On Sun, Dec 25, 2011 at 10:43:09PM +0100, Thilo-Alexander Ginkel wrote: > Hi there, > > On Sat, Dec 17, 2011 at 10:55, Thilo-Alexander Ginkel <thilo@xxxxxxxxxx> wrote: > > There is a race condition involving acm_tty_hangup() and acm_tty_close() where > > hangup() would attempt to access tty->driver_data without proper locking and > > NULL checking after close() has potentially already set it to NULL. > > One possibility to (sporadically) trigger this behavior is to perform a > > suspend/resume cycle with a running WWAN data connection. > > > > This patch addresses the issue by introducing a NULL check for > > tty->driver_data in acm_tty_hangup() protected by open_mutex and exiting > > gracefully when hangup() is invoked on a device that has already been closed. > > just wondering: Is there any chance that this patch will make it into > 3.3? I would really appreciate that as the bug it fixes is pretty > annoying (and potentially causes data loss when the laptop locks up on > resume) and I am sure that I am not the only one affected by it (at > least all Lenovo T420s with an Ericsson F5521gw WWAN modem should be > similarly affected). > > If you would like to see any changes to the code or commit message > before considering the patch for inclusion, please let me know. As this isn't going to be an issue with 3.3 (from what I can tell, the code is correctly reworked in the patch set queued up for 3.3), I'll submit this for only the 3.2 and older kernel -stable releases, as that is the only place this should be relevant for. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
