From patchwork Wed Jul 29 17:58:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11691531 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 5710D138C for ; Wed, 29 Jul 2020 17:59:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3AFB42084D for ; Wed, 29 Jul 2020 17:59:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="cfJA1yoL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728068AbgG2R76 (ORCPT ); Wed, 29 Jul 2020 13:59:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727861AbgG2R7B (ORCPT ); Wed, 29 Jul 2020 13:59:01 -0400 Received: from mail-pj1-x1041.google.com (mail-pj1-x1041.google.com [IPv6:2607:f8b0:4864:20::1041]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C42ACC0619DE for ; Wed, 29 Jul 2020 10:59:01 -0700 (PDT) Received: by mail-pj1-x1041.google.com with SMTP id k71so2245407pje.0 for ; Wed, 29 Jul 2020 10:59:01 -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=jU2VJx8QGZyxpfIxF1fo6TrEFAt4UxU1npx7vrAKnZ8=; b=cfJA1yoLRS1EuKB6SD/UZbVHyHN2opnYoF3ty8DxzWqNZIqnI10tluoUMCaXOaLBuQ +UqNF0lhPk6ughdqC/jshZTZ0iLCkahWZgnil8QJ2Q/jgcCqlWZN9Ehlh1yFsO8+qmhK xWfmFj9xY99va9E6S8WpZMcLDlcIrEat3nR7o= 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=jU2VJx8QGZyxpfIxF1fo6TrEFAt4UxU1npx7vrAKnZ8=; b=nnTPK+ED7bGl5cKerCjnxwNRBrVN5QGv/UN4ie/m/+PfnoaOspWDk+KxVeHZDtbplo yFJp01beQD08E0p+I/5Vu14nDdkYwRijXGyHiYAslkYSc7JRtoS4RcYrZNHI+Ct8ILuF uydwiVWeTMuYO+8dKXaBqZIPZ9wtnvjORE9VZ5SpUqx6hSl+xKL2weLZNJtzeIqHY8aX rmDcoUfb1Vi7uqJAUT3p2YGeFVL84DR6uTwBFWmOg9btUb8uUld1RaTlPN/Hblm7j5XS djH2LEjPkv9SmZkj+njSIwkTu282CHyDkgQ+uIGv8+EQ0faHn88iQDd18mIEOoz71xnI wluQ== X-Gm-Message-State: AOAM532KTYVnAtSfzaS0o5Uvx5au4SdWqTpYsj79/JgBk1vhCuMTDMDe TImekrBlOAbmTalYejVBmsXoPg== X-Google-Smtp-Source: ABdhPJy6PwoNCyC8rVomCYFtW5CtQ1E6nIw60akd0htXreCsvmisuIrvcMKK3sC9okq9AG7t/KI7oA== X-Received: by 2002:a17:902:ea8c:: with SMTP id x12mr15675315plb.60.1596045541329; Wed, 29 Jul 2020 10:59:01 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id z13sm3142496pfq.220.2020.07.29.10.58.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Jul 2020 10:58:58 -0700 (PDT) From: Kees Cook To: Greg Kroah-Hartman Cc: Kees Cook , Scott Branden , Mimi Zohar , Luis Chamberlain , 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 v4 08/17] fs/kernel_read_file: Add file_size output argument Date: Wed, 29 Jul 2020 10:58:36 -0700 Message-Id: <20200729175845.1745471-9-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200729175845.1745471-1-keescook@chromium.org> References: <20200729175845.1745471-1-keescook@chromium.org> MIME-Version: 1.0 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org In preparation for adding partial read support, add an optional output argument to kernel_read_file*() that reports the file size so callers can reason more easily about their reading progress. Acked-by: Scott Branden Reviewed-by: Mimi Zohar Reviewed-by: Luis Chamberlain Signed-off-by: Kees Cook Reviewed-by: James Morris --- drivers/base/firmware_loader/main.c | 1 + fs/kernel_read_file.c | 19 +++++++++++++------ include/linux/kernel_read_file.h | 4 ++++ kernel/kexec_file.c | 4 ++-- kernel/module.c | 2 +- security/integrity/digsig.c | 2 +- security/integrity/ima/ima_fs.c | 2 +- 7 files changed, 23 insertions(+), 11 deletions(-) diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 9b425437afe6..6a5d407279e3 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -495,6 +495,7 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, /* load firmware files from the mount namespace of init */ rc = kernel_read_file_from_path_initns(path, &buffer, msize, + NULL, READING_FIRMWARE); if (rc < 0) { if (rc != -ENOENT) diff --git a/fs/kernel_read_file.c b/fs/kernel_read_file.c index e21a76001fff..2e29c38eb4df 100644 --- a/fs/kernel_read_file.c +++ b/fs/kernel_read_file.c @@ -14,6 +14,8 @@ * @buf_size will be ignored) * @buf_size size of buf, if already allocated. If @buf not * allocated, this is the largest size to allocate. + * @file_size if non-NULL, the full size of @file will be + * written here. * @id the kernel_read_file_id identifying the type of * file contents being read (for LSMs to examine) * @@ -22,7 +24,8 @@ * */ int kernel_read_file(struct file *file, void **buf, - size_t buf_size, enum kernel_read_file_id id) + size_t buf_size, size_t *file_size, + enum kernel_read_file_id id) { loff_t i_size, pos; ssize_t bytes = 0; @@ -49,6 +52,8 @@ int kernel_read_file(struct file *file, void **buf, ret = -EFBIG; goto out; } + if (file_size) + *file_size = i_size; if (!*buf) *buf = allocated = vmalloc(i_size); @@ -91,7 +96,8 @@ int kernel_read_file(struct file *file, void **buf, EXPORT_SYMBOL_GPL(kernel_read_file); int kernel_read_file_from_path(const char *path, void **buf, - size_t buf_size, enum kernel_read_file_id id) + size_t buf_size, size_t *file_size, + enum kernel_read_file_id id) { struct file *file; int ret; @@ -103,14 +109,14 @@ int kernel_read_file_from_path(const char *path, void **buf, if (IS_ERR(file)) return PTR_ERR(file); - ret = kernel_read_file(file, buf, buf_size, id); + ret = kernel_read_file(file, buf, buf_size, file_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, - size_t buf_size, + size_t buf_size, size_t *file_size, enum kernel_read_file_id id) { struct file *file; @@ -129,13 +135,14 @@ 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, buf_size, id); + ret = kernel_read_file(file, buf, buf_size, file_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, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id) { struct fd f = fdget(fd); @@ -144,7 +151,7 @@ int kernel_read_file_from_fd(int fd, void **buf, size_t buf_size, if (!f.file) goto out; - ret = kernel_read_file(f.file, buf, buf_size, id); + ret = kernel_read_file(f.file, buf, buf_size, file_size, id); out: fdput(f); return ret; diff --git a/include/linux/kernel_read_file.h b/include/linux/kernel_read_file.h index 910039e7593e..023293eaf948 100644 --- a/include/linux/kernel_read_file.h +++ b/include/linux/kernel_read_file.h @@ -37,15 +37,19 @@ static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id) int kernel_read_file(struct file *file, void **buf, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id); int kernel_read_file_from_path(const char *path, void **buf, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id); int kernel_read_file_from_path_initns(const char *path, void **buf, size_t buf_size, + size_t *file_size, enum kernel_read_file_id id); int kernel_read_file_from_fd(int fd, void **buf, size_t buf_size, + size_t *file_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 eda19ca256a3..878ca684a3a1 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -222,7 +222,7 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, void *ldata; ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf, - INT_MAX, READING_KEXEC_IMAGE); + INT_MAX, NULL, READING_KEXEC_IMAGE); if (ret < 0) return ret; image->kernel_buf_len = ret; @@ -242,7 +242,7 @@ 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, - INT_MAX, + INT_MAX, NULL, READING_KEXEC_INITRAMFS); if (ret < 0) goto out; diff --git a/kernel/module.c b/kernel/module.c index 0792ce3bf643..16558bc842de 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -4004,7 +4004,7 @@ 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, INT_MAX, + err = kernel_read_file_from_fd(fd, &hdr, INT_MAX, NULL, READING_MODULE); if (err < 0) return err; diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c index 04f779c4f5ed..8a523dfd7fd7 100644 --- a/security/integrity/digsig.c +++ b/security/integrity/digsig.c @@ -175,7 +175,7 @@ int __init integrity_load_x509(const unsigned int id, const char *path) int rc; key_perm_t perm; - rc = kernel_read_file_from_path(path, &data, INT_MAX, + rc = kernel_read_file_from_path(path, &data, INT_MAX, NULL, READING_X509_CERTIFICATE); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c index 692b83e82edf..5fc56ccb6678 100644 --- a/security/integrity/ima/ima_fs.c +++ b/security/integrity/ima/ima_fs.c @@ -284,7 +284,7 @@ static ssize_t ima_read_policy(char *path) datap = path; strsep(&datap, "\n"); - rc = kernel_read_file_from_path(path, &data, INT_MAX, READING_POLICY); + rc = kernel_read_file_from_path(path, &data, INT_MAX, NULL, READING_POLICY); if (rc < 0) { pr_err("Unable to open file: %s (%d)", path, rc); return rc;