diff options
| author | Jaegeuk Kim <jaegeuk@kernel.org> | 2018-11-14 12:40:30 -0800 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2019-01-02 16:17:11 -0800 |
| commit | bec98df4142c3d4e761a35bfeb53da0a9544955a (patch) | |
| tree | 64de73ef840e57940d722aa633351877edcda7e4 | |
| parent | c461cc70cf27ea100c722e7ac7f15a442e450fd3 (diff) | |
f2fs: check memory boundary by insane namelen
If namelen is corrupted to have very long value, fill_dentries can copy
wrong memory area.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| -rw-r--r-- | fs/f2fs/dir.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c index eedc07b46a52..5cd19f2e6e04 100644 --- a/fs/f2fs/dir.c +++ b/fs/f2fs/dir.c @@ -808,6 +808,17 @@ int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, de_name.name = d->filename[bit_pos]; de_name.len = le16_to_cpu(de->name_len); + /* check memory boundary before moving forward */ + bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len)); + if (unlikely(bit_pos > d->max)) { + f2fs_msg(sbi->sb, KERN_WARNING, + "%s: corrupted namelen=%d, run fsck to fix.", + __func__, le16_to_cpu(de->name_len)); + set_sbi_flag(sbi, SBI_NEED_FSCK); + err = -EINVAL; + goto out; + } + if (f2fs_encrypted_inode(d->inode)) { int save_len = fstr->len; @@ -830,7 +841,6 @@ int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, if (readdir_ra) f2fs_ra_node_page(sbi, le32_to_cpu(de->ino)); - bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len)); ctx->pos = start_pos + bit_pos; } out: |