From 3e75a445537ab1a885912e5bf9643562189496c2 Mon Sep 17 00:00:00 2001 From: Bryan O'Donoghue Date: Sat, 2 Mar 2024 00:52:14 +0000 Subject: [PATCH] clk: Fix clk_core_get NULL dereference ANBZ: #8872 commit e97fe4901e0f59a0bfd524578fe3768f8ca42428 upstream. It is possible for clk_core_get to dereference a NULL in the following sequence: clk_core_get() of_clk_get_hw_from_clkspec() __of_clk_get_hw_from_provider() __clk_get_hw() __clk_get_hw() can return NULL which is dereferenced by clk_core_get() at hw->core. Prior to commit dde4eff47c82 ("clk: Look for parents with clkdev based clk_lookups") the check IS_ERR_OR_NULL() was performed which would have caught the NULL. Reading the description of this function it talks about returning NULL but that cannot be so at the moment. Update the function to check for hw before dereferencing it and return NULL if hw is NULL. Fixes: dde4eff47c82 ("clk: Look for parents with clkdev based clk_lookups") Signed-off-by: Bryan O'Donoghue Link: https://lore.kernel.org/r/20240302-linux-next-24-03-01-simple-clock-fixes-v1-1-25f348a5982b@linaro.org Signed-off-by: Stephen Boyd Signed-off-by: zhujun2 --- drivers/clk/clk.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 2e56cc0a3bce..dc5317136eb8 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -414,6 +414,9 @@ static struct clk_core *clk_core_get(struct clk_core *core, u8 p_index) if (IS_ERR(hw)) return ERR_CAST(hw); + if (!hw) + return NULL; + return hw->core; } -- Gitee