From 2fd60da46da76948b8cc561ae8cc902209686253 Mon Sep 17 00:00:00 2001 From: Peng Wang Date: Mon, 8 Jul 2019 23:16:11 +0800 Subject: [PATCH] kernfs: fix potential null pointer dereference Get root safely after kn is ensureed to be not null. Signed-off-by: Peng Wang Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20190708151611.13242-1-rocking@whu.edu.cn Signed-off-by: Greg Kroah-Hartman --- fs/kernfs/dir.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index a387534c9577..ddf537923a0a 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -430,7 +430,6 @@ struct kernfs_node *kernfs_get_active(struct kernfs_node *kn) */ void kernfs_put_active(struct kernfs_node *kn) { - struct kernfs_root *root = kernfs_root(kn); int v; if (unlikely(!kn)) @@ -442,7 +441,7 @@ void kernfs_put_active(struct kernfs_node *kn) if (likely(v != KN_DEACTIVATED_BIAS)) return; - wake_up_all(&root->deactivate_waitq); + wake_up_all(&kernfs_root(kn)->deactivate_waitq); } /** -- 2.45.2