From: Namjae Jeon <linkinjeon@xxxxxxxxxx> commit b5e5f9dfc915ff05b41dff56181e1dae101712bd upstream. FileOffset should not be greater than BeyondFinalZero in FSCTL_ZERO_DATA. And don't call ksmbd_vfs_zero_data() if length is zero. Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Hyunchul Lee <hyc.lee@xxxxxxxxx> Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ksmbd/smb2pdu.c | 29 ++++++++++++++++++----------- 1 file changed, 18 insertions(+), 11 deletions(-) --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -7684,7 +7684,7 @@ int smb2_ioctl(struct ksmbd_work *work) { struct file_zero_data_information *zero_data; struct ksmbd_file *fp; - loff_t off, len; + loff_t off, len, bfz; if (!test_tree_conn_flag(work->tcon, KSMBD_TREE_CONN_FLAG_WRITABLE)) { ksmbd_debug(SMB, @@ -7701,19 +7701,26 @@ int smb2_ioctl(struct ksmbd_work *work) zero_data = (struct file_zero_data_information *)&req->Buffer[0]; - fp = ksmbd_lookup_fd_fast(work, id); - if (!fp) { - ret = -ENOENT; + off = le64_to_cpu(zero_data->FileOffset); + bfz = le64_to_cpu(zero_data->BeyondFinalZero); + if (off > bfz) { + ret = -EINVAL; goto out; } - off = le64_to_cpu(zero_data->FileOffset); - len = le64_to_cpu(zero_data->BeyondFinalZero) - off; - - ret = ksmbd_vfs_zero_data(work, fp, off, len); - ksmbd_fd_put(work, fp); - if (ret < 0) - goto out; + len = bfz - off; + if (len) { + fp = ksmbd_lookup_fd_fast(work, id); + if (!fp) { + ret = -ENOENT; + goto out; + } + + ret = ksmbd_vfs_zero_data(work, fp, off, len); + ksmbd_fd_put(work, fp); + if (ret < 0) + goto out; + } break; } case FSCTL_QUERY_ALLOCATED_RANGES: