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 51A55C433FE for ; Wed, 19 Oct 2022 10:36:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231178AbiJSKgz (ORCPT ); Wed, 19 Oct 2022 06:36:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230120AbiJSKgc (ORCPT ); Wed, 19 Oct 2022 06:36:32 -0400 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD97DFF8C9; Wed, 19 Oct 2022 03:15:23 -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 sin.source.kernel.org (Postfix) with ESMTPS id 9C9ECCE21CB; Wed, 19 Oct 2022 09:13:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9A61DC433C1; Wed, 19 Oct 2022 09:13:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666170803; bh=u/bw0MPMS/QV/9IoNFCmnYBw0YZ8rHNhw+FhHjhGJJE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g8+DaP1h1twAwayRjjQbUPT7pZxig55sFkcmNDrmHgY53rOy1kKISkc6KcDlwYgHE mh14elmOHr99xYWfUyf4hS5gumchndc2oeXqX7dq2+acHvfQ0zczi5YkuhkP/dzabC QpPTeHZ/KaP+e10gU9cTs4/b4Jh/rDV4EQ3Ebj5A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Zheyu Ma , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 6.0 793/862] media: cx88: Fix a null-ptr-deref bug in buffer_prepare() Date: Wed, 19 Oct 2022 10:34:40 +0200 Message-Id: <20221019083324.959657054@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221019083249.951566199@linuxfoundation.org> References: <20221019083249.951566199@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Zheyu Ma [ Upstream commit 2b064d91440b33fba5b452f2d1b31f13ae911d71 ] When the driver calls cx88_risc_buffer() to prepare the buffer, the function call may fail, resulting in a empty buffer and null-ptr-deref later in buffer_queue(). The following log can reveal it: [ 41.822762] general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI [ 41.824488] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] [ 41.828027] RIP: 0010:buffer_queue+0xc2/0x500 [ 41.836311] Call Trace: [ 41.836945] __enqueue_in_driver+0x141/0x360 [ 41.837262] vb2_start_streaming+0x62/0x4a0 [ 41.838216] vb2_core_streamon+0x1da/0x2c0 [ 41.838516] __vb2_init_fileio+0x981/0xbc0 [ 41.839141] __vb2_perform_fileio+0xbf9/0x1120 [ 41.840072] vb2_fop_read+0x20e/0x400 [ 41.840346] v4l2_read+0x215/0x290 [ 41.840603] vfs_read+0x162/0x4c0 Fix this by checking the return value of cx88_risc_buffer() [hverkuil: fix coding style issues] Signed-off-by: Zheyu Ma Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/pci/cx88/cx88-vbi.c | 9 +++--- drivers/media/pci/cx88/cx88-video.c | 43 +++++++++++++++-------------- 2 files changed, 26 insertions(+), 26 deletions(-) diff --git a/drivers/media/pci/cx88/cx88-vbi.c b/drivers/media/pci/cx88/cx88-vbi.c index a075788c64d4..469aeaa725ad 100644 --- a/drivers/media/pci/cx88/cx88-vbi.c +++ b/drivers/media/pci/cx88/cx88-vbi.c @@ -144,11 +144,10 @@ static int buffer_prepare(struct vb2_buffer *vb) return -EINVAL; vb2_set_plane_payload(vb, 0, size); - cx88_risc_buffer(dev->pci, &buf->risc, sgt->sgl, - 0, VBI_LINE_LENGTH * lines, - VBI_LINE_LENGTH, 0, - lines); - return 0; + return cx88_risc_buffer(dev->pci, &buf->risc, sgt->sgl, + 0, VBI_LINE_LENGTH * lines, + VBI_LINE_LENGTH, 0, + lines); } static void buffer_finish(struct vb2_buffer *vb) diff --git a/drivers/media/pci/cx88/cx88-video.c b/drivers/media/pci/cx88/cx88-video.c index d3729be89252..b509c2a03852 100644 --- a/drivers/media/pci/cx88/cx88-video.c +++ b/drivers/media/pci/cx88/cx88-video.c @@ -431,6 +431,7 @@ static int queue_setup(struct vb2_queue *q, static int buffer_prepare(struct vb2_buffer *vb) { + int ret; struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb); struct cx8800_dev *dev = vb->vb2_queue->drv_priv; struct cx88_core *core = dev->core; @@ -445,35 +446,35 @@ static int buffer_prepare(struct vb2_buffer *vb) switch (core->field) { case V4L2_FIELD_TOP: - cx88_risc_buffer(dev->pci, &buf->risc, - sgt->sgl, 0, UNSET, - buf->bpl, 0, core->height); + ret = cx88_risc_buffer(dev->pci, &buf->risc, + sgt->sgl, 0, UNSET, + buf->bpl, 0, core->height); break; case V4L2_FIELD_BOTTOM: - cx88_risc_buffer(dev->pci, &buf->risc, - sgt->sgl, UNSET, 0, - buf->bpl, 0, core->height); + ret = cx88_risc_buffer(dev->pci, &buf->risc, + sgt->sgl, UNSET, 0, + buf->bpl, 0, core->height); break; case V4L2_FIELD_SEQ_TB: - cx88_risc_buffer(dev->pci, &buf->risc, - sgt->sgl, - 0, buf->bpl * (core->height >> 1), - buf->bpl, 0, - core->height >> 1); + ret = cx88_risc_buffer(dev->pci, &buf->risc, + sgt->sgl, + 0, buf->bpl * (core->height >> 1), + buf->bpl, 0, + core->height >> 1); break; case V4L2_FIELD_SEQ_BT: - cx88_risc_buffer(dev->pci, &buf->risc, - sgt->sgl, - buf->bpl * (core->height >> 1), 0, - buf->bpl, 0, - core->height >> 1); + ret = cx88_risc_buffer(dev->pci, &buf->risc, + sgt->sgl, + buf->bpl * (core->height >> 1), 0, + buf->bpl, 0, + core->height >> 1); break; case V4L2_FIELD_INTERLACED: default: - cx88_risc_buffer(dev->pci, &buf->risc, - sgt->sgl, 0, buf->bpl, - buf->bpl, buf->bpl, - core->height >> 1); + ret = cx88_risc_buffer(dev->pci, &buf->risc, + sgt->sgl, 0, buf->bpl, + buf->bpl, buf->bpl, + core->height >> 1); break; } dprintk(2, @@ -481,7 +482,7 @@ static int buffer_prepare(struct vb2_buffer *vb) buf, buf->vb.vb2_buf.index, __func__, core->width, core->height, dev->fmt->depth, dev->fmt->fourcc, (unsigned long)buf->risc.dma); - return 0; + return ret; } static void buffer_finish(struct vb2_buffer *vb) -- 2.35.1