From 44ebe79149ff415e810529bf192faa5c38d4a0de Mon Sep 17 00:00:00 2001 From: Wei Wang Date: Sat, 17 Jun 2017 10:42:44 -0700 Subject: [PATCH] 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 Acked-by: Martin KaFai Lau Signed-off-by: David S. Miller --- include/net/dst.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/net/dst.h b/include/net/dst.h index d912b44d2dcb..f73611ec4017 100644 --- a/include/net/dst.h +++ b/include/net/dst.h @@ -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) -- 2.20.1