From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dy1-f175.google.com (mail-dy1-f175.google.com [74.125.82.175]) (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 9C7E339DBC0 for ; Wed, 13 May 2026 22:33:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.175 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778711630; cv=none; b=O4A/d+PPL4nO960nFT8oO9eRNsG9XCsy3/V2LAiKG+3S5aasShL3dR4cf3w5m4e5D66WpJyOg/RH+udbdPeLWy6liTLBzjPa0xluPmCLktxOQq5cbtx6i5E7H5bf86IBKWRTZ79xu3pZzWk1+Qk0O4uGm0ysChr6Zgp6St9bVvY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778711630; c=relaxed/simple; bh=kgA0KAea695MAc8LHoG5EseKaGFUKSpbXPmYExsdEug=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=auDLabtiX0PcGUq15kf1GpZjQvdylOz12MmCkrcb28IQ3btnyiJJYmdWaD6tGTdkiCbylPjeGPzEYIgLq8WIXsFx5CDqQK2kAr7kErRdgVblrP+w99SSjgotyNbX/gKtYokyXTMnOsKutvKQAMq2csHvDVKs3KLJX5exMcSFtOw= 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=VnHmWezM; arc=none smtp.client-ip=74.125.82.175 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="VnHmWezM" Received: by mail-dy1-f175.google.com with SMTP id 5a478bee46e88-2f03d6cf77bso8369710eec.0 for ; Wed, 13 May 2026 15:33:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1778711628; x=1779316428; darn=vger.kernel.org; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:from:to:cc:subject :date:message-id:reply-to; bh=kgA0KAea695MAc8LHoG5EseKaGFUKSpbXPmYExsdEug=; b=VnHmWezMo0YlbCNcA++RfdlNu1SAfug0zNNW+AX2t6EAp7QeMQCIqBLPh9tYDkgJn/ Ukjlom+POn5HpSnk683AJE96NFrKsWoEOtWmHsQzraB917NphnoaZ4WfEa1S6pQ/jCJY Xu7TMuRJ79epD8mXu+HYjS7UN97TZmYuJYHvbjxNeniFR3pf6GuSDGcuvgfqBypKmW3L EZlQWBd8gtqqFqvbjtD6dd8xsGCG2rMAgqmJAqxfNvdt3Z0ZRHupXQwRdBgQkVX81l0e Cw4KrJS3DEIv7lawH2dowOP0mBVBTS8xR+eRmiHNMMTmUWyY0cGm0t6hUwjm6iI6ur44 LvCQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1778711628; x=1779316428; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=kgA0KAea695MAc8LHoG5EseKaGFUKSpbXPmYExsdEug=; b=Z0t6/DXlVmZiLjUMzXMVd8j0DBhNCjMiZfm1SlQ6n/f2cpZ1+f5jdSLxcJ3CsTahAG U800y1vuZgMgR11oINMMMY2Hy60UmVZlu0s7qU/Xnl7UFao6/GXL5hhiYuOsPZph54In c9ALiPi4jzPIzMEV4Mk+VKes3g0GGspwdU2mWfRJzEJToSzwsl0i+x2rvzfw5LwyR5kG 5Rha8WKorIcLg+aI11u4K1a+jQ4s/Z4sfLcYpzzBAxAz6rPiEb1uU4qGUm58uLMXxu4p OsXyb1tK6BKyAMc8X0UYHf9J9g4Qt1O2080wk1UP9Bkpj094sZlP4QuOEMAW7TW/HT0b fm/A== X-Forwarded-Encrypted: i=1; AFNElJ8TeGYqn69I5ACTD7VXyamWDLnj74FCoLrn71ioGs1F+lFPZ9ugTLf5CdFDBjfkEdYdh6qabptyerZ3n78=@vger.kernel.org X-Gm-Message-State: AOJu0YzqCXT1t2Pubf+d/Jr807HtsFv2L94gSgbTJq4GsnCSKG1F0idw 5pV7kE62c79BcokZeVpHNMBpDbEAg7PIvESRBB3KVQBly/j7DxFuAzpl X-Gm-Gg: Acq92OEcA8rYUmx2aomMeRMUJ9iPj6KAKr1npacWeh8EsbXrZKJoTjBrtNJislyfSUc ygFnOkz9zUsKWhoMvKjN+5C4SA07TpnOKcaeLXJzXjwVNcjFZhPVSidwZF7quCrNIod0ioVoYma /4HjtthAI9aWnbUmNcbRjt7snwsLLb/n7tuphklW/xT3DoF+sSplsDxdKdZLCzs3r9vWk4tFc6b 2dfKMfAJasjrDWNJn3OldY3EQfXmBUjs9vf3Scgd5X0IV8RdjB/JFAkoa9Zcfm9RYFdRnUNdwgQ 3sFZTc7BooL8t8GliHFpHNo6ycN5HKB4FFLPIs4S9woE/mcxTkeV4UDVZg31nprupdEboHSmYDb m8A3YWM8UQUeeJktwt3Xtfj1Hbg7Lym5xlUzquSEesPSNiHO/fL5/dmf7yWmp0XgvmpHuR1mfQd qgOFenwLlj2aDPhNDMiM1Mn1Bjc/9yMdeHuKQAjuNPqkfmxaBs9dM3o990yt4K2y1H9OXuOdQKg r958U0= X-Received: by 2002:a05:7300:c87:b0:2d9:6f2f:9f6f with SMTP id 5a478bee46e88-30119f5955dmr2880656eec.24.1778711627516; Wed, 13 May 2026 15:33:47 -0700 (PDT) Received: from ?IPv6:2a03:83e0:115c:1:5152:641f:f5ef:6c7b? ([2620:10d:c090:500::2:8a9]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-30297bbc9a3sm718642eec.31.2026.05.13.15.33.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 13 May 2026 15:33:47 -0700 (PDT) Message-ID: <2ec40641b6d0313674557a682984d7ea9cdf24a4.camel@gmail.com> Subject: Re: [PATCH RESEND bpf-next v10 4/8] bpf: refactor __bpf_list_add to take insertion point via **prev_ptr From: Eduard Zingerman To: Kaitao cheng , ast@kernel.org, corbet@lwn.net, martin.lau@linux.dev, daniel@iogearbox.net, andrii@kernel.org, song@kernel.org, yonghong.song@linux.dev, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@fomichev.me, haoluo@google.com, jolsa@kernel.org, shuah@kernel.org, chengkaitao@kylinos.cn, skhan@linuxfoundation.org, memxor@gmail.com Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, vmalik@redhat.com, linux-kselftest@vger.kernel.org Date: Wed, 13 May 2026 15:33:44 -0700 In-Reply-To: <20260512055919.95716-5-kaitao.cheng@linux.dev> References: <20260512055919.95716-1-kaitao.cheng@linux.dev> <20260512055919.95716-5-kaitao.cheng@linux.dev> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Tue, 2026-05-12 at 13:59 +0800, Kaitao cheng wrote: > From: Kaitao Cheng >=20 > Refactor __bpf_list_add to accept (node, head, struct list_head **prev_pt= r, > ..) instead of (node, head, bool tail, ..). Load prev from *prev_ptr afte= r > INIT_LIST_HEAD(h), so we never dereference an uninitialized h->prev when > head was 0-initialized (e.g. push_back passes &h->prev). >=20 > When prev is not the list head, validate that prev is in the list via > its owner. >=20 > Prepares for bpf_list_add(head, new, prev, ..) to insert after a given > list node. >=20 > Signed-off-by: Kaitao Cheng > --- Reviewed-by: Eduard Zingerman [...]