[v2] net: ngbe: fix memory leak in ngbe_probe() error path

[PATCH v2 net] net: ngbe: fix memory leak in ngbe_probe() error path

Posted by Abdun Nihaal 8 months, 1 week ago

When ngbe_sw_init() is called, memory is allocated for wx->rss_key
in wx_init_rss_key(). However, in ngbe_probe() function, the subsequent
error paths after ngbe_sw_init() don't free the rss_key. Fix that by
freeing it in error path along with wx->mac_table.

Also change the label to which execution jumps when ngbe_sw_init()
fails, because otherwise, it could lead to a double free for rss_key,
when the mac_table allocation fails in wx_sw_init().

Fixes: 02338c484ab6 ("net: ngbe: Initialize sw info and register netdev")
Signed-off-by: Abdun Nihaal <abdun.nihaal@gmail.com>
---
v1 -> v2:
- Add fixes tag, as suggested by Markus and Jakub.
- Also set the branch target as net instead of net-next as it is a fix

v1 link: https://lore.kernel.org/all/20250409053804.47855-1-abdun.nihaal@gmail.com

 drivers/net/ethernet/wangxun/ngbe/ngbe_main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
index a6159214ec0a..91b3055a5a9f 100644
--- a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
+++ b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
@@ -625,7 +625,7 @@ static int ngbe_probe(struct pci_dev *pdev,
 	/* setup the private structure */
 	err = ngbe_sw_init(wx);
 	if (err)
-		goto err_free_mac_table;
+		goto err_pci_release_regions;
 
 	/* check if flash load is done after hw power up */
 	err = wx_check_flash_load(wx, NGBE_SPI_ILDR_STATUS_PERST);
@@ -719,6 +719,7 @@ static int ngbe_probe(struct pci_dev *pdev,
 err_clear_interrupt_scheme:
 	wx_clear_interrupt_scheme(wx);
 err_free_mac_table:
+	kfree(wx->rss_key);
 	kfree(wx->mac_table);
 err_pci_release_regions:
 	pci_release_selected_regions(pdev,
-- 
2.47.2

RE: [PATCH v2 net] net: ngbe: fix memory leak in ngbe_probe() error path

Posted by Jiawen Wu 8 months, 1 week ago

On Sat, Apr 12, 2025 11:49 PM, Abdun Nihaal wrote:
> When ngbe_sw_init() is called, memory is allocated for wx->rss_key
> in wx_init_rss_key(). However, in ngbe_probe() function, the subsequent
> error paths after ngbe_sw_init() don't free the rss_key. Fix that by
> freeing it in error path along with wx->mac_table.
> 
> Also change the label to which execution jumps when ngbe_sw_init()
> fails, because otherwise, it could lead to a double free for rss_key,
> when the mac_table allocation fails in wx_sw_init().
> 
> Fixes: 02338c484ab6 ("net: ngbe: Initialize sw info and register netdev")
> Signed-off-by: Abdun Nihaal <abdun.nihaal@gmail.com>
> ---
> v1 -> v2:
> - Add fixes tag, as suggested by Markus and Jakub.
> - Also set the branch target as net instead of net-next as it is a fix
> 
> v1 link: https://lore.kernel.org/all/20250409053804.47855-1-abdun.nihaal@gmail.com
> 
>  drivers/net/ethernet/wangxun/ngbe/ngbe_main.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
> index a6159214ec0a..91b3055a5a9f 100644
> --- a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
> +++ b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
> @@ -625,7 +625,7 @@ static int ngbe_probe(struct pci_dev *pdev,
>  	/* setup the private structure */
>  	err = ngbe_sw_init(wx);
>  	if (err)
> -		goto err_free_mac_table;
> +		goto err_pci_release_regions;
> 
>  	/* check if flash load is done after hw power up */
>  	err = wx_check_flash_load(wx, NGBE_SPI_ILDR_STATUS_PERST);
> @@ -719,6 +719,7 @@ static int ngbe_probe(struct pci_dev *pdev,
>  err_clear_interrupt_scheme:
>  	wx_clear_interrupt_scheme(wx);
>  err_free_mac_table:
> +	kfree(wx->rss_key);
>  	kfree(wx->mac_table);
>  err_pci_release_regions:
>  	pci_release_selected_regions(pdev,
> --
> 2.47.2
> 

Reviewed-by: Jiawen Wu <jiawenwu@trustnetic.com>

Thanks Abdun,
I think this release bug is also present in txgbe driver.

Re: [PATCH v2 net] net: ngbe: fix memory leak in ngbe_probe() error path

Posted by Abdun Nihaal 8 months, 1 week ago

On Tue, Apr 15, 2025 at 10:17:04AM +0800, Jiawen Wu wrote:
> I think this release bug is also present in txgbe driver.

Thanks for the info. I just sent a patch to fix that here : 
https://patchwork.kernel.org/project/netdevbpf/patch/20250415032910.13139-1-abdun.nihaal@gmail.com/

Regards,
Nihaal

Re: [PATCH v2 net] net: ngbe: fix memory leak in ngbe_probe() error path

Posted by Kory Maincent 8 months, 1 week ago

On Sat, 12 Apr 2025 21:19:24 +0530
Abdun Nihaal <abdun.nihaal@gmail.com> wrote:

> When ngbe_sw_init() is called, memory is allocated for wx->rss_key
> in wx_init_rss_key(). However, in ngbe_probe() function, the subsequent
> error paths after ngbe_sw_init() don't free the rss_key. Fix that by
> freeing it in error path along with wx->mac_table.
> 
> Also change the label to which execution jumps when ngbe_sw_init()
> fails, because otherwise, it could lead to a double free for rss_key,
> when the mac_table allocation fails in wx_sw_init().
> 
> Fixes: 02338c484ab6 ("net: ngbe: Initialize sw info and register netdev")
> Signed-off-by: Abdun Nihaal <abdun.nihaal@gmail.com>

legit!

Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>

Thank you!
-- 
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com