From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oa1-f47.google.com (mail-oa1-f47.google.com [209.85.160.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B26233C3795 for ; Tue, 12 May 2026 16:23:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778603036; cv=none; b=fOVUuAAdqckZexBPQVfMYAL7x2iORnBD8xyDUAeO/ctyDe99zQkP++JqEWX7Mv594rjrL0F2Hiqb6hkvwfNKZWuAqcdVorE3ilf0takAKXwUOgaZyc+d1/DYOg7Gc1EhoLg50/JdphP+sSN15QM8Byx9qo/RM/dcta7G9cCSo2o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778603036; c=relaxed/simple; bh=DpZ2xiYBZM8RQJtYeEHnH+ATTOKfUkIwDCHe3yO+TEg=; h=Mime-Version:Content-Type:Date:Message-Id:From:To:Cc:Subject: References:In-Reply-To; b=qEhgRRyhLq7lL/mJsVOsIJmOP5jIWOJamq59ZOkBHmVOWq53Q9YhtbCKVcCsjXvk8jm46OtsdOITAyvIBCwZGuchKhDRer1/MVq0PVv9WEZBdx/bH6f6ochmxWOmlKBZJGLlOmqdjmhOjXmaSVpM3Se15txtH4p4rnm21TM3NXM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=sJwYR0/S; arc=none smtp.client-ip=209.85.160.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="sJwYR0/S" Received: by mail-oa1-f47.google.com with SMTP id 586e51a60fabf-42c0b0ffac1so3207408fac.2 for ; Tue, 12 May 2026 09:23:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1778603033; x=1779207833; darn=vger.kernel.org; h=in-reply-to:references:subject:cc:to:from:message-id:date :content-transfer-encoding:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=YK365V6RM40TQNol8n1QSn0zSR1IluIGF/pVznNt7N4=; b=sJwYR0/S6l9qWRtmHyqV44PTksuccf/LrGfnnwAuTtSyLLlMb+8t+y6TlMRy03QBYr 3nfPzvTEb+RSISWUBOa0nHlkajhmhQFQiyCNGODrEynYA5HJf//AZHxuftScYGyRswdD PMHLsS500yfqD+a/gaOAtU+TubmiGyOtK6zxvQiWg9WEaGGDO+MwDfTp0Ce5Ok1D8Fhl iRZWSHGmJf0ZrM/E3KliefT2xOTGmZ+QnQ4/PULNjrcfqE7RGFT7gKS7HxcdCQA87yic WrA2Zy4fxT1nT8tAOOSiaDMOsISj/lJb8IrU/LQKIuCQGs+PqQDD6oqjEVm1J4+oV/9f f6jw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1778603033; x=1779207833; h=in-reply-to:references:subject:cc:to:from:message-id:date :content-transfer-encoding:mime-version:x-gm-gg:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=YK365V6RM40TQNol8n1QSn0zSR1IluIGF/pVznNt7N4=; b=LpQGPkOsbWldUM0NY8m1fmXuExswnhf36D4NzIVXGtcq/jXODbJVszdfm1tjWwTLZW T9A/4dskE4PgqDrF06HxCnsoMUczyhF7NCKRg3EvUEDOU0/Ii0HT7cgOwQ98LgjiiSuw sbMUDa7xs/7A24EHmVSCmSEK5OpCEnXHwLXssYEbqYGTfeLhvqgUlWzTFBRi0nsRd4nJ YqDC9UwTkBxu+R0BEKtSu8yqHGVbL4Sx8XxdCc9Rcg9/KFfhH/YEMN68C8Kb1oRCHLNC OYnfH6GtQK/dC9OEioT6NyZflEITyVAZyLHOmDzlbAnpblE86NUzKGIDKsNt/KU12dhs 9OiQ== X-Forwarded-Encrypted: i=1; AFNElJ8AKl8ThllNtPLM+ep9tfXG70FMDVR7eeEk4GKNiyzZVxEiPq1cSQh2b79kPV6zM4olR8I=@vger.kernel.org X-Gm-Message-State: AOJu0YzQ6xUkOlUVdMQs1POm6BHcnUMOplkfB47TLSkoYDt1k4UcHUHy ThMXzQBRxfjAGcixkmKJFA++zohUxnrhe69/z1hW4dHCJ4BuTOSKNA8Z X-Gm-Gg: Acq92OGL+EoOZhoaC88wfm7SaDBAMUpsrq+84NPApxqKcV5Wunv7C6rPxtKCQhloIpn cinDPuOD1FLTzoYKkG/utpe/XyD2HaXJtN0o7yjGC3RU2fmn2DHvvTSDpmNIYUK4WXicRQjQeMr 8kp971NmRoraa81oDlZt6Y05KDAnh31HY1dVNileYvknTV1+U5ejo4Ebs7Ie/ypkYLtMzg+lN1Q jz5sokvopiFCkLABGK4F73JtTkBRe74aKvoqRHYi00zenp5K3rxfNWZhlvcssSawtfsvnBeVvJ/ p5IjWyMpwCPwR1bhKaXD4uk1v6EscJifNQKjcRSiS2mpVFtgrvlbZCC58x8BFJxtF8G6Ki9mhZ5 6hRP3pRZhJPAFpw4mFKKtyYw2FIXo27AOQHfiwRS/KuLbLLaYsISN4yLtf+c8M/wN/c1ltqAM8f zO7HYMuiRFYsfP+ehxerZuQK3tls6KPMXB/b72VFJ8uxxw4fRW6yVcF3p9Z/UCSzAy2rMPjhy1S Ta82EY2qNy8Ro5YatzGPBSmwEFN X-Received: by 2002:a05:6871:8116:b0:42c:d8b:5aad with SMTP id 586e51a60fabf-435892023b9mr8467968fac.33.1778603033383; Tue, 12 May 2026 09:23:53 -0700 (PDT) Received: from localhost ([2a03:2880:10ff:56::]) by smtp.gmail.com with ESMTPSA id 586e51a60fabf-4355710cfccsm13562494fac.8.2026.05.12.09.23.51 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 12 May 2026 09:23:52 -0700 (PDT) Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Tue, 12 May 2026 09:23:51 -0700 Message-Id: From: "Alexei Starovoitov" To: "Yonghong Song" , , Cc: , , , , , , , , Subject: Re: [PATCH bpf-next v3 05/24] bpf: Support stack arguments for bpf functions X-Mailer: aerc References: <20260511053327.1883871-1-yonghong.song@linux.dev> <1bb0dfc54cc2dbe6a38c21af2717f1b575ba60ba66a763952f38ada03a65bf85@mail.kernel.org> <1718e913-d51d-4e81-9106-c39c88e9e160@linux.dev> <5a0b1bdf-951f-4a0c-909a-8c7b0ed8cdc7@linux.dev> In-Reply-To: <5a0b1bdf-951f-4a0c-909a-8c7b0ed8cdc7@linux.dev> On Mon May 11, 2026 at 9:17 PM PDT, Yonghong Song wrote: > > > The insn 12 (r0 =3D *(u64 *)(r11 +8)) is considered safe > and the verification succeeded. > > But this is not correct. The verification should fail due to insn 11. makes sense. > If we add the following in states.c: > > diff --git a/kernel/bpf/states.c b/kernel/bpf/states.c > index 45d86bfe3b68..877338136009 100644 > --- a/kernel/bpf/states.c > +++ b/kernel/bpf/states.c > @@ -941,6 +941,9 @@ static bool func_states_equal(struct bpf_verifier_env= *env, struct bpf_func_stat > if (old->callback_depth > cur->callback_depth) > return false; > =20 > + if (!old->no_stack_arg_load && cur->no_stack_arg_load) > + return false; > + ... > With the above states.c change, old no_stack_arg_load is false and > cur no_stack_arg_load is true, func_states_equal returns false to > allow further for cur verification, which enters insn 12 which will > fail the verification. > > What do you think about the above states.c change? also makes sense to me.