clk: Don't try to use a struct clk* after it could have been freed
authorTomeu Vizoso <tomeu.vizoso@collabora.com>
Tue, 2 Dec 2014 07:54:19 +0000 (08:54 +0100)
committerMichael Turquette <mturquette@linaro.org>
Wed, 3 Dec 2014 23:15:34 +0000 (15:15 -0800)
As __clk_release could call kfree on clk and then we wouldn't have a safe way
of getting the module that owns the clock.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Fixes: fcb0ee6a3d33 ("clk: Implement clk_unregister")
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
drivers/clk/clk.c

index 42f940f..609e9db 100644 (file)
@@ -2268,14 +2268,17 @@ int __clk_get(struct clk *clk)
 
 void __clk_put(struct clk *clk)
 {
+       struct module *owner;
+
        if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
                return;
 
        clk_prepare_lock();
+       owner = clk->owner;
        kref_put(&clk->ref, __clk_release);
        clk_prepare_unlock();
 
-       module_put(clk->owner);
+       module_put(owner);
 }
 
 /***        clk rate change notifiers        ***/