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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=no 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 D9A7FC43603 for ; Thu, 5 Dec 2019 00:52:27 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9C45421823 for ; Thu, 5 Dec 2019 00:52:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="D4nozbjt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9C45421823 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 48ED46B0DC8; Wed, 4 Dec 2019 19:52:27 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 43E026B0DCA; Wed, 4 Dec 2019 19:52:27 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 32DED6B0DCB; Wed, 4 Dec 2019 19:52:27 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0131.hostedemail.com [216.40.44.131]) by kanga.kvack.org (Postfix) with ESMTP id 1D7BD6B0DC8 for ; Wed, 4 Dec 2019 19:52:27 -0500 (EST) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id D8EBC8248D52 for ; Thu, 5 Dec 2019 00:52:26 +0000 (UTC) X-FDA: 76229261892.11.laugh50_1551967767f3e X-HE-Tag: laugh50_1551967767f3e X-Filterd-Recvd-Size: 5093 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf34.hostedemail.com (Postfix) with ESMTP for ; Thu, 5 Dec 2019 00:52:26 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 784B922464; Thu, 5 Dec 2019 00:52:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575507145; bh=r86UrDEAQyyo4Zf0LLWJnHMIISM3OFkMmMyigZFr/P4=; h=Date:From:To:Subject:In-Reply-To:From; b=D4nozbjtXR4AGZPrG/4/jjdzNmJLB33duGu8JH3+8AYS9sqnM9MrHYucXF3JnWP5U 8+apmtGtC7i/+GAlbsgeaN71CL6NcVttztLkFtwlkGqahKp7j0KOOoMzKArQ9Dtuli T4InUR/mtuu04Fs4BHYWbZ5LNF+fONqYpY4zSdwk= Date: Wed, 04 Dec 2019 16:52:25 -0800 From: Andrew Morton To: adobriyan@gmail.com, akpm@linux-foundation.org, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 50/86] fs/binfmt_elf.c: extract elf_read() function Message-ID: <20191205005225.vreagxzGv%akpm@linux-foundation.org> In-Reply-To: <20191204164858.fe4ed8886e34ad9f3b34ea00@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Alexey Dobriyan Subject: fs/binfmt_elf.c: extract elf_read() function ELF reads done by the kernel have very complicated error detection code which better live in one place. Link: http://lkml.kernel.org/r/20191005165215.GB26927@avx2 Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton --- fs/binfmt_elf.c | 49 ++++++++++++++++++++++------------------------ 1 file changed, 24 insertions(+), 25 deletions(-) --- a/fs/binfmt_elf.c~elf-extract-elf_read-function +++ a/fs/binfmt_elf.c @@ -404,6 +404,17 @@ static unsigned long total_mapping_size( ELF_PAGESTART(cmds[first_idx].p_vaddr); } +static int elf_read(struct file *file, void *buf, size_t len, loff_t pos) +{ + ssize_t rv; + + rv = kernel_read(file, buf, len, &pos); + if (unlikely(rv != len)) { + return (rv < 0) ? rv : -EIO; + } + return 0; +} + /** * load_elf_phdrs() - load ELF program headers * @elf_ex: ELF header of the binary whose program headers should be loaded @@ -418,7 +429,6 @@ static struct elf_phdr *load_elf_phdrs(c { struct elf_phdr *elf_phdata = NULL; int retval, err = -1; - loff_t pos = elf_ex->e_phoff; unsigned int size; /* @@ -439,9 +449,9 @@ static struct elf_phdr *load_elf_phdrs(c goto out; /* Read in the program headers */ - retval = kernel_read(elf_file, elf_phdata, size, &pos); - if (retval != size) { - err = (retval < 0) ? retval : -EIO; + retval = elf_read(elf_file, elf_phdata, size, elf_ex->e_phoff); + if (retval < 0) { + err = retval; goto out; } @@ -720,7 +730,6 @@ static int load_elf_binary(struct linux_ elf_ppnt = elf_phdata; for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++) { char *elf_interpreter; - loff_t pos; if (elf_ppnt->p_type != PT_INTERP) continue; @@ -738,14 +747,10 @@ static int load_elf_binary(struct linux_ if (!elf_interpreter) goto out_free_ph; - pos = elf_ppnt->p_offset; - retval = kernel_read(bprm->file, elf_interpreter, - elf_ppnt->p_filesz, &pos); - if (retval != elf_ppnt->p_filesz) { - if (retval >= 0) - retval = -EIO; + retval = elf_read(bprm->file, elf_interpreter, elf_ppnt->p_filesz, + elf_ppnt->p_offset); + if (retval < 0) goto out_free_interp; - } /* make sure path is NULL terminated */ retval = -ENOEXEC; if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0') @@ -764,14 +769,10 @@ static int load_elf_binary(struct linux_ would_dump(bprm, interpreter); /* Get the exec headers */ - pos = 0; - retval = kernel_read(interpreter, &loc->interp_elf_ex, - sizeof(loc->interp_elf_ex), &pos); - if (retval != sizeof(loc->interp_elf_ex)) { - if (retval >= 0) - retval = -EIO; + retval = elf_read(interpreter, &loc->interp_elf_ex, + sizeof(loc->interp_elf_ex), 0); + if (retval < 0) goto out_free_dentry; - } break; @@ -1174,11 +1175,10 @@ static int load_elf_library(struct file unsigned long elf_bss, bss, len; int retval, error, i, j; struct elfhdr elf_ex; - loff_t pos = 0; error = -ENOEXEC; - retval = kernel_read(file, &elf_ex, sizeof(elf_ex), &pos); - if (retval != sizeof(elf_ex)) + retval = elf_read(file, &elf_ex, sizeof(elf_ex), 0); + if (retval < 0) goto out; if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0) @@ -1203,9 +1203,8 @@ static int load_elf_library(struct file eppnt = elf_phdata; error = -ENOEXEC; - pos = elf_ex.e_phoff; - retval = kernel_read(file, eppnt, j, &pos); - if (retval != j) + retval = elf_read(file, eppnt, j, elf_ex.e_phoff); + if (retval < 0) goto out_free_ph; for (j = 0, i = 0; i