linux

iv/linux

History

Maxime Bizon a398d5eac6 usb-storage: fix deadlock when a scsi command timeouts more than once

With faulty usb-storage devices, read/write can timeout, in that case
the SCSI layer will abort and re-issue the command. USB storage has no
internal timeout, it relies on SCSI layer aborting commands via
.eh_abort_handler() for non those responsive devices.

After two consecutive timeouts of the same command, SCSI layer calls
.eh_device_reset_handler(), without calling .eh_abort_handler() first.

With usb-storage, this causes a deadlock:

  -> .eh_device_reset_handler
    -> device_reset
      -> mutex_lock(&(us->dev_mutex));

mutex already by usb_stor_control_thread(), which is waiting for
command completion:

  -> usb_stor_control_thread (mutex taken here)
    -> usb_stor_invoke_transport
      -> usb_stor_Bulk_transport
        -> usb_stor_bulk_srb
	  -> usb_stor_bulk_transfer_sglist
	    -> usb_sg_wait

Make sure we cancel any pending command in .eh_device_reset_handler()
to avoid this.

Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Cc: linux-usb@vger.kernel.org
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/all/ZEllnjMKT8ulZbJh@sakura/
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20230505114759.1189741-1-mbizon@freebox.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2023-05-13 18:53:03 +09:00

alauda.c

usb: storage: Add check for kcalloc

2022-12-08 16:43:12 +01:00

cypress_atacb.c

scsi: core: Remove the cmd field from struct scsi_request

2022-03-01 22:21:49 -05:00

datafab.c

usb: storage: datafab: remove redundant assignment of variable result

2021-04-22 10:52:10 +02:00

debug.c

scsi: Remove drivers/scsi/scsi.h