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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05E02C76191 for ; Mon, 15 Jul 2019 14:16:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C9BA22083D for ; Mon, 15 Jul 2019 14:16:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563200182; bh=tKvy5JbcZXx6YWzfQrPDW5p7WMo9r0DbLOyr2sIo3UE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SVkHSRty24C4BtUkPNM0z6pcpK9swoUQYwmtIjikSkTllw0+g7mB8MLnYgURYfizJ TVqT4WXISLsWqJ+pmL56L/COKpeqfM2u1TIynU8UzY0esUzapOp3eYO8XOA3yjrLkQ vGTOziCApBSAlZG60PfPDk3Iyhrg7ELMuIN+81lU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389702AbfGOOQV (ORCPT ); Mon, 15 Jul 2019 10:16:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:33284 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388662AbfGOOQT (ORCPT ); Mon, 15 Jul 2019 10:16:19 -0400 Received: from sasha-vm.mshome.net (unknown [73.61.17.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 09A6E20651; Mon, 15 Jul 2019 14:16:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563200178; bh=tKvy5JbcZXx6YWzfQrPDW5p7WMo9r0DbLOyr2sIo3UE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t5wPOZV+MM3KRk0kWc7R9qaiW7JJ49vxMibDBfllGG+glGlquUVfQq2n7b8d0Ia9d cW9zYiDLOMZZXTD/VJSWTJuLn2gP4MCkyw0sJQF+ZnZaj42vY7zlUVPcjN+MbdYpVp nmShuIVhbugVLkduwZ0lKnc7YmYdqB1E0EOoOGQo= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jiri Olsa , Michael Petlan , Jiri Olsa , Quentin Monnet , Jakub Kicinski , Daniel Borkmann , Sasha Levin , netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH AUTOSEL 5.1 202/219] tools: bpftool: Fix json dump crash on powerpc Date: Mon, 15 Jul 2019 10:03:23 -0400 Message-Id: <20190715140341.6443-202-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190715140341.6443-1-sashal@kernel.org> References: <20190715140341.6443-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jiri Olsa [ Upstream commit aa52bcbe0e72fac36b1862db08b9c09c4caefae3 ] Michael reported crash with by bpf program in json mode on powerpc: # bpftool prog -p dump jited id 14 [{ "name": "0xd00000000a9aa760", "insns": [{ "pc": "0x0", "operation": "nop", "operands": [null ] },{ "pc": "0x4", "operation": "nop", "operands": [null ] },{ "pc": "0x8", "operation": "mflr", Segmentation fault (core dumped) The code is assuming char pointers in format, which is not always true at least for powerpc. Fixing this by dumping the whole string into buffer based on its format. Please note that libopcodes code does not check return values from fprintf callback, but as per Jakub suggestion returning -1 on allocation failure so we do the best effort to propagate the error. Fixes: 107f041212c1 ("tools: bpftool: add JSON output for `bpftool prog dump jited *` command") Reported-by: Michael Petlan Signed-off-by: Jiri Olsa Reviewed-by: Quentin Monnet Reviewed-by: Jakub Kicinski Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin --- tools/bpf/bpftool/jit_disasm.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/tools/bpf/bpftool/jit_disasm.c b/tools/bpf/bpftool/jit_disasm.c index 3ef3093560ba..bfed711258ce 100644 --- a/tools/bpf/bpftool/jit_disasm.c +++ b/tools/bpf/bpftool/jit_disasm.c @@ -11,6 +11,8 @@ * Licensed under the GNU General Public License, version 2.0 (GPLv2) */ +#define _GNU_SOURCE +#include #include #include #include @@ -44,11 +46,13 @@ static int fprintf_json(void *out, const char *fmt, ...) char *s; va_start(ap, fmt); + if (vasprintf(&s, fmt, ap) < 0) + return -1; + va_end(ap); + if (!oper_count) { int i; - s = va_arg(ap, char *); - /* Strip trailing spaces */ i = strlen(s) - 1; while (s[i] == ' ') @@ -61,11 +65,10 @@ static int fprintf_json(void *out, const char *fmt, ...) } else if (!strcmp(fmt, ",")) { /* Skip */ } else { - s = va_arg(ap, char *); jsonw_string(json_wtr, s); oper_count++; } - va_end(ap); + free(s); return 0; } -- 2.20.1