From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AEA004746B7; Fri, 7 Aug 2026 15:48:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786117701; cv=none; b=t9/VUlClaRA1IossYNhel83DprikKokS5QnjXVln0Lz/e3wH10oBuJxJF0dTQJ+drlqJ2EOqqcSCCjqCJkZ3itBO4wwlXKD555P5pqqIhff68jdQCHrf7lqZJdCcU1JWOQLYKjD+0emwbIJ2lmBl5RSV2mxodkDmcmaMe6gNCrg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786117701; c=relaxed/simple; bh=IKUfCx57KbE5ZA5LT8tIfrRWse3CXaQ7WwX8Zht+Bsg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dJxBl5ytDFLlwcGmtbSwlLRjGWQuK73cpe8QrJ/UHPsWY01418CNGl1Mxy45H33jMF4vUvhIbBB/zjl2zlgSrr37CoBHy8RItflOOnrOB8zsbRr91mt8NnJeRH4vMfJYPs27x4C445ICZunarIKiMFm0mZbsLEqjpXS0fTTJw/s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=o8EPWrog; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="o8EPWrog" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 067EE1F000E9; Fri, 7 Aug 2026 15:48:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786117700; bh=WiSwArTilISxCCyaObj64Od0uTzm/l/mklpNONAh4Xs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=o8EPWrogEO0o//wPVBrklnnxx8AQjnwNtGS2+zoYRXgtdLWqLqbmr/sS1TS8ohgzo nTsVmV+vTeImMhCpxDgMOqAK+kx3qXkzQHDvN8tZntHmNFxLP2e3Q8j3XmtZg3Sxx3 0iNTv34cTa4vtpFGG7wQKWdv0Twv3NDZc/0O+N4Y= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zack Rusin , Ian Forbes Subject: [PATCH 7.1 412/438] drm/vmwgfx: validate DRAW_PRIMITIVES header size before division Date: Fri, 7 Aug 2026 16:40:08 +0200 Message-ID: <20260807143436.748401862@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260807143428.008222056@linuxfoundation.org> References: <20260807143428.008222056@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Zack Rusin commit 85891d174707d8bddcec7a888fb4e1d17def34f3 upstream. vmw_cmd_draw() computes maxnum = (header->size - sizeof(cmd->body)) / sizeof(*decl); where header->size is u32 and is taken straight from the user-supplied command stream. When header->size is less than sizeof(cmd->body) the unsigned subtraction wraps to nearly 4 GiB, producing a huge maxnum. Any user-controlled cmd->body.numVertexDecls then passes the bound and the loop dereferences decl[i] far past the end of the kernel command bounce buffer, producing an out-of-bounds read of kernel memory. Reject undersized headers up front. Fixes: 7a73ba7469cb ("drm/vmwgfx: Use TTM handles instead of SIDs as user-space surface handles.") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-7-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c @@ -1571,11 +1571,17 @@ static int vmw_cmd_draw(struct vmw_priva uint32_t maxnum; int ret; + cmd = container_of(header, typeof(*cmd), header); + + if (unlikely(header->size < sizeof(cmd->body))) { + VMW_DEBUG_USER("Illegal DRAW_PRIMITIVES header size.\n"); + return -EINVAL; + } + ret = vmw_cmd_cid_check(dev_priv, sw_context, header); if (unlikely(ret != 0)) return ret; - cmd = container_of(header, typeof(*cmd), header); maxnum = (header->size - sizeof(cmd->body)) / sizeof(*decl); if (unlikely(cmd->body.numVertexDecls > maxnum)) {