[PATCH] MIPS: CPC: Fix refcount leak in mips_cpc_default_phys_base

[PATCH] MIPS: CPC: Fix refcount leak in mips_cpc_default_phys_base

[Miaoqian Lin]

of_find_compatible_node() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
Add missing of_node_put() to avoid refcount leak.

Fixes: 791412dafbbf ("MIPS: CPC: Map registers using DT in mips_cpc_default_phys_base()")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
---
 arch/mips/kernel/mips-cpc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/mips/kernel/mips-cpc.c b/arch/mips/kernel/mips-cpc.c
index 17aff13cd7ce..3e386f7e1545 100644
--- a/arch/mips/kernel/mips-cpc.c
+++ b/arch/mips/kernel/mips-cpc.c
@@ -28,6 +28,7 @@ phys_addr_t __weak mips_cpc_default_phys_base(void)
 	cpc_node = of_find_compatible_node(of_root, NULL, "mti,mips-cpc");
 	if (cpc_node) {
 		err = of_address_to_resource(cpc_node, 0, &res);
+		of_node_put(cpc_node);
 		if (!err)
 			return res.start;
 	}
-- 
2.25.1

Re: [PATCH] MIPS: CPC: Fix refcount leak in mips_cpc_default_phys_base

[Thomas Bogendoerfer]

On Mon, May 16, 2022 at 08:33:50AM +0400, Miaoqian Lin wrote:
> of_find_compatible_node() returns a node pointer with refcount
> incremented, we should use of_node_put() on it when done.
> Add missing of_node_put() to avoid refcount leak.
> 
> Fixes: 791412dafbbf ("MIPS: CPC: Map registers using DT in mips_cpc_default_phys_base()")
> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
> ---
>  arch/mips/kernel/mips-cpc.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/mips/kernel/mips-cpc.c b/arch/mips/kernel/mips-cpc.c
> index 17aff13cd7ce..3e386f7e1545 100644
> --- a/arch/mips/kernel/mips-cpc.c
> +++ b/arch/mips/kernel/mips-cpc.c
> @@ -28,6 +28,7 @@ phys_addr_t __weak mips_cpc_default_phys_base(void)
>  	cpc_node = of_find_compatible_node(of_root, NULL, "mti,mips-cpc");
>  	if (cpc_node) {
>  		err = of_address_to_resource(cpc_node, 0, &res);
> +		of_node_put(cpc_node);
>  		if (!err)
>  			return res.start;
>  	}
> -- 
> 2.25.1

this is already fixed in mips-next.

Thomas.

-- 
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea.                                                [ RFC1925, 2.3 ]

Re: [PATCH] MIPS: CPC: Fix refcount leak in mips_cpc_default_phys_base

[Serge Semin]

On Mon, May 16, 2022 at 08:33:50AM +0400, Miaoqian Lin wrote:
> of_find_compatible_node() returns a node pointer with refcount
> incremented, we should use of_node_put() on it when done.
> Add missing of_node_put() to avoid refcount leak.
> 
> Fixes: 791412dafbbf ("MIPS: CPC: Map registers using DT in mips_cpc_default_phys_base()")
> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>

Right. It's similar to the CDMM fix:
commit 4528668ca331 ("mips: cdmm: Fix refcount leak in mips_cdmm_phys_base")

Reviewed-by: Serge Semin <fancer.lancer@gmail.com>

-Sergey

> ---
>  arch/mips/kernel/mips-cpc.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/mips/kernel/mips-cpc.c b/arch/mips/kernel/mips-cpc.c
> index 17aff13cd7ce..3e386f7e1545 100644
> --- a/arch/mips/kernel/mips-cpc.c
> +++ b/arch/mips/kernel/mips-cpc.c
> @@ -28,6 +28,7 @@ phys_addr_t __weak mips_cpc_default_phys_base(void)
>  	cpc_node = of_find_compatible_node(of_root, NULL, "mti,mips-cpc");
>  	if (cpc_node) {
>  		err = of_address_to_resource(cpc_node, 0, &res);
> +		of_node_put(cpc_node);
>  		if (!err)
>  			return res.start;
>  	}
> -- 
> 2.25.1
>