xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

f2fs: be aware of invalid filename length

Browse Source 
The filename length in dirent of may become zero-sized after random junk
data injection, once encounter such dirent, find_target_dentry or
f2fs_add_inline_entries will run into an infinite loop. So let f2fs being
aware of that to avoid deadloop.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Chao Yu
2016-04-27 22:22:20 +08:00
committed by Jaegeuk Kim
parent ae9b9a9d3c
commit a4a13f582c
2 changed files with 11 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
fs/f2fs/dir.c
View File

@@ -101,11 +101,6 @@ static struct f2fs_dir_entry *find_in_block(struct page *dentry_page,
else
kunmap(dentry_page);
/*
* For the most part, it should be a bug when name_len is zero.
* We stop here for figuring out where the bugs has occurred.
*/
f2fs_bug_on(F2FS_P_SB(dentry_page), d.max < 0);
return de;
}
@@ -130,6 +125,11 @@ struct f2fs_dir_entry *find_target_dentry(struct fscrypt_name *fname,
de = &d->dentry[bit_pos];
if (unlikely(!de->name_len)) {
bit_pos++;
continue;
}
/* encrypted case */
de_name.name = d->filename[bit_pos];
de_name.len = le16_to_cpu(de->name_len);
@@ -147,10 +147,6 @@ struct f2fs_dir_entry *find_target_dentry(struct fscrypt_name *fname,
*max_slots = max_len;
max_len = 0;
/* remain bug on condition */
if (unlikely(!de->name_len))
d->max = -1;
bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
}