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    Subject[PATCH 4.14 004/195] cifs: Fix autonegotiate security settings mismatch
    Date
    4.14-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Daniel N Pettersson <danielnp@axis.com>

    commit 9aca7e454415f7878b28524e76bebe1170911a88 upstream.

    Autonegotiation gives a security settings mismatch error if the SMB
    server selects an SMBv3 dialect that isn't SMB3.02. The exact error is
    "protocol revalidation - security settings mismatch".
    This can be tested using Samba v4.2 or by setting the global Samba
    setting max protocol = SMB3_00.

    The check that fails in smb3_validate_negotiate is the dialect
    verification of the negotiate info response. This is because it tries
    to verify against the protocol_id in the global smbdefault_values. The
    protocol_id in smbdefault_values is SMB3.02.
    In SMB2_negotiate the protocol_id in smbdefault_values isn't updated,
    it is global so it probably shouldn't be, but server->dialect is.

    This patch changes the check in smb3_validate_negotiate to use
    server->dialect instead of server->vals->protocol_id. The patch works
    with autonegotiate and when using a specific version in the vers mount
    option.

    Signed-off-by: Daniel N Pettersson <danielnp@axis.com>
    Signed-off-by: Steve French <smfrench@gmail.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    fs/cifs/smb2pdu.c | 3 +--
    1 file changed, 1 insertion(+), 2 deletions(-)

    --- a/fs/cifs/smb2pdu.c
    +++ b/fs/cifs/smb2pdu.c
    @@ -733,8 +733,7 @@ int smb3_validate_negotiate(const unsign
    }

    /* check validate negotiate info response matches what we got earlier */
    - if (pneg_rsp->Dialect !=
    - cpu_to_le16(tcon->ses->server->vals->protocol_id))
    + if (pneg_rsp->Dialect != cpu_to_le16(tcon->ses->server->dialect))
    goto vneg_out;

    if (pneg_rsp->SecurityMode != cpu_to_le16(tcon->ses->server->sec_mode))

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