On Fri, Jan 15, 2016 at 3:38 PM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: > On Fri, Jan 15, 2016 at 2:51 PM, Takashi Iwai <tiwai@xxxxxxx> wrote: >> On Fri, 15 Jan 2016 12:03:17 +0100, >> Dmitry Vyukov wrote: >>> >>> On Fri, Jan 15, 2016 at 12:00 PM, Takashi Iwai <tiwai@xxxxxxx> wrote: >>> > On Fri, 15 Jan 2016 09:06:10 +0100, >>> > Dmitry Vyukov wrote: >>> >> >>> >> On Thu, Jan 14, 2016 at 5:09 PM, Takashi Iwai <tiwai@xxxxxxx> wrote: >>> >> > On Wed, 13 Jan 2016 21:54:10 +0100, >>> >> > Takashi Iwai wrote: >>> >> >> >>> >> >> OK, then this might be a possible race at the current snd_timer_stop() >>> >> >> implementation. There is no sync action there, so the ISR might be >>> >> >> still alive after snd_timer_close() call. Or might be another race. >>> >> >> This pattern looks a bit different, as it's involved with hrtimer. >>> >> >> >>> >> >> I'll take a look at it tomorrow. >>> >> > >>> >> > I've audited the code today, but the open window doesn't look like >>> >> > what I expected. I found only some possible cases with slave timer >>> >> > instances. >>> >> > >>> >> > In anyway, below is a test fix patch. Since I couldn't reproduce the >>> >> > issue on my local machines, it's hard to say whether this covers the >>> >> > holes you fell. Let's see... >>> >> >>> >> >>> >> Hi Takashi, >>> >> >>> >> I would be interested to understand why other people can't reproduce >>> >> issues that I hit pretty reliably. >>> >> I suspect that it can be due to .config. Please try with the following >>> >> config values. >>> > >>> > I guess rather other config, e.g. the kernel debug options. >>> > I suppose you enabled KASAN and DEBUG_LIST. What else? >>> >>> I've attached my config (you will need to disable CONFIG_KCOV, it is >>> not upstreamed). >> >> Hm, that has lots of other drivers built-in... >> >>> >> I also start qemu with "-soundhw all" arg. >>> > >>> > OK, so you're testing with VM? This makes easier to recheck. >>> >>> Yes, I start qemu as: >>> >>> qemu-system-x86_64 -hda wheezy.img -net >>> user,host=10.0.2.10,hostfwd=tcp::10022-:22 -net nic -nographic -kernel >>> arch/x86/boot/bzImage -append "console=ttyS0 root=/dev/sda debug >>> earlyprintk=serial slub_debug=UZ" -enable-kvm -m 2G -numa >>> node,nodeid=0,cpus=0-1 -numa node,nodeid=1,cpus=2-3 -smp >>> sockets=2,cores=2,threads=1 -usb -usbdevice mouse -usbdevice tablet >>> -soundhw all >> >> And which test did trigger use-after-free, even with all previous >> patches? > > I will try to extract a new reproducer now. Ok, I does not seem to see any crashes except the timer hangs below. Let's consider all other bugs as fixed. I will report anything new that I see separately. > Meanwhile, can you try to reproduce this one: > https://groups.google.com/forum/#!msg/syzkaller/bbtG9_h1ONU/CPLblMC6FAAJ > ? I run the program in a tight parallel loop. _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
