em28xx_audio_urb_init() divides by the audio endpoint's wMaxPacketSize without checking it, so a USB device that declares a zero-sized audio endpoint divides by zero at probe time. Reject a zero-sized audio endpoint like a missing one; the caller already unwinds on a negative return. Oops: divide error: 0000 [#1] SMP NOPTI Workqueue: usb_hub_wq hub_event RIP: 0010:em28xx_audio_init (drivers/media/usb/em28xx/em28xx-audio.c:718) Call Trace: em28xx_init_extension (drivers/media/usb/em28xx/em28xx-core.c:1248) em28xx_init_dev.isra.0 (drivers/media/usb/em28xx/em28xx-cards.c:3887) em28xx_usb_probe (drivers/media/usb/em28xx/em28xx-cards.c:4258) usb_probe_interface (drivers/usb/core/driver.c:396) ... usb_set_configuration (drivers/usb/core/message.c:2268) usb_generic_driver_probe (drivers/usb/core/generic.c:250) usb_probe_device (drivers/usb/core/driver.c:291) ... usb_new_device (drivers/usb/core/hub.c:2703) hub_event (drivers/usb/core/hub.c:5961) process_one_work (kernel/workqueue.c:3322) worker_thread (kernel/workqueue.c:3486) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:158) ret_from_fork_asm (arch/x86/entry/entry_64.S:245) Kernel panic - not syncing: Fatal exception Fixes: 1b3fd2d34266 ("[media] em28xx-audio: don't hardcode audio URB calculus") Cc: stable@vger.kernel.org Reported-by: co+9782320f78c23f40@bugs.sh Closes: https://lore.kernel.org/all/51lCz4R7QyTUKbh4mhXNaNzX0evpk0siOzbh%40bugs.sh/ Assisted-by: Claude:claude-opus-5 Signed-off-by: Xiang Mei --- drivers/media/usb/em28xx/em28xx-audio.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/media/usb/em28xx/em28xx-audio.c b/drivers/media/usb/em28xx/em28xx-audio.c index ccff6be5599e..7f0c5826ce5e 100644 --- a/drivers/media/usb/em28xx/em28xx-audio.c +++ b/drivers/media/usb/em28xx/em28xx-audio.c @@ -693,6 +693,13 @@ static int em28xx_audio_urb_init(struct em28xx *dev) } ep_size = em28xx_audio_ep_packet_size(udev, ep); + if (ep_size == 0) { + dev_err(&dev->intf->dev, + "Audio endpoint 0x%02x has a zero packet size\n", + EM28XX_EP_AUDIO); + return -ENODEV; + } + interval = 1 << (ep->bInterval - 1); dev_info(&dev->intf->dev, -- 2.43.0