Commit 80264809 authored by Benoit Parrot's avatar Benoit Parrot Committed by Mauro Carvalho Chehab
Browse files

media: ti-vpe: cal: fix a kernel oops when unloading module 



After the switch to use v4l2_async_notifier_add_subdev() and
v4l2_async_notifier_cleanup(), unloading the ti_cal module would cause a
kernel oops.

This was root cause to the fact that v4l2_async_notifier_cleanup() tries
to kfree the asd pointer passed into v4l2_async_notifier_add_subdev().

In our case the asd reference was from a statically allocated struct.
So in effect v4l2_async_notifier_cleanup() was trying to free a pointer
that was not kalloc.

So here we switch to using a kzalloc struct instead of a static one.
To achieve this we re-order some of the calls to prevent asd allocation
from leaking.

Fixes: d079f94c ("media: platform: Switch to v4l2_async_notifier_add_subdev")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarBenoit Parrot <bparrot@ti.com>
Reviewed-by: default avatarTomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent e6599adf

drivers/media/platform/ti-vpe/cal.c

+8 −5
Original line number Diff line number Diff line
@@ -372,8 +372,6 @@ struct cal_ctx { 
	struct v4l2_subdev	*sensor;

	struct v4l2_fwnode_endpoint	endpoint;



	struct v4l2_async_subdev asd;



	struct v4l2_fh		fh;

	struct cal_dev		*dev;

	struct cc_data		*cc;
@@ -2032,7 +2030,6 @@ static int of_cal_create_instance(struct cal_ctx *ctx, int inst) 


	parent = pdev->dev.of_node;



	asd = &ctx->asd;

	endpoint = &ctx->endpoint;



	ep_node = NULL;
@@ -2079,8 +2076,6 @@ static int of_cal_create_instance(struct cal_ctx *ctx, int inst) 
		ctx_dbg(3, ctx, "can't get remote parent\n");

		goto cleanup_exit;

	}

	asd->match_type = V4L2_ASYNC_MATCH_FWNODE;

	asd->match.fwnode = of_fwnode_handle(sensor_node);



	v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep_node), endpoint);
@@ -2110,9 +2105,17 @@ static int of_cal_create_instance(struct cal_ctx *ctx, int inst) 


	v4l2_async_notifier_init(&ctx->notifier);



	asd = kzalloc(sizeof(*asd), GFP_KERNEL);

	if (!asd)

		goto cleanup_exit;



	asd->match_type = V4L2_ASYNC_MATCH_FWNODE;

	asd->match.fwnode = of_fwnode_handle(sensor_node);



	ret = v4l2_async_notifier_add_subdev(&ctx->notifier, asd);

	if (ret) {

		ctx_err(ctx, "Error adding asd\n");

		kfree(asd);

		goto cleanup_exit;

	}