• J
    rbtree: fix rbtree_postorder_for_each_entry_safe() iterator · 1310a5a9
    Jan Kara 提交于
    The iterator rbtree_postorder_for_each_entry_safe() relies on pointer
    underflow behavior when testing for loop termination.  In particular it
    expects that
    
      &rb_entry(NULL, type, field)->field
    
    is NULL.  But the result of this expression is not defined by a C standard
    and some gcc versions (e.g.  4.3.4) assume the above expression can never
    be equal to NULL.  The net result is an oops because the iteration is not
    properly terminated.
    
    Fix the problem by modifying the iterator to avoid pointer underflows.
    Signed-off-by: NJan Kara <jack@suse.cz>
    Signed-off-by: NCody P Schafer <cody@linux.vnet.ibm.com>
    Cc: Michel Lespinasse <walken@google.com>
    Cc: "David S. Miller" <davem@davemloft.net>
    Cc: Adrian Hunter <adrian.hunter@intel.com>
    Cc: Artem Bityutskiy <dedekind1@gmail.com>
    Cc: David Woodhouse <dwmw2@infradead.org>
    Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
    Cc: Pablo Neira Ayuso <pablo@netfilter.org>
    Cc: Patrick McHardy <kaber@trash.net>
    Cc: Paul Mundt <lethal@linux-sh.org>
    Cc: Theodore Ts'o <tytso@mit.edu>
    Cc: <stable@vger.kernel.org>		[3.12.x]
    Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
    1310a5a9
rbtree.h 3.7 KB