food inside node breaker makes server go kakapuku

[retsil2]

as lemonfox3008 earlier reported,

I accidently left some food in a node breaker on a server and when it activated via blinky plant the server crashed. I have no access to the error logs but i guess it was because the food was attempted to be "used" and was "eaten" by the machine which could not support it. This is a MAJOR problem as a troublemaker could destroy a server with just a nodebreaker an apple and a blinky plant

we can confirm, this indeed happens. we found out because we have a player who keeps building berry farms, and his pipes go past the sides of nodebreakers, so berries at times enter them and "clog" them, so to speak, which manifests as a crash:

2018-11-30 10:11:26: ERROR[Main]: ServerError: AsyncErr: environment_Step: Runtime error from mod 'pipeworks' in callback environment_Step(): /home/minetest/minetest/bin/../mods/stamina/init.lua:29: attempt to call method 'get_attribute' (a nil value)
2018-11-30 10:11:26: ERROR[Main]: stack traceback:
2018-11-30 10:11:26: ERROR[Main]:       /home/minetest/minetest/bin/../mods/stamina/init.lua:29: in function 'get_int_attribute'
2018-11-30 10:11:26: ERROR[Main]:       /home/minetest/minetest/bin/../mods/stamina/init.lua:283: in function 'eat'
2018-11-30 10:11:26: ERROR[Main]:       /home/minetest/minetest/bin/../mods/stamina/init.lua:263: in function </home/minetest/minetest/bin/../mods/stamina/init.lua:261>
2018-11-30 10:11:26: ERROR[Main]:       (tail call): ?
2018-11-30 10:11:26: ERROR[Main]:       ...n/../mods/dreambuilder_modpack/pipeworks/wielder.lua:385: in function 'act'
2018-11-30 10:11:26: ERROR[Main]:       ...n/../mods/dreambuilder_modpack/pipeworks/wielder.lua:169: in function 'wielder_on'
2018-11-30 10:11:26: ERROR[Main]:       ...n/../mods/dreambuilder_modpack/pipeworks/wielder.lua:205: in function 'action_on'
2018-11-30 10:11:26: ERROR[Main]:       ...n/../mods/dreambuilder_modpack/mesecons/internal.lua:190: in function '?'
2018-11-30 10:11:26: ERROR[Main]:       ..../mods/dreambuilder_modpack/mesecons/actionqueue.lua:93: in function 'execute'
2018-11-30 10:11:26: ERROR[Main]:       ..../mods/dreambuilder_modpack/mesecons/actionqueue.lua:84: in function '?'
2018-11-30 10:11:26: ERROR[Main]:       ...e/minetest/minetest/bin/../builtin/game/register.lua:412: in function <...e/minetest/minetest/bin/../builtin/game/register.lua:392>
2018-11-30 10:11:26: ERROR[Main]: stack traceback:

[retsil2]

the fake player in pipeworks does not have the requisite method. this quick-and-dirty patch seems to fix it, but we cannot be totally sure it's totally sufficient.

diff --git a/init.lua b/init.lua
index 260cee8..69c0b24 100644
--- a/init.lua
+++ b/init.lua
@@ -26,6 +26,9 @@ SPRINT_JUMP = 0.1             -- how much higher player can jump if satiated
 SPRINT_DRAIN = 0.35            -- how fast to drain satation while sprinting (0-1)
 
 local function get_int_attribute(player, key)
+        if player.get_attribute == nil then
+                return nil
+        end
        local level = player:get_attribute(key)
        if level then
                return tonumber(level)
@@ -35,6 +38,9 @@ local function get_int_attribute(player, key)
 end
 
 local function stamina_update_level(player, level)
+        if player.get_attribute == nil then
+                return nil
+        end
        local old = get_int_attribute(player, "stamina:level")
 
        if level == old then  -- To suppress HUD update

[thomasrudin]

#21 should fix your issue

[fluxionary]

I can't replicate this issue currently, I believe it has been fixed.