lua-resty-mysql variable self.packet_no bug

[vensontao]

lualib/resty/mysql.lua:191: bad argument #1 to 'strchar' (invalid value)

in mysql.lua file， the fucntion _send_packet(self, req, size)
self.packet_no = self.packet_no + 1
local packet = _set_byte3(size) .. strchar(self.packet_no) .. req

the variables self.packet_no can be 255 +1 =256, produce errors： bad argument #1 to 'strchar' (invalid value)
detail error information see openresty group url：
https://groups.google.com/forum/#!topic/openresty/j3a-x75x0D0

[agentzh]

@vensontao Yeah, this is a corner case that the client sends more than 255 packets through a single resty.mysql object. We should check the integer overflow. Will you try the following patch on your side?

diff --git a/lib/resty/mysql.lua b/lib/resty/mysql.lua
index 008a267..fc8bb74 100644
--- a/lib/resty/mysql.lua
+++ b/lib/resty/mysql.lua
@@ -184,11 +184,16 @@ end
 local function _send_packet(self, req, size)
     local sock = self.sock

-    self.packet_no = self.packet_no + 1
+    local packet_no = self.packet_no
+    packet_no = packet_no + 1
+    if packet_no >= 256 then
+        packet_no = 1
+    end
+    self.packet_no = packet_no

     -- print("packet no: ", self.packet_no)

-    local packet = _set_byte3(size) .. strchar(self.packet_no) .. req
+    local packet = _set_byte3(size) .. strchar(packet_no) .. req

     -- print("sending packet: ", _dump(packet))

[vensontao]

Great, This problem has been solved. thanks very much!

[vensontao]

Great，I try the following patch you gave, the problem has been solved. And I close the issues on GitHub. Thank you very much! 发件人: Yichun Zhang [mailto:notifications@github.com] 发送时间: 2016年12月14日 5:16 收件人: openresty/openresty 抄送: vensontao; Mention 主题: Re: [openresty/openresty] lua-resty-mysql variable self.packet_no bug (#212) @vensontao <https://github.com/vensontao> Yeah, this is a corner case that the client sends more than 255 packets through a single resty.mysql object. We should check the integer overflow. Will you try the following patch on your side? diff --git a/lib/resty/mysql.lua b/lib/resty/mysql.lua index 008a267..fc8bb74 100644 --- a/lib/resty/mysql.lua +++ b/lib/resty/mysql.lua @@ -184,11 +184,16 @@ end local function _send_packet(self, req, size) local sock = self.sock - self.packet_no = self.packet_no + 1 + local packet_no = self.packet_no + packet_no = packet_no + 1 + if packet_no >= 256 then + packet_no = 1 + end + self.packet_no = packet_no

…

-- print("packet no: ", self.packet_no) - local packet = _set_byte3(size) .. strchar(self.packet_no) .. req + local packet = _set_byte3(size) .. strchar(packet_no) .. req

-- print("sending packet: ", _dump(packet)) — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#212 (comment)> , or mute the thread <https://github.com/notifications/unsubscribe-auth/APAJkHEsp_sVx7Er3bqerT6LTXzIBitbks5rHwshgaJpZM4LLWgt> . <https://github.com/notifications/beacon/APAJkLBhDgPLCq_hRpFZlnw5E5lXYV74ks5rHwshgaJpZM4LLWgt.gif>

[vensontao]

we can fix this issue in the next version of openresty/lua-resty-mysql.