From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D3F9B41225; Tue, 28 Jul 2026 01:08:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785200940; cv=none; b=GKuyd92bkYBiXxkozwWeACfKA+g+i7YsudNg3TEV0WRfvqO4sBEf28uGPri3o+gnMTkAQQ+bNl0m1/U3Z0lLEOC8VDz+0/Ntzb7lDzR0P88kgpaj/aZ14RwCqnwfuvkiR1debLmW2lXtcAfPRj5m9EYdoTDuq+8HO/B6awIrkpg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785200940; c=relaxed/simple; bh=wuLHI9PJ37cVbO4KlUcdZsj8x2wzeuv7ucgeTzkebg0=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=cXAgy+jqfQker81qDw9DVk4T72MPb2b5ky++ShWM1Rrpb67S0zqrPLzzifr/ofwaIU/kIrX3ST624lGI75TxsnSZqIq8hhN7meeD5rmCE/xGd1CxNQn/bBi45yplQhrOzkiERyZgdXIfZ+r3uai+M7vNU29BavIpqqpJbH1I4Ic= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Imon9MPQ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Imon9MPQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4EACD1F000E9; Tue, 28 Jul 2026 01:08:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785200935; bh=9zUymOl4IeQd930ZlDC66cwTGV5/HbSV07CpDuG3iEg=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=Imon9MPQVTHFqv4ym3v5EWB9FBff091VMZOyMfAhvrpTS6cTpG25lmv1zbIwlBM1l 43Ga0P4pYugj9SZBnel1WIp98u68lz65Bx+H2YbYS4bI8CLp37NExn9+2SxJFV9G8b xIbsATe/LNbTJxTgg2Az9JI6XblkxKuJ3y0ust11F8jP4iXVtqI1kwsXBV2BPynIBi UeqLbquW2I7k+mHE0CYawaIYkWX6QIVtl9wWq7vjObcft+FANwgBQ4qg9cvb+I4NkQ +IXoa+ZIL+osPnxyTY1/PThWcAzxb/YmSw9HPBEBmKWC5I0BIx6/1TEpmss6SqGjRv V0dv/btO3cjHQ== Date: Mon, 27 Jul 2026 18:08:54 -0700 From: Jakub Kicinski To: David Howells Cc: netdev@vger.kernel.org, Marc Dionne , "David S. Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org, Jeffrey Altman , Jarkko Sakkinen , keyrings@vger.kernel.org, stable@kernel.org Subject: Re: [PATCH net v4 8/9] rxrpc: Fix CHALLENGE packet overqueuing and simplify RESPONSE generation Message-ID: <20260727180854.6280c04b@kernel.org> In-Reply-To: <20260723100309.530157-9-dhowells@redhat.com> References: <20260723100309.530157-1-dhowells@redhat.com> <20260723100309.530157-9-dhowells@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 23 Jul 2026 11:03:04 +0100 David Howells wrote: > Currently, when a CHALLENGE packet comes in, it's queued in an OOB queue on > the AF_RXRPC socket that generated one of the calls on that connection for > the application (which might be in userspace) to service. The application > then picks up the CHALLENGE and requests a RESPONSE packet be generated, > allowing the app to include app-specific data in it if appropriate. There > is, however, no actual limit on the capacity of the CHALLENGE queue, and > this could be abused remotely - and also getting the OOB mechanism right > has proven tricky. net/rxrpc/sendmsg.c:383:37: warning: implicit conversion from 'int' to 'enum rxrpc_abort_reason' changes value from 128 to -128 [-Wconstant-conversion] 383 | trace_rxrpc_abort(call->debug_id, rxrpc_sendmsg_late_send, | ~~~~~~~~~~~~~~~~~ ^~~~~~~~~~~~~~~~~~~~~~~ Sashiko has some comments too (Claude Sashiko didn't run since the code didn't build cleanly). -- pw-bot: cr