Forwarded: Testing for netrom: fix KASAN slab-use-after-free in nr_dec_obs()

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Subject: Testing for netrom: fix KASAN slab-use-after-free in nr_dec_obs()
Author: activprithvi@gmail.com

#syz test upstream be548645527a131a097fdc884b7fca40c8b86231

Signed-off-by: Prithvi Tambewagh <activprithvi@gmail.com>
---
 net/netrom/nr_route.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c
index b94cb2ffbaf8..f84227acbf68 100644
--- a/net/netrom/nr_route.c
+++ b/net/netrom/nr_route.c
@@ -466,10 +466,12 @@ static int nr_dec_obs(void)
 				nr_neigh = s->routes[i].neighbour;
 
 				nr_neigh->count--;
-				nr_neigh_put(nr_neigh);
 
 				if (nr_neigh->count == 0 && !nr_neigh->locked)
 					nr_remove_neigh(nr_neigh);
+				else
+					nr_neigh_put(nr_neigh);
+
 
 				s->count--;
 

base-commit: be548645527a131a097fdc884b7fca40c8b86231
-- 
2.34.1