tree 88047dd2960dbcba1529f1081ea69bee6c691a25
parent 0e658fb0518da7c3292da99a301e4405affec8fa
author Willy Tarreau <w@1wt.eu> 1480171924 +0100
committer Willy Tarreau <w@1wt.eu> 1480172307 +0100
encoding latin1

BUG/MEDIUM: proxy: return "none" and "unknown" for unknown LB algos

When a backend doesn't use any known LB algorithm, backend_lb_algo_str()
returns NULL. It used to cause "nil" to be printed in the stats dump
since version 1.4 but causes 1.7 to try to parse this NULL to encode
it as a CSV string, causing a crash on "show stat" in this case.

The only situation where this can happen is when "transparent" or
"dispatch" are used in a proxy, in which case the LB algorithm is
BE_LB_ALGO_NONE. Thus now we explicitly report "none" when this
situation is detected, and we preventively report "unknown" if any
unknown algorithm is detected, which may happen if such an algo is
added in the future and the function is not updated.

This fix must be backported to 1.7 and may be backported as far as
1.4, though it has less impact there.