From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E56C12F24; Mon, 23 Jun 2025 13:34:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750685691; cv=none; b=dPtakn728wqpEaqPz5uWiJuJjsXDNRamMNo3+Bfs3/Crvq+bQ6yDLxPApqNcIqbU558z7e7ibQBSr5/h/b7vHzBHcrqGNxRZUSaODAZ6esvde30BWV4D8ohltj/9WzwxQX5kopVwnzMb6A7jFKL6UCgQ+cdC5pVnNNaWJ2S25xc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750685691; c=relaxed/simple; bh=EJqUg7LF5GkDQ49URHUIl9Nz0khY9Ey/bs5YR0Qs7BE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Jx4D9EKbwgUboK9M82PDCjZTVFx01XVfm4JzfKnOMIdlQum5D7b3WOWdwbsnpipTMUVCCTjoBQQMfg2n4XdZTYTnlni1a0mj2sPOjyp6eTRZ4rRIRUY7SRYIDZJsQJlGcsNCQqhzzvYFiVVG+eghdAWUvTQatbYyIT/A9m7WtwY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=sYP9MFXF; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="sYP9MFXF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 21F8AC4CEEA; Mon, 23 Jun 2025 13:34:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1750685690; bh=EJqUg7LF5GkDQ49URHUIl9Nz0khY9Ey/bs5YR0Qs7BE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sYP9MFXFqZcCSKd4TdcUyMpWV3waVPX/mJQHwYOA/vRmoD0Nha3ljBNBQcIcmaK5+ /db0mdvEVaPHTrbKuVkX/EMZJ+1gntZ1iLBNAtEnReGM2ZljWhn9oz/1qTJL1tIE6k KEy2mQnZPKhDzXd0NNiWMbKtqhsd3SIBWtLKiPpQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Anton Protopopov , Andrii Nakryiko , Sasha Levin Subject: [PATCH 5.15 052/411] bpf: Fix uninitialized values in BPF_{CORE,PROBE}_READ Date: Mon, 23 Jun 2025 15:03:16 +0200 Message-ID: <20250623130634.553858290@linuxfoundation.org> X-Mailer: git-send-email 2.50.0 In-Reply-To: <20250623130632.993849527@linuxfoundation.org> References: <20250623130632.993849527@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Anton Protopopov [ Upstream commit 41d4ce6df3f4945341ec509a840cc002a413b6cc ] With the latest LLVM bpf selftests build will fail with the following error message: progs/profiler.inc.h:710:31: error: default initialization of an object of type 'typeof ((parent_task)->real_cred->uid.val)' (aka 'const unsigned int') leaves the object uninitialized and is incompatible with C++ [-Werror,-Wdefault-const-init-unsafe] 710 | proc_exec_data->parent_uid = BPF_CORE_READ(parent_task, real_cred, uid.val); | ^ tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:520:35: note: expanded from macro 'BPF_CORE_READ' 520 | ___type((src), a, ##__VA_ARGS__) __r; \ | ^ This happens because BPF_CORE_READ (and other macro) declare the variable __r using the ___type macro which can inherit const modifier from intermediate types. Fix this by using __typeof_unqual__, when supported. (And when it is not supported, the problem shouldn't appear, as older compilers haven't complained.) Fixes: 792001f4f7aa ("libbpf: Add user-space variants of BPF_CORE_READ() family of macros") Fixes: a4b09a9ef945 ("libbpf: Add non-CO-RE variants of BPF_CORE_READ() macro family") Signed-off-by: Anton Protopopov Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20250502193031.3522715-1-a.s.protopopov@gmail.com Signed-off-by: Sasha Levin --- tools/lib/bpf/bpf_core_read.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/tools/lib/bpf/bpf_core_read.h b/tools/lib/bpf/bpf_core_read.h index b8e68a17f3f1b..442551a501762 100644 --- a/tools/lib/bpf/bpf_core_read.h +++ b/tools/lib/bpf/bpf_core_read.h @@ -272,7 +272,13 @@ enum bpf_enum_value_kind { #define ___arrow10(a, b, c, d, e, f, g, h, i, j) a->b->c->d->e->f->g->h->i->j #define ___arrow(...) ___apply(___arrow, ___narg(__VA_ARGS__))(__VA_ARGS__) +#if defined(__clang__) && (__clang_major__ >= 19) +#define ___type(...) __typeof_unqual__(___arrow(__VA_ARGS__)) +#elif defined(__GNUC__) && (__GNUC__ >= 14) +#define ___type(...) __typeof_unqual__(___arrow(__VA_ARGS__)) +#else #define ___type(...) typeof(___arrow(__VA_ARGS__)) +#endif #define ___read(read_fn, dst, src_type, src, accessor) \ read_fn((void *)(dst), sizeof(*(dst)), &((src_type)(src))->accessor) -- 2.39.5