Greg, It is a problem because I use the pre-allocated buffer given by the layer usb-serial. Of course, I can create a new urb structure with a bigger buffer but I just suggest that using the buffer stored in the usb_serial_device seems to be logic and like a said, other driver use it without checking the buffer_size. Are you sure that the pl2303 is well protected against a buffer overflow ? What happens if a pl2303 device give a maxsize of 64 bytes like my device ? The driver will then make a buffer overflow and a kernel panic may occur. This was the module I used to study and write my own driver.
So I agree with the proposition of Oliver to add a buffer_size in the usb_serial_driver structure. This is very useful to prepare a buffer able to make bulk transfer. Regards, Alain -----Message d'origine----- De : Greg KH [mailto:[EMAIL PROTECTED] Envoyé : lundi 30 juillet 2007 17:04 À : [EMAIL PROTECTED] Cc : linux-usb-devel@lists.sourceforge.net Objet : Re: usb-serial.c question - potential Memory fault On Mon, Jul 30, 2007 at 07:10:55AM +0200, [EMAIL PROTECTED] wrote: > Hi Greg, > > After a new complete reading of my code against usb-serial.c, I finally > found ( I hope ) my problem. > In usb-serial.c, when bulk_in/out buffers are initialized, each ?buffer size > are the same as the wMaxPacketSize given by the endpoint. > So, in my case, my device have a value of 64 bytes and I send and receive > bulk data that might have 256 bytes length !!! And like pl2303, I just copy > the user data to port->write_urb->transfer_buffer. > For all driver that use usb-serial for the probe function, this can be a > problem (like for me). I have checked for example the pl2303 that never > check this value before the memcpy. Why is this a problem for you? You can use any size buffer you want if you wish to send more data than what the usb-serial core provides for you. Lots of other drivers do that today. thanks, greg k-h ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
