From: Maxime Bizon <mbizon@xxxxxxxxxx>
commit a398d5eac6984316e71474e25b975688f282379b upstream.
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@xxxxxxxxxx>
Cc: linux-usb@xxxxxxxxxxxxxxx
Cc: stable <stable@xxxxxxxxxx>
Link: https://lore.kernel.org/all/ZEllnjMKT8ulZbJh@sakura/
Reviewed-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230505114759.1189741-1-mbizon@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/storage/scsiglue.c | 28 +++++++++++++++++++++-------
1 file changed, 21 insertions(+), 7 deletions(-)
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -406,22 +406,25 @@ static DEF_SCSI_QCMD(queuecommand)
***********************************************************************/
/* Command timeout and abort */
-static int command_abort(struct scsi_cmnd *srb)
+static int command_abort_matching(struct us_data *us, struct scsi_cmnd *srb_match)
{
- struct us_data *us = host_to_us(srb->device->host);
-
- usb_stor_dbg(us, "%s called\n", __func__);
-
/*
* us->srb together with the TIMED_OUT, RESETTING, and ABORTING
* bits are protected by the host lock.
*/
scsi_lock(us_to_host(us));
- /* Is this command still active? */
- if (us->srb != srb) {
+ /* is there any active pending command to abort ? */
+ if (!us->srb) {
scsi_unlock(us_to_host(us));
usb_stor_dbg(us, "-- nothing to abort\n");
+ return SUCCESS;
+ }
+
+ /* Does the command match the passed srb if any ? */
+ if (srb_match && us->srb != srb_match) {
+ scsi_unlock(us_to_host(us));
+ usb_stor_dbg(us, "-- pending command mismatch\n");
return FAILED;
}
@@ -444,6 +447,14 @@ static int command_abort(struct scsi_cmn
return SUCCESS;
}
+static int command_abort(struct scsi_cmnd *srb)
+{
+ struct us_data *us = host_to_us(srb->device->host);
+
+ usb_stor_dbg(us, "%s called\n", __func__);
+ return command_abort_matching(us, srb);
+}
+
/*
* This invokes the transport reset mechanism to reset the state of the
* device
@@ -455,6 +466,9 @@ static int device_reset(struct scsi_cmnd
usb_stor_dbg(us, "%s called\n", __func__);
+ /* abort any pending command before reset */
+ command_abort_matching(us, NULL);
+
/* lock the device pointers and do the reset */
mutex_lock(&(us->dev_mutex));
result = us->transport_reset(us);
