[PATCH v2 0/4] USB: serial: fix port tear down use-after-free

From: Johan Hovold

Date: Fri Aug 21 2026 - 11:53:05 EST


When addressing a port probe ordering issue in digi_acceleport recently
I realised that we have a corresponding general problem during
disconnect, but I didn't have time to address it straight away.

Now syzbot has managed to trigger one of its symptoms and people have
already started submitting incomplete band-aids so here is a proper
fix.

When testing the fix I also noticed that we have an ordering issue when
deregistering drivers that can result in similar use-after-free.

Johan


Changes in v2:
- fix dynamic id driver deregistration race (new)
- remove "new_id" attributes before deregistering USB driver
- use iterator for driver deregistration (new)


Johan Hovold (4):
USB: serial: fix port tear down use-after-free
USB: serial: fix dynamic id driver deregistration race
USB: serial: fix driver deregistration order
USB: serial: use iterator for driver deregistration

drivers/usb/serial/bus.c | 6 +++++-
drivers/usb/serial/usb-serial.c | 32 ++++++++++++++++++++++++++------
include/linux/usb/serial.h | 1 +
3 files changed, 32 insertions(+), 7 deletions(-)

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2.54.0