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Date: Thu, 16 Oct 2025 08:38:35 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Fernando Fernandez Mancera <fmancera@suse.de>
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
 gregkh@linuxfoundation.org, cynthia@kosmx.dev, rafael@kernel.org,
 dakr@kernel.org, christian.brauner@ubuntu.com, edumazet@google.com,
 pabeni@redhat.com, davem@davemloft.net, horms@kernel.org
Subject: Re: [PATCH] sysfs: check visibility before changing group attribute
 ownership
Message-ID: <20251016083835.096c09e1@kernel.org>
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On Thu, 16 Oct 2025 12:14:56 +0200 Fernando Fernandez Mancera wrote:
> Since commit 0c17270f9b92 ("net: sysfs: Implement is_visible for
> phys_(port_id, port_name, switch_id)"), __dev_change_net_namespace() can
> hit WARN_ON() when trying to change owner of a file that isn't visible.
> See the trace below:

Dunno much about sysfs but this is what I had in mind so FWIW:

Reviewed-by: Jakub Kicinski <kuba@kernel.org>

I'd be tempted to chuck:

Fixes: 0c17270f9b92 ("net: sysfs: Implement is_visible for phys_(port_id, port_name, switch_id)")

here as well. Or are we certain there are other callers that could have
triggered this earlier?

> Reported-by: Cynthia <cynthia@kosmx.dev>

Perhaps:

Reported-and-bisected-by: ...