diff options
| author | Namjae Jeon <linkinjeon@kernel.org> | 2023-05-03 08:51:12 +0900 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2023-05-03 23:03:02 -0500 |
| commit | 30210947a343b6b3ca13adc9bfc88e1543e16dd5 (patch) | |
| tree | b975ba955a52288885c013b107e7114523c3c24b /fs/ksmbd | |
| parent | abcc506a9a71976a8b4c9bf3ee6efd13229c1e19 (diff) | |
ksmbd: fix racy issue under cocurrent smb2 tree disconnect
There is UAF issue under cocurrent smb2 tree disconnect.
This patch introduce TREE_CONN_EXPIRE flags for tcon to avoid cocurrent
access.
Cc: stable@vger.kernel.org
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-20592
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/ksmbd')
| -rw-r--r-- | fs/ksmbd/mgmt/tree_connect.c | 10 | ||||
| -rw-r--r-- | fs/ksmbd/mgmt/tree_connect.h | 3 | ||||
| -rw-r--r-- | fs/ksmbd/smb2pdu.c | 3 |
3 files changed, 14 insertions, 2 deletions
diff --git a/fs/ksmbd/mgmt/tree_connect.c b/fs/ksmbd/mgmt/tree_connect.c index aa9c138d5851..f07a05f37651 100644 --- a/fs/ksmbd/mgmt/tree_connect.c +++ b/fs/ksmbd/mgmt/tree_connect.c @@ -109,7 +109,15 @@ int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess, struct ksmbd_tree_connect *ksmbd_tree_conn_lookup(struct ksmbd_session *sess, unsigned int id) { - return xa_load(&sess->tree_conns, id); + struct ksmbd_tree_connect *tcon; + + tcon = xa_load(&sess->tree_conns, id); + if (tcon) { + if (test_bit(TREE_CONN_EXPIRE, &tcon->status)) + tcon = NULL; + } + + return tcon; } struct ksmbd_share_config *ksmbd_tree_conn_share(struct ksmbd_session *sess, diff --git a/fs/ksmbd/mgmt/tree_connect.h b/fs/ksmbd/mgmt/tree_connect.h index 0f97ddc1e39c..700df36cf3e3 100644 --- a/fs/ksmbd/mgmt/tree_connect.h +++ b/fs/ksmbd/mgmt/tree_connect.h @@ -14,6 +14,8 @@ struct ksmbd_share_config; struct ksmbd_user; struct ksmbd_conn; +#define TREE_CONN_EXPIRE 1 + struct ksmbd_tree_connect { int id; @@ -25,6 +27,7 @@ struct ksmbd_tree_connect { int maximal_access; bool posix_extensions; + unsigned long status; }; struct ksmbd_tree_conn_status { diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c index 0ca1c5daf60a..cb93fd231f4e 100644 --- a/fs/ksmbd/smb2pdu.c +++ b/fs/ksmbd/smb2pdu.c @@ -2053,11 +2053,12 @@ int smb2_tree_disconnect(struct ksmbd_work *work) ksmbd_debug(SMB, "request\n"); - if (!tcon) { + if (!tcon || test_and_set_bit(TREE_CONN_EXPIRE, &tcon->status)) { struct smb2_tree_disconnect_req *req = smb2_get_msg(work->request_buf); ksmbd_debug(SMB, "Invalid tid %d\n", req->hdr.Id.SyncId.TreeId); + rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED; smb2_set_err_rsp(work); return 0; |