netdev - Re: [Intel-wired-lan] [PATCH net-next v4 2/2] net/mlx5: Don't use %pK through printk or tracepoints

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <970196ee-9610-453a-aaec-52ffeb3c3115@molgen.mpg.de>
Date: Fri, 18 Jul 2025 15:43:08 +0200
From: Paul Menzel <pmenzel@...gen.mpg.de>
To: Thomas Weißschuh <thomas.weissschuh@...utronix.de>
Cc: Tony Nguyen <anthony.l.nguyen@...el.com>,
 Przemek Kitszel <przemyslaw.kitszel@...el.com>,
 Andrew Lunn <andrew+netdev@...n.ch>, "David S. Miller"
 <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>,
 Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
 Saeed Mahameed <saeedm@...dia.com>, Leon Romanovsky <leon@...nel.org>,
 Tariq Toukan <tariqt@...dia.com>, Mark Bloch <mbloch@...dia.com>,
 intel-wired-lan@...ts.osuosl.org, netdev@...r.kernel.org,
 linux-kernel@...r.kernel.org, linux-rdma@...r.kernel.org,
 Aleksandr Loktionov <aleksandr.loktionov@...el.com>,
 Simon Horman <horms@...nel.org>
Subject: Re: [Intel-wired-lan] [PATCH net-next v4 2/2] net/mlx5: Don't use %pK
 through printk or tracepoints

Dear Thomas,

Thank you for the patch.

Am 18.07.25 um 15:23 schrieb Thomas Weißschuh:
> In the past %pK was preferable to %p as it would not leak raw pointer
> values into the kernel log.
> Since commit ad67b74d2469 ("printk: hash addresses printed with %p")
> the regular %p has been improved to avoid this issue.
> Furthermore, restricted pointers ("%pK") were never meant to be used
> through tracepoints. They can still unintentionally leak raw pointers or
> acquire sleeping locks in atomic contexts.
> 
> Switch to the regular pointer formatting which is safer and
> easier to reason about.
> There are still a few users of %pK left, but these use it through seq_file,
> for which its usage is safe.

The line lengt look a little uneven.

> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@...utronix.de>
> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@...el.com>
> Reviewed-by: Tariq Toukan <tariqt@...dia.com>
> Reviewed-by: Simon Horman <horms@...nel.org>
> ---
>   drivers/net/ethernet/mellanox/mlx5/core/sf/dev/diag/dev_tracepoint.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/diag/dev_tracepoint.h b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/diag/dev_tracepoint.h
> index 0537de86f9817dc80bd897688c539135b1ad37ac..9b0f44253f332aa602a84a1f6d7532a500dd4f55 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/diag/dev_tracepoint.h
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/diag/dev_tracepoint.h
> @@ -28,7 +28,7 @@ DECLARE_EVENT_CLASS(mlx5_sf_dev_template,
>   				   __entry->hw_fn_id = sfdev->fn_id;
>   				   __entry->sfnum = sfdev->sfnum;
>   		    ),
> -		    TP_printk("(%s) sfdev=%pK aux_id=%d hw_id=0x%x sfnum=%u\n",
> +		    TP_printk("(%s) sfdev=%p aux_id=%d hw_id=0x%x sfnum=%u\n",
>   			      __get_str(devname), __entry->sfdev,
>   			      __entry->aux_id, __entry->hw_fn_id,
>   			      __entry->sfnum)
> 

Reviewed-by: Paul Menzel <pmenzel@...gen.mpg.de>

Kind regards,

Paul