From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792573081; b=ej8brPmgZn+VeprsCqCwRn42BBOMUHZiRykZzdcuuRFGRq8OEGpWlaB2Sb3pvnsT2cvs VKhVZvmtp3yV2ngFComcg7IIehXISJOcNlsDme+3QNzhD5eciJe00kXyF6BSUE2PMvb5H yRKH33oVkmgWpq0rHVj0gWKPyCjgZOFbn/SY5zjrQXVvTRONaxz4/mgJiKQQcIYm2YqyE 2MAJ/dYgAuB4G2BL/P2vLpkHlohdV1WFVv5i1/BTQrCRG8mnPtrbE5oMEF5AyqlXfdV/c u9jTcYoft9vBjTUMdYORRiMxomdonx+/lEtRQG6D4coAgsd4DU2NvRLUHEeRrr6oBTA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792573081; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=PZFsgaUptmthCT9AGjarLBj+dSK/kXdt7D60tO+Fc1E=; b=5lmIdPgbB5l7krq4psi383vPIT7nGQrLsbg7GbQAENq7hRrMroe4OorFoofrQMucQmAH B54yv55MQQ5wEpv9Pnz4D96f6FWcN0Y0FwrZ3Xy2Nb3JA6vqGrSUm6MSRbnxkD3ZPmieA YC2maqAF11PwZcOorCDBtpue4kNr9zOQ96O6/Z+I7JwSTh/jnd0sR6VIGYvJoftxCBqdO lY7nP7pOjVIlCn1PGxRTOjmrpoiTxl5bN5deJumOGi8xfpT+VA/kz8obCiwIHf/UiV5SF FAniABIw1Rm+aFPhvWIsMMlL3TmSlO5TQbF3a1meO7g5rcsIiHe5qOBUjweLa0+AP9w== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="aYmuGmm/"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3D99E606A31B; Wed, 21 Oct 2026 08:58:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=aYmuGmm/ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 939011F000CB; Wed, 21 Oct 2026 08:58:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792573080; bh=PZFsgaUptmthCT9AGjarLBj+dSK/kXdt7D60tO+Fc1E=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=aYmuGmm/+X3TuMt6En/yuxlAevDmd0Bbvy4zAnvkecXFDCBCHH4BFV2HeLMyOncG6 iKGNu8yvxaVvHYNxWEAcOVN5XFBxUULSVRqwdk8C1wabWjN9blXkG2dsAwo0wOz2hT mif8kBJMD1JtRyluN3jtJHEYpowNAAb1jQwIZ/Thfthe/YwWNZrd+u5P5X/YRZJrTI aD3T+PeiWZ6esjBFkbxkPU/x7zC6FMhPE9NGjjuHBE0rmfM1jCQ0Ypf5czE90KkfD7 bfQzKNg7L4JGb9MoBPFM0DJ3BgiIuLatLnXE+esDNPjTCoLkzQ8plSnmclDPAZaIgf TJQiZ5tyQBJzQ== Date: Wed, 21 Oct 2026 10:57:53 +0200 From: Joel Granados To: Oleg Nesterov Cc: Allison Henderson , kernel test robot , oe-lkp@lists.linux.dev, lkp@intel.com, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-s390@vger.kernel.org, linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org, wireguard@lists.zx2c4.com, rds-devel@oss.oracle.com Subject: Re: [linus:master] [sysctl] 8d75c338f0: BUG:KASAN:slab-use-after-free_in_touch_wq_lockdep_map Message-ID: References: <202610190310.9737b2e3-lkp@intel.com> <42964fa071bd8dcafd418c89be6d66856def4dc5.camel@kernel.org> X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="bt355i3q7cyhktpe" Content-Disposition: inline In-Reply-To: --bt355i3q7cyhktpe Content-Type: text/plain; protected-headers=v1; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [linus:master] [sysctl] 8d75c338f0: BUG:KASAN:slab-use-after-free_in_touch_wq_lockdep_map MIME-Version: 1.0 On Tue, Oct 20, 2026 at 01:05:01PM +0200, Oleg Nesterov wrote: > On 10/20, Joel Granados wrote: > > > > On Mon, Oct 19, 2026 at 12:52:58PM -0700, Allison Henderson wrote: > > > > > > CONFIG_SYSCTL=3Dn. A simpler fix might be to just handle the NULL at= the > > > three call sites, e.g.: > > > > > > rds_sysctl_reg_table =3D > > > register_net_sysctl(&init_net, "net/rds", rds_sysctl_= rds_table); > > > if (!rds_sysctl_reg_table && IS_ENABLED(CONFIG_SYSCTL)) > > > return -ENOMEM; > > > > > > > Remember to NULL check rds_sysctl_reg_table in rds_sysctl_exit(). You > > might hit another UAF on exit if you don't. >=20 > Why? unregister_sysctl_table(header) does nothing if header =3D=3D NULL. Nice catch! You can forgo the check as it is the first thing that happens in unregister_sysctl_table. 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