From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BFC5BC25B06 for ; Sun, 14 Aug 2022 16:38:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243072AbiHNQiJ (ORCPT ); Sun, 14 Aug 2022 12:38:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243111AbiHNQg0 (ORCPT ); Sun, 14 Aug 2022 12:36:26 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A1A321ADB8; Sun, 14 Aug 2022 09:28:41 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 4F35AB80B37; Sun, 14 Aug 2022 16:28:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 45407C4347C; Sun, 14 Aug 2022 16:28:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1660494519; bh=noI0SHTyTyoNWmj0FmTe9S6Tq2D9OmFbIBtBdSw+lgc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j6JNtLQT7/DCACK25SjLpYQLbXTLy2/dHM/XYr2rnjmf0p/6QPvi4eS5lR3TeMaMq AFY1ti/7PkO2auD6wGXkSserde7lca6i01LvJmEEmsc+ZfV0xlNqrUr3d3ryvuGrKt zbr+bo6HqBMwymb+7VNlYexrOvfxpIdps+jYnCL3AKY5JXQ8AoP/MEoZkgJiQ/7tt/ QtSfczsxGFVQ+y0C8FexLIToSZ8JqR3XSSoJKsEY/RJv6/nGvreOAgKiepIth+UNk/ f70GuiN76D0SQK9z36l1JSQue8S+ks34mVRxx1oHde7zpVn0QyFfYJYSW4cnYNE5Mi lywE8yLxXVuGg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Schspa Shi , Cornelia Huck , Alex Williamson , Sasha Levin , kvm@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 03/16] vfio: Clear the caps->buf to NULL after free Date: Sun, 14 Aug 2022 12:28:18 -0400 Message-Id: <20220814162833.2398478-3-sashal@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220814162833.2398478-1-sashal@kernel.org> References: <20220814162833.2398478-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Schspa Shi [ Upstream commit 6641085e8d7b3f061911517f79a2a15a0a21b97b ] On buffer resize failure, vfio_info_cap_add() will free the buffer, report zero for the size, and return -ENOMEM. As additional hardening, also clear the buffer pointer to prevent any chance of a double free. Signed-off-by: Schspa Shi Reviewed-by: Cornelia Huck Link: https://lore.kernel.org/r/20220629022948.55608-1-schspa@gmail.com Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin --- drivers/vfio/vfio.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 388597930b64..efd3782ead97 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1802,6 +1802,7 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps, buf = krealloc(caps->buf, caps->size + size, GFP_KERNEL); if (!buf) { kfree(caps->buf); + caps->buf = NULL; caps->size = 0; return ERR_PTR(-ENOMEM); } -- 2.35.1