On Sat, 25 Nov 2006, Oliver Neukum wrote: > > > > By the way, you should be aware that creating an attribute file in the > > > > interface's device directory (like dev_attr_speed above) is inherently > > > > unsafe. A user process can open the file, hold it open while the > > > > driver > > > > is unloaded, and then try to read or write it -- causing an oops.
> OK, a bit more elaborate. > > 1. add a list to struct attribute > 2. add any struct sysfs_buffer opened to that list > 3. in class_device_remove_file walk this list and mark all buffers on a list > orphaned > 4. in fill_read_buffer check this flag an fail if need (the operation is > already under lock) Actually, I think that might work. You'd have to add a pointer from the sysfs_buffer to the struct file or the dentry, so that you could tell which buffers belonged to the device whose file was being removed. And you'd have to synchronize walking the list with opening & closing attribute files, which could turn out to be prohibitively difficult. Greg, what do you think? Alan Stern ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
