Re: BUG: soft lockup in snd_virmidi_output_trigger

2018-07-26 Thread Dae R. Jeong
regards, Dae R. Jeong > On Fri, 27 Jul 2018 06:13:22 +0200, > Dae R. Jeong wrote: > > > > I tested it and it worked. > > Thanks a lot! > > Good to hear. Below is the final patch with a proper comment (and > with syzbot reported-by, too) I'm going to queue

BUG: soft lockup in snd_virmidi_output_trigger

2018-07-25 Thread Dae R. Jeong
Reporting the crash: BUG: soft lockup in snd_virmidi_output_trigger This crash has been found in v4.18-rc3 using RaceFuzzer (a modified version of Syzkaller), which we describe more at the end of this report. Note that this bug is previously reported by Syzkaller a few month ago.

Re: BUG: soft lockup in snd_virmidi_output_trigger

2018-07-26 Thread Dae R. Jeong
On Thu, Jul 26, 2018 at 02:50:25PM +0200, Takashi Iwai wrote: > On Thu, 26 Jul 2018 07:53:26 +0200, > Dae R. Jeong wrote: > > > > Reporting the crash: BUG: soft lockup in snd_virmidi_output_trigger > > > > This crash has been found in v4.18-rc3 using Race

KASAN: null-ptr-deref Write in binder_update_page_range

2018-08-22 Thread Dae R. Jeong
Reporting the crash: KASAN: null-ptr-deref Write in binder_update_page_range This crash has been found in v4.18-rc3 using RaceFuzzer (a modified version of Syzkaller), which we describe more at the end of this report. Our analysis shows that the race occurs when invoking two syscalls

Re: KASAN: null-ptr-deref Write in binder_update_page_range

2018-08-23 Thread Dae R. Jeong
> Could you test this patch? I found that bug a month ago but didn't submit > yet. I don't have a reproducer now. I manually analzed a root cause of the crash using a fuzzer's log. The log reported a race on 'alloc->vma'. Because I don't have a reproducer, I can't test the patch. I'm sorry.

WARNING in port_delete

2018-07-23 Thread Dae R. Jeong
Reporting the crash: WARNING in port_delete This crash has been found in v4.18-rc3 using RaceFuzzer (a modified version of Syzkaller), which we descrbie more at the end of this report. Our analysis shows that the race occurs when invoking two close syscalls concurrently. The executed program is

KASAN: use-after-free Read in link_path_walk

2018-07-23 Thread Dae R. Jeong
Reporting the crash: KASAN: use-after-free Read in link_path_walk This crash has been found in v4.17-rc1 using RaceFuzzer (a modified version of Syzkaller), which we describe more at the end of this report. Our analysis shows that the race occurs when invoking two syscalls concurrently, open()

Re: WARNING in md_ioctl

2020-10-21 Thread Dae R. Jeong
ck(>open_mutex); > > > sync_blockdev(bdev); > > > > > Good catch! The fix looks good. Would you like to submit a patch for it? Sure. I will send a patch soon. Best regards, Dae R. Jeong.

[PATCH] md: fix a warning caused by a race between concurrent md_ioctl()s

2020-10-21 Thread Dae R. Jeong
returning immediately if the MD_CLOSING bit is set in >flags which indicates that the array is being closed. Fixes: 065e519e71b2 ("md: MD_CLOSING needs to be cleared after called md_set_readonly or do_md_stop") Reported-by: syzbot+1e46a0864c1a6e9bd...@syzkaller.appspotmail.com Signe

Re: BUG: soft lockup in snd_virmidi_output_trigger

2018-07-26 Thread Dae R. Jeong
On Thu, Jul 26, 2018 at 02:50:25PM +0200, Takashi Iwai wrote: > On Thu, 26 Jul 2018 07:53:26 +0200, > Dae R. Jeong wrote: > > > > Reporting the crash: BUG: soft lockup in snd_virmidi_output_trigger > > > > This crash has been found in v4.18-rc3 using Race

Re: BUG: soft lockup in snd_virmidi_output_trigger

2018-07-26 Thread Dae R. Jeong
regards, Dae R. Jeong > On Fri, 27 Jul 2018 06:13:22 +0200, > Dae R. Jeong wrote: > > > > I tested it and it worked. > > Thanks a lot! > > Good to hear. Below is the final patch with a proper comment (and > with syzbot reported-by, too) I'm going to queue

KASAN: null-ptr-deref Write in binder_update_page_range

2018-08-22 Thread Dae R. Jeong
Reporting the crash: KASAN: null-ptr-deref Write in binder_update_page_range This crash has been found in v4.18-rc3 using RaceFuzzer (a modified version of Syzkaller), which we describe more at the end of this report. Our analysis shows that the race occurs when invoking two syscalls

Re: KASAN: null-ptr-deref Write in binder_update_page_range

2018-08-23 Thread Dae R. Jeong
> Could you test this patch? I found that bug a month ago but didn't submit > yet. I don't have a reproducer now. I manually analzed a root cause of the crash using a fuzzer's log. The log reported a race on 'alloc->vma'. Because I don't have a reproducer, I can't test the patch. I'm sorry.

WARNING in port_delete

2018-07-23 Thread Dae R. Jeong
Reporting the crash: WARNING in port_delete This crash has been found in v4.18-rc3 using RaceFuzzer (a modified version of Syzkaller), which we descrbie more at the end of this report. Our analysis shows that the race occurs when invoking two close syscalls concurrently. The executed program is

KASAN: use-after-free Read in link_path_walk

2018-07-23 Thread Dae R. Jeong
Reporting the crash: KASAN: use-after-free Read in link_path_walk This crash has been found in v4.17-rc1 using RaceFuzzer (a modified version of Syzkaller), which we describe more at the end of this report. Our analysis shows that the race occurs when invoking two syscalls concurrently, open()

BUG: soft lockup in snd_virmidi_output_trigger

2018-07-25 Thread Dae R. Jeong
Reporting the crash: BUG: soft lockup in snd_virmidi_output_trigger This crash has been found in v4.18-rc3 using RaceFuzzer (a modified version of Syzkaller), which we describe more at the end of this report. Note that this bug is previously reported by Syzkaller a few month ago.

WARNING in md_ioctl

2020-10-17 Thread Dae R. Jeong
rrect, this warning is introduced in the commit 065e519e("md: MD_CLOSING needs to be cleared after called md_set_readonly or do_md_stop"). Could you please take a look into this? Best regards, Dae R. Jeong

Re: WARNING in md_ioctl

2020-10-19 Thread Dae R. Jeong
d WARN_ON_ONCE()). As I am not familiar with this code, I do not see any other problem. Best regards, Dae R. Jeong