From mboxrd@z Thu Jan 1 00:00:00 1970 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 476D4C433EF for ; Sat, 7 May 2022 05:26:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1445558AbiEGFaE (ORCPT ); Sat, 7 May 2022 01:30:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55890 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1382363AbiEGF3w (ORCPT ); Sat, 7 May 2022 01:29:52 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 01B2D3B553; Fri, 6 May 2022 22:26:07 -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 8FF8F6009B; Sat, 7 May 2022 05:26:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D8D0DC385A9; Sat, 7 May 2022 05:26:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1651901166; bh=fs8ew1xMDkCcOW8ud/tq/1eNfZxyonp0dSdztdOdG88=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PDawO5UpEZd5zCE2QyOOlrbCFiSnNUQ22QszEz99vcG/g8VRuRDSkr/BXFB5Ih0jo mKfuz9RuB/c+gVwYAHQwm2btrdcp2S1p6jWv4SomDkKHyIdHNAlDkyMkwiOkkG7Tic Z9aKU80c3Y5v7+VihmOz+TTrZevhC6eipj02uQHunTZPmbyAirVATKVFuSDCakemFV koaphLJsubogBkmIba6UYDEksnj0FYw6TRfeGDvOiZGxU15wSsobBAwoFy5+srQNn+ ZLQ9sfC3YifC0Ibqissgsd2ownmpxFjr9crjGm2TrhQTnh3dBsrcYwy8XAlQ5nqwkT q2Xh4VDSdLmhQ== From: Miguel Ojeda To: Linus Torvalds , Greg Kroah-Hartman Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, Jarkko Sakkinen , Miguel Ojeda , Kees Cook , Petr Mladek , Alex Gaynor , Wedson Almeida Filho , Gary Guo , Boqun Feng , Josh Poimboeuf , Jiri Kosina , Miroslav Benes , Joe Lawrence , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , live-patching@vger.kernel.org, linux-perf-users@vger.kernel.org Subject: [PATCH v6 03/23] kallsyms: increase maximum kernel symbol length to 512 Date: Sat, 7 May 2022 07:24:01 +0200 Message-Id: <20220507052451.12890-4-ojeda@kernel.org> In-Reply-To: <20220507052451.12890-1-ojeda@kernel.org> References: <20220507052451.12890-1-ojeda@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Rust symbols can become quite long due to namespacing introduced by modules, types, traits, generics, etc. For instance, the following code: pub mod my_module { pub struct MyType; pub struct MyGenericType(T); pub trait MyTrait { fn my_method() -> u32; } impl MyTrait for MyGenericType { fn my_method() -> u32 { 42 } } } generates a symbol of length 96 when using the upcoming v0 mangling scheme: _RNvXNtCshGpAVYOtgW1_7example9my_moduleINtB2_13MyGenericTypeNtB2_6MyTypeENtB2_7MyTrait9my_method At the moment, Rust symbols may reach up to 300 in length. Setting 512 as the maximum seems like a reasonable choice to keep some headroom. Reviewed-by: Kees Cook Reviewed-by: Petr Mladek Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Co-developed-by: Gary Guo Signed-off-by: Gary Guo Co-developed-by: Boqun Feng Signed-off-by: Boqun Feng Signed-off-by: Miguel Ojeda --- This is a prerequisite patch, independently submitted at: https://lore.kernel.org/lkml/20220506203443.24721-4-ojeda@kernel.org/ include/linux/kallsyms.h | 2 +- kernel/livepatch/core.c | 4 ++-- scripts/kallsyms.c | 4 ++-- tools/include/linux/kallsyms.h | 2 +- tools/lib/perf/include/perf/event.h | 2 +- tools/lib/symbol/kallsyms.h | 2 +- 6 files changed, 8 insertions(+), 8 deletions(-) diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h index ce1bd2fbf23e..e5ad6e31697d 100644 --- a/include/linux/kallsyms.h +++ b/include/linux/kallsyms.h @@ -15,7 +15,7 @@ #include -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 #define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s %s]") + \ (KSYM_NAME_LEN - 1) + \ 2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + \ diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index bc475e62279d..ec06ce59d728 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -213,7 +213,7 @@ static int klp_resolve_symbols(Elf_Shdr *sechdrs, const char *strtab, * we use the smallest/strictest upper bound possible (56, based on * the current definition of MODULE_NAME_LEN) to prevent overflows. */ - BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 128); + BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 512); relas = (Elf_Rela *) relasec->sh_addr; /* For each rela in this klp relocation section */ @@ -227,7 +227,7 @@ static int klp_resolve_symbols(Elf_Shdr *sechdrs, const char *strtab, /* Format: .klp.sym.sym_objname.sym_name,sympos */ cnt = sscanf(strtab + sym->st_name, - ".klp.sym.%55[^.].%127[^,],%lu", + ".klp.sym.%55[^.].%511[^,],%lu", sym_objname, sym_name, &sympos); if (cnt != 3) { pr_err("symbol %s has an incorrectly formatted name\n", diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c index 7e99799aa7b9..275044b840dc 100644 --- a/scripts/kallsyms.c +++ b/scripts/kallsyms.c @@ -30,10 +30,10 @@ #define _stringify_1(x) #x #define _stringify(x) _stringify_1(x) -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 /* A substantially bigger size than the current maximum. */ -#define KSYM_NAME_LEN_BUFFER 512 +#define KSYM_NAME_LEN_BUFFER 2048 _Static_assert( KSYM_NAME_LEN_BUFFER == KSYM_NAME_LEN * 4, "Please keep KSYM_NAME_LEN_BUFFER in sync with KSYM_NAME_LEN" diff --git a/tools/include/linux/kallsyms.h b/tools/include/linux/kallsyms.h index efb6c3f5f2a9..5a37ccbec54f 100644 --- a/tools/include/linux/kallsyms.h +++ b/tools/include/linux/kallsyms.h @@ -6,7 +6,7 @@ #include #include -#define KSYM_NAME_LEN 128 +#define KSYM_NAME_LEN 512 struct module; diff --git a/tools/lib/perf/include/perf/event.h b/tools/lib/perf/include/perf/event.h index e7758707cadd..116a80c31675 100644 --- a/tools/lib/perf/include/perf/event.h +++ b/tools/lib/perf/include/perf/event.h @@ -95,7 +95,7 @@ struct perf_record_throttle { }; #ifndef KSYM_NAME_LEN -#define KSYM_NAME_LEN 256 +#define KSYM_NAME_LEN 512 #endif struct perf_record_ksymbol { diff --git a/tools/lib/symbol/kallsyms.h b/tools/lib/symbol/kallsyms.h index 72ab9870454b..542f9b059c3b 100644 --- a/tools/lib/symbol/kallsyms.h +++ b/tools/lib/symbol/kallsyms.h @@ -7,7 +7,7 @@ #include #ifndef KSYM_NAME_LEN -#define KSYM_NAME_LEN 256 +#define KSYM_NAME_LEN 512 #endif static inline u8 kallsyms2elf_binding(char type) -- 2.35.3