Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1630390

Re: [PATCH v2] usb: core: Warn if an URB's transfer_buffer is on stack

Show all headers | View raw

> +			} else if (object_is_on_stack(urb->transfer_buffer)) {
> +				WARN_ONCE(1, "transfer buffer is on stack\n");
> +				ret = -EAGAIN;
>  			} else {

Hi,

Has anyone considered a fail-safe mode? I.e.: if a buffer is on stack,
kmemdup it and continue with a warning. This will give us both: functional
drivers (with possibly decreased efficiency in speed and memory footprint)
and warnings for developers that a particular driver requires attention.

This mode will not affect drivers which obey the rules, but will make
offenders at least functional. My main concern is that not every user is able
to detect and report a problem, which prevents drivers from functioning.
Especially this is a problem for not wide spread devices.
Due to this users a seeing unusable equipment, but developers are not
aware of those, even if fixes are trivial.

Such mode has a also a negative effect: if a developer has a device
with an offending driver, he can miss the warning message, since the driver
just works.

Regards,
Maksim.

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH v2] usb: core: Warn if an URB's transfer_buffer is on stack Florian Fainelli <f.fainelli@gmail.com> - 2017-04-24 03:40 +0200
  Re: [PATCH v2] usb: core: Warn if an URB's transfer_buffer is on  stack Clemens Ladisch <clemens@ladisch.de> - 2017-04-24 09:30 +0200
  Re: [PATCH v2] usb: core: Warn if an URB's transfer_buffer is on  stack Alan Stern <stern@rowland.harvard.edu> - 2017-04-24 15:30 +0200
  Re: [PATCH v2] usb: core: Warn if an URB's transfer_buffer is on  stack Maksim Salau <maksim.salau@gmail.com> - 2017-04-25 12:40 +0200
    Re: [PATCH v2] usb: core: Warn if an URB's transfer_buffer is on  stack Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2017-04-25 14:00 +0200
      Re: [PATCH v2] usb: core: Warn if an URB's transfer_buffer is on stack Felipe Balbi <felipe.balbi@linux.intel.com> - 2017-04-25 15:30 +0200

csiph-web