Commit 164c33c6 authored Jun 25, 2012 by Salman Qazi Committed by Ingo Molnar Jul 05, 2012

sched: Fix fork() error path to not crash



In dup_task_struct(), if arch_dup_task_struct() fails, the clean up
code fails to clean up correctly.  That's because the clean up
code depends on unininitalized ti->task pointer.  We fix this
by making sure that the task and thread_info know about each other
before we attempt to take the error path.

Signed-off-by: Salman Qazi <sqazi@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120626011815.11323.5533.stgit@dungbeetle.mtv.corp.google.com


Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent 9e85a6f9

kernel/fork.c

+8 −3

Original line number	Diff line number	Diff line
		@@ -304,12 +304,17 @@ static struct task_struct dup_task_struct(struct task_struct orig)
		}

		err = arch_dup_task_struct(tsk, orig);
		if (err)
		goto out;

		/*
		* We defer looking at err, because we will need this setup
		* for the clean up path to work correctly.
		*/
		tsk->stack = ti;

		setup_thread_stack(tsk, orig);

		if (err)
		goto out;

		clear_user_return_notifier(tsk);
		clear_tsk_need_resched(tsk);
		stackend = end_of_stack(tsk);

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