Backport patch to fix CVE-2021-4009. CVE: CVE-2021-4009 Upstream-Status: Backport [https://gitlab.freedesktop.org/xorg/xserver/-/commit/b519675] Signed-off-by: Kai Kang From b5196750099ae6ae582e1f46bd0a6dad29550e02 Mon Sep 17 00:00:00 2001 From: Povilas Kanapickas Date: Tue, 14 Dec 2021 15:00:01 +0200 Subject: [PATCH] xfixes: Fix out of bounds access in *ProcXFixesCreatePointerBarrier() ZDI-CAN-14950, CVE-2021-4009 This vulnerability was discovered and the fix was suggested by: Jan-Niklas Sohn working with Trend Micro Zero Day Initiative Signed-off-by: Povilas Kanapickas --- xfixes/cursor.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/xfixes/cursor.c b/xfixes/cursor.c index 60580b88f..c5d4554b2 100644 --- a/xfixes/cursor.c +++ b/xfixes/cursor.c @@ -1010,7 +1010,8 @@ ProcXFixesCreatePointerBarrier(ClientPtr client) { REQUEST(xXFixesCreatePointerBarrierReq); - REQUEST_FIXED_SIZE(xXFixesCreatePointerBarrierReq, pad_to_int32(stuff->num_devices)); + REQUEST_FIXED_SIZE(xXFixesCreatePointerBarrierReq, + pad_to_int32(stuff->num_devices * sizeof(CARD16))); LEGAL_NEW_RESOURCE(stuff->barrier, client); return XICreatePointerBarrier(client, stuff); @@ -1027,7 +1028,8 @@ SProcXFixesCreatePointerBarrier(ClientPtr client) swaps(&stuff->length); swaps(&stuff->num_devices); - REQUEST_FIXED_SIZE(xXFixesCreatePointerBarrierReq, pad_to_int32(stuff->num_devices)); + REQUEST_FIXED_SIZE(xXFixesCreatePointerBarrierReq, + pad_to_int32(stuff->num_devices * sizeof(CARD16))); swapl(&stuff->barrier); swapl(&stuff->window); -- GitLab