2020-11-28 22:02:08

by Qinglang Miao

Subject: [PATCH 2/3] powerpc/pseries/hotplug-cpu: fix memleak in dlpar_cpu_add_by_count

kfree(cpu_drcs) should be called when it fails to perform
of_find_node_by_path("/cpus") in dlpar_cpu_add_by_count,
otherwise there would be a memleak.

In fact, the patch a0ff72f9f5a7 ought to remove kfree in
find_dlpar_cpus_to_add rather than dlpar_cpu_add_by_count.
I guess there might be a mistake when apply that one.

Fixes: a0ff72f9f5a7 ("powerpc/pseries/hotplug-cpu: Remove double free in error path")
Reported-by: Hulk Robot <[email protected]>
Signed-off-by: Qinglang Miao <[email protected]>
---
arch/powerpc/platforms/pseries/hotplug-cpu.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index f2837e33b..4bb1c9f2b 100644
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -743,6 +743,7 @@ static int dlpar_cpu_add_by_count(u32 cpus_to_add)
parent = of_find_node_by_path("/cpus");
if (!parent) {
pr_warn("Could not find CPU root node in device tree\n");
+ kfree(cpu_drcs);
return -1;
}

--
2.23.0

2020-11-30 01:55:33

by Michael Ellerman

Subject: Re: [PATCH 2/3] powerpc/pseries/hotplug-cpu: fix memleak in dlpar_cpu_add_by_count

Qinglang Miao <[email protected]> writes:
> kfree(cpu_drcs) should be called when it fails to perform
> of_find_node_by_path("/cpus") in dlpar_cpu_add_by_count,
> otherwise there would be a memleak.
>
> In fact, the patch a0ff72f9f5a7 ought to remove kfree in
> find_dlpar_cpus_to_add rather than dlpar_cpu_add_by_count.
> I guess there might be a mistake when apply that one.
>
> Fixes: a0ff72f9f5a7 ("powerpc/pseries/hotplug-cpu: Remove double free in error path")
> Reported-by: Hulk Robot <[email protected]>
> Signed-off-by: Qinglang Miao <[email protected]>
> ---
> arch/powerpc/platforms/pseries/hotplug-cpu.c | 1 +
> 1 file changed, 1 insertion(+)

This is already fixed in my next by:

a40fdaf1420d ("Revert "powerpc/pseries/hotplug-cpu: Remove double free in error path"")

cheers

> diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
> index f2837e33b..4bb1c9f2b 100644
> --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
> +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
> @@ -743,6 +743,7 @@ static int dlpar_cpu_add_by_count(u32 cpus_to_add)
> parent = of_find_node_by_path("/cpus");
> if (!parent) {
> pr_warn("Could not find CPU root node in device tree\n");
> + kfree(cpu_drcs);
> return -1;
> }
>
> --
> 2.23.0

2020-11-30 07:33:11

by Qinglang Miao

Subject: Re: [PATCH 2/3] powerpc/pseries/hotplug-cpu: fix memleak in dlpar_cpu_add_by_count

?? 2020/11/30 9:51, Michael Ellerman д??:
> Qinglang Miao <[email protected]> writes:
>> kfree(cpu_drcs) should be called when it fails to perform
>> of_find_node_by_path("/cpus") in dlpar_cpu_add_by_count,
>> otherwise there would be a memleak.
>>
>> In fact, the patch a0ff72f9f5a7 ought to remove kfree in
>> find_dlpar_cpus_to_add rather than dlpar_cpu_add_by_count.
>> I guess there might be a mistake when apply that one.
>>
>> Fixes: a0ff72f9f5a7 ("powerpc/pseries/hotplug-cpu: Remove double free in error path")
>> Reported-by: Hulk Robot <[email protected]>
>> Signed-off-by: Qinglang Miao <[email protected]>
>> ---
>> arch/powerpc/platforms/pseries/hotplug-cpu.c | 1 +
>> 1 file changed, 1 insertion(+)
>
> This is already fixed in my next by:
>
> a40fdaf1420d ("Revert "powerpc/pseries/hotplug-cpu: Remove double free in error path"")
>
> cheers'Revert' sounds resonable to this one, glad to know that.
>
>> diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
>> index f2837e33b..4bb1c9f2b 100644
>> --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
>> +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
>> @@ -743,6 +743,7 @@ static int dlpar_cpu_add_by_count(u32 cpus_to_add)
>> parent = of_find_node_by_path("/cpus");
>> if (!parent) {
>> pr_warn("Could not find CPU root node in device tree\n");
>> + kfree(cpu_drcs);
>> return -1;
>> }
>>
>> --
>> 2.23.0
> .
>