The patch titled
reparent_thread: fix the "is it traced" check
has been added to the -mm tree. Its filename is
reparent_thread-fix-the-is-it-traced-check.patch
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------------------------------------------------------
Subject: reparent_thread: fix the "is it traced" check
From: Oleg Nesterov <oleg@xxxxxxxxxx>
reparent_thread() uses ptrace_reparented() to check whether this thread is
ptraced, in that case we should not notify the new parent.
But ptrace_reparented() is not exactly correct when the reparented thread
is traced by /sbin/init, because forget_original_parent() has already
changed ->real_parent.
Currently, the only problem is the false notification. But with the next
patch the kernel crash in this (yes, pathological) case.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Roland McGrath <roland@xxxxxxxxxx>
Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/exit.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff -puN kernel/exit.c~reparent_thread-fix-the-is-it-traced-check kernel/exit.c
--- a/kernel/exit.c~reparent_thread-fix-the-is-it-traced-check
+++ a/kernel/exit.c
@@ -826,7 +826,7 @@ static void reparent_thread(struct task_
/* If we'd notified the old parent about this child's death,
* also notify the new parent.
*/
- if (!ptrace_reparented(p) &&
+ if (!p->ptrace &&
p->exit_state == EXIT_ZOMBIE && thread_group_empty(p))
do_notify_parent(p, p->exit_signal);
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
origin.patch
wait-prevent-exclusive-waiter-starvation.patch
linux-next.patch
pipe_rdwr_fasync-fix-the-error-handling-to-prevent-the-leak-crash.patch
get_mm_hiwater_xxx-trivial-s-define-inline.patch
getrusage-fill-ru_maxrss-value.patch
ptrace-kill-__ptrace_detach-fix-exit_state-check.patch
ptrace-simplify-ptrace_exit-ignoring_children-path.patch
ptrace-reintroduce-__ptrace_detach-as-a-callee-of-ptrace_exit.patch
ptrace-fix-possible-zombie-leak-on-ptrace_detach.patch
reparent_thread-dont-call-kill_orphaned_pgrp-if-task_detached.patch
reparent_thread-fix-the-is-it-traced-check.patch
reparent_thread-fix-a-zombie-leak-if-sbin-init-ignores-sigchld.patch
forget_original_parent-cleanup-ptrace-pathes.patch
kthread-dont-looking-for-a-task-in-create_kthread-2.patch
pids-document-task_pgrp-task_session-is-not-safe-without-tasklist-rcu.patch
pids-document-task_pgrp-task_session-is-not-safe-without-tasklist-rcu-fix.patch
pids-improve-get_task_pid-to-fix-the-unsafe-sys_wait4-task_pgrp.patch
pids-refactor-vnr-nr_ns-helpers-to-make-them-safe.patch
pids-kill-now-unused-signal_struct-__pgrp-__session-and-friends.patch
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