From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sheng Yong Subject: Re: [PATCH] fsck.f2fs: check and fix i_namelen to avoid double free Date: Fri, 15 Dec 2017 18:01:53 +0800 Message-ID: <506aa086-5cba-a2ee-332d-07e79e5aa764@huawei.com> References: <1513319130-114230-1-git-send-email-yunlong.song@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1513319130-114230-1-git-send-email-yunlong.song@huawei.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Yunlong Song , jaegeuk@kernel.org, chao@kernel.org, yuchao0@huawei.com, yunlong.song@icloud.com Cc: miaoxie@huawei.com, bintian.wang@huawei.com, heyunlei@huawei.com, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org List-Id: linux-f2fs-devel.lists.sourceforge.net On 2017/12/15 14:25, Yunlong Song wrote: > Signed-off-by: Yunlong Song > --- > fsck/fsck.c | 19 ++++++++++++++++--- > 1 file changed, 16 insertions(+), 3 deletions(-) > > diff --git a/fsck/fsck.c b/fsck/fsck.c > index 2212aa3..8ff4e4b 100644 > --- a/fsck/fsck.c > +++ b/fsck/fsck.c > @@ -643,7 +643,7 @@ void fsck_chk_inode_blk(struct f2fs_sb_info *sbi, u32 nid, > u64 i_blocks = le64_to_cpu(node_blk->i.i_blocks); > int ofs = get_extra_isize(node_blk); > unsigned char *en; > - int namelen; > + int namelen, i_namelen; > unsigned int idx = 0; > int need_fix = 0; > int ret; > @@ -850,8 +850,21 @@ skip_blkcnt_fix: > en = malloc(F2FS_NAME_LEN + 1); > ASSERT(en); > > - namelen = convert_encrypted_name(node_blk->i.i_name, > - le32_to_cpu(node_blk->i.i_namelen), > + i_namelen = le32_to_cpu(node_blk->i.i_namelen); > + namelen = strlen((const char *)node_blk->i.i_name); Hi, Yunlong The strlen doesn't work for encrypted i_name. strlen may get a wrong namelen. thanks, Sheng > + if (i_namelen > F2FS_NAME_LEN) { > + ASSERT_MSG("ino: 0x%x has i_namelen: 0x%x, " > + "but has %d characters for name", > + nid, i_namelen, namelen); > + if (c.fix_on) { > + FIX_MSG("[0x%x] i_namelen=0x%x -> 0x%x", nid, i_namelen, > + namelen); > + node_blk->i.i_namelen = cpu_to_le32(namelen); > + need_fix = 1; > + } > + i_namelen = namelen; > + } > + namelen = convert_encrypted_name(node_blk->i.i_name, i_namelen, > en, file_enc_name(&node_blk->i)); > en[namelen] = '\0'; > if (ftype == F2FS_FT_ORPHAN) >