From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794184125; b=VEfzlmiLOr4R94NxSUbAlRMsBhTA0ZcSKUCVbjhjFxx1GoPVARllrbQzysfTLy2/Ef1m XBGZVlRgVuwVTXLuAr6xwu+Ii5TnrLS22bYbCQtFPxCjj3ZDGdUxCygFxK+5fa/cXmYOn IhlCr4yEJ5Xs4eUVZYh0FajKciIBOZIOfoYBXPHWdqJNb1W3LqqCaTgytbo/49u7jVhKM ccYEiHMyADe6YljhiUB2oPOJxULG+7DZAz4IKihQ7xIHRFIdimq/v5QDY1dUZQGcG3KCa UElSKahf76k/Y3FuLi2XImQbopuZLmnp+AayVN2CEnHzSeRlVZMjgyAsCLdCaAhDYtA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794184125; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=G3Ti5HGbHvQ7VXBzjY8deEsQcMLCkSCpBiVO5wB9ipY=; b=IeuwTK6aqUpSo00eq2MBIuN5sBWlQ0gXtZWO1JUjG+bOyrMdbWxaTlmPWi3/y9XnjnmC WZWPz25qkY3ic8cZqMYJ8nOTxcj+5FwJmguVk7OtoJExXS8qvXNg8TqKEp09zZOOv7PCg +ZS2HPDgVDXAA2lCJZOlM1fWUJXi/q/RUZYeP/gIevSXa8AX76YVDGf/Q2s+a95DQ4URd mqNdd3y4LCRexQPKYpl6yY44j7d5+JcnDRNlTYiQBYdjXKIEhfdCE6XIUZL3n8WMrzWlk RENgnrwQpxs8VbCx8dkKRwNcksmxfpkfoea6WPMLS3hiwuRXutcqQsiNCXEjITndW9A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=FzjhImCP; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AE3D9606A320; Mon, 9 Nov 2026 00:28:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=FzjhImCP Received: by smtp.kernel.org (Postfix) with ESMTPSA id 449111F008A1; Mon, 9 Nov 2026 00:28:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794184124; bh=G3Ti5HGbHvQ7VXBzjY8deEsQcMLCkSCpBiVO5wB9ipY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=FzjhImCPUVVoJ0eVwc6A7YLJ5aaSze2Yva9BCnrANLvVgeOaO3h3znmGzO3okOl1j rz2F/fUkzhq+Pdmw/tHdIhXDd12DgAnrGGz9f/WCpdY3WTqHSW4W2TfFOQVsQZRSVz LYoh57Ea1ttPQ926bOlFi945iRscGfS5seoB6xzZRd+Gx9C6giVcFmzHuzl8aeVo8P qrx/QMfkHjNusKkipJKkTmZsPXgcOalWsTO2dGYXlJ3wdzBsKDeeO35yrV/5Ga/fUd neLL5OvcYmH/MtXb92i0alh2jfy1vtBjeV7JPWmgBFjYAFnbMVnGClxlru1rhCqSdK x/sZAODEgQhsg== From: "Masami Hiramatsu (Google)" To: Steven Rostedt , Masami Hiramatsu Cc: Mathieu Desnoyers , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH 04/12] tracing/probes: Fix missing BTF kind checks in char pointer/array helpers Date: Mon, 9 Nov 2026 09:28:40 +0900 Message-ID: <179418412088.227715.6938451582565786291.stgit@devnote2> X-Mailer: git-send-email 2.43.0 In-Reply-To: <179418408457.227715.1485179201014819821.stgit@devnote2> References: <179418408457.227715.1485179201014819821.stgit@devnote2> User-Agent: StGit/0.19 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit From: Masami Hiramatsu (Google) In struct btf_type, the type ID and byte size share a union, and only BTF_KIND_INT types are followed by a 32-bit integer encoding word. Because btf_type_is_char_ptr() and btf_type_is_char_array() do not verify that the outer type is BTF_KIND_PTR or that the resolved element type is a non-NULL BTF_KIND_INT before inspecting it, non-pointer BTF types can have their byte size misinterpreted as a BTF type ID, and arrays of non-integer types read out-of-bounds or misinterpret trailing BTF metadata as BTF_INT_* encoding bits. Validate the BTF type kinds and NULL pointers before reading inner type metadata in both helpers. Fixes: 27973e5c64b9 ("tracing/probes: Add string type check with BTF") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) --- kernel/trace/trace_probe.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 26e02929f1ff..829fa6559b59 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -411,6 +411,9 @@ static bool btf_type_is_char_ptr(struct btf *btf, const struct btf_type *type) const struct btf_type *real_type; u32 intdata; + if (BTF_INFO_KIND(type->info) != BTF_KIND_PTR) + return false; + real_type = btf_type_skip_modifiers(btf, type->type, NULL); if (!real_type) return false; @@ -435,6 +438,11 @@ static bool btf_type_is_char_array(struct btf *btf, const struct btf_type *type) array = (const struct btf_array *)(type + 1); real_type = btf_type_skip_modifiers(btf, array->type, NULL); + if (!real_type) + return false; + + if (BTF_INFO_KIND(real_type->info) != BTF_KIND_INT) + return false; intdata = btf_type_int(real_type); return !(BTF_INT_ENCODING(intdata) & BTF_INT_SIGNED)