From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.136]:47426 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750892AbcGQGYb (ORCPT ); Sun, 17 Jul 2016 02:24:31 -0400 From: Jaegeuk Kim To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Cc: Jaegeuk Kim Subject: [PATCH 1/3] f2fs: avoid memory allocation failure due to a long length Date: Sat, 16 Jul 2016 23:24:25 -0700 Message-Id: <20160717062427.56718-1-jaegeuk@kernel.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: We need to avoid ENOMEM due to unexpected long length. Signed-off-by: Jaegeuk Kim --- fs/f2fs/file.c | 46 ++++++++++++++++++++++++++++------------------ 1 file changed, 28 insertions(+), 18 deletions(-) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 17b3059..3573b07 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1039,33 +1039,43 @@ static int __clone_blkaddrs(struct inode *src_inode, struct inode *dst_inode, static int __exchange_data_block(struct inode *src_inode, struct inode *dst_inode, pgoff_t src, pgoff_t dst, - int len, bool full) + pgoff_t len, bool full) { block_t *src_blkaddr; int *do_replace; + pgoff_t olen; int ret; - src_blkaddr = f2fs_kvzalloc(sizeof(block_t) * len, GFP_KERNEL); - if (!src_blkaddr) - return -ENOMEM; + while (len) { + olen = min((pgoff_t)4 * ADDRS_PER_BLOCK, len); - do_replace = f2fs_kvzalloc(sizeof(int) * len, GFP_KERNEL); - if (!do_replace) { - kvfree(src_blkaddr); - return -ENOMEM; - } + src_blkaddr = f2fs_kvzalloc(sizeof(block_t) * olen, GFP_KERNEL); + if (!src_blkaddr) + return -ENOMEM; - ret = __read_out_blkaddrs(src_inode, src_blkaddr, do_replace, src, len); - if (ret) - goto roll_back; + do_replace = f2fs_kvzalloc(sizeof(int) * olen, GFP_KERNEL); + if (!do_replace) { + kvfree(src_blkaddr); + return -ENOMEM; + } - ret = __clone_blkaddrs(src_inode, dst_inode, src_blkaddr, - do_replace, src, dst, len, full); - if (ret) - goto roll_back; + ret = __read_out_blkaddrs(src_inode, src_blkaddr, + do_replace, src, olen); + if (ret) + goto roll_back; - kvfree(src_blkaddr); - kvfree(do_replace); + ret = __clone_blkaddrs(src_inode, dst_inode, src_blkaddr, + do_replace, src, dst, olen, full); + if (ret) + goto roll_back; + + src += olen; + dst += olen; + len -= olen; + + kvfree(src_blkaddr); + kvfree(do_replace); + } return 0; roll_back: -- 2.8.3