Commit 181a9a04 authored Apr 03, 2014 by Zongxun Wang Committed by Linus Torvalds Apr 03, 2014

ocfs2: fix null pointer dereference when access dlm_state before launching dlm thread



When mounting an ocfs2 volume, it will firstly generate a file
/sys/kernel/debug/o2dlm/<uuid>/dlm_state, and then launch the dlm thread.
So the following situation will cause a null pointer dereference.
dlm_debug_init -> access file dlm_state which will call dlm_state_print ->
dlm_launch_thread

Move dlm_debug_init after dlm_launch_thread and dlm_launch_recovery_thread
can fix this issue.

Signed-off-by: Zongxun Wang <wangzongxun@huawei.com>
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 0c3d1d62

fs/ocfs2/dlm/dlmdomain.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -1877,19 +1877,19 @@ static int dlm_join_domain(struct dlm_ctxt *dlm)
		goto bail;
		}

		status = dlm_debug_init(dlm);
		status = dlm_launch_thread(dlm);
		if (status < 0) {
		mlog_errno(status);
		goto bail;
		}

		status = dlm_launch_thread(dlm);
		status = dlm_launch_recovery_thread(dlm);
		if (status < 0) {
		mlog_errno(status);
		goto bail;
		}

		status = dlm_launch_recovery_thread(dlm);
		status = dlm_debug_init(dlm);
		if (status < 0) {
		mlog_errno(status);
		goto bail;

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