Commit 6467cda1 authored by Yunfei Dong's avatar Yunfei Dong Committed by Hans Verkuil
Browse files

media: mediatek: vcodec: adding lock to protect decoder context list 



Add a lock for the ctx_list, to avoid accessing a NULL pointer
within the 'vpu_dec_ipi_handler' function when the ctx_list has
been deleted due to an unexpected behavior on the SCP IP block.

Hardware name: Google juniper sku16 board (DT)
pstate: 20400005 (nzCv daif +PAN -UAO -TCO BTYPE=--)
pc : vpu_dec_ipi_handler+0x58/0x1f8 [mtk_vcodec_dec]
lr : scp_ipi_handler+0xd0/0x194 [mtk_scp]
sp : ffffffc0131dbbd0
x29: ffffffc0131dbbd0 x28: 0000000000000000
x27: ffffff9bb277f348 x26: ffffff9bb242ad00
x25: ffffffd2d440d3b8 x24: ffffffd2a13ff1d4
x23: ffffff9bb7fe85a0 x22: ffffffc0133fbdb0
x21: 0000000000000010 x20: ffffff9b050ea328
x19: ffffffc0131dbc08 x18: 0000000000001000
x17: 0000000000000000 x16: ffffffd2d461c6e0
x15: 0000000000000242 x14: 000000000000018f
x13: 000000000000004d x12: 0000000000000000
x11: 0000000000000001 x10: fffffffffffffff0
x9 : ffffff9bb6e793a8 x8 : 0000000000000000
x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : fffffffffffffff0
x3 : 0000000000000020 x2 : ffffff9bb6e79080
x1 : 0000000000000010 x0 : ffffffc0131dbc08
Call trace:
vpu_dec_ipi_handler+0x58/0x1f8 [mtk_vcodec_dec (HASH:6c3f 2)]
scp_ipi_handler+0xd0/0x194 [mtk_scp (HASH:7046 3)]
mt8183_scp_irq_handler+0x44/0x88 [mtk_scp (HASH:7046 3)]
scp_irq_handler+0x48/0x90 [mtk_scp (HASH:7046 3)]
irq_thread_fn+0x38/0x94
irq_thread+0x100/0x1c0
kthread+0x140/0x1fc
ret_from_fork+0x10/0x30
Code: 54000088 f94ca50a eb14015f 54000060 (f9400108)
---[ end trace ace43ce36cbd5c93 ]---
Kernel panic - not syncing: Oops: Fatal exception
SMP: stopping secondary CPUs
Kernel Offset: 0x12c4000000 from 0xffffffc010000000
PHYS_OFFSET: 0xffffffe580000000
CPU features: 0x08240002,2188200c
Memory Limit: none

Fixes: 655b86e5 ("media: mediatek: vcodec: Fix possible invalid memory access for decoder")
Signed-off-by: default avatarYunfei Dong <yunfei.dong@mediatek.com>
Reviewed-by: default avatarNicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: default avatarAngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: default avatarSebastian Fricke <sebastian.fricke@collabora.com>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
parent 97c75ee5

drivers/media/platform/mediatek/vcodec/common/mtk_vcodec_fw_vpu.c

+2 −2
Original line number Diff line number Diff line
@@ -50,12 +50,12 @@ static void mtk_vcodec_vpu_reset_dec_handler(void *priv) 


	dev_err(&dev->plat_dev->dev, "Watchdog timeout!!");



	mutex_lock(&dev->dev_mutex);

	mutex_lock(&dev->dev_ctx_lock);

	list_for_each_entry(ctx, &dev->ctx_list, list) {

		ctx->state = MTK_STATE_ABORT;

		mtk_v4l2_vdec_dbg(0, ctx, "[%d] Change to state MTK_STATE_ABORT", ctx->id);

	}

	mutex_unlock(&dev->dev_mutex);

	mutex_unlock(&dev->dev_ctx_lock);

}



static void mtk_vcodec_vpu_reset_enc_handler(void *priv)

drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_drv.c

+5 −0
Original line number Diff line number Diff line
@@ -268,7 +268,9 @@ static int fops_vcodec_open(struct file *file) 


	ctx->dev->vdec_pdata->init_vdec_params(ctx);



	mutex_lock(&dev->dev_ctx_lock);

	list_add(&ctx->list, &dev->ctx_list);

	mutex_unlock(&dev->dev_ctx_lock);

	mtk_vcodec_dbgfs_create(ctx);



	mutex_unlock(&dev->dev_mutex);
@@ -311,7 +313,9 @@ static int fops_vcodec_release(struct file *file) 
	v4l2_ctrl_handler_free(&ctx->ctrl_hdl);



	mtk_vcodec_dbgfs_remove(dev, ctx->id);

	mutex_lock(&dev->dev_ctx_lock);

	list_del_init(&ctx->list);

	mutex_unlock(&dev->dev_ctx_lock);

	kfree(ctx);

	mutex_unlock(&dev->dev_mutex);

	return 0;
@@ -404,6 +408,7 @@ static int mtk_vcodec_probe(struct platform_device *pdev) 
	for (i = 0; i < MTK_VDEC_HW_MAX; i++)

		mutex_init(&dev->dec_mutex[i]);

	mutex_init(&dev->dev_mutex);

	mutex_init(&dev->dev_ctx_lock);

	spin_lock_init(&dev->irqlock);



	snprintf(dev->v4l2_dev.name, sizeof(dev->v4l2_dev.name), "%s",

drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_drv.h

+2 −0
Original line number Diff line number Diff line
@@ -241,6 +241,7 @@ struct mtk_vcodec_dec_ctx { 
 *

 * @dec_mutex: decoder hardware lock

 * @dev_mutex: video_device lock

 * @dev_ctx_lock: the lock of context list

 * @decode_workqueue: decode work queue

 *

 * @irqlock: protect data access by irq handler and work thread
@@ -282,6 +283,7 @@ struct mtk_vcodec_dec_dev { 
	/* decoder hardware mutex lock */

	struct mutex dec_mutex[MTK_VDEC_HW_MAX];

	struct mutex dev_mutex;

	struct mutex dev_ctx_lock;

	struct workqueue_struct *decode_workqueue;



	spinlock_t irqlock;

drivers/media/platform/mediatek/vcodec/decoder/vdec_vpu_if.c

+2 −0
Original line number Diff line number Diff line
@@ -77,12 +77,14 @@ static bool vpu_dec_check_ap_inst(struct mtk_vcodec_dec_dev *dec_dev, struct vde 
	struct mtk_vcodec_dec_ctx *ctx;

	int ret = false;



	mutex_lock(&dec_dev->dev_ctx_lock);

	list_for_each_entry(ctx, &dec_dev->ctx_list, list) {

		if (!IS_ERR_OR_NULL(ctx) && ctx->vpu_inst == vpu) {

			ret = true;

			break;

		}

	}

	mutex_unlock(&dec_dev->dev_ctx_lock);



	return ret;

}