| Message ID | 20200910122105.13398-4-oneukum@suse.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [RFC,1/6] CDC-WDM: fix hangs in flush() | expand |
diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c index eee19532e67e..930000b1d43b 100644 --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -610,10 +610,14 @@ static int wdm_flush(struct file *file, fl_owner_t id) return -EIO; if (rv < 0) return -EINTR; + + spin_lock_irq(&desc->iuspin); rv = desc->werr; + desc->werr = 0; + spin_unlock_irq(&desc->iuspin); + if (rv < 0) - dev_err(&desc->intf->dev, "Error in flush path: %d\n", - rv); + dev_err(&desc->intf->dev, "Error in flush path: %d\n", rv); return usb_translate_errors(rv); }
In case a race was lost and multiple fds used, an error could be reported multiple times. To fix this a spinlock must be taken. Signed-off-by: Oliver Neukum <oneukum@suse.com> --- drivers/usb/class/cdc-wdm.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)