Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757007Ab1ETAzJ (ORCPT ); Thu, 19 May 2011 20:55:09 -0400 Received: from e1.ny.us.ibm.com ([32.97.182.141]:35855 "EHLO e1.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752739Ab1ETAzG (ORCPT ); Thu, 19 May 2011 20:55:06 -0400 Subject: Re: [PATCH v5 05/21] ima: move ima_file_free before releasing the file From: Mimi Zohar To: "Serge E. Hallyn" Cc: linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, James Morris , David Safford , Andrew Morton , Greg KH , Dmitry Kasatkin , Mimi Zohar In-Reply-To: <20110519220649.GA4332@mail.hallyn.com> References: <1305557115-15652-1-git-send-email-zohar@linux.vnet.ibm.com> <1305557115-15652-6-git-send-email-zohar@linux.vnet.ibm.com> <20110519220649.GA4332@mail.hallyn.com> Content-Type: text/plain; charset="UTF-8" Date: Thu, 19 May 2011 20:55:01 -0400 Message-ID: <1305852901.2528.40.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 (2.30.3-1.fc13) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1768 Lines: 43 On Thu, 2011-05-19 at 17:06 -0500, Serge E. Hallyn wrote: > Quoting Mimi Zohar (zohar@linux.vnet.ibm.com): > > Integrity appraisal measures files on file_free and stores the file > > measurement as an xattr. Measure the file before releasing it. > > Can you put a bit more in the commit msg about why? What's magic > about the fs-specific release function? ima_file_free(), called on __fput(), currently flags files that have changed, so that the file is re-measured. However, for appraising a files's integrity, flagging the file is not enough. The file's security.ima xattr must be updated to reflect any changes. This patch moves releasing the file to after calculating the new file hash. > > Signed-off-by: Mimi Zohar > > Acked-by: Serge Hallyn > > --- > > fs/file_table.c | 2 +- > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > diff --git a/fs/file_table.c b/fs/file_table.c > > index 01e4c1e..33f54a1 100644 > > --- a/fs/file_table.c > > +++ b/fs/file_table.c > > @@ -243,10 +243,10 @@ static void __fput(struct file *file) > > if (file->f_op && file->f_op->fasync) > > file->f_op->fasync(-1, file, 0); > > } > > + ima_file_free(file); > > if (file->f_op && file->f_op->release) > > file->f_op->release(inode, file); > > security_file_free(file); > > - ima_file_free(file); > > if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL && > > !(file->f_mode & FMODE_PATH))) { > > cdev_put(inode->i_cdev); > > -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/