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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 9429FC47404 for ; Wed, 9 Oct 2019 03:20:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 687CE206C2 for ; Wed, 9 Oct 2019 03:20:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="o54gf+5a" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730450AbfJIDU2 (ORCPT ); Tue, 8 Oct 2019 23:20:28 -0400 Received: from mail-pg1-f202.google.com ([209.85.215.202]:38339 "EHLO mail-pg1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726490AbfJIDU1 (ORCPT ); Tue, 8 Oct 2019 23:20:27 -0400 Received: by mail-pg1-f202.google.com with SMTP id j7so690080pgj.5 for ; Tue, 08 Oct 2019 20:20:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=//5Om/XvJWZ+udEKS9YxOJkf+X7Db3sKLHkQ/lC+RWM=; b=o54gf+5aWdKfvI+AHUNpNBXeNjtTe200eLPmyr6FlwG3dJE2vLTfRwjsOBV8E1/65K IwO6CN5sWE3V73+pnV123sFvgITRCD26mt+DHCXnWKuj5heDgJDIHnjBAv6AL+z9Py3X 4OMQvnkpWMPCLzbKKyoxRJLLWMrjZ9UjGJCPMyugBqfTDjS0hQ89G7O+474TB+UAA2NZ 3soNbJs2d7npdXHKIhj93Qugh9DEbg7pdjH99OWrgaJY+GGkRDRKfAnWnlZVsmgeMne8 cIDHvfZPbuyO+MhUyOrCSJLwv6MA1yJZXyy9SiyZUsqUPb3/m/srQcmTAYb1/xoSGuPq mytA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=//5Om/XvJWZ+udEKS9YxOJkf+X7Db3sKLHkQ/lC+RWM=; b=WoLlPa3eMwobssbd09ujtQfchI2VqaANBrdVkf385IPFpmv3va41UYbvggkb+rSohg IWZ2CTOsSP2PTQV1Vu6dvxcXLpjULfWNjTMzR+fLG4Oain3bBCFWLUksqtMOJ7xMt76R AFhyNPnn6gaArNKIZbeHATDUgGx0B1FXnRjv3PlRVsFjeVtqXyROv3EWyP9eCpzsTCPv fmx2WdRE1jLbqewWUYdzp6YRpahY62Kj1TEh4+Ui+8LDl9o4aQNGWLv5gbxXllWkJf3i ClijY0g88/cq5razaSrbNsku9uP+m8wnSA2XOLmSM+4qtSYUh9kYvgk0hmO9GzOshw91 Qirg== X-Gm-Message-State: APjAAAXBSisB7qr5jSwp6HYs2OpzkwnizMFQdr2GVOB2q8KWM0Dh6/Cy i6TOb6COXrNltlIYcVkqMjJC/5rOju+BBv5Ms6Y= X-Google-Smtp-Source: APXvYqxX6Bw7jJd8SeEqXgmezuewciPrpKwID/S4IXEyDLLyKeZpW5yRhwJ1SU2B+wrojPsFSueCrn1hxoyFqMenH/o= X-Received: by 2002:a63:495b:: with SMTP id y27mr1959951pgk.438.1570591225171; Tue, 08 Oct 2019 20:20:25 -0700 (PDT) Date: Wed, 9 Oct 2019 11:20:19 +0800 Message-Id: <20191009032019.6954-1-huangrandall@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.23.0.581.g78d2f28ef7-goog Subject: [PATCH] f2fs: fix to avoid memory leakage in f2fs_listxattr From: Randall Huang To: jaegeuk@kernel.org, yuchao0@huawei.com, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Cc: huangrandall@google.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In f2fs_listxattr, there is no boundary check before memcpy e_name to buffer. If the e_name_len is corrupted, unexpected memory contents may be returned to the buffer. Signed-off-by: Randall Huang --- fs/f2fs/xattr.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c index b32c45621679..acc3663970cd 100644 --- a/fs/f2fs/xattr.c +++ b/fs/f2fs/xattr.c @@ -538,8 +538,9 @@ int f2fs_getxattr(struct inode *inode, int index, const char *name, ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) { struct inode *inode = d_inode(dentry); + nid_t xnid = F2FS_I(inode)->i_xattr_nid; struct f2fs_xattr_entry *entry; - void *base_addr; + void *base_addr, *last_base_addr; int error = 0; size_t rest = buffer_size; @@ -549,6 +550,8 @@ ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) if (error) return error; + last_base_addr = (void *)base_addr + XATTR_SIZE(xnid, inode); + list_for_each_xattr(entry, base_addr) { const struct xattr_handler *handler = f2fs_xattr_handler(entry->e_name_index); @@ -559,6 +562,15 @@ ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) if (!handler || (handler->list && !handler->list(dentry))) continue; + if ((void *)(entry) + sizeof(__u32) > last_base_addr || + (void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) { + f2fs_err(F2FS_I_SB(inode), "inode (%lu) has corrupted xattr", + inode->i_ino); + set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK); + error = -EFSCORRUPTED; + goto cleanup; + } + prefix = xattr_prefix(handler); prefix_len = strlen(prefix); size = prefix_len + entry->e_name_len + 1; -- 2.23.0.581.g78d2f28ef7-goog