nginx error connect to php5-fpm.sock failed (13: Permission denied)

Question

I update nginx to 1.4.7 and php to 5.5.12, After that I got the 502 error. Before I update everything works fine.

Answer 1

@Xander's solution works, but does not persist after a reboot.

I found that I had to change listen.mode to 0660 in /etc/php5/fpm/pool.d/www.conf.

Sample from www.conf:

; Set permissions for unix socket, if one is used. In Linux, read/write
; permissions must be set in order to allow connections from a web server. Many
; BSD-derived systems allow connections regardless of permissions. 
; Default Values: user and group are set as the running user
;                 mode is set to 0660
;listen.owner = www-data
;listen.group = www-data
;listen.mode = 0660

Edit: Per @Chris Burgess, I've changed this to the more secure method.

I removed the comment for listen.mode, .group and .owner:

listen.owner = www-data
listen.group = www-data
listen.mode = 0660

/var/run Only holds information about the running system since last boot, e.g., currently logged-in users and running daemons. (http://en.wikipedia.org/wiki/Filesystem_Hierarchy_Standard#Directory_structure).

Side note:

My php5-fpm -v Reports: PHP 5.4.28-1+deb.sury.org~precise+1. The issue did happen after a recent update as well.