Hi Yuan,
Thank you for the patch.
On Thu, Dec 08, 2022 at 08:06:25AM +0000, Yuan Can wrote:
> A memory leak was reported when testing ov772x with bpf mock device:
>
> AssertionError: unreferenced object 0xffff888109afa7a8 (size 8):
> comm "python3", pid 279, jiffies 4294805921 (age 20.681s)
> hex dump (first 8 bytes):
> 80 22 88 15 81 88 ff ff ."......
> backtrace:
> [<000000009990b438>] __kmalloc_node+0x44/0x1b0
> [<000000009e32f7d7>] kvmalloc_node+0x34/0x180
> [<00000000faf48134>] v4l2_ctrl_handler_init_class+0x11d/0x180 [videodev]
> [<00000000da376937>] ov772x_probe+0x1c3/0x68c [ov772x]
> [<000000003f0d225e>] i2c_device_probe+0x28d/0x680
> [<00000000e0b6db89>] really_probe+0x17c/0x3f0
> [<000000001b19fcee>] __driver_probe_device+0xe3/0x170
> [<0000000048370519>] driver_probe_device+0x49/0x120
> [<000000005ead07a0>] __device_attach_driver+0xf7/0x150
> [<0000000043f452b8>] bus_for_each_drv+0x114/0x180
> [<00000000358e5596>] __device_attach+0x1e5/0x2d0
> [<0000000043f83c5d>] bus_probe_device+0x126/0x140
> [<00000000ee0f3046>] device_add+0x810/0x1130
> [<00000000e0278184>] i2c_new_client_device+0x359/0x4f0
> [<0000000070baf34f>] of_i2c_register_device+0xf1/0x110
> [<00000000a9f2159d>] of_i2c_notify+0x100/0x160
> unreferenced object 0xffff888119825c00 (size 256):
> comm "python3", pid 279, jiffies 4294805921 (age 20.681s)
> hex dump (first 32 bytes):
> 00 b4 a5 17 81 88 ff ff 00 5e 82 19 81 88 ff ff .........^......
> 10 5c 82 19 81 88 ff ff 10 5c 82 19 81 88 ff ff .\.......\......
> backtrace:
> [<000000009990b438>] __kmalloc_node+0x44/0x1b0
> [<000000009e32f7d7>] kvmalloc_node+0x34/0x180
> [<0000000073d88e0b>] v4l2_ctrl_new.cold+0x19b/0x86f [videodev]
> [<00000000b1f576fb>] v4l2_ctrl_new_std+0x16f/0x210 [videodev]
> [<00000000caf7ac99>] ov772x_probe+0x1fa/0x68c [ov772x]
> [<000000003f0d225e>] i2c_device_probe+0x28d/0x680
> [<00000000e0b6db89>] really_probe+0x17c/0x3f0
> [<000000001b19fcee>] __driver_probe_device+0xe3/0x170
> [<0000000048370519>] driver_probe_device+0x49/0x120
> [<000000005ead07a0>] __device_attach_driver+0xf7/0x150
> [<0000000043f452b8>] bus_for_each_drv+0x114/0x180
> [<00000000358e5596>] __device_attach+0x1e5/0x2d0
> [<0000000043f83c5d>] bus_probe_device+0x126/0x140
> [<00000000ee0f3046>] device_add+0x810/0x1130
> [<00000000e0278184>] i2c_new_client_device+0x359/0x4f0
> [<0000000070baf34f>] of_i2c_register_device+0xf1/0x110
>
> The reason is that if priv->hdl.error is set, ov772x_probe() jumps to the
> error_mutex_destroy without doing v4l2_ctrl_handler_free(), and all
> resources allocated in v4l2_ctrl_handler_init() and v4l2_ctrl_new_std()
> are leaked.
>
> Fixes: 1112babde214 ("media: i2c: Copy ov772x soc_camera sensor driver")
> Signed-off-by: Yuan Can <yuancan@xxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> ---
> drivers/media/i2c/ov772x.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/media/i2c/ov772x.c b/drivers/media/i2c/ov772x.c
> index 4189e3fc3d53..a238e63425f8 100644
> --- a/drivers/media/i2c/ov772x.c
> +++ b/drivers/media/i2c/ov772x.c
> @@ -1462,7 +1462,7 @@ static int ov772x_probe(struct i2c_client *client)
> priv->subdev.ctrl_handler = &priv->hdl;
> if (priv->hdl.error) {
> ret = priv->hdl.error;
> - goto error_mutex_destroy;
> + goto error_ctrl_free;
> }
>
> priv->clk = clk_get(&client->dev, NULL);
> @@ -1515,7 +1515,6 @@ static int ov772x_probe(struct i2c_client *client)
> clk_put(priv->clk);
> error_ctrl_free:
> v4l2_ctrl_handler_free(&priv->hdl);
> -error_mutex_destroy:
> mutex_destroy(&priv->lock);
>
> return ret;
--
Regards,
Laurent Pinchart
