[PATCH] clk: tegra: bpmp: Don't crash when a clock fails to register

[PATCH] clk: tegra: bpmp: Don't crash when a clock fails to register

[Mikko Perttunen]

When registering clocks, we just skip any that fail to register
(leaving a NULL hole in the clock table). However, our of_xlate
function still tries to dereference each entry while looking for
the clock with the requested id, causing a crash if any clocks
failed to register. Add a check to of_xlate to skip any NULL
clocks.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
---
 drivers/clk/tegra/clk-bpmp.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/tegra/clk-bpmp.c b/drivers/clk/tegra/clk-bpmp.c
index a896692b74ec..01dada561c10 100644
--- a/drivers/clk/tegra/clk-bpmp.c
+++ b/drivers/clk/tegra/clk-bpmp.c
@@ -586,9 +586,15 @@ static struct clk_hw *tegra_bpmp_clk_of_xlate(struct of_phandle_args *clkspec,
 	unsigned int id = clkspec->args[0], i;
 	struct tegra_bpmp *bpmp = data;
 
-	for (i = 0; i < bpmp->num_clocks; i++)
-		if (bpmp->clocks[i]->id == id)
-			return &bpmp->clocks[i]->hw;
+	for (i = 0; i < bpmp->num_clocks; i++) {
+		struct tegra_bpmp_clk *clk = bpmp->clocks[i];
+
+		if (!clk)
+			continue;
+
+		if (clk->id == id)
+			return &clk->hw;
+	}
 
 	return NULL;
 }
-- 
2.16.1

Re: [PATCH] clk: tegra: bpmp: Don't crash when a clock fails to register

[Jon Hunter]

On 29/06/18 15:38, Mikko Perttunen wrote:
> When registering clocks, we just skip any that fail to register
> (leaving a NULL hole in the clock table). However, our of_xlate
> function still tries to dereference each entry while looking for
> the clock with the requested id, causing a crash if any clocks
> failed to register. Add a check to of_xlate to skip any NULL
> clocks.
> 
> Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
> ---
>  drivers/clk/tegra/clk-bpmp.c | 12 +++++++++---
>  1 file changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/clk/tegra/clk-bpmp.c b/drivers/clk/tegra/clk-bpmp.c
> index a896692b74ec..01dada561c10 100644
> --- a/drivers/clk/tegra/clk-bpmp.c
> +++ b/drivers/clk/tegra/clk-bpmp.c
> @@ -586,9 +586,15 @@ static struct clk_hw *tegra_bpmp_clk_of_xlate(struct of_phandle_args *clkspec,
>  	unsigned int id = clkspec->args[0], i;
>  	struct tegra_bpmp *bpmp = data;
>  
> -	for (i = 0; i < bpmp->num_clocks; i++)
> -		if (bpmp->clocks[i]->id == id)
> -			return &bpmp->clocks[i]->hw;
> +	for (i = 0; i < bpmp->num_clocks; i++) {
> +		struct tegra_bpmp_clk *clk = bpmp->clocks[i];
> +
> +		if (!clk)
> +			continue;
> +
> +		if (clk->id == id)
> +			return &clk->hw;
> +	}
>  
>  	return NULL;
>  }

Acked-by: Jon Hunter <jonathanh@nvidia.com>

Cheers!
Jon

-- 
nvpublic

Re: [PATCH] clk: tegra: bpmp: Don't crash when a clock fails to register

[Stephen Boyd]

Quoting Mikko Perttunen (2018-06-29 07:38:14)
> When registering clocks, we just skip any that fail to register
> (leaving a NULL hole in the clock table). However, our of_xlate
> function still tries to dereference each entry while looking for
> the clock with the requested id, causing a crash if any clocks
> failed to register. Add a check to of_xlate to skip any NULL
> clocks.
> =

> Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
> ---

Applied to clk-next