All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] fpga: stratix10-soc: fix use-after-free on s10_init()
@ 2019-04-23 23:32 Wen Yang
  2019-04-24  0:21 ` Moritz Fischer
  2019-04-24 11:22 ` Nicolas Saenz Julienne
  0 siblings, 2 replies; 3+ messages in thread
From: Wen Yang @ 2019-04-23 23:32 UTC (permalink / raw)
  To: linux-kernel
  Cc: wang.yi59, Wen Yang, Alan Tull, Moritz Fischer,
	Nicolas Saenz Julienne, linux-fpga

The refcount of fw_np has already been decreased by of_find_matching_node()
so it shouldn't be used anymore.
This patch adds an of_node_get() before of_find_matching_node() to avoid
the use-after-free problem.

Fixes: e7eef1d7633a ("fpga: add intel stratix10 soc fpga manager driver")
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Cc: Alan Tull <atull@kernel.org>
Cc: Moritz Fischer <mdf@kernel.org>
Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Cc: linux-fpga@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/fpga/stratix10-soc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
index 13851b3..215d337 100644
--- a/drivers/fpga/stratix10-soc.c
+++ b/drivers/fpga/stratix10-soc.c
@@ -507,12 +507,16 @@ static int __init s10_init(void)
 	if (!fw_np)
 		return -ENODEV;
 
+	of_node_get(fw_np);
 	np = of_find_matching_node(fw_np, s10_of_match);
-	if (!np)
+	if (!np) {
+		of_node_put(fw_np);
 		return -ENODEV;
+	}
 
 	of_node_put(np);
 	ret = of_platform_populate(fw_np, s10_of_match, NULL, NULL);
+	of_node_put(fw_np);
 	if (ret)
 		return ret;
 
-- 
2.9.5


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] fpga: stratix10-soc: fix use-after-free on s10_init()
  2019-04-23 23:32 [PATCH] fpga: stratix10-soc: fix use-after-free on s10_init() Wen Yang
@ 2019-04-24  0:21 ` Moritz Fischer
  2019-04-24 11:22 ` Nicolas Saenz Julienne
  1 sibling, 0 replies; 3+ messages in thread
From: Moritz Fischer @ 2019-04-24  0:21 UTC (permalink / raw)
  To: Wen Yang
  Cc: linux-kernel, wang.yi59, Alan Tull, Moritz Fischer,
	Nicolas Saenz Julienne, linux-fpga

Hi Wen,

On Wed, Apr 24, 2019 at 07:32:05AM +0800, Wen Yang wrote:
> The refcount of fw_np has already been decreased by of_find_matching_node()
> so it shouldn't be used anymore.
> This patch adds an of_node_get() before of_find_matching_node() to avoid
> the use-after-free problem.
> 
> Fixes: e7eef1d7633a ("fpga: add intel stratix10 soc fpga manager driver")
> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
> Cc: Alan Tull <atull@kernel.org>
> Cc: Moritz Fischer <mdf@kernel.org>
> Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
> Cc: linux-fpga@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org

Reviewed-by: Moritz Fischer <mdf@kernel.org>
> ---
>  drivers/fpga/stratix10-soc.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
> index 13851b3..215d337 100644
> --- a/drivers/fpga/stratix10-soc.c
> +++ b/drivers/fpga/stratix10-soc.c
> @@ -507,12 +507,16 @@ static int __init s10_init(void)
>  	if (!fw_np)
>  		return -ENODEV;
>  
> +	of_node_get(fw_np);
>  	np = of_find_matching_node(fw_np, s10_of_match);
> -	if (!np)
> +	if (!np) {
> +		of_node_put(fw_np);
>  		return -ENODEV;
> +	}
>  
>  	of_node_put(np);
>  	ret = of_platform_populate(fw_np, s10_of_match, NULL, NULL);
> +	of_node_put(fw_np);
>  	if (ret)
>  		return ret;
>  
> -- 
> 2.9.5
> 

Thanks,
Moritz

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] fpga: stratix10-soc: fix use-after-free on s10_init()
  2019-04-23 23:32 [PATCH] fpga: stratix10-soc: fix use-after-free on s10_init() Wen Yang
  2019-04-24  0:21 ` Moritz Fischer
@ 2019-04-24 11:22 ` Nicolas Saenz Julienne
  1 sibling, 0 replies; 3+ messages in thread
From: Nicolas Saenz Julienne @ 2019-04-24 11:22 UTC (permalink / raw)
  To: Wen Yang, linux-kernel; +Cc: wang.yi59, Alan Tull, Moritz Fischer, linux-fpga

[-- Attachment #1: Type: text/plain, Size: 1421 bytes --]

Hi Thanks,

On Wed, 2019-04-24 at 07:32 +0800, Wen Yang wrote:
> The refcount of fw_np has already been decreased by of_find_matching_node()
> so it shouldn't be used anymore.
> This patch adds an of_node_get() before of_find_matching_node() to avoid
> the use-after-free problem.
> 
> Fixes: e7eef1d7633a ("fpga: add intel stratix10 soc fpga manager driver")
> Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
> Cc: Alan Tull <atull@kernel.org>
> Cc: Moritz Fischer <mdf@kernel.org>
> Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
> Cc: linux-fpga@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> ---
>  drivers/fpga/stratix10-soc.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
> index 13851b3..215d337 100644
> --- a/drivers/fpga/stratix10-soc.c
> +++ b/drivers/fpga/stratix10-soc.c
> @@ -507,12 +507,16 @@ static int __init s10_init(void)
>  	if (!fw_np)
>  		return -ENODEV;
>  
> +	of_node_get(fw_np);
>  	np = of_find_matching_node(fw_np, s10_of_match);
> -	if (!np)
> +	if (!np) {
> +		of_node_put(fw_np);
>  		return -ENODEV;
> +	}
>  
>  	of_node_put(np);
>  	ret = of_platform_populate(fw_np, s10_of_match, NULL, NULL);
> +	of_node_put(fw_np);
>  	if (ret)
>  		return ret;
>  


Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>

Regards,
Nicolas


[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2019-04-24 11:22 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-04-23 23:32 [PATCH] fpga: stratix10-soc: fix use-after-free on s10_init() Wen Yang
2019-04-24  0:21 ` Moritz Fischer
2019-04-24 11:22 ` Nicolas Saenz Julienne

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.