From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-00206402.pphosted.com (mx0a-00206402.pphosted.com [148.163.148.77]) (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 E8AA925B30D; Mon, 23 Feb 2026 08:32:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.148.77 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771835546; cv=none; b=Smqd5DxZbBAsxTpeuZ5oZLsRrNkhAbZCpM/Emzb5yV+rKMsYDT9cATWA93OtY6NLqK2efwkkS3C9sGf0xSL8HG+cB6OUGPpNghdsdcpfmG+dpxJWgNz3w0L3RZO2+Ky3h55irC5+eq9XqAJtB+VmdqM965dPOd0EhW6vuUjrfWo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771835546; c=relaxed/simple; bh=4ieYK3cRf1tZwlyQChJjd4gD7zfKRU8fr8eKjJ9PXgQ=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=asLxm+p1GyVeEUmo9S0bLAb6pIMjxhGQcW3SQJyIo1PyIgE1eNzUIYbScjNHiVcHYI6dk9mjhY/xp0LOJ7zOGErmx3tVwxji1aTCkMZWpchbqJzZqduBdmoc9Rey9OmpShISGKyWWh2SeyCOvZXWASgaGKcpD2rAaO1erQX0mTE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=crowdstrike.com; spf=pass smtp.mailfrom=crowdstrike.com; dkim=pass (2048-bit key) header.d=crowdstrike.com header.i=@crowdstrike.com header.b=E9tEI4Yd; arc=none smtp.client-ip=148.163.148.77 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=crowdstrike.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=crowdstrike.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=crowdstrike.com header.i=@crowdstrike.com header.b="E9tEI4Yd" Received: from pps.filterd (m0354650.ppops.net [127.0.0.1]) by mx0a-00206402.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 61N8KlEj878227; Mon, 23 Feb 2026 08:31:43 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crowdstrike.com; h=cc:content-transfer-encoding:content-type:date:from :in-reply-to:message-id:mime-version:references:subject:to; s= default; bh=vYx/jH9GitWnsBNFZ6gIWwT1tUF7qtMtnlpm5bKI1ao=; b=E9tE I4YdMdgamm6S1NJDj0eH2ZTux/AOLa/uLDWIIJzakq5zncTd+WAfXJDhHCYH+/g6 +ndvWTS0L9YSqypWyxp1PgXXpizgh4Kj0v3TPb8GGAr7EyaPLuKXDAFINmzQaFPj e3lPB1XvmzDAfh92GQNHYg8rWr+gwgvWGWC+oBZhLDbSftouqYXoCvwre83JBG8k tvG3eoDX2EAFn7p9JuL6QrzDLzoY2tC0hUUsViAfmm/xVOe52FGPgUq4Jhc//Nzl +r+EV50xKCcaS/91ttxnfd2/b2ZMgGxdYJs2mAVUEL8hZhFVTJY3h2goMJH2vJjX D0dT7pE7kd1YOuhcAw== Received: from mail.crowdstrike.com (dragosx.crowdstrike.com [208.42.231.60] (may be forged)) by mx0a-00206402.pphosted.com (PPS) with ESMTPS id 4cfs69uq9b-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 23 Feb 2026 08:31:43 +0000 (GMT) Received: from ML-CTVHTF21DX.crowdstrike.sys (10.100.11.122) by 04WPEXCH006.crowdstrike.sys (10.100.11.70) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.35; Mon, 23 Feb 2026 08:31:37 +0000 From: Slava Imameev To: , , CC: , , , , , , , , , , , , , , , , , , , , Slava Imameev Subject: [PATCH bpf-next v3 1/2] bpf: Support multi-level pointer params via SCALAR_VALUE for trampolines Date: Mon, 23 Feb 2026 19:31:19 +1100 Message-ID: <20260223083120.23776-2-slava.imameev@crowdstrike.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20260223083120.23776-1-slava.imameev@crowdstrike.com> References: <20260223083120.23776-1-slava.imameev@crowdstrike.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: 04WPEXCH005.crowdstrike.sys (10.100.11.69) To 04WPEXCH006.crowdstrike.sys (10.100.11.70) X-Disclaimer: USA X-Proofpoint-GUID: NkhjyTNwDmIHDp7QeUP4Lx0iCQt85Vfx X-Authority-Analysis: v=2.4 cv=COInnBrD c=1 sm=1 tr=0 ts=699c106f cx=c_pps a=1d8vc5iZWYKGYgMGCdbIRA==:117 a=1d8vc5iZWYKGYgMGCdbIRA==:17 a=EjBHVkixTFsA:10 a=HzLeVaNsDn8A:10 a=VkNPw1HP01LnGYTKEx00:22 a=T2KQ53IYiC3MXPrxx8bB:22 a=t04HzT_fAfAF5W-3wVZy:22 a=pl6vuDidAAAA:8 a=XeiW-fLPYlId-uVOQeEA:9 X-Proofpoint-ORIG-GUID: NkhjyTNwDmIHDp7QeUP4Lx0iCQt85Vfx X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMjIzMDA3NSBTYWx0ZWRfX5+S+U54PN+KX 0N6UXL7F6CXHAhyff63vBySjDi4f6aWtZGcIu4ybTY6RCjV1PocOKjSz9XKDe1wfyU2WsSw+xwv VA8NQzpIzmW9u8jq0HgEAbCpTwfsp/s1VTaNTRQXbM6vApd4G5+jlAeSwxTfDRk0CWkoMZCGztd XtZjA9AYYdi/FxXM3HYWU/HBnl3vIamVT8rztZiI6N/C2LfLddE9tKX+2LhPQEj9+urnP6yGTjm kDiXAnIDc2CaXz2RlZwuubfTxtgLgn6AFKfF1kdiACLxkRik1gm//eVmFsrNLppZqlm/ZjCq6IX ca1cvgupou5UbP9vHWNJ2lgUH3TMD+4Kv87eTNKe2SfFpwpw5lmuz1+YAd7iwTSSWbEYMNFHMJ0 5U1o6eDro+GB251lF1vmmdKd95lG3JrrDKHZthm77KU6rTwVm0AhCtYgkL4h6AOjLwThJHMdo4w UixnucLSgRW1yUM8lAw== X-Proofpoint-Virus-Version: vendor=nai engine=6800 definitions=11709 signatures=596818 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 bulkscore=0 lowpriorityscore=0 phishscore=0 priorityscore=1501 adultscore=0 spamscore=0 suspectscore=0 impostorscore=0 malwarescore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2602130000 definitions=main-2602230075 Add BPF verifier support for multi-level pointer parameters and return values in BPF trampolines. The implementation treats these parameters as SCALAR_VALUE. Signed-off-by: Slava Imameev --- kernel/bpf/btf.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 7708958e3fb8..ebb1b0c3f993 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -760,6 +760,21 @@ const struct btf_type *btf_type_resolve_func_ptr(const struct btf *btf, return NULL; } +static bool is_multilevel_ptr(const struct btf *btf, const struct btf_type *t) +{ + u32 depth = 0; + + if (!btf_type_is_ptr(t)) + return false; + + do { + depth += 1; + t = btf_type_skip_modifiers(btf, t->type, NULL); + } while (btf_type_is_ptr(t) && depth < 2); + + return depth > 1; +} + /* Types that act only as a source, not sink or intermediate * type when resolving. */ @@ -6905,8 +6920,11 @@ bool btf_ctx_access(int off, int size, enum bpf_access_type type, /* * If it's a pointer to void, it's the same as scalar from the verifier * safety POV. Either way, no futher pointer walking is allowed. + * Multilevel pointers (e.g., int**, struct foo**, char***) of any type + * are treated as scalars because the verifier lacks the context to infer + * the size of their target memory regions. */ - if (is_void_or_int_ptr(btf, t)) + if (is_void_or_int_ptr(btf, t) || is_multilevel_ptr(btf, t)) return true; /* this is a pointer to another type */ -- 2.34.1