From: Nikanth Karthikesan Subject: [PATCH] ext4: Prevent creation of files larger than RLIMIT_FSIZE using fallocate Date: Tue, 4 May 2010 11:15:04 +0530 Message-ID: <201005041115.04400.knikanth@suse.de> References: <201004281854.49730.knikanth@suse.de> <201005030953.45157.knikanth@suse.de> <20100503065945.GA13756@amitarora.in.ibm.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: "Amit K. Arora" , Andrew Morton , coly.li@suse.de, Nick Piggin , Alexander Viro , linux-fsdevel@vger.kernel.org, Eelis , Amit Arora , Christoph Hellwig To: "Theodore Ts'o" , Andreas Dilger , linux-ext4@vger.kernel.org Return-path: Received: from cantor2.suse.de ([195.135.220.15]:53675 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753458Ab0EDFnY (ORCPT ); Tue, 4 May 2010 01:43:24 -0400 In-Reply-To: <20100503065945.GA13756@amitarora.in.ibm.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: I assumed that Amit would send a patch with s-o-b, if not, please take this patch. Thanks Nikanth Prevent creation of files larger than RLIMIT_FSIZE using fallocate. Currently using posix_fallocate one can bypass an RLIMIT_FSIZE limit and create a file larger than the limit. Add a check for that. Signed-off-by: Nikanth Karthikesan --- diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 236b834..39b8123 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3672,6 +3672,11 @@ long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len) */ credits = ext4_chunk_trans_blocks(inode, max_blocks); mutex_lock(&inode->i_mutex); + ret = inode_newsize_ok(inode, (len + offset)); + if (ret) { + mutex_unlock(&inode->i_mutex); + return ret; + } retry: while (ret >= 0 && ret < max_blocks) { block = block + ret;