linux-kernel - Re: Mutual debugging of 2 processes can stuck in unkillable stopped state

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 12 Apr 2021 10:25:06 +0300
From:   Igor Zhbanov <i.zhbanov@...russia.ru>
To:     Oleg Nesterov <oleg@...hat.com>
CC:     <linux-trace-devel@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: Re: Mutual debugging of 2 processes can stuck in unkillable stopped
 state

Hi Oleg,

So what is the cause of this problem?

Thank you.

On 29.03.2021 20:44, Igor Zhbanov wrote:
> 
> Here is the processes stack before sending any signals to them:
> 
> izh@...e2:~> sudo cat /proc/1751/stack
> [<0>] ptrace_stop+0x14e/0x260
> [<0>] ptrace_do_notify+0x91/0xb0
> [<0>] ptrace_notify+0x4e/0x70
> [<0>] syscall_slow_exit_work+0x90/0x150
> [<0>] do_syscall_64+0x129/0x1f0
> [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> 
> izh@...e2:~> sudo cat /proc/1979/stack
> [<0>] ptrace_stop+0x14e/0x260
> [<0>] get_signal+0x4d5/0x840
> [<0>] do_signal+0x30/0x6a0
> [<0>] exit_to_usermode_loop+0x8b/0x120
> [<0>] do_syscall_64+0x1c3/0x1f0
> [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
> 
>> Igor, thanks for your report, but (I think) this has nothing to do
>> with mutual debugging. I'll return to this problem in a couple of
>> days, I'm a bit busy right now.