[PATCH 5.4 058/320] media: mtk-vcodec: call v4l2_m2m_ctx_release first when file is released

Greg Kroah-Hartman
2022-01-24T19:32:01Z

From: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>

[ Upstream commit 9f89c881bffbdffe4060ffaef3489a2830a6dd9c ]

The func v4l2_m2m_ctx_release waits for currently running jobs
to finish and then stop streaming both queues and frees the buffers.
All this should be done before the call to mtk_vcodec_enc_release
which frees the encoder handler. This fixes null-pointer dereference bug:

[ 638.028076] Mem abort info:
[ 638.030932] ESR = 0x96000004
[ 638.033978] EC = 0x25: DABT (current EL), IL = 32 bits
[ 638.039293] SET = 0, FnV = 0
[ 638.042338] EA = 0, S1PTW = 0
[ 638.045474] FSC = 0x04: level 0 translation fault
[ 638.050349] Data abort info:
[ 638.053224] ISV = 0, ISS = 0x00000004
[ 638.057055] CM = 0, WnR = 0
[ 638.060018] user pgtable: 4k pages, 48-bit VAs, pgdp=000000012b6db000
[ 638.066485] [00000000000001a0] pgd=0000000000000000, p4d=0000000000000000
[ 638.073277] Internal error: Oops: 96000004 [#1] SMP
[ 638.078145] Modules linked in: rfkill mtk_vcodec_dec mtk_vcodec_enc uvcvideo mtk_mdp mtk_vcodec_common videobuf2_dma_contig v4l2_h264 cdc_ether v4l2_mem2mem videobuf2_vmalloc usbnet videobuf2_memops videobuf2_v4l2 r8152 videobuf2_common videodev cros_ec_sensors cros_ec_sensors_core industrialio_triggered_buffer kfifo_buf elan_i2c elants_i2c sbs_battery mc cros_usbpd_charger cros_ec_chardev cros_usbpd_logger crct10dif_ce mtk_vpu fuse ip_tables x_tables ipv6
[ 638.118583] CPU: 0 PID: 212 Comm: kworker/u8:5 Not tainted 5.15.0-06427-g58a1d4dcfc74-dirty #109
[ 638.127357] Hardware name: Google Elm (DT)
[ 638.131444] Workqueue: mtk-vcodec-enc mtk_venc_worker [mtk_vcodec_enc]
[ 638.137974] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 638.144925] pc : vp8_enc_encode+0x34/0x2b0 [mtk_vcodec_enc]
[ 638.150493] lr : venc_if_encode+0xac/0x1b0 [mtk_vcodec_enc]
[ 638.156060] sp : ffff8000124d3c40
[ 638.159364] x29: ffff8000124d3c40 x28: 0000000000000000 x27: 0000000000000000
[ 638.166493] x26: 0000000000000000 x25: ffff0000e7f252d0 x24: ffff8000124d3d58
[ 638.173621] x23: ffff8000124d3d58 x22: ffff8000124d3d60 x21: 0000000000000001
[ 638.180750] x20: ffff80001137e000 x19: 0000000000000000 x18: 0000000000000001
[ 638.187878] x17: 000000040044ffff x16: 00400032b5503510 x15: 0000000000000000
[ 638.195006] x14: ffff8000118536c0 x13: ffff8000ee1da000 x12: 0000000030d4d91d
[ 638.202134] x11: 0000000000000000 x10: 0000000000000980 x9 : ffff8000124d3b20
[ 638.209262] x8 : ffff0000c18d4ea0 x7 : ffff0000c18d44c0 x6 : ffff0000c18d44c0
[ 638.216391] x5 : ffff80000904a3b0 x4 : ffff8000124d3d58 x3 : ffff8000124d3d60
[ 638.223519] x2 : ffff8000124d3d78 x1 : 0000000000000001 x0 : ffff80001137efb8
[ 638.230648] Call trace:
[ 638.233084] vp8_enc_encode+0x34/0x2b0 [mtk_vcodec_enc]
[ 638.238304] venc_if_encode+0xac/0x1b0 [mtk_vcodec_enc]
[ 638.243525] mtk_venc_worker+0x110/0x250 [mtk_vcodec_enc]
[ 638.248918] process_one_work+0x1f8/0x498
[ 638.252923] worker_thread+0x140/0x538
[ 638.256664] kthread+0x148/0x158
[ 638.259884] ret_from_fork+0x10/0x20
[ 638.263455] Code: f90023f9 2a0103f5 aa0303f6 aa0403f8 (f940d277)
[ 638.269538] ---[ end trace e374fc10f8e181f5 ]---

[gst-master] root@debian:~/gst-build# [ 638.019193] Unable to handle kernel NULL pointer dereference at virtual address 00000000000001a0
Fixes: 4e855a6efa547 ("[media] vcodec: mediatek: Add Mediatek V4L2 Video Encoder Driver")
Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/platform/mtk-vcodec/mtk_vcodec_enc_drv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/platform/mtk-vcodec/mtk_vcodec_enc_drv.c b/drivers/media/platform/mtk-vcodec/mtk_vcodec_enc_drv.c
index 1d82aa2b6017c..dea0ee2cb7245 100644
--- a/drivers/media/platform/mtk-vcodec/mtk_vcodec_enc_drv.c
+++ b/drivers/media/platform/mtk-vcodec/mtk_vcodec_enc_drv.c
@@ -209,11 +209,11 @@ static int fops_vcodec_release(struct file *file)
mtk_v4l2_debug(1, "[%d] encoder", ctx->id);
mutex_lock(&dev->dev_mutex);

+ v4l2_m2m_ctx_release(ctx->m2m_ctx);
mtk_vcodec_enc_release(ctx);
v4l2_fh_del(&ctx->fh);
v4l2_fh_exit(&ctx->fh);
v4l2_ctrl_handler_free(&ctx->ctrl_hdl);
- v4l2_m2m_ctx_release(ctx->m2m_ctx);

list_del_init(&ctx->list);
kfree(ctx);
--
2.34.1