Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: reject repeated SMB2 NEGOTIATE requests Unauthenticated client can send multiple successful SMB2 NEGOTIATE requests on one connection before SESSION_SETUP. While the connection is in KSMBD_SESS_NEED_SETUP, smb2_handle_negotiate() accepts another SMB3.1.1 NEGOTIATE and overwrites conn->preauth_info with a new allocation. Only the final allocation is freed when the connection is released, leaking one object for every additional successful request. A repeated SMB2 NEGOTIATE after a dialect has been selected is a protocol violation. MS-SMB2 section 3.3.5.4 requires the server to disconnect without replying in this case. Set the connection exiting when rejecting the request, in addition to suppressing the response. Reject SMB2 NEGOTIATE unless the connection is new or is waiting for the SMB2 NEGOTIATE that follows an SMB1 multi-protocol negotiate. Serialize both SMB1 and SMB2 negotiation paths under conn->srv_mutex, since they update connection-wide dialect and negotiation state. Move the locking contract to ksmbd_smb_negotiate_common(), where the state and dialect are selected, and add ksmbd_conn_new() for consistent state access.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 to < 0b1390cf2b6b91723b37c0909dd123f7a5eba1a7affectede2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 to < fd6a6c43f96b40a08a22ff62f08d194a49741c8aaffectede2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 to < 81e21cb7bd1479bb5238e0004a7e0110452c610baffectede2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 to < 7fb8dbeb3f2868ae836ca12311d89aed16fc2927affectede2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 to < a60b5da05e318d9a364dbac38c347c7f24e625e7affectede2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 to < 7e02cb30e8a1f5fc78cb10b220b06020e36d0bbeaffectede2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 to < cb469993b3a61a72653770856d37af616d72d05faffected
Linux Linux
Default version status: affected
5.15affected0 to < 5.15unaffected5.15.217 to ≤ 5.15.*unaffected6.1.184 to ≤ 6.1.*unaffected6.6.153 to ≤ 6.6.*unaffected6.12.105 to ≤ 6.12.*unaffected6.18.44 to ≤ 6.18.*unaffected7.1.8 to ≤ 7.1.*unaffected7.2 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/0b1390cf2b6b91723b37c0909dd123f7a5eba1a7 ↗
- https://git.kernel.org/stable/c/fd6a6c43f96b40a08a22ff62f08d194a49741c8a ↗
- https://git.kernel.org/stable/c/81e21cb7bd1479bb5238e0004a7e0110452c610b ↗
- https://git.kernel.org/stable/c/7fb8dbeb3f2868ae836ca12311d89aed16fc2927 ↗
- https://git.kernel.org/stable/c/a60b5da05e318d9a364dbac38c347c7f24e625e7 ↗
- https://git.kernel.org/stable/c/7e02cb30e8a1f5fc78cb10b220b06020e36d0bbe ↗
- https://git.kernel.org/stable/c/cb469993b3a61a72653770856d37af616d72d05f ↗