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 9C5AC318BA5 for ; Wed, 28 Jan 2026 17:24:37 +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=1769621077; cv=none; b=dQGbQwi/FVSneMbc2Fk0gHg9no3hY+iAQ1bZ/qQ5LRi1TBMxFDzp09hvmDh5bztiiksR4tRueMrqN42QiJX/LHHpT42bRt22SIsVkw9/6gfpCi+vL06q2as6/5DIRiPndNpFMkfYs/pWqEwgQf4svEj1n/Bip42Y5oAGnDDpwHY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769621077; c=relaxed/simple; bh=/2CQfAF62PfgS+QwqoevAqF3YepWLaI2UKaHpfk7vWs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=WrPC58WPwYnbBtMvephiVFVomJkPL1rk/QUo52PrTFtcc5/chEe2uri4qyOEb7B623XWhZlotnko2g/UuUfG1M8BcxLZVmoeK5uQrdYDtGC/ODXPFvlcYmmI3EGrr6ThRSaYOzAzbcKG9bhtWUqJEnj5bGUtqxB9cRVs/IVeGhc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YU4Ecy9f; 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="YU4Ecy9f" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4FF38C116C6; Wed, 28 Jan 2026 17:24:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1769621077; bh=/2CQfAF62PfgS+QwqoevAqF3YepWLaI2UKaHpfk7vWs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=YU4Ecy9fOvN+ELLKMzwDrNvp1vRAf0m7yifJU34cqqEOSWl+4o1p3oOIas1PQJXzB xvJWq6ZPo3ZLmhYCSv/kklsFmWCrkD9KH4qYmQs59aLzJMWKdMZtYAoDYxR3N7YlZj 9tRkXbdOnv8RkZ2ZVkR//yBjorhITvvaTJCg+tR436tATPzJa3hSXhJerjrP18fmkr QdAFBKJnz2Tj5u8MtFXNABt4tdS2IhBwqQJsJ5cBIDf2dJ0ARthAt22XLkECXuRBtS xOzevW6U3gRQSUHYCtaiqkemD6rOASzIABMv7qm2biE+6wi1TolQC1ppBrH76GFvXf OpAkGF8mWtKNw== Date: Wed, 28 Jan 2026 17:24:32 +0000 From: Simon Horman To: Kuniyuki Iwashima Cc: "David S. Miller" , David Ahern , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Kuniyuki Iwashima , netdev@vger.kernel.org, syzbot+d24f940f770afda885cf@syzkaller.appspotmail.com Subject: Re: [PATCH v1 net-next] ipv4: fib: Annotate access to struct fib_alias.fa_state. Message-ID: References: <20260127043528.514160-1-kuniyu@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: <20260127043528.514160-1-kuniyu@google.com> On Tue, Jan 27, 2026 at 04:35:24AM +0000, Kuniyuki Iwashima wrote: > syzbot reported that struct fib_alias.fa_state can be > modified locklessly by RCU readers. [0] > > Let's use READ_ONCE()/WRITE_ONCE() properly. ... > value changed: 0x00 -> 0x01 > > Reported by Kernel Concurrency Sanitizer on: > CPU: 1 UID: 0 PID: 4168 Comm: syz.4.206 Not tainted syzkaller #0 PREEMPT(voluntary) > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 > > Reported-by: syzbot+d24f940f770afda885cf@syzkaller.appspotmail.com > Closes: https://lore.kernel.org/netdev/69783ead.050a0220.c9109.0013.GAE@google.com/ > Signed-off-by: Kuniyuki Iwashima Reviewed-by: Simon Horman