net: print proper warning on dst underflow
Proper warnings with stack traces make it much easier to figure out
what's doing the double free and create more meaningful bug reports from
users.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/dst.c b/net/core/dst.c
index 1325316..193af52 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -172,7 +172,7 @@
int newrefcnt;
newrefcnt = atomic_dec_return(&dst->__refcnt);
- if (unlikely(newrefcnt < 0))
+ if (WARN_ONCE(newrefcnt < 0, "dst_release underflow"))
net_warn_ratelimited("%s: dst:%p refcnt:%d\n",
__func__, dst, newrefcnt);
if (!newrefcnt)
@@ -187,7 +187,7 @@
int newrefcnt;
newrefcnt = atomic_dec_return(&dst->__refcnt);
- if (unlikely(newrefcnt < 0))
+ if (WARN_ONCE(newrefcnt < 0, "dst_release_immediate underflow"))
net_warn_ratelimited("%s: dst:%p refcnt:%d\n",
__func__, dst, newrefcnt);
if (!newrefcnt)
