Commit 44ebe791 authored Jun 17, 2017 by Wei Wang Committed by David S. Miller Jun 17, 2017

net: add debug atomic_inc_not_zero() in dst_hold()



This patch is meant to add a debug warning on the situation where dst is
being held during its destroy phase. This could potentially cause double
free issue on the dst.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 1eb04e7c

include/net/dst.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -251,7 +251,7 @@ static inline void dst_hold(struct dst_entry *dst)
		* __pad_to_align_refcnt declaration in struct dst_entry
		*/
		BUILD_BUG_ON(offsetof(struct dst_entry, __refcnt) & 63);
		atomic_inc(&dst->__refcnt);
		WARN_ON(atomic_inc_not_zero(&dst->__refcnt) == 0);
		}

		static inline void dst_use(struct dst_entry *dst, unsigned long time)