From patchwork Wed Oct 9 15:53:15 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dafna Hirschfeld X-Patchwork-Id: 11181497 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CBA8913BD for ; Wed, 9 Oct 2019 15:53:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A86CA2190F for ; Wed, 9 Oct 2019 15:53:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731158AbfJIPxp (ORCPT ); Wed, 9 Oct 2019 11:53:45 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:34976 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729883AbfJIPxp (ORCPT ); Wed, 9 Oct 2019 11:53:45 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: dafna) with ESMTPSA id E2A80290475 From: Dafna Hirschfeld To: linux-media@vger.kernel.org Cc: dafna.hirschfeld@collabora.com, helen.koike@collabora.com, ezequiel@collabora.com, andre.almeida@collabora.com, skhan@linuxfoundation.org, hverkuil@xs4all.nl, kernel@collabora.com, dafna3@gmail.com Subject: [PATCH v3 2/2] media: vimc: upon streaming, check that the pipeline starts with a source entity Date: Wed, 9 Oct 2019 17:53:15 +0200 Message-Id: <20191009155315.14280-3-dafna.hirschfeld@collabora.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191009155315.14280-1-dafna.hirschfeld@collabora.com> References: <20191009155315.14280-1-dafna.hirschfeld@collabora.com> MIME-Version: 1.0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Userspace can disable links and create pipelines that do not start with a source entity. Trying to stream from such a pipeline should fail with -EPIPE currently this is not handled and cause kernel crash. Reproducing the crash: media-ctl -d0 -l "5:1->21:0[0]" -v v4l2-ctl -z platform:vimc -d "RGB/YUV Capture" -v width=1920,height=1440 v4l2-ctl --stream-mmap --stream-count=100 -d /dev/video2 Panic message: [ 39.078841][ T248] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 39.079338][ T248] #PF: supervisor read access in kernel mode [ 39.079704][ T248] #PF: error_code(0x0000) - not-present page [ 39.080071][ T248] PGD 0 P4D 0 [ 39.080279][ T248] Oops: 0000 [#1] SMP PTI [ 39.080546][ T248] CPU: 0 PID: 248 Comm: vimc-streamer t Not tainted 5.4.0-rc1+ #17 [ 39.081030][ T248] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014 [ 39.081779][ T248] RIP: 0010:vimc_sca_process_frame+0xdb/0x210 [vimc] [ 39.082191][ T248] Code: 44 8d 0c 28 8b 93 a4 01 00 00 48 8b 8b 98 01 00 00 85 d2 74 40 48 8b 74 24 10 8d 7a ff 4c 01 c9 31 d2 4c 01 fe eb 03 4c 89 c2 <44> 0f b6 04 16 44 88 04 11 4c 8d 42 01 48 39 fa 75 eb 8b 93 a4 01 [ 39.083436][ T248] RSP: 0018:ffffb15a005abe90 EFLAGS: 00010246 [ 39.083808][ T248] RAX: 0000000000000000 RBX: ffffa3fdc46d2e00 RCX: ffffb15a02579000 [ 39.084298][ T248] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002 [ 39.084792][ T248] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 39.085280][ T248] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 [ 39.085770][ T248] R13: ffffa3fdc46d2ee0 R14: 0000000000000000 R15: 0000000000000000 [ 39.086258][ T248] FS: 0000000000000000(0000) GS:ffffa3fdc7800000(0000) knlGS:0000000000000000 [ 39.086806][ T248] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 39.087217][ T248] CR2: 0000000000000000 CR3: 0000000003c92005 CR4: 0000000000360ef0 [ 39.087706][ T248] Call Trace: [ 39.087909][ T248] ? vimc_streamer_pipeline_terminate+0x90/0x90 [vimc] [ 39.088318][ T248] vimc_streamer_thread+0x7c/0xe0 [vimc] [ 39.088663][ T248] kthread+0x10d/0x130 [ 39.088919][ T248] ? kthread_park+0x80/0x80 [ 39.089205][ T248] ret_from_fork+0x35/0x40 [ 39.089475][ T248] Modules linked in: vimc videobuf2_vmalloc videobuf2_memops v4l2_tpg videobuf2_v4l2 videobuf2_common videodev mc [ 39.090208][ T248] CR2: 0000000000000000 [ 39.090463][ T248] ---[ end trace 697650fefbf78bee ]--- [ 39.090796][ T248] RIP: 0010:vimc_sca_process_frame+0xdb/0x210 [vimc] [ 39.091209][ T248] Code: 44 8d 0c 28 8b 93 a4 01 00 00 48 8b 8b 98 01 00 00 85 d2 74 40 48 8b 74 24 10 8d 7a ff 4c 01 c9 31 d2 4c 01 fe eb 03 4c 89 c2 <44> 0f b6 04 16 44 88 04 11 4c 8d 42 01 48 39 fa 75 eb 8b 93 a4 01 [ 39.092417][ T248] RSP: 0018:ffffb15a005abe90 EFLAGS: 00010246 [ 39.092789][ T248] RAX: 0000000000000000 RBX: ffffa3fdc46d2e00 RCX: ffffb15a02579000 [ 39.093278][ T248] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002 [ 39.093766][ T248] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 39.094254][ T248] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 [ 39.094742][ T248] R13: ffffa3fdc46d2ee0 R14: 0000000000000000 R15: 0000000000000000 [ 39.095309][ T248] FS: 0000000000000000(0000) GS:ffffa3fdc7800000(0000) knlGS:0000000000000000 [ 39.095974][ T248] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 39.096372][ T248] CR2: 0000000000000000 CR3: 0000000003c92005 CR4: 0000000000360ef0 Signed-off-by: Dafna Hirschfeld --- drivers/media/platform/vimc/vimc-common.c | 10 ++++++++ drivers/media/platform/vimc/vimc-common.h | 5 ++++ drivers/media/platform/vimc/vimc-streamer.c | 27 ++++++++++++--------- 3 files changed, 31 insertions(+), 11 deletions(-) diff --git a/drivers/media/platform/vimc/vimc-common.c b/drivers/media/platform/vimc/vimc-common.c index a3120f4f7a90..e8ad3199ffbf 100644 --- a/drivers/media/platform/vimc/vimc-common.c +++ b/drivers/media/platform/vimc/vimc-common.c @@ -164,6 +164,16 @@ static const struct vimc_pix_map vimc_pix_map_list[] = { }, }; +bool vimc_is_source(struct media_entity *ent) +{ + unsigned int i; + + for (i = 0; i < ent->num_pads; i++) + if (ent->pads[i].flags & MEDIA_PAD_FL_SINK) + return false; + return true; +} + const struct vimc_pix_map *vimc_pix_map_by_index(unsigned int i) { if (i >= ARRAY_SIZE(vimc_pix_map_list)) diff --git a/drivers/media/platform/vimc/vimc-common.h b/drivers/media/platform/vimc/vimc-common.h index 8349e3c68a49..112574bc3089 100644 --- a/drivers/media/platform/vimc/vimc-common.h +++ b/drivers/media/platform/vimc/vimc-common.h @@ -154,6 +154,11 @@ struct vimc_ent_config { void (*rm)(struct vimc_device *vimc, struct vimc_ent_device *ved); }; +/** + * vimc_is_source - returns true iff the entity has only source pads + */ +bool vimc_is_source(struct media_entity *ent); + /* prototypes for vimc_ent_config add and rm hooks */ struct vimc_ent_device *vimc_cap_add(struct vimc_device *vimc, const char *vcfg_name); diff --git a/drivers/media/platform/vimc/vimc-streamer.c b/drivers/media/platform/vimc/vimc-streamer.c index 37150c919fcb..680614851a14 100644 --- a/drivers/media/platform/vimc/vimc-streamer.c +++ b/drivers/media/platform/vimc/vimc-streamer.c @@ -82,14 +82,12 @@ static int vimc_streamer_pipeline_init(struct vimc_stream *stream, struct media_entity *entity; struct video_device *vdev; struct v4l2_subdev *sd; - int ret = 0; + int ret = -EINVAL; stream->pipe_size = 0; while (stream->pipe_size < VIMC_STREAMER_PIPELINE_MAX_SIZE) { - if (!ved) { - vimc_streamer_pipeline_terminate(stream); - return -EINVAL; - } + if (!ved) + break; stream->ved_pipeline[stream->pipe_size++] = ved; if (is_media_entity_v4l2_subdev(ved->ent)) { @@ -98,15 +96,23 @@ static int vimc_streamer_pipeline_init(struct vimc_stream *stream, if (ret && ret != -ENOIOCTLCMD) { dev_err(ved->dev, "subdev_call error %s\n", ved->ent->name); - vimc_streamer_pipeline_terminate(stream); - return ret; + break; } } entity = vimc_get_source_entity(ved->ent); - /* Check if the end of the pipeline was reached*/ - if (!entity) + /* Check if the end of the pipeline was reached */ + if (!entity) { + /* the first entity of the pipe should be source only */ + if (!vimc_is_source(ved->ent)) { + dev_err(ved->dev, + "first entity in the pipe '%s' is not a source\n", + ved->ent->name); + ret = -EPIPE; + break; + } return 0; + } /* Get the next device in the pipeline */ if (is_media_entity_v4l2_subdev(entity)) { @@ -119,9 +125,8 @@ static int vimc_streamer_pipeline_init(struct vimc_stream *stream, ved = video_get_drvdata(vdev); } } - vimc_streamer_pipeline_terminate(stream); - return -EINVAL; + return ret; } /**