In the Linux kernel, the following vulnerability has been resolved:
USB: gadget: Fix the memory leak in raw_gadget driver
Currently, increasing raw_dev->count happens before invoke the raw_queue_event(), if the raw_queue_event() return error, invoke raw_release() will not trigger the dev_free() to be called.
[ 268.905865][ T5067] raw-gadget.0 gadget.0: failed to queue event [ 268.912053][ T5067] udc dummy_udc.0: failed to start USB Raw Gadget: -12 [ 268.918885][ T5067] raw-gadget.0: probe of gadget.0 failed with error -12 [ 268.925956][ T5067] UDC core: USB Raw Gadget: couldnt find an available UDC or its busy [ 268.934657][ T5067] misc raw-gadget: fail, usb_gadget_register_driver returned -16
BUG: memory leak
[] kmalloc_trace+0x24/0x90 mm/slab_common.c:1076 [] kmalloc include/linux/slab.h:582 [inline] [] kzalloc include/linux/slab.h:703 [inline] [] dev_new drivers/usb/gadget/legacy/raw_gadget.c:191 [inline] [] raw_open+0x45/0x110 drivers/usb/gadget/legacy/raw_gadget.c:385 [] misc_open+0x1a9/0x1f0 drivers/char/misc.c:165
[] kmalloc_trace+0x24/0x90 mm/slab_common.c:1076 [] kmalloc include/linux/slab.h:582 [inline] [] raw_ioctl_init+0xdf/0x410 drivers/usb/gadget/legacy/raw_gadget.c:460 [] raw_ioctl+0x5f9/0x1120 drivers/usb/gadget/legacy/raw_gadget.c:1250 [] vfs_ioctl fs/ioctl.c:51 [inline]
[] kmalloc_trace+0x24/0x90 mm/slab_common.c:1076 [] kmalloc include/linux/slab.h:582 [inline] [] kzalloc include/linux/slab.h:703 [inline] [] dummy_alloc_request+0x5a/0xe0 drivers/usb/gadget/udc/dummy_hcd.c:665 [] usb_ep_alloc_request+0x22/0xd0 drivers/usb/gadget/udc/core.c:196 [] gadget_bind+0x6d/0x370 drivers/usb/gadget/legacy/raw_gadget.c:292
This commit therefore invoke kref_get() under the condition that raw_queue_event() return success.