There are tests all over the SMB1 code to check that srv_send_smb fails, but it never returns false

[Richard Sharpe]

On Fri, Jul 19, 2013 at 12:57 PM, Richard Sharpe
<realrichardsharpe at gmail.com> wrote:
> Hi folks,
>
> We see the following code in srv_send_smb (even in master):
>
>         ret = write_data(sconn->sock, buf_out+nwritten, len - nwritten);
>         if (ret <= 0) {
>
>                 char addr[INET6_ADDRSTRLEN];
>                 /*
>                  * Try and give an error message saying what
>                  * client failed.
>                  */
>                 DEBUG(1,("pid[%d] Error writing %d bytes to client %s.
> %d. (%s)\n",
>                          (int)sys_getpid(), (int)len,
>                          get_peer_addr(sconn->sock, addr, sizeof(addr)),
>                          (int)ret, strerror(errno) ));
>
>                 srv_free_enc_buffer(buf_out);
>                 goto out;
>         }
>
>         SMB_PERFCOUNT_SET_MSGLEN_OUT(pcd, len);
>         srv_free_enc_buffer(buf_out);
> out:
>         SMB_PERFCOUNT_END(pcd);
>
>         smbd_unlock_socket(sconn);
>         return true;
> }
>
> Even if the write to the socket/fd fails, we never return false and
> will keep reading stuff off of the input buffer until it is exhausted
> and then we will exit. That seems somewhat incorrect.

I think this is the fix:

diff --git a/source3/smbd/process.c b/source3/smbd/process.c
index 5ef0fd3..210a281 100644
--- a/source3/smbd/process.c
+++ b/source3/smbd/process.c
@@ -194,7 +194,7 @@ out:
        SMB_PERFCOUNT_END(pcd);

        smbd_unlock_socket(sconn);
-       return true;
+       return ret > 0;
 }

 /*******************************************************************

-- 
Regards,
Richard Sharpe
(何以解憂？唯有杜康。--曹操)
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