Messages in this thread Patch in this message | | | Date | Mon, 10 May 2010 21:49:49 +0200 | From | Oleg Nesterov <> | Subject | [PATCH 1/4] INIT_TASK() should initialize ->thread_group list |
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The trivial /sbin/init doing
int main(void) { kill(0, SIGKILL) }
crashes the kernel.
This happens because __kill_pgrp_info(init_struct_pid) also sends SIGKILL to the swapper process which runs with the uninitialized ->thread_group.
Change INIT_TASK() to initialize ->thread_group properly.
Note: the real problem is that the swapper process must not be visible to signals, see the next patch. But this change is right anyway and fixes the crash.
Reported-and-tested-by: Mathias Krause <mathias.krause@secunet.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> ---
include/linux/init_task.h | 1 + 1 file changed, 1 insertion(+)
--- 34-rc1/include/linux/init_task.h~1_INIT_TASK_THREAD_GROUP 2010-05-10 19:44:19.000000000 +0200 +++ 34-rc1/include/linux/init_task.h 2010-05-10 19:45:27.000000000 +0200 @@ -172,6 +172,7 @@ extern struct cred init_cred; [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \ [PIDTYPE_SID] = INIT_PID_LINK(PIDTYPE_SID), \ }, \ + .thread_group = LIST_HEAD_INIT(tsk.thread_group), \ .dirties = INIT_PROP_LOCAL_SINGLE(dirties), \ INIT_IDS \ INIT_PERF_EVENTS(tsk) \
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