6.6-stable review patch. If anyone has any objections, please let me know.
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From: Namjae Jeon linkinjeon@kernel.org
commit c8b5b7c5da7d0c31c9b7190b4a7bba5281fc4780 upstream.
The Client send malformed smb2 negotiate request. ksmbd return error response. Subsequently, the client can send smb2 session setup even thought conn->preauth_info is not allocated. This patch add KSMBD_SESS_NEED_SETUP status of connection to ignore session setup request if smb2 negotiate phase is not complete.
Cc: stable@vger.kernel.org Tested-by: Steve French stfrench@microsoft.com Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-26505 Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Jan Alexander Preissler akendo@akendo.eu Signed-off-by: Sujana Subramaniam sujana.subramaniam@sap.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/smb/server/connection.h | 11 +++++++++++ fs/smb/server/mgmt/user_session.c | 4 ++-- fs/smb/server/smb2pdu.c | 14 +++++++++++--- 3 files changed, 24 insertions(+), 5 deletions(-)
--- a/fs/smb/server/connection.h +++ b/fs/smb/server/connection.h @@ -27,6 +27,7 @@ enum { KSMBD_SESS_EXITING, KSMBD_SESS_NEED_RECONNECT, KSMBD_SESS_NEED_NEGOTIATE, + KSMBD_SESS_NEED_SETUP, KSMBD_SESS_RELEASING };
@@ -195,6 +196,11 @@ static inline bool ksmbd_conn_need_negot return READ_ONCE(conn->status) == KSMBD_SESS_NEED_NEGOTIATE; }
+static inline bool ksmbd_conn_need_setup(struct ksmbd_conn *conn) +{ + return READ_ONCE(conn->status) == KSMBD_SESS_NEED_SETUP; +} + static inline bool ksmbd_conn_need_reconnect(struct ksmbd_conn *conn) { return READ_ONCE(conn->status) == KSMBD_SESS_NEED_RECONNECT; @@ -225,6 +231,11 @@ static inline void ksmbd_conn_set_need_n WRITE_ONCE(conn->status, KSMBD_SESS_NEED_NEGOTIATE); }
+static inline void ksmbd_conn_set_need_setup(struct ksmbd_conn *conn) +{ + WRITE_ONCE(conn->status, KSMBD_SESS_NEED_SETUP); +} + static inline void ksmbd_conn_set_need_reconnect(struct ksmbd_conn *conn) { WRITE_ONCE(conn->status, KSMBD_SESS_NEED_RECONNECT); --- a/fs/smb/server/mgmt/user_session.c +++ b/fs/smb/server/mgmt/user_session.c @@ -373,12 +373,12 @@ void destroy_previous_session(struct ksm ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_RECONNECT); err = ksmbd_conn_wait_idle_sess_id(conn, id); if (err) { - ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_NEGOTIATE); + ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_SETUP); goto out; } ksmbd_destroy_file_table(&prev_sess->file_table); prev_sess->state = SMB2_SESSION_EXPIRED; - ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_NEGOTIATE); + ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_SETUP); out: up_write(&conn->session_lock); up_write(&sessions_table_lock); --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -1252,7 +1252,7 @@ int smb2_handle_negotiate(struct ksmbd_w }
conn->srv_sec_mode = le16_to_cpu(rsp->SecurityMode); - ksmbd_conn_set_need_negotiate(conn); + ksmbd_conn_set_need_setup(conn);
err_out: if (rc) @@ -1273,6 +1273,9 @@ static int alloc_preauth_hash(struct ksm if (sess->Preauth_HashValue) return 0;
+ if (!conn->preauth_info) + return -ENOMEM; + sess->Preauth_HashValue = kmemdup(conn->preauth_info->Preauth_HashValue, PREAUTH_HASHVALUE_SIZE, GFP_KERNEL); if (!sess->Preauth_HashValue) @@ -1688,6 +1691,11 @@ int smb2_sess_setup(struct ksmbd_work *w
ksmbd_debug(SMB, "Received request for session setup\n");
+ if (!ksmbd_conn_need_setup(conn) && !ksmbd_conn_good(conn)) { + work->send_no_response = 1; + return rc; + } + WORK_BUFFERS(work, req, rsp);
rsp->StructureSize = cpu_to_le16(9); @@ -1919,7 +1927,7 @@ out_err: if (try_delay) { ksmbd_conn_set_need_reconnect(conn); ssleep(5); - ksmbd_conn_set_need_negotiate(conn); + ksmbd_conn_set_need_setup(conn); } } smb2_set_err_rsp(work); @@ -2249,7 +2257,7 @@ int smb2_session_logoff(struct ksmbd_wor ksmbd_free_user(sess->user); sess->user = NULL; } - ksmbd_all_conn_set_status(sess_id, KSMBD_SESS_NEED_NEGOTIATE); + ksmbd_all_conn_set_status(sess_id, KSMBD_SESS_NEED_SETUP);
rsp->StructureSize = cpu_to_le16(4); err = ksmbd_iov_pin_rsp(work, rsp, sizeof(struct smb2_logoff_rsp));