From 9171206db349a0c6fda719746be0b15049d57aaa Mon Sep 17 00:00:00 2001 From: Matthieu Herrb Date: Tue, 10 Jun 2008 12:23:03 -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(-) (limited to 'render') diff --git a/render/render.c b/render/render.c index 7787e18ae..638aa46a3 100644 --- a/render/render.c +++ b/render/render.c @@ -1996,6 +1996,8 @@ 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; @@ -2584,18 +2586,18 @@ 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; } @@ -2618,6 +2620,8 @@ 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; @@ -2645,6 +2649,8 @@ 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; @@ -2669,6 +2675,8 @@ 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