Reviewed-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
On Fri, Jul 3, 2020 at 7:30 PM Roberto Bergantinos Corpas
<rbergant@xxxxxxxxxx> wrote:
>
> If server returns ERRBaduid but does not reset transport connection,
> we'll keep sending command with a non-valid UID for the server as long
> as transport is healthy, without actually recovering. This have been
> observed on the field.
>
> This patch adds ERRBaduid handling so that we set CifsNeedReconnect.
>
> map_and_check_smb_error() can be modified to extend use cases.
>
> Signed-off-by: Roberto Bergantinos Corpas <rbergant@xxxxxxxxxx>
> ---
> fs/cifs/cifsproto.h | 1 +
> fs/cifs/netmisc.c | 27 +++++++++++++++++++++++++++
> fs/cifs/transport.c | 2 +-
> 3 files changed, 29 insertions(+), 1 deletion(-)
>
> diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
> index 948bf3474db1..d72cf20ab048 100644
> --- a/fs/cifs/cifsproto.h
> +++ b/fs/cifs/cifsproto.h
> @@ -149,6 +149,7 @@ extern int decode_negTokenInit(unsigned char *security_blob, int length,
> extern int cifs_convert_address(struct sockaddr *dst, const char *src, int len);
> extern void cifs_set_port(struct sockaddr *addr, const unsigned short int port);
> extern int map_smb_to_linux_error(char *buf, bool logErr);
> +extern int map_and_check_smb_error(struct mid_q_entry *mid, bool logErr);
> extern void header_assemble(struct smb_hdr *, char /* command */ ,
> const struct cifs_tcon *, int /* length of
> fixed section (word count) in two byte units */);
> diff --git a/fs/cifs/netmisc.c b/fs/cifs/netmisc.c
> index 9b41436fb8db..ae9679a27181 100644
> --- a/fs/cifs/netmisc.c
> +++ b/fs/cifs/netmisc.c
> @@ -881,6 +881,33 @@ map_smb_to_linux_error(char *buf, bool logErr)
> return rc;
> }
>
> +int
> +map_and_check_smb_error(struct mid_q_entry *mid, bool logErr)
> +{
> + int rc;
> + struct smb_hdr *smb = (struct smb_hdr *)mid->resp_buf;
> +
> + rc = map_smb_to_linux_error((char *)smb, logErr);
> + if (rc == -EACCES && !(smb->Flags2 & SMBFLG2_ERR_STATUS)) {
> + /* possible ERRBaduid */
> + __u8 class = smb->Status.DosError.ErrorClass;
> + __u16 code = le16_to_cpu(smb->Status.DosError.Error);
> +
> + /* switch can be used to handle different errors */
> + if (class == ERRSRV && code == ERRbaduid) {
> + cifs_dbg(FYI, "Server returned 0x%x, reconnecting session...\n",
> + code);
> + spin_lock(&GlobalMid_Lock);
> + if (mid->server->tcpStatus != CifsExiting)
> + mid->server->tcpStatus = CifsNeedReconnect;
> + spin_unlock(&GlobalMid_Lock);
> + }
> + }
> +
> + return rc;
> +}
> +
> +
> /*
> * calculate the size of the SMB message based on the fixed header
> * portion, the number of word parameters and the data portion of the message
> diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
> index cb3ee916f527..e8dbd6b55559 100644
> --- a/fs/cifs/transport.c
> +++ b/fs/cifs/transport.c
> @@ -935,7 +935,7 @@ cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
> }
>
> /* BB special case reconnect tid and uid here? */
> - return map_smb_to_linux_error(mid->resp_buf, log_error);
> + return map_and_check_smb_error(mid, log_error);
> }
>
> struct mid_q_entry *
> --
> 2.21.0
>
