[IMA] Re: possible deadlock in get_user_pages_unlocked (2)

2019-06-10 Thread Eric Biggers
On Tue, Jun 04, 2019 at 06:16:00PM -0700, syzbot wrote: > syzbot has bisected this bug to: > > commit 69d61f577d147b396be0991b2ac6f65057f7d445 > Author: Mimi Zohar > Date: Wed Apr 3 21:47:46 2019 + > > ima: verify mprotect change is consistent with mmap policy > > bisection log: http

Re: possible deadlock in get_user_pages_unlocked (2)

2019-06-04 Thread syzbot
syzbot has bisected this bug to: commit 69d61f577d147b396be0991b2ac6f65057f7d445 Author: Mimi Zohar Date: Wed Apr 3 21:47:46 2019 + ima: verify mprotect change is consistent with mmap policy bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1055a2f2a0 start commit: 5

Re: possible deadlock in get_user_pages_unlocked (2)

2019-06-04 Thread syzbot
syzbot has found a reproducer for the following crash on: HEAD commit:56b697c6 Add linux-next specific files for 20190604 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=13241716a0 kernel config: https://syzkaller.appspot.com/x/.config?x=4248d6bc70076

possible deadlock in get_user_pages_unlocked (2)

2019-05-31 Thread syzbot
Hello, syzbot found the following crash on: HEAD commit:3c09c195 Add linux-next specific files for 20190531 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=13b36b9aa0 kernel config: https://syzkaller.appspot.com/x/.config?x=6cfb24468280cd5c dashboard

Re: possible deadlock in get_user_pages_unlocked

2018-03-09 Thread Eric Biggers
On Fri, Feb 09, 2018 at 07:19:25PM -0800, Eric Biggers wrote: > Hi Al, > > On Sat, Feb 10, 2018 at 01:36:40AM +, Al Viro wrote: > > On Fri, Feb 02, 2018 at 09:57:27AM +0100, Dmitry Vyukov wrote: > > > > > syzbot tests for up to 5 minutes. However, if there is a race involved > > > then you ma

Re: possible deadlock in get_user_pages_unlocked

2018-02-09 Thread Eric Biggers
Hi Al, On Sat, Feb 10, 2018 at 01:36:40AM +, Al Viro wrote: > On Fri, Feb 02, 2018 at 09:57:27AM +0100, Dmitry Vyukov wrote: > > > syzbot tests for up to 5 minutes. However, if there is a race involved > > then you may need more time because the crash is probabilistic. > > But from what I see

Re: possible deadlock in get_user_pages_unlocked

2018-02-09 Thread Al Viro
On Fri, Feb 02, 2018 at 09:57:27AM +0100, Dmitry Vyukov wrote: > syzbot tests for up to 5 minutes. However, if there is a race involved > then you may need more time because the crash is probabilistic. > But from what I see most of the time, if one can't reproduce it > easily, it's usually due to

Re: possible deadlock in get_user_pages_unlocked

2018-02-02 Thread Dmitry Vyukov
On Fri, Feb 2, 2018 at 7:20 AM, Al Viro wrote: > On Fri, Feb 02, 2018 at 05:46:26AM +, Al Viro wrote: >> On Thu, Feb 01, 2018 at 09:35:02PM -0800, Eric Biggers wrote: >> >> > Try starting up multiple instances of the program; that sometimes helps >> > with >> > these races that are hard to hi

Re: possible deadlock in get_user_pages_unlocked

2018-02-01 Thread Al Viro
On Fri, Feb 02, 2018 at 05:46:26AM +, Al Viro wrote: > On Thu, Feb 01, 2018 at 09:35:02PM -0800, Eric Biggers wrote: > > > Try starting up multiple instances of the program; that sometimes helps with > > these races that are hard to hit (since you may e.g. have a different > > number of > > C

Re: possible deadlock in get_user_pages_unlocked

2018-02-01 Thread Al Viro
On Thu, Feb 01, 2018 at 09:35:02PM -0800, Eric Biggers wrote: > Try starting up multiple instances of the program; that sometimes helps with > these races that are hard to hit (since you may e.g. have a different number > of > CPUs than syzbot used). If I start up 4 instances I see the lockdep s

Re: possible deadlock in get_user_pages_unlocked

2018-02-01 Thread Eric Biggers
On Fri, Feb 02, 2018 at 04:50:20AM +, Al Viro wrote: > On Thu, Feb 01, 2018 at 04:58:00PM -0800, syzbot wrote: > > Hello, > > > > syzbot hit the following crash on upstream commit > > 7109a04eae81c41ed529da9f3c48c3655ccea741 (Thu Feb 1 17:37:30 2018 +) > > Merge git://git.kernel.org/pub/sc

Re: possible deadlock in get_user_pages_unlocked

2018-02-01 Thread Al Viro
On Thu, Feb 01, 2018 at 04:58:00PM -0800, syzbot wrote: > Hello, > > syzbot hit the following crash on upstream commit > 7109a04eae81c41ed529da9f3c48c3655ccea741 (Thu Feb 1 17:37:30 2018 +) > Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide > > So far this crash happened 2 times