From nobody Thu Dec 18 12:43:42 2025 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 9EF83C32772 for ; Tue, 23 Aug 2022 09:23:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349527AbiHWJXH (ORCPT ); Tue, 23 Aug 2022 05:23:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350121AbiHWJV3 (ORCPT ); Tue, 23 Aug 2022 05:21:29 -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 181D78B9B4; Tue, 23 Aug 2022 01:34:23 -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 0E6A0B81C1B; Tue, 23 Aug 2022 08:33:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 31760C43141; Tue, 23 Aug 2022 08:33:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661243582; bh=PF8SufQ7tmxL2pVFNfXHYqLarhxmKG0VFpQoYTmqd98=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LwFNWLryWGdMFSqfbk0o50/kCG+mIhL7QOUAEQUcHQda/mvJZfhIIoUjj3yk1NV9F zyh3v4ie3yWdjbxOBDSDdbrW07Bg7dUCSDK2N/xG5wxg1xuMvQg2M65wpqTx8VjU+x WLgGSB7H38s/sGLchSoa3K3FrFtCNHqCWTirz1JA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Schspa Shi , Cornelia Huck , Alex Williamson , Sasha Levin Subject: [PATCH 5.19 322/365] vfio: Clear the caps->buf to NULL after free Date: Tue, 23 Aug 2022 10:03:43 +0200 Message-Id: <20220823080131.650582945@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220823080118.128342613@linuxfoundation.org> References: <20220823080118.128342613@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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 18fc0916587e..277cd1152dd8 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -1814,6 +1814,7 @@ struct vfio_info_cap_header *vfio_info_cap_add(struct= vfio_info_cap *caps, buf =3D krealloc(caps->buf, caps->size + size, GFP_KERNEL); if (!buf) { kfree(caps->buf); + caps->buf =3D NULL; caps->size =3D 0; return ERR_PTR(-ENOMEM); } --=20 2.35.1