Commits
Chao Bi committed 97839ca4b06
usb: gadget: ffs: race between ffs_epfile_io() and ffs_func_eps_disable() ffs_epfile_io() is called from userspace, while ffs_func_eps_disable() might be called from USB disconnect interrupt, the two functions would run in parallel but they are not well protected, that epfile->ep would be removed by ffs_func_eps_disable() during ffs_epfile_io() is referring this pointer, then it leads to kernel PANIC. The scenario is as below: Thread 1 Thread 2 | | SyS_read dwc3_gadget_disconnect_interrupt | | ffs_epfile_read reset_config | | ffs_epfile_io ffs_func_eps_disable | | ----- usb_ep_disable(): epfile->ep->ep->desc = NULL | | usb_ep_align_maybe(): ----- it refers ep->desc->wMaxPacketSize ----- Signed-off-by: Chao Bi <chao.bi@intel.com> Signed-off-by: Felipe Balbi <balbi@ti.com>