[PATCH] Revert "mfd: syscon: Don't free allocated name for regmap_config"

[PATCH] Revert "mfd: syscon: Don't free allocated name for regmap_config"

[Meng.Li]

From: Limeng <Meng.Li@windriver.com>

This reverts commit 529a1101212a785c5df92c314b0e718287150c3b.

The reverted patch moves the memory free to error path, but introduce
a memory leak. There is another commit 94cc89eb8fa5("regmap: debugfs:
Fix handling of name string for debugfs init delays") fixing this
debugfs init issue from root cause. With this fixing, the name field
in struct regmap_debugfs_node is removed. When initialize debugfs
for syscon driver, the name field of struct regmap_config is not
used anymore. So, revert this patch directly to avoid memory leak.

Fixes: 529a1101212a("mfd: syscon: Don't free allocated name for regmap_config")
Cc: stable@vger.kernel.org
Signed-off-by: Meng Li <Meng.Li@windriver.com>
---
 drivers/mfd/syscon.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index ca465794ea9c..df5cebb372a5 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -108,6 +108,7 @@ static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
 	syscon_config.max_register = resource_size(&res) - reg_io_width;
 
 	regmap = regmap_init_mmio(NULL, base, &syscon_config);
+	kfree(syscon_config.name);
 	if (IS_ERR(regmap)) {
 		pr_err("regmap init failed\n");
 		ret = PTR_ERR(regmap);
@@ -144,7 +145,6 @@ static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
 	regmap_exit(regmap);
 err_regmap:
 	iounmap(base);
-	kfree(syscon_config.name);
 err_map:
 	kfree(syscon);
 	return ERR_PTR(ret);
-- 
2.17.1

RE: [PATCH] Revert "mfd: syscon: Don't free allocated name for regmap_config"

[Li, Meng]

Is there any comment on this patch?

Thanks,
Limeng

> -----Original Message-----
> From: Li, Meng <Meng.Li@windriver.com>
> Sent: Monday, December 28, 2020 10:06 AM
> To: linux-kernel@vger.kernel.org
> Cc: lee.jones@linaro.org; arnd@arndb.de; Hao, Kexin
> <Kexin.Hao@windriver.com>; Li, Meng <Meng.Li@windriver.com>
> Subject: [PATCH] Revert "mfd: syscon: Don't free allocated name for
> regmap_config"
> 
> From: Limeng <Meng.Li@windriver.com>
> 
> This reverts commit 529a1101212a785c5df92c314b0e718287150c3b.
> 
> The reverted patch moves the memory free to error path, but introduce a
> memory leak. There is another commit 94cc89eb8fa5("regmap: debugfs:
> Fix handling of name string for debugfs init delays") fixing this debugfs init
> issue from root cause. With this fixing, the name field in struct
> regmap_debugfs_node is removed. When initialize debugfs for syscon driver,
> the name field of struct regmap_config is not used anymore. So, revert this
> patch directly to avoid memory leak.
> 
> Fixes: 529a1101212a("mfd: syscon: Don't free allocated name for
> regmap_config")
> Cc: stable@vger.kernel.org
> Signed-off-by: Meng Li <Meng.Li@windriver.com>
> ---
>  drivers/mfd/syscon.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c index
> ca465794ea9c..df5cebb372a5 100644
> --- a/drivers/mfd/syscon.c
> +++ b/drivers/mfd/syscon.c
> @@ -108,6 +108,7 @@ static struct syscon *of_syscon_register(struct
> device_node *np, bool check_clk)
>  	syscon_config.max_register = resource_size(&res) - reg_io_width;
> 
>  	regmap = regmap_init_mmio(NULL, base, &syscon_config);
> +	kfree(syscon_config.name);
>  	if (IS_ERR(regmap)) {
>  		pr_err("regmap init failed\n");
>  		ret = PTR_ERR(regmap);
> @@ -144,7 +145,6 @@ static struct syscon *of_syscon_register(struct
> device_node *np, bool check_clk)
>  	regmap_exit(regmap);
>  err_regmap:
>  	iounmap(base);
> -	kfree(syscon_config.name);
>  err_map:
>  	kfree(syscon);
>  	return ERR_PTR(ret);
> --
> 2.17.1

Re: [PATCH] Revert "mfd: syscon: Don't free allocated name for regmap_config"

[Lee Jones]

On Mon, 28 Dec 2020, Meng.Li@windriver.com wrote:

> From: Limeng <Meng.Li@windriver.com>
> 
> This reverts commit 529a1101212a785c5df92c314b0e718287150c3b.

But you haven't Cc:ed the author of that commit.

You need to do that, please re-send.

> The reverted patch moves the memory free to error path, but introduce
> a memory leak. There is another commit 94cc89eb8fa5("regmap: debugfs:
> Fix handling of name string for debugfs init delays") fixing this
> debugfs init issue from root cause. With this fixing, the name field
> in struct regmap_debugfs_node is removed. When initialize debugfs
> for syscon driver, the name field of struct regmap_config is not
> used anymore. So, revert this patch directly to avoid memory leak.
> 
> Fixes: 529a1101212a("mfd: syscon: Don't free allocated name for regmap_config")
> Cc: stable@vger.kernel.org
> Signed-off-by: Meng Li <Meng.Li@windriver.com>
> ---
>  drivers/mfd/syscon.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
> index ca465794ea9c..df5cebb372a5 100644
> --- a/drivers/mfd/syscon.c
> +++ b/drivers/mfd/syscon.c
> @@ -108,6 +108,7 @@ static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
>  	syscon_config.max_register = resource_size(&res) - reg_io_width;
>  
>  	regmap = regmap_init_mmio(NULL, base, &syscon_config);
> +	kfree(syscon_config.name);
>  	if (IS_ERR(regmap)) {
>  		pr_err("regmap init failed\n");
>  		ret = PTR_ERR(regmap);
> @@ -144,7 +145,6 @@ static struct syscon *of_syscon_register(struct device_node *np, bool check_clk)
>  	regmap_exit(regmap);
>  err_regmap:
>  	iounmap(base);
> -	kfree(syscon_config.name);
>  err_map:
>  	kfree(syscon);
>  	return ERR_PTR(ret);

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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