netdev - Re: [PATCH net] netdev: increment TSO only if TSO is not enabled on any slave device

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

Message-ID: <eae60389-27a5-4e8f-af49-7f75d4c116d8@redhat.com>
Date: Tue, 23 Dec 2025 11:54:57 +0100
From: Paolo Abeni <pabeni@...hat.com>
To: Di Zhu <zhud@...on.cn>, davem@...emloft.net, edumazet@...gle.com,
 kuba@...nel.org, horms@...nel.org, andrew+netdev@...n.ch,
 netdev@...r.kernel.org
Cc: lijing@...on.cn, yingzhiwei@...on.cn
Subject: Re: [PATCH net] netdev: increment TSO only if TSO is not enabled on
 any slave device

On 12/16/25 9:52 AM, Di Zhu wrote:
> Unconditionally increment the TSO flag has a side effect: it will also

This changelog is IMHO quite confusing. The code does not 'increment
TSO'. Instead it increments the features set to include ALL_TSO.

Please reword the changelog accordingly.

> directly clear the flags in NETIF_F_ALL_FOR_ALL on the master device,
> which can cause issues such as the inability to enable the nocache copy
> feature on the bonding network card.

bonding network card -> bonding driver.

> So, when at least one slave device's TSO is enabled, there is no need to
> explicitly increment the TSO flag to the master device.
> 
> Fixes: b0ce3508b25e ("bonding: allow TSO being set on bonding master")
> Signed-off-by: Di Zhu <zhud@...on.cn>
> ---
>  include/linux/netdevice.h | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> index bf99fe8622da..2aca39f7f9e1 100644
> --- a/include/linux/netdevice.h
> +++ b/include/linux/netdevice.h
> @@ -5322,7 +5322,8 @@ netdev_features_t netdev_increment_features(netdev_features_t all,
>  static inline netdev_features_t netdev_add_tso_features(netdev_features_t features,
>  							netdev_features_t mask)
>  {
> -	return netdev_increment_features(features, NETIF_F_ALL_TSO, mask);
> +	return (features & NETIF_F_ALL_TSO) ? features :
> +		netdev_increment_features(features, NETIF_F_ALL_TSO, mask);

NETIF_F_ALL_TSO is not a single bit, but a (later large) bit mask; the
above will yield incorrect result when:

	features & NETIF_F_ALL_TSO != NETIF_F_ALL_TSO

/P