Home » Mailing list archives » linux-kernel » 2008 » June » 3

Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to fix a race

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
[view in full thread]
From: Roland McGrath
Subject: Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to fix a race
Date: Tuesday, June 3, 2008 - 2:01 pm

> It's definitely a bug in strace. For some reason (I don't care about)

What do you mean by "extra"?  There is a SIGTRAP sent after execve
completes when ptraced, even when PTRACE_SYSCALL is not being used.
So for an execve that succeeds under PTRACE_SYSCALL, there is a
ptrace_notify at syscall entry, then a SIGTRAP queued (i.e., not seen
by ptrace if blocked), then a ptrace_notify at syscall exit.  If
that's what's happening (including the blocked SIGTRAP not being seen
by the ptracer, i.e. strace), then there is no mystery (and no bug).


Thanks,
Roland
--
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
Messages in current thread:
[RFC PATCH] set TASK_TRACED before arch_ptrace code to fix ..., Luming Yu, (Wed May 21, 7:47 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Petr Tesarik, (Thu May 22, 1:47 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Thu May 22, 2:16 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Thu May 22, 4:18 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Petr Tesarik, (Thu May 22, 5:12 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Thu May 22, 6:24 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Thu May 22, 1:34 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Thu May 22, 1:39 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Thu May 22, 8:42 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Thu May 22, 9:19 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Thu May 22, 10:24 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Fri May 23, 5:33 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Sun May 25, 5:15 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Sun May 25, 6:30 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Mon May 26, 8:31 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Mon May 26, 9:04 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Mon May 26, 10:49 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Mon May 26, 11:12 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Petr Tesarik, (Mon May 26, 11:25 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Mon May 26, 11:34 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Tue May 27, 1:48 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Wed May 28, 2:14 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Fri May 30, 1:05 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Mon Jun 2, 11:02 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Mon Jun 2, 11:04 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Petr Tesarik, (Tue Jun 3, 2:01 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Petr Tesarik, (Tue Jun 3, 7:32 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Tue Jun 3, 2:01 pm)
RE: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luck, Tony, (Tue Jun 3, 2:31 pm)
RE: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Tue Jun 3, 3:13 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Tue Jun 3, 7:16 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Petr Tesarik, (Wed Jun 4, 2:16 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Wed Jun 4, 6:49 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Petr Tesarik, (Thu Jun 5, 4:16 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Thu Jun 5, 5:07 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Tue Jun 10, 1:23 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Mon Sep 8, 8:06 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Tue Sep 9, 10:55 pm)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Tue Sep 16, 1:50 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Roland McGrath, (Wed Sep 17, 10:01 am)
Re: [RFC PATCH] set TASK_TRACED before arch_ptrace code to ..., Luming Yu, (Wed Sep 17, 10:44 pm)