On Thu, Jun 13, 2019 at 05:44:15PM +0200, Takashi Iwai wrote:
On Thu, 13 Jun 2019 17:39:46 +0200, Sasha Levin wrote:On Thu, Jun 13, 2019 at 11:13:55AM +0200, Takashi Iwai wrote: >On Thu, 13 Jun 2019 11:11:22 +0200, >Greg Kroah-Hartman wrote: >> >> On Thu, Jun 13, 2019 at 11:02:54AM +0200, Takashi Iwai wrote: >> > On Thu, 13 Jun 2019 10:33:44 +0200, >> > Greg Kroah-Hartman wrote: >> > > >> > > [ Upstream commit feb689025fbb6f0aa6297d3ddf97de945ea4ad32 ] >> > > >> > > ALSA OSS sequencer calls the ioctl function indirectly via >> > > snd_seq_kernel_client_ctl(). While we already applied the protection >> > > against races between the normal ioctls and writes via the client's >> > > ioctl_mutex, this code path was left untouched. And this seems to be >> > > the cause of still remaining some rare UAF as spontaneously triggered >> > > by syzkaller. >> > > >> > > For the sake of robustness, wrap the ioctl_mutex also for the call via >> > > snd_seq_kernel_client_ctl(), too. >> > > >> > > Reported-by: syzbot+e4c8abb920efa77bace9@xxxxxxxxxxxxxxxxxxxxxxxxx >> > > Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> >> > > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> >> > >> > This commit is reverted later by commit f0654ba94e33. >> > So please drop this. The proper fix is done later by commit >> > 7c32ae35fbf9 ("ALSA: seq: Cover unsubscribe_port() in list_mutex") >> > >> > Ditto for 4.19.y and 5.1.y. >> >> Now dropped everywhere, and I added 7c32ae35fbf9 ("ALSA: seq: Cover >> unsubscribe_port() in list_mutex") everywhere instead. > >Thanks! > >BTW, do we have a systematic check whether the selected stable commit >is reverted in a later commit? At least, you can track it as long as >Fixes tag is properly set. I have that scripting in place, and I usually check it once before I send the initial reviews and then once Greg does the -rc release.OK, good to hear. So this time must be some exceptional error.
I still run these manually (I guess it's time to automate that too), so it happens sometimes that folks notice these faster :) -- Thanks, Sasha
