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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 78F8BC54E55 for ; Thu, 7 Mar 2024 10:23:33 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1riAt5-0005yt-OV; Thu, 07 Mar 2024 05:22:07 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1riAst-0005af-2M for qemu-devel@nongnu.org; Thu, 07 Mar 2024 05:21:55 -0500 Received: from mail-oi1-x230.google.com ([2607:f8b0:4864:20::230]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1riAsr-0007FU-9i for qemu-devel@nongnu.org; Thu, 07 Mar 2024 05:21:54 -0500 Received: by mail-oi1-x230.google.com with SMTP id 5614622812f47-3c1ea425a0fso269108b6e.3 for ; Thu, 07 Mar 2024 02:21:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=daynix-com.20230601.gappssmtp.com; s=20230601; t=1709806912; x=1710411712; darn=nongnu.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=CotLFv3JVXm6i3Wu/BAcc+rvRVqdPlzG06TuPB40/EU=; b=dcXDxpwZ8sdP9roQ6GExJHSgODK2bFHSmN9sm6P2DvnaLIKTn72yBeTai02WXivKoH iw6oF8Oftf9BAi6QvU7QX9k6IuuvGpNwD5VkQO8WZ2VkMjSUBbiSDyR8/GoDseTuMdfh 6rM19mgjknvH487tRSPQNpFeHpq3a4mKA1l4sfNvwWhFdFjmAaW2X/9QgIGQibszUi4y I92M/28CI5qAJUmf3bgugMlsNOytlgQM9tJwX26lzBFzWVapuY2yZZEfrZ3Jk3RRiJgN Dng06oTE4Yv/Ejoxyp6mvdTzU7nhlgIaG5ioWdxjkAARClu4MSfx1I97xL5sFtvyERMV lEAg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1709806912; x=1710411712; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=CotLFv3JVXm6i3Wu/BAcc+rvRVqdPlzG06TuPB40/EU=; b=F4Qxt9hLH4qIa1iH++uN/E6SW/jqNCc7DDaJSre1lSNiqd+cUj/ud7+e1gJRHwAGXh 4s/zDjlal7avD/1vbZMsjt6Ak1388NqOg5uJe6au3+Rju7ILfHpRyf1U+kL48JkZ7G0q eWu4ORQRjd8J8du2Mt8kfSyccG40RhhXr03VwFb6VuDwzIe/SA3Or4z+UFtkm+afBnMr hSMNlhEZYb6vPpmg4ZqJxr/JSjnwZYMdGXGzzK8UoIlpXJQVX2l9MKZN7KTxkV4F5GGd gDFA3OoBbkMbeHOwzV6AXJ7/RTCyrWhVGfBdqWd7WvZpuQuyLLa4MjaWER9i669vhYpB VWzw== X-Gm-Message-State: AOJu0YzVra74DaU062e0bgqjV/y1aDnlmiXSeKN87bLlKRlVAdUdq/RY Cff8WZLA1blVOzU2yJsWor+bGKfkONbRjC20F0lP7r/zA5L57cThp7BJewQQxAY= X-Google-Smtp-Source: AGHT+IGtJKL80c09SGBnAxxBqv+OCOF4NcVIHEXz2vfqvUZJBiWWkOvD4GEcxOZD0oYjjjrLVel26g== X-Received: by 2002:a05:6808:6297:b0:3c2:154f:7716 with SMTP id du23-20020a056808629700b003c2154f7716mr5593304oib.43.1709806911935; Thu, 07 Mar 2024 02:21:51 -0800 (PST) Received: from localhost ([2400:4050:a840:1e00:9ac7:6d57:2b16:6932]) by smtp.gmail.com with UTF8SMTPSA id z4-20020a626504000000b006e621fd613fsm7032514pfb.80.2024.03.07.02.21.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 07 Mar 2024 02:21:51 -0800 (PST) From: Akihiko Odaki Date: Thu, 07 Mar 2024 19:21:01 +0900 Subject: [PATCH v4 18/19] contrib/elf2dmp: Clamp QEMU note to file size MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20240307-elf2dmp-v4-18-4f324ad4d99d@daynix.com> References: <20240307-elf2dmp-v4-0-4f324ad4d99d@daynix.com> In-Reply-To: <20240307-elf2dmp-v4-0-4f324ad4d99d@daynix.com> To: Viktor Prutyanov , Peter Maydell Cc: qemu-devel@nongnu.org, Akihiko Odaki X-Mailer: b4 0.12.3 Received-SPF: none client-ip=2607:f8b0:4864:20::230; envelope-from=akihiko.odaki@daynix.com; helo=mail-oi1-x230.google.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This fixes crashes with truncated dumps. Signed-off-by: Akihiko Odaki Reviewed-by: Peter Maydell --- contrib/elf2dmp/qemu_elf.c | 87 +++++++++++++++++++++++++++++----------------- 1 file changed, 55 insertions(+), 32 deletions(-) diff --git a/contrib/elf2dmp/qemu_elf.c b/contrib/elf2dmp/qemu_elf.c index 7d896cac5b15..8d750adf904a 100644 --- a/contrib/elf2dmp/qemu_elf.c +++ b/contrib/elf2dmp/qemu_elf.c @@ -6,6 +6,7 @@ */ #include "qemu/osdep.h" +#include "qemu/host-utils.h" #include "err.h" #include "qemu_elf.h" @@ -15,36 +16,11 @@ #define ROUND_UP(n, d) (((n) + (d) - 1) & -(0 ? (n) : (d))) #endif -#ifndef DIV_ROUND_UP -#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) -#endif - -#define ELF_NOTE_SIZE(hdr_size, name_size, desc_size) \ - ((DIV_ROUND_UP((hdr_size), 4) + \ - DIV_ROUND_UP((name_size), 4) + \ - DIV_ROUND_UP((desc_size), 4)) * 4) - int is_system(QEMUCPUState *s) { return s->gs.base >> 63; } -static char *nhdr_get_name(Elf64_Nhdr *nhdr) -{ - return (char *)nhdr + ROUND_UP(sizeof(*nhdr), 4); -} - -static void *nhdr_get_desc(Elf64_Nhdr *nhdr) -{ - return nhdr_get_name(nhdr) + ROUND_UP(nhdr->n_namesz, 4); -} - -static Elf64_Nhdr *nhdr_get_next(Elf64_Nhdr *nhdr) -{ - return (void *)((uint8_t *)nhdr + ELF_NOTE_SIZE(sizeof(*nhdr), - nhdr->n_namesz, nhdr->n_descsz)); -} - Elf64_Phdr *elf64_getphdr(void *map) { Elf64_Ehdr *ehdr = map; @@ -60,13 +36,35 @@ Elf64_Half elf_getphdrnum(void *map) return ehdr->e_phnum; } +static bool advance_note_offset(uint64_t *offsetp, uint64_t size, uint64_t end) +{ + uint64_t offset = *offsetp; + + if (uadd64_overflow(offset, size, &offset) || offset > UINT64_MAX - 3) { + return false; + } + + offset = ROUND_UP(offset, 4); + + if (offset > end) { + return false; + } + + *offsetp = offset; + + return true; +} + static bool init_states(QEMU_Elf *qe) { Elf64_Phdr *phdr = elf64_getphdr(qe->map); - Elf64_Nhdr *start = (void *)((uint8_t *)qe->map + phdr[0].p_offset); - Elf64_Nhdr *end = (void *)((uint8_t *)start + phdr[0].p_memsz); Elf64_Nhdr *nhdr; GPtrArray *states; + QEMUCPUState *state; + uint32_t state_size; + uint64_t offset; + uint64_t end_offset; + char *name; if (phdr[0].p_type != PT_NOTE) { eprintf("Failed to find PT_NOTE\n"); @@ -74,15 +72,40 @@ static bool init_states(QEMU_Elf *qe) } qe->has_kernel_gs_base = 1; + offset = phdr[0].p_offset; states = g_ptr_array_new(); - for (nhdr = start; nhdr < end; nhdr = nhdr_get_next(nhdr)) { - if (!strcmp(nhdr_get_name(nhdr), QEMU_NOTE_NAME)) { - QEMUCPUState *state = nhdr_get_desc(nhdr); + if (uadd64_overflow(offset, phdr[0].p_memsz, &end_offset) || + end_offset > qe->size) { + end_offset = qe->size; + } + + while (offset < end_offset) { + nhdr = (void *)((uint8_t *)qe->map + offset); + + if (!advance_note_offset(&offset, sizeof(*nhdr), end_offset)) { + break; + } + + name = (char *)qe->map + offset; + + if (!advance_note_offset(&offset, nhdr->n_namesz, end_offset)) { + break; + } + + state = (void *)((uint8_t *)qe->map + offset); + + if (!advance_note_offset(&offset, nhdr->n_descsz, end_offset)) { + break; + } + + if (!strcmp(name, QEMU_NOTE_NAME) && + nhdr->n_descsz >= offsetof(QEMUCPUState, kernel_gs_base)) { + state_size = MIN(state->size, nhdr->n_descsz); - if (state->size < sizeof(*state)) { + if (state_size < sizeof(*state)) { eprintf("CPU #%u: QEMU CPU state size %u doesn't match\n", - states->len, state->size); + states->len, state_size); /* * We assume either every QEMU CPU state has KERNEL_GS_BASE or * no one has. -- 2.44.0