[PATCH] media: cpia2: fix memory leak in cpia2_usb_probe

From: Pavel Skripkin
Date: Wed Apr 21 2021 - 15:43:56 EST


syzbot reported leak in cpia2 usb driver. The problem was
in invalid error handling.

v4l2_device_register() is called in cpia2_init_camera_struct(), but
all error cases after cpia2_init_camera_struct() did not call the
v4l2_device_unregister()

Reported-by: syzbot+d1e69c888f0d3866ead4@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx>
---
drivers/media/usb/cpia2/cpia2.h | 1 +
drivers/media/usb/cpia2/cpia2_core.c | 12 ++++++++++++
drivers/media/usb/cpia2/cpia2_usb.c | 13 +++++++------
3 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/drivers/media/usb/cpia2/cpia2.h b/drivers/media/usb/cpia2/cpia2.h
index 50835f5f7512..57b7f1ea68da 100644
--- a/drivers/media/usb/cpia2/cpia2.h
+++ b/drivers/media/usb/cpia2/cpia2.h
@@ -429,6 +429,7 @@ int cpia2_send_command(struct camera_data *cam, struct cpia2_command *cmd);
int cpia2_do_command(struct camera_data *cam,
unsigned int command,
unsigned char direction, unsigned char param);
+void cpia2_deinit_camera_struct(struct camera_data *cam, struct usb_interface *intf);
struct camera_data *cpia2_init_camera_struct(struct usb_interface *intf);
int cpia2_init_camera(struct camera_data *cam);
int cpia2_allocate_buffers(struct camera_data *cam);
diff --git a/drivers/media/usb/cpia2/cpia2_core.c b/drivers/media/usb/cpia2/cpia2_core.c
index e747548ab286..b5a2d06fb356 100644
--- a/drivers/media/usb/cpia2/cpia2_core.c
+++ b/drivers/media/usb/cpia2/cpia2_core.c
@@ -2163,6 +2163,18 @@ static void reset_camera_struct(struct camera_data *cam)
cam->height = cam->params.roi.height;
}

+/******************************************************************************
+ *
+ * cpia2_init_camera_struct
+ *
+ * Deinitialize camera struct
+ *****************************************************************************/
+void cpia2_deinit_camera_struct(struct camera_data *cam, struct usb_interface *intf)
+{
+ v4l2_device_unregister(&cam->v4l2_dev);
+ kfree(cam);
+}
+
/******************************************************************************
*
* cpia2_init_camera_struct
diff --git a/drivers/media/usb/cpia2/cpia2_usb.c b/drivers/media/usb/cpia2/cpia2_usb.c
index 3ab80a7b4498..76aac06f9fb8 100644
--- a/drivers/media/usb/cpia2/cpia2_usb.c
+++ b/drivers/media/usb/cpia2/cpia2_usb.c
@@ -844,15 +844,13 @@ static int cpia2_usb_probe(struct usb_interface *intf,
ret = set_alternate(cam, USBIF_CMDONLY);
if (ret < 0) {
ERR("%s: usb_set_interface error (ret = %d)\n", __func__, ret);
- kfree(cam);
- return ret;
+ goto alt_err;
}


if((ret = cpia2_init_camera(cam)) < 0) {
ERR("%s: failed to initialize cpia2 camera (ret = %d)\n", __func__, ret);
- kfree(cam);
- return ret;
+ goto alt_err;
}
LOG(" CPiA Version: %d.%02d (%d.%d)\n",
cam->params.version.firmware_revision_hi,
@@ -872,11 +870,14 @@ static int cpia2_usb_probe(struct usb_interface *intf,
ret = cpia2_register_camera(cam);
if (ret < 0) {
ERR("%s: Failed to register cpia2 camera (ret = %d)\n", __func__, ret);
- kfree(cam);
- return ret;
+ goto alt_err;
}

return 0;
+
+alt_err:
+ cpia2_deinit_camera_struct(cam, intf);
+ return ret;
}

/******************************************************************************
--
2.31.1