From patchwork Fri Oct 2 17:38:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11814221 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4A635618 for ; Fri, 2 Oct 2020 17:38:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 277B42085B for ; Fri, 2 Oct 2020 17:38:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="dhTPr3Hf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388385AbgJBRij (ORCPT ); Fri, 2 Oct 2020 13:38:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55782 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388375AbgJBRii (ORCPT ); Fri, 2 Oct 2020 13:38:38 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A43B0C0613E7 for ; Fri, 2 Oct 2020 10:38:38 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id x22so1729276pfo.12 for ; Fri, 02 Oct 2020 10:38:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=lZhM0u1Ixh6Kh+HXvNSm8TOvqXs6GWG/DhLCwiIZPAQ=; b=dhTPr3HfrcE87niKjHnrsTeF1TcXrwE3MtOzEVE6zgIgOvNW2rTQI9z3LOdcFoyVDM SBGNwTYXUuqJM/f0GmpP0X0+JEVgSuETIXvn6XfOmQ/TeXGBd3DyqhtRg4DFLO1+L2Mr i558wv0fKdwpBIUsFJJ9VnuXXiUIkFoFIk9vk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=lZhM0u1Ixh6Kh+HXvNSm8TOvqXs6GWG/DhLCwiIZPAQ=; b=Lo2jeXYDiU37yrbBwC8ptLMRMJW0n5EbYYeIFPzwjV8xLSxk1HT4HRvmtiNI/bPlLP KV+xFDRfa+Zpg7aZke1tBxyaEW4edttSciR3OTbQMZNk3tUUM7HPFlsL1frNjL22XgFu DoBtYrWlvpqf2487BeLVLK6KyAYpTyYPtlVHvaaip5VWTXt4qxvPVO2dBXYOeEk1tgRn uPKC7pIH6g/Zwj82TyldnjCv/Ttzj2YumaBX8Q6XPiuzQtm7qLB2kcgpsllvr2iN2lic 409GbM5mIFwD5OwCcKIgu88eAFq/qeUdtdgebbfzPOezkyrgfJ0FvBSd9heyLp9fntf1 AOsg== X-Gm-Message-State: AOAM530izLLn25GaCfj2llEgYnrEa1AsuJixp5EIeP3BDM/Zg+wN3Sjd LJ0pfPv1ON9KHtFDJcf2IqXDDw== X-Google-Smtp-Source: ABdhPJwaD4NElc+GQ4IINbv7oc2YCpYC1zsjIXxVz9EyAd0B1Cyyi5Hk2RJaUftxrf7tj37r6wGe1A== X-Received: by 2002:a62:3382:0:b029:150:bde9:d408 with SMTP id z124-20020a6233820000b0290150bde9d408mr4200055pfz.12.1601660318157; Fri, 02 Oct 2020 10:38:38 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id l10sm2157310pgp.25.2020.10.02.10.38.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 02 Oct 2020 10:38:36 -0700 (PDT) From: Kees Cook To: Greg Kroah-Hartman Cc: Kees Cook , Mimi Zohar , Luis Chamberlain , James Morris , Scott Branden , Takashi Iwai , Jessica Yu , SeongJae Park , KP Singh , linux-efi@vger.kernel.org, linux-security-module@vger.kernel.org, linux-integrity@vger.kernel.org, selinux@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 05/16] fs/kernel_read_file: Remove redundant size argument Date: Fri, 2 Oct 2020 10:38:17 -0700 Message-Id: <20201002173828.2099543-6-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201002173828.2099543-1-keescook@chromium.org> References: <20201002173828.2099543-1-keescook@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org In preparation for refactoring kernel_read_file*(), remove the redundant "size" argument which is not needed: it can be included in the return code, with callers adjusted. (VFS reads already cannot be larger than INT_MAX.) Signed-off-by: Kees Cook Reviewed-by: Mimi Zohar Reviewed-by: Luis Chamberlain Reviewed-by: James Morris Acked-by: Scott Branden --- drivers/base/firmware_loader/main.c | 10 ++++++---- fs/kernel_read_file.c | 20 +++++++++----------- include/linux/kernel_read_file.h | 8 ++++---- kernel/kexec_file.c | 14 +++++++------- kernel/module.c | 7 +++---- security/integrity/digsig.c | 5 +++-- security/integrity/ima/ima_fs.c | 6 ++++-- 7 files changed, 36 insertions(+), 34 deletions(-) diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 8c6ea389afcf..6df1bdcfeb9d 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -467,7 +467,7 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, size_t in_size, const void *in_buffer)) { - loff_t size; + size_t size; int i, len; int rc = -ENOENT; char *path; @@ -499,10 +499,9 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, fw_priv->size = 0; /* load firmware files from the mount namespace of init */ - rc = kernel_read_file_from_path_initns(path, &buffer, - &size, msize, + rc = kernel_read_file_from_path_initns(path, &buffer, msize, READING_FIRMWARE); - if (rc) { + if (rc < 0) { if (rc != -ENOENT) dev_warn(device, "loading %s failed with error %d\n", path, rc); @@ -511,6 +510,9 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, path); continue; } + size = rc; + rc = 0; + dev_dbg(device, "Loading firmware from %s\n", path); if (decompress) { dev_dbg(device, "f/w decompressing %s\n", diff --git a/fs/kernel_read_file.c b/fs/kernel_read_file.c index 54d972d4befc..dc28a8def597 100644 --- a/fs/kernel_read_file.c +++ b/fs/kernel_read_file.c @@ -5,7 +5,7 @@ #include #include -int kernel_read_file(struct file *file, void **buf, loff_t *size, +int kernel_read_file(struct file *file, void **buf, loff_t max_size, enum kernel_read_file_id id) { loff_t i_size, pos; @@ -29,7 +29,7 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size, ret = -EINVAL; goto out; } - if (i_size > SIZE_MAX || (max_size > 0 && i_size > max_size)) { + if (i_size > INT_MAX || (max_size > 0 && i_size > max_size)) { ret = -EFBIG; goto out; } @@ -59,8 +59,6 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size, } ret = security_kernel_post_read_file(file, *buf, i_size, id); - if (!ret) - *size = pos; out_free: if (ret < 0) { @@ -72,11 +70,11 @@ int kernel_read_file(struct file *file, void **buf, loff_t *size, out: allow_write_access(file); - return ret; + return ret == 0 ? pos : ret; } EXPORT_SYMBOL_GPL(kernel_read_file); -int kernel_read_file_from_path(const char *path, void **buf, loff_t *size, +int kernel_read_file_from_path(const char *path, void **buf, loff_t max_size, enum kernel_read_file_id id) { struct file *file; @@ -89,14 +87,14 @@ int kernel_read_file_from_path(const char *path, void **buf, loff_t *size, if (IS_ERR(file)) return PTR_ERR(file); - ret = kernel_read_file(file, buf, size, max_size, id); + ret = kernel_read_file(file, buf, max_size, id); fput(file); return ret; } EXPORT_SYMBOL_GPL(kernel_read_file_from_path); int kernel_read_file_from_path_initns(const char *path, void **buf, - loff_t *size, loff_t max_size, + loff_t max_size, enum kernel_read_file_id id) { struct file *file; @@ -115,13 +113,13 @@ int kernel_read_file_from_path_initns(const char *path, void **buf, if (IS_ERR(file)) return PTR_ERR(file); - ret = kernel_read_file(file, buf, size, max_size, id); + ret = kernel_read_file(file, buf, max_size, id); fput(file); return ret; } EXPORT_SYMBOL_GPL(kernel_read_file_from_path_initns); -int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size, +int kernel_read_file_from_fd(int fd, void **buf, loff_t max_size, enum kernel_read_file_id id) { struct fd f = fdget(fd); @@ -130,7 +128,7 @@ int kernel_read_file_from_fd(int fd, void **buf, loff_t *size, loff_t max_size, if (!f.file) goto out; - ret = kernel_read_file(f.file, buf, size, max_size, id); + ret = kernel_read_file(f.file, buf, max_size, id); out: fdput(f); return ret; diff --git a/include/linux/kernel_read_file.h b/include/linux/kernel_read_file.h index 78cf3d7dc835..0ca0bdbed1bd 100644 --- a/include/linux/kernel_read_file.h +++ b/include/linux/kernel_read_file.h @@ -36,16 +36,16 @@ static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id) } int kernel_read_file(struct file *file, - void **buf, loff_t *size, loff_t max_size, + void **buf, loff_t max_size, enum kernel_read_file_id id); int kernel_read_file_from_path(const char *path, - void **buf, loff_t *size, loff_t max_size, + void **buf, loff_t max_size, enum kernel_read_file_id id); int kernel_read_file_from_path_initns(const char *path, - void **buf, loff_t *size, loff_t max_size, + void **buf, loff_t max_size, enum kernel_read_file_id id); int kernel_read_file_from_fd(int fd, - void **buf, loff_t *size, loff_t max_size, + void **buf, loff_t max_size, enum kernel_read_file_id id); #endif /* _LINUX_KERNEL_READ_FILE_H */ diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 1cc82557f4c1..b20cfde8a01d 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -220,13 +220,12 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, { int ret; void *ldata; - loff_t size; ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf, - &size, INT_MAX, READING_KEXEC_IMAGE); - if (ret) + INT_MAX, READING_KEXEC_IMAGE); + if (ret < 0) return ret; - image->kernel_buf_len = size; + image->kernel_buf_len = ret; /* Call arch image probe handlers */ ret = arch_kexec_kernel_image_probe(image, image->kernel_buf, @@ -243,11 +242,12 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, /* It is possible that there no initramfs is being loaded */ if (!(flags & KEXEC_FILE_NO_INITRAMFS)) { ret = kernel_read_file_from_fd(initrd_fd, &image->initrd_buf, - &size, INT_MAX, + INT_MAX, READING_KEXEC_INITRAMFS); - if (ret) + if (ret < 0) goto out; - image->initrd_buf_len = size; + image->initrd_buf_len = ret; + ret = 0; } if (cmdline_len) { diff --git a/kernel/module.c b/kernel/module.c index 4218abd272ee..9faa6322f17b 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -4035,7 +4035,6 @@ SYSCALL_DEFINE3(init_module, void __user *, umod, SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) { struct load_info info = { }; - loff_t size; void *hdr = NULL; int err; @@ -4049,12 +4048,12 @@ SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags) |MODULE_INIT_IGNORE_VERMAGIC)) return -EINVAL; - err = kernel_read_file_from_fd(fd, &hdr, &size, INT_MAX, + err = kernel_read_file_from_fd(fd, &hdr, INT_MAX, READING_MODULE); - if (err) + if (err < 0) return err; info.hdr = hdr; - info.len = size; + info.len = err; return load_module(&info, uargs, flags); } diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c index f8869be45d8f..97661ffabc4e 100644 --- a/security/integrity/digsig.c +++ b/security/integrity/digsig.c @@ -171,16 +171,17 @@ int __init integrity_add_key(const unsigned int id, const void *data, int __init integrity_load_x509(const unsigned int id, const char *path) { void *data = NULL; - loff_t size; + size_t size; int rc; key_perm_t perm; - rc = kernel_read_file_from_path(path, &data, &size, 0, + rc = kernel_read_file_from_path(path, &data, 0, READING_X509_CERTIFICATE); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); return rc; } + size = rc; perm = (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW | KEY_USR_READ; diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index e13ffece3726..602f52717757 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -275,7 +275,7 @@ static ssize_t ima_read_policy(char *path) { void *data = NULL; char *datap; - loff_t size; + size_t size; int rc, pathlen = strlen(path); char *p; @@ -284,11 +284,13 @@ static ssize_t ima_read_policy(char *path) datap = path; strsep(&datap, "\n"); - rc = kernel_read_file_from_path(path, &data, &size, 0, READING_POLICY); + rc = kernel_read_file_from_path(path, &data, 0, READING_POLICY); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); return rc; } + size = rc; + rc = 0; datap = data; while (size > 0 && (p = strsep(&datap, "\n"))) {