1. 23 6月, 2011 1 次提交
  2. 05 6月, 2011 1 次提交
  3. 31 3月, 2011 1 次提交
  4. 23 3月, 2011 1 次提交
    • T
      ptrace: Kill tracehook_notify_jctl() · edf2ed15
      Tejun Heo 提交于
      tracehook_notify_jctl() aids in determining whether and what to report
      to the parent when a task is stopped or continued.  The function also
      adds an extra requirement that siglock may be released across it,
      which is currently unused and quite difficult to satisfy in
      well-defined manner.
      
      As job control and the notifications are about to receive major
      overhaul, remove the tracehook and open code it.  If ever necessary,
      let's factor it out after the overhaul.
      
      * Oleg spotted incorrect CLD_CONTINUED/STOPPED selection when ptraced.
        Fixed.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Roland McGrath <roland@redhat.com>
      edf2ed15
  5. 28 10月, 2010 1 次提交
  6. 16 12月, 2009 1 次提交
    • O
      ptrace: change tracehook_report_syscall_exit() to handle stepping · 2f0edac5
      Oleg Nesterov 提交于
      Suggested by Roland.
      
      Change tracehook_report_syscall_exit() to look at step flag and send the
      trap signal if needed.
      
      This change affects ia64, microblaze, parisc, powerpc, sh.  They pass
      nonzero "step" argument to tracehook but since it was ignored the tracee
      reports via ptrace_notify(), this is not right and not consistent.
      
      	- PTRACE_SETSIGINFO doesn't work
      
      	- if the tracer resumes the tracee with signr != 0 the new signal
      	  is generated rather than delivering it
      
      	- If PT_TRACESYSGOOD is set the tracee reports the wrong exit_code
      
      I don't have a powerpc machine, but I think this test-case should see the
      difference:
      
      	#include <unistd.h>
      	#include <sys/ptrace.h>
      	#include <sys/wait.h>
      	#include <assert.h>
      	#include <stdio.h>
      
      	int main(void)
      	{
      		int pid, status;
      
      		if (!(pid = fork())) {
      			assert(ptrace(PTRACE_TRACEME) == 0);
      			kill(getpid(), SIGSTOP);
      
      			getppid();
      
      			return 0;
      		}
      
      		assert(pid == wait(&status));
      		assert(ptrace(PTRACE_SETOPTIONS, pid, 0, PTRACE_O_TRACESYSGOOD) == 0);
      
      		assert(ptrace(PTRACE_SYSCALL, pid, 0,0) == 0);
      		assert(pid == wait(&status));
      
      		assert(ptrace(PTRACE_SINGLESTEP, pid, 0,0) == 0);
      		assert(pid == wait(&status));
      
      		if (status == 0x57F)
      			return 0;
      
      		printf("kernel bug: status=%X shouldn't have 0x80\n", status);
      		return 1;
      	}
      Signed-off-by: NOleg Nesterov <oleg@redhat.com>
      Acked-by: NRoland McGrath <roland@redhat.com>
      Cc: <linux-arch@vger.kernel.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2f0edac5
  7. 24 9月, 2009 1 次提交
    • R
      signals: tracehook_notify_jctl change · ae6d2ed7
      Roland McGrath 提交于
      This changes tracehook_notify_jctl() so it's called with the siglock held,
      and changes its argument and return value definition.  These clean-ups
      make it a better fit for what new tracing hooks need to check.
      
      Tracing needs the siglock here, held from the time TASK_STOPPED was set,
      to avoid potential SIGCONT races if it wants to allow any blocking in its
      tracing hooks.
      
      This also folds the finish_stop() function into its caller
      do_signal_stop().  The function is short, called only once and only
      unconditionally.  It aids readability to fold it in.
      
      [oleg@redhat.com: do not call tracehook_notify_jctl() in TASK_STOPPED state]
      [oleg@redhat.com: introduce tracehook_finish_jctl() helper]
      Signed-off-by: NRoland McGrath <roland@redhat.com>
      Signed-off-by: NOleg Nesterov <oleg@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ae6d2ed7
  8. 19 6月, 2009 1 次提交
  9. 05 6月, 2009 1 次提交
    • O
      ptrace: tracehook_report_clone: fix false positives · 087eb437
      Oleg Nesterov 提交于
      The "trace || CLONE_PTRACE" check in tracehook_report_clone() is not right,
      
      - If the untraced task does clone(CLONE_PTRACE) the new child is not traced,
        we must not queue SIGSTOP.
      
      - If we forked the traced task, but the tracer exits and untraces both the
        forking task and the new child (after copy_process() drops tasklist_lock),
        we should not queue SIGSTOP too.
      
      Change the code to check task_ptrace() != 0 instead. This is still racy, but
      the race is harmless.
      
      We can race with another tracer attaching to this child, or the tracer can
      exit and detach in parallel. But giwen that we didn't do wake_up_new_task()
      yet, the child must have the pending SIGSTOP anyway.
      Signed-off-by: NOleg Nesterov <oleg@redhat.com>
      Acked-by: NRoland McGrath <roland@redhat.com>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      087eb437
  10. 03 4月, 2009 2 次提交
    • O
      tracehook_notify_death: use task_detached() helper · bb24c679
      Oleg Nesterov 提交于
      Now that task_detached() is exported, change tracehook_notify_death() to
      use this helper, nobody else checks ->exit_signal == -1 by hand.
      Signed-off-by: NOleg Nesterov <oleg@redhat.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: "Metzger, Markus T" <markus.t.metzger@intel.com>
      Acked-by: NRoland McGrath <roland@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      bb24c679
    • O
      signals: remove 'handler' parameter to tracehook functions · 43918f2b
      Oleg Nesterov 提交于
      Container-init must behave like global-init to processes within the
      container and hence it must be immune to unhandled fatal signals from
      within the container (i.e SIG_DFL signals that terminate the process).
      
      But the same container-init must behave like a normal process to processes
      in ancestor namespaces and so if it receives the same fatal signal from a
      process in ancestor namespace, the signal must be processed.
      
      Implementing these semantics requires that send_signal() determine pid
      namespace of the sender but since signals can originate from workqueues/
      interrupt-handlers, determining pid namespace of sender may not always be
      possible or safe.
      
      This patchset implements the design/simplified semantics suggested by
      Oleg Nesterov.  The simplified semantics for container-init are:
      
      	- container-init must never be terminated by a signal from a
      	  descendant process.
      
      	- container-init must never be immune to SIGKILL from an ancestor
      	  namespace (so a process in parent namespace must always be able
      	  to terminate a descendant container).
      
      	- container-init may be immune to unhandled fatal signals (like
      	  SIGUSR1) even if they are from ancestor namespace. SIGKILL/SIGSTOP
      	  are the only reliable signals to a container-init from ancestor
      	  namespace.
      
      This patch:
      
      Based on an earlier patch submitted by Oleg Nesterov and comments from
      Roland McGrath (http://lkml.org/lkml/2008/11/19/258).
      
      The handler parameter is currently unused in the tracehook functions.
      Besides, the tracehook functions are called with siglock held, so the
      functions can check the handler if they later need to.
      
      Removing the parameter simiplifies changes to sig_ignored() in a follow-on
      patch.
      Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
      Acked-by: NRoland McGrath <roland@redhat.com>
      Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Daniel Lezcano <daniel.lezcano@free.fr>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      43918f2b
  11. 06 9月, 2008 1 次提交
  12. 08 8月, 2008 1 次提交
    • R
      tracehook: fix CLONE_PTRACE · 5861bbfc
      Roland McGrath 提交于
      In the change in commit 09a05394, I
      overlooked two nits in the logic and this broke using CLONE_PTRACE
      when PTRACE_O_TRACE* are not being used.
      
      A parent that is itself traced at all but not using PTRACE_O_TRACE*,
      using CLONE_PTRACE would have its new child fail to be traced.
      
      A parent that is not itself traced at all that uses CLONE_PTRACE
      (which should be a no-op in this case) would confuse the bookkeeping
      and lead to a crash at exit time.
      
      This restores the missing checks and fixes both failure modes.
      Reported-by: NEduardo Habkost <ehabkost@redhat.com>
      Signed-off-by: NRoland McGrath <roland@redhat.com>
      5861bbfc
  13. 05 8月, 2008 1 次提交
  14. 02 8月, 2008 1 次提交
  15. 27 7月, 2008 19 次提交