff->pid, client); len = (client->req_len << 2) - sizeof(xRenderCreateLinearGradientReq); + if (stuff->nStops > UINT32_MAX/(sizeof(xFixed) + sizeof(xRenderColor))) + return BadLength; if (len != stuff->nStops*(sizeof(xFixed) + sizeof(xRenderColor))) return BadLength; @@ -2493,18 +2495,18 @@ SProcRenderCreateSolidFill(ClientPtr client) return (*ProcRenderVector[stuff->renderReqType]) (client); } -static void swapStops(void *stuff, int n) +static void swapStops(void *stuff, int num) { - int i; + int i, n; CARD32 *stops; CARD16 *colors; stops = (CARD32 *)(stuff); - for (i = 0; i < n; ++i) { + for (i = 0; i < num; ++i) { swapl(stops, n); ++stops; } colors = (CARD16 *)(stops); - for (i = 0; i < 4*n; ++i) { + for (i = 0; i < 4*num; ++i) { swaps(stops, n); ++stops; } @@ -2527,6 +2529,8 @@ SProcRenderCreateLinearGradient (ClientPtr client) swapl(&stuff->nStops, n); len = (client->req_len << 2) - sizeof(xRenderCreateLinearGradientReq); + if (stuff->nStops > UINT32_MAX/(sizeof(xFixed) + sizeof(xRenderColor))) + return BadLength; if (len != stuff->nStops*(sizeof(xFixed) + sizeof(xRenderColor))) return BadLength; @@ -2554,6 +2558,8 @@ SProcRenderCreateRadialGradient (ClientPtr client) swapl(&stuff->nStops, n); len = (client->req_len << 2) - sizeof(xRenderCreateRadialGradientReq); + if (stuff->nStops > UINT32_MAX/(sizeof(xFixed) + sizeof(xRenderColor))) + return BadLength; if (len != stuff->nStops*(sizeof(xFixed) + sizeof(xRenderColor))) return BadLength; @@ -2578,6 +2584,8 @@ SProcRenderCreateConicalGradient (ClientPtr client) swapl(&stuff->nStops, n); len = (client->req_len << 2) - sizeof(xRenderCreateConicalGradientReq); + if (stuff->nStops > UINT32_MAX/(sizeof(xFixed) + sizeof(xRenderColor))) + return BadLength; if (len != stuff->nStops*(sizeof(xFixed) + sizeof(xRenderColor))) return BadLength; -- cgit v1.2.3