linux/fs/ocfs2/dlm
Yiwen Jiang f57a22ddec ocfs2: avoid access invalid address when read o2dlm debug messages
The following case will lead to a lockres is freed but is still in use.

cat /sys/kernel/debug/o2dlm/locking_state	dlm_thread
lockres_seq_start
    -> lock dlm->track_lock
    -> get resA
                                                resA->refs decrease to 0,
                                                call dlm_lockres_release,
                                                and wait for "cat" unlock.
Although resA->refs is already set to 0,
increase resA->refs, and then unlock
                                                lock dlm->track_lock
                                                    -> list_del_init()
                                                    -> unlock
                                                    -> free resA

In such a race case, invalid address access may occurs.  So we should
delete list res->tracking before resA->refs decrease to 0.

Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
..
dlmapi.h
dlmast.c o2dlm: fix NULL pointer dereference in o2dlm_blocking_ast_wrapper 2015-02-10 14:30:30 -08:00
dlmcommon.h ocfs2/dlm: cleanup unused function __dlm_wait_on_lockres_flags_set 2015-06-24 17:49:39 -07:00
dlmconvert.c
dlmconvert.h
dlmdebug.c ocfs2: fix snprintf format specifier in dlmdebug.c 2015-02-10 14:30:29 -08:00
dlmdebug.h
dlmdomain.c ocfs2: optimize error handling in dlm_request_join 2015-09-04 16:54:41 -07:00
dlmdomain.h ocfs2: dlm: dlmdomain: remove unused function 2015-02-10 14:30:29 -08:00
dlmlock.c ocfs2: remove NULL assignments on static 2014-06-04 16:53:53 -07:00
dlmmaster.c ocfs2: avoid access invalid address when read o2dlm debug messages 2015-09-04 16:54:41 -07:00
dlmrecovery.c ocfs2/dlm: use list_for_each_entry instead of list_for_each 2015-09-04 16:54:41 -07:00
dlmthread.c ocfs2: avoid access invalid address when read o2dlm debug messages 2015-09-04 16:54:41 -07:00
dlmunlock.c ocfs2: fix deadlock when two nodes are converting same lock from PR to EX and idletimeout closes conn 2014-06-23 16:47:45 -07:00
Makefile ocfs2: remove versioning information 2014-01-21 16:19:41 -08:00