From nobody Wed Sep 3 06:45:17 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5EA7EC38A2D for ; Mon, 24 Oct 2022 12:22:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233529AbiJXMWp (ORCPT ); Mon, 24 Oct 2022 08:22:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233242AbiJXMUT (ORCPT ); Mon, 24 Oct 2022 08:20:19 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C91E7C1AD; Mon, 24 Oct 2022 04:59:02 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A468A612C5; Mon, 24 Oct 2022 11:58:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B5CAAC433D6; Mon, 24 Oct 2022 11:58:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666612685; bh=mjCwChMoj0gYfMSKB/1bs/M2Mqi6HjkqAeGsiTHVQ1k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PXVcrBkg3n+V3dfWIyv7JHmlwjjuKH37UFD9s9DuulHuqay6Zdn73E3b3eX8BG/8U XtJ0YE+Wi8QIXdLx1Gah1k2CU9Ek53YAxMIRE/o8t7R8q6EvbSFMOE2VtIp0RhlYSM sM0D1f/SmTLnSHqJ+DGXvTbGlujEQOhWuRmxxpQE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stanislav Fomichev , Lorenz Bauer , Alexei Starovoitov , Sasha Levin Subject: [PATCH 4.19 079/229] bpf: btf: fix truncated last_member_type_id in btf_struct_resolve Date: Mon, 24 Oct 2022 13:29:58 +0200 Message-Id: <20221024113001.628698887@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024112959.085534368@linuxfoundation.org> References: <20221024112959.085534368@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Lorenz Bauer [ Upstream commit a37a32583e282d8d815e22add29bc1e91e19951a ] When trying to finish resolving a struct member, btf_struct_resolve saves the member type id in a u16 temporary variable. This truncates the 32 bit type id value if it exceeds UINT16_MAX. As a result, structs that have members with type ids > UINT16_MAX and which need resolution will fail with a message like this: [67414] STRUCT ff_device size=3D120 vlen=3D12 effect_owners type_id=3D67434 bits_offset=3D960 Member exceeds stru= ct_size Fix this by changing the type of last_member_type_id to u32. Fixes: a0791f0df7d2 ("bpf: fix BTF limits") Reviewed-by: Stanislav Fomichev Signed-off-by: Lorenz Bauer Link: https://lore.kernel.org/r/20220910110120.339242-1-oss@lmb.io Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- kernel/bpf/btf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 471cc5c117a5..62e05b6283c0 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -1660,7 +1660,7 @@ static int btf_struct_resolve(struct btf_verifier_env= *env, if (v->next_member) { const struct btf_type *last_member_type; const struct btf_member *last_member; - u16 last_member_type_id; + u32 last_member_type_id; =20 last_member =3D btf_type_member(v->t) + v->next_member - 1; last_member_type_id =3D last_member->type; --=20 2.35.1