From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f182.google.com (mail-pg1-f182.google.com [209.85.215.182]) (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 DFFD82D77EF for ; Fri, 19 Sep 2025 23:09:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758323399; cv=none; b=Z9vafDi4EOZv6aJVaQ04R6e8q4I/ARDx306R6CIEztv64xx/fOuJeoJB3VKArnuRBqFrwMnJ2oXLU5Bi/G3HV4MccUlC0t3D/1bgynk9alyNWjqiBdI9ZmK/20mtFVwZXnV1s7SPLXD0OLdUuo2HZOZ/SGuOSc4F0p0HwE1rqs4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758323399; c=relaxed/simple; bh=pcXardvoZJ5x13AoTWxdTEydJ2BB1/tUU6LaU849Aws=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nmjrKL99K7aTodSeNrr1xlZHUF6Bn2NNh29Ajkvyck2c7iBrWGFa79VXuDLmQxJCFyHTfC52eRfB/ej/8Ue7z+TgBoQJrLRPgZIB8XlpGMZTyqG2C/H57aLmmsLdEpluo2Ua5GIkxa4y8bdVDIJBJnXve43d+ITpduLO548qzjA= 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=WALifacZ; arc=none smtp.client-ip=209.85.215.182 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="WALifacZ" Received: by mail-pg1-f182.google.com with SMTP id 41be03b00d2f7-b54c86f3fdfso2757484a12.1 for ; Fri, 19 Sep 2025 16:09:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1758323397; x=1758928197; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=u/eWmQdzp2gJMKzDrupQRH1sPNWHwWwHav7oa7B7Mo0=; b=WALifacZWN+iIzhBkABObhUV3iG5yV3uX916LFirjENTn5ZY3v9l+40fTxAVpxx14R gGZb8zTVQsRqK8dfCkieG8r7m/tBhYaA3hf2Sd5+A5bI2UKyFHRNBGO9VdWF+A6hGMGv 4hSU1vLR3nbDZyXVo03cBXJlVDaRQevxSyFKN9DJ13BoQCDXx1gwXFu0WlGaEepsOkPX zjZxN3CLwsUkRij5l5ovKvpss6XMmKJ0UIffX+XbhRi1Ce4/6rGgO6kEX9gKg01mCp7z wggdhzV7Uv+N0zkaaFjKlEtWBOb5hNnwgqz7NYds+lsbuxP3DZNDAv2ng/N+7CFpC6Fz 2+jw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758323397; x=1758928197; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=u/eWmQdzp2gJMKzDrupQRH1sPNWHwWwHav7oa7B7Mo0=; b=sFuinoEzteb/ACLQmC13gDNEi1PiajFYFOCDywHWiGH8ekUr6wMQET3OQM8WUT5fiw k6xh+HBz1mn7h9QBkmCtTbmOrqBBfH0KkU43ATtnCsvmOprEEhSh6GZ+Yi1mO//flOhI YFpa0216uisSH9lHsZlLvEuH+Vyg3uRatMoM8S1b/maZDEYgWlmKIKsOvsERjjAYRlFQ WNG0jd0DJQh5wKQBcLGoqoffU3ZNeVsA3RheMOE5Yarsfnk3qsGCIwnJLmz0wPTClsIo ZoExyuwhT+JORm29yi22a0+aKRkvBbKaAx8GJcVk8G3HDJ+U9XCwj/T3C/xEFPJVMHv2 54Qw== X-Gm-Message-State: AOJu0Yy83rkRNWJQNFtX9LWdzc9XzSH8hWa1NEB0fGWHWwIbTMM/Mn+w Ml8d1Yf+T2phNJk5tWVehT9Nl8qY+RlyUBSq5zF3PGN8ejzU4/vBTvBwrYC4XQ== X-Gm-Gg: ASbGncvXViuDlWFZdTiqCeykiYnntqwTXRWOWuCNgNKbp8NM/dtaer5g9Q0IserZlm7 jl+Cbjzdgr5OnUAxqsMbqNTzk1/OAjs3FIrJwIDMrq/Xp0zUAfKggsgfso3otOK5Y5IU3tQOubX IPma1PjnhjmR84ZxRfspyivZpsZxTwHQ/KR5DT82ocfemdTEV5uUyLDJkyufl/b9vyKpheLFN9p WMnPI4xnJ1ntoEBNRBMK4p1WzI+kLi2zYP4D7pT74lN8t/x88Q6AKTbgUyoekwYPoiEpEO9Jx4C VAk3xTEvsv9ygia9mDmYTD+Kst3N26B1+Il6HUfJFYHJhF25rJ0ifKSiiUtjy7DLJatLqbLo2a0 +vWF3I31A0epH X-Google-Smtp-Source: AGHT+IFKBoAz/1ZlBrmFlvmD/RbL1fmSB/1HRKI+iKPRaOGmfLXSkOks6N1F81vSNPT989o7TcuSnA== X-Received: by 2002:a17:90a:db0a:b0:32d:a37c:4e31 with SMTP id 98e67ed59e1d1-3305c70eec4mr9248642a91.17.1758323397052; Fri, 19 Sep 2025 16:09:57 -0700 (PDT) Received: from localhost ([2a03:2880:ff:9::]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-32ed276d2f8sm9348164a91.24.2025.09.19.16.09.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Sep 2025 16:09:56 -0700 (PDT) From: Amery Hung To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, alexei.starovoitov@gmail.com, andrii@kernel.org, daniel@iogearbox.net, paul.chaignon@gmail.com, kuba@kernel.org, stfomichev@gmail.com, martin.lau@kernel.org, mohsin.bashr@gmail.com, noren@nvidia.com, dtatulea@nvidia.com, saeedm@nvidia.com, tariqt@nvidia.com, mbloch@nvidia.com, maciej.fijalkowski@intel.com, kernel-team@meta.com Subject: [PATCH bpf-next v6 4/7] bpf: Clear packet pointers after changing packet data in kfuncs Date: Fri, 19 Sep 2025 16:09:49 -0700 Message-ID: <20250919230952.3628709-5-ameryhung@gmail.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20250919230952.3628709-1-ameryhung@gmail.com> References: <20250919230952.3628709-1-ameryhung@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit bpf_xdp_pull_data() may change packet data and therefore packet pointers need to be invalidated. Add bpf_xdp_pull_data() to the special kfunc list instead of introducing a new KF_ flag until there are more kfuncs changing packet data. Signed-off-by: Amery Hung --- kernel/bpf/verifier.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 1029380f84db..ed493d1dd2e3 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -12239,6 +12239,7 @@ enum special_kfunc_type { KF_bpf_dynptr_from_skb, KF_bpf_dynptr_from_xdp, KF_bpf_dynptr_from_skb_meta, + KF_bpf_xdp_pull_data, KF_bpf_dynptr_slice, KF_bpf_dynptr_slice_rdwr, KF_bpf_dynptr_clone, @@ -12289,10 +12290,12 @@ BTF_ID(func, bpf_rbtree_right) BTF_ID(func, bpf_dynptr_from_skb) BTF_ID(func, bpf_dynptr_from_xdp) BTF_ID(func, bpf_dynptr_from_skb_meta) +BTF_ID(func, bpf_xdp_pull_data) #else BTF_ID_UNUSED BTF_ID_UNUSED BTF_ID_UNUSED +BTF_ID_UNUSED #endif BTF_ID(func, bpf_dynptr_slice) BTF_ID(func, bpf_dynptr_slice_rdwr) @@ -12362,6 +12365,11 @@ static bool is_kfunc_bpf_preempt_enable(struct bpf_kfunc_call_arg_meta *meta) return meta->func_id == special_kfunc_list[KF_bpf_preempt_enable]; } +static bool is_kfunc_pkt_changing(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->func_id == special_kfunc_list[KF_bpf_xdp_pull_data]; +} + static enum kfunc_ptr_arg_type get_kfunc_ptr_arg_type(struct bpf_verifier_env *env, struct bpf_kfunc_call_arg_meta *meta, @@ -14081,6 +14089,9 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, } } + if (is_kfunc_pkt_changing(&meta)) + clear_all_pkt_pointers(env); + nargs = btf_type_vlen(meta.func_proto); args = (const struct btf_param *)(meta.func_proto + 1); for (i = 0; i < nargs; i++) { @@ -17802,6 +17813,8 @@ static int visit_insn(int t, struct bpf_verifier_env *env) */ if (ret == 0 && is_kfunc_sleepable(&meta)) mark_subprog_might_sleep(env, t); + if (ret == 0 && is_kfunc_pkt_changing(&meta)) + mark_subprog_changes_pkt_data(env, t); } return visit_func_call_insn(t, insns, env, insn->src_reg == BPF_PSEUDO_CALL); -- 2.47.3