bnge: return after auxiliary_device_uninit() in error path

[PATCH net] bnge: return after auxiliary_device_uninit() in error path

Posted by Greg Kroah-Hartman 2 months ago

When auxiliary_device_add() fails, the error block calls
auxiliary_device_uninit() but does not return.  The uninit drops the
last reference and synchronously runs bnge_aux_dev_release(), which sets
bd->auxr_dev = NULL and frees the underlying object.  The subsequent
bd->auxr_dev->net = bd->netdev then dereferences NULL, which is not a
good thing to have happen when trying to clean up from an error.

Add the missing return, as the auxiliary bus documentation states is a
requirement (seems that LLM tools read documentation better than humans
do...)

Cc: Vikas Gupta <vikas.gupta@broadcom.com>
Cc: Andrew Lunn <andrew+netdev@lunn.ch>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Fixes: 8ac050ec3b1c ("bng_en: Add RoCE aux device support")
Cc: stable <stable@kernel.org>
Assisted-by: gregkh_clanker_t1000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/broadcom/bnge/bnge_auxr.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/broadcom/bnge/bnge_auxr.c b/drivers/net/ethernet/broadcom/bnge/bnge_auxr.c
index b942076762ef..67e93e17d4d9 100644
--- a/drivers/net/ethernet/broadcom/bnge/bnge_auxr.c
+++ b/drivers/net/ethernet/broadcom/bnge/bnge_auxr.c
@@ -194,6 +194,7 @@ void bnge_rdma_aux_device_add(struct bnge_dev *bd)
 		dev_warn(bd->dev, "Failed to add auxiliary device for ROCE\n");
 		auxiliary_device_uninit(aux_dev);
 		bd->flags &= ~BNGE_EN_ROCE;
+		return;
 	}
 
 	bd->auxr_dev->net = bd->netdev;
-- 
2.53.0

Re: [PATCH net] bnge: return after auxiliary_device_uninit() in error path

Posted by Vikas Gupta 2 months ago

On Sat, Apr 11, 2026 at 4:15 PM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> When auxiliary_device_add() fails, the error block calls
> auxiliary_device_uninit() but does not return.  The uninit drops the
> last reference and synchronously runs bnge_aux_dev_release(), which sets
> bd->auxr_dev = NULL and frees the underlying object.  The subsequent
> bd->auxr_dev->net = bd->netdev then dereferences NULL, which is not a
> good thing to have happen when trying to clean up from an error.
>
> Add the missing return, as the auxiliary bus documentation states is a
> requirement (seems that LLM tools read documentation better than humans
> do...)
>
> Cc: Vikas Gupta <vikas.gupta@broadcom.com>
> Cc: Andrew Lunn <andrew+netdev@lunn.ch>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Eric Dumazet <edumazet@google.com>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: Paolo Abeni <pabeni@redhat.com>
> Fixes: 8ac050ec3b1c ("bng_en: Add RoCE aux device support")
> Cc: stable <stable@kernel.org>
> Assisted-by: gregkh_clanker_t1000
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

 Reviewed-by: Vikas Gupta <vikas.gupta@broadcom.com>

> ---
>  drivers/net/ethernet/broadcom/bnge/bnge_auxr.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/net/ethernet/broadcom/bnge/bnge_auxr.c b/drivers/net/ethernet/broadcom/bnge/bnge_auxr.c
> index b942076762ef..67e93e17d4d9 100644
> --- a/drivers/net/ethernet/broadcom/bnge/bnge_auxr.c
> +++ b/drivers/net/ethernet/broadcom/bnge/bnge_auxr.c
> @@ -194,6 +194,7 @@ void bnge_rdma_aux_device_add(struct bnge_dev *bd)
>                 dev_warn(bd->dev, "Failed to add auxiliary device for ROCE\n");
>                 auxiliary_device_uninit(aux_dev);
>                 bd->flags &= ~BNGE_EN_ROCE;
> +               return;
>         }
>
>         bd->auxr_dev->net = bd->netdev;
> --
> 2.53.0
>