From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 7054824215 for ; Fri, 26 Jan 2024 21:25:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706304316; cv=none; b=eBHDyMaC9tcM5nxBuBIV+vNoLJR+EUXL5osmjMPg2SuBFFDSujsyBpN3GGKBTDRkXk9cnhuIH74sORm9yiyVAxElWNKHgnCmIe7YNcDZoEwqK01eFDB27bIZ4rKO45N5kLfT2htVlX/O4ptJbdE68UKFDpjCp+AwjYTlBQBdo+o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706304316; c=relaxed/simple; bh=5frl+3ZsbuHnczYAPFS820f6UJzFarGXvVT9NBTT1jQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=E1rdtAw+sQr5aYfBwxw15neB1QXmtkcNDLJcAkwuhS1Um6SWIm02fCcCpOPwdUfG0C6jle7HL30IFk5d7xzfOD8coR3ZHzq5rR8VNnOVVvHryKnKiSgHdGL6hQsb1w5uJ+cdv38iZ3deOJGodShM3wCGD/Yt8Vvr7rMIrvoP9JI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iGOPHG8Y; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="iGOPHG8Y" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A3F8C433F1; Fri, 26 Jan 2024 21:25:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706304316; bh=5frl+3ZsbuHnczYAPFS820f6UJzFarGXvVT9NBTT1jQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iGOPHG8YhX+/8JMzmOn5vHoG6Y6rz5xLLoQpkyJihSgt7EEmQHcAAQsoRUVUhBntE K53WfobcTZi/2pKm4vubP8oiB8zimATOKJpKDpLcYti1xfV/eGXKCv+QxyNMK6axo+ cm77p7g8C+z8vmlein2L4cJXV/roMssp1RM6Iic9eoIEHw3zEttQybBv8lYlZtaKq6 VnJI380yQT/loXMIptBObpQGLA9CON7pdnRGgJEZFiBmG60sp5v4Rr+L3PTAb18YxP 8+q52Sw5l9ods56eLwvNW1mLFDYoKhBaB8ueyAtGTQkgTDecqLTzaKSzE3J0qFMCy1 MHxZECqL5ho6w== Date: Fri, 26 Jan 2024 21:25:11 +0000 From: Simon Horman To: Eric Dumazet Cc: "David S . Miller" , Jakub Kicinski , Paolo Abeni , David Ahern , netdev@vger.kernel.org, eric.dumazet@gmail.com, syzbot Subject: Re: [PATCH net] ip6_tunnel: make sure to pull inner header in __ip6_tnl_rcv() Message-ID: <20240126212511.GG401354@kernel.org> References: <20240125170557.2663942-1-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240125170557.2663942-1-edumazet@google.com> On Thu, Jan 25, 2024 at 05:05:57PM +0000, Eric Dumazet wrote: > syzbot found __ip6_tnl_rcv() could access unitiliazed data [1]. > > Call pskb_inet_may_pull() to fix this, and initialize ipv6h > variable after this call as it can change skb->head. ... > Fixes: 0d3c703a9d17 ("ipv6: Cleanup IPv6 tunnel receive path") > Reported-by: syzbot > Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman