6.1-stable review patch. If anyone has any objections, please let me know.
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From: Namjae Jeon linkinjeon@kernel.org
commit 44a3059c4c8cc635a1fb2afd692d0730ca1ba4b6 upstream.
If client send multiple session setup requests to ksmbd, Preauh_HashValue race condition could happen. There is no need to free sess->Preauh_HashValue at session setup phase. It can be freed together with session at connection termination phase.
Cc: stable@vger.kernel.org Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-27661 Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/smb/server/smb2pdu.c | 4 ---- 1 file changed, 4 deletions(-)
--- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -1842,8 +1842,6 @@ int smb2_sess_setup(struct ksmbd_work *w ksmbd_conn_set_good(conn); sess->state = SMB2_SESSION_VALID; } - kfree(sess->Preauth_HashValue); - sess->Preauth_HashValue = NULL; } else if (conn->preferred_auth_mech == KSMBD_AUTH_NTLMSSP) { if (negblob->MessageType == NtLmNegotiate) { rc = ntlm_negotiate(work, negblob, negblob_len, rsp); @@ -1870,8 +1868,6 @@ int smb2_sess_setup(struct ksmbd_work *w kfree(preauth_sess); } } - kfree(sess->Preauth_HashValue); - sess->Preauth_HashValue = NULL; } else { pr_info_ratelimited("Unknown NTLMSSP message type : 0x%x\n", le32_to_cpu(negblob->MessageType));