From b5e5f9dfc915ff05b41dff56181e1dae101712bd Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Sun, 19 Jun 2022 22:37:17 +0900 Subject: ksmbd: check invalid FileOffset and BeyondFinalZero in FSCTL_ZERO_DATA 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@vger.kernel.org Reviewed-by: Hyunchul Lee Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/ksmbd/smb2pdu.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index e35930867893..94ab1dcd80e7 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -7700,7 +7700,7 @@ 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, @@ -7717,19 +7717,26 @@ 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; + 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; + 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: -- cgit v1.2.3