From ba7c95ea3870fe7b847466d39a049ab6f156aa2c Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Tue, 24 Mar 2015 09:53:17 +1100 Subject: rhashtable: Fix sleeping inside RCU critical section in walk_stop The commit 963ecbd41a1026d99ec7537c050867428c397b89 ("rhashtable: Fix use-after-free in rhashtable_walk_stop") fixed a real bug but created another one because we may end up sleeping inside an RCU critical section. This patch fixes it properly by replacing the mutex with a spin lock that specifically protects the walker lists. Reported-by: Sasha Levin Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- include/linux/rhashtable.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h index f9ecf32bce55..d7be9cb0e91f 100644 --- a/include/linux/rhashtable.h +++ b/include/linux/rhashtable.h @@ -133,6 +133,7 @@ struct rhashtable_params { * @p: Configuration parameters * @run_work: Deferred worker to expand/shrink asynchronously * @mutex: Mutex to protect current/future table swapping + * @lock: Spin lock to protect walker list * @being_destroyed: True if table is set up for destruction */ struct rhashtable { @@ -144,6 +145,7 @@ struct rhashtable { struct rhashtable_params p; struct work_struct run_work; struct mutex mutex; + spinlock_t lock; }; /** -- cgit v1.3-14-g43fede