From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f176.google.com ([209.85.223.176]:34640 "EHLO mail-io0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755935AbcBDRqP (ORCPT ); Thu, 4 Feb 2016 12:46:15 -0500 Received: by mail-io0-f176.google.com with SMTP id 9so101530095iom.1 for ; Thu, 04 Feb 2016 09:46:15 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1454526390-19792-13-git-send-email-zohar@linux.vnet.ibm.com> References: <1454526390-19792-1-git-send-email-zohar@linux.vnet.ibm.com> <1454526390-19792-13-git-send-email-zohar@linux.vnet.ibm.com> Date: Thu, 4 Feb 2016 09:46:15 -0800 Message-ID: Subject: Re: [PATCH v3 12/22] vfs: define kernel_read_file_from_path From: Kees Cook To: Mimi Zohar Cc: linux-security-module , "Luis R. Rodriguez" , Kexec Mailing List , linux-modules@vger.kernel.org, David Howells , David Woodhouse , Dmitry Torokhov , Dmitry Kasatkin , Eric Biederman , Rusty Russell Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-modules@vger.kernel.org List-ID: On Wed, Feb 3, 2016 at 11:06 AM, Mimi Zohar wrote: > This patch defines kernel_read_file_from_path(), a wrapper for the VFS > common kernel_read_file(). > > Changelog: > - Separated from the IMA patch > > Signed-off-by: Mimi Zohar Acked-by: Kees Cook -Kees > --- > fs/exec.c | 22 ++++++++++++++++++++++ > include/linux/fs.h | 2 ++ > 2 files changed, 24 insertions(+) > > diff --git a/fs/exec.c b/fs/exec.c > index cd2b5b2..5629958 100644 > --- a/fs/exec.c > +++ b/fs/exec.c > @@ -884,6 +884,28 @@ out: > } > EXPORT_SYMBOL_GPL(kernel_read_file); > > +int kernel_read_file_from_path(char *path, void **buf, loff_t *size, > + loff_t max_size, enum kernel_read_file_id id) > +{ > + struct file *file; > + int ret; > + > + if (!path || !*path) > + return -EINVAL; > + > + file = filp_open(path, O_RDONLY, 0); > + if (IS_ERR(file)) { > + ret = PTR_ERR(file); > + pr_err("Unable to open file: %s (%d)", path, ret); > + return ret; > + } > + > + ret = kernel_read_file(file, buf, size, max_size, id); > + fput(file); > + return ret; > +} > +EXPORT_SYMBOL_GPL(kernel_read_file_from_path); > + > ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len) > { > ssize_t res = vfs_read(file, (void __user *)addr, len, &pos); > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 1458ca5..962c491 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -2533,6 +2533,8 @@ enum kernel_read_file_id { > extern int kernel_read(struct file *, loff_t, char *, unsigned long); > extern int kernel_read_file(struct file *, void **, loff_t *, loff_t, > enum kernel_read_file_id); > +extern int kernel_read_file_from_path(char *, void **, loff_t *, loff_t, > + enum kernel_read_file_id); > extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t); > extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *); > extern struct file * open_exec(const char *); > -- > 2.1.0 > -- Kees Cook Chrome OS & Brillo Security