I've collected several of them.
First goes MTVK's 16 photos:
MTVK.com
Second goes a glimpse by chrisinsouthkorea to crowd and some freaks including bands on the stage:
koreabridge.net
Short metion at Korea Herald:
Korea Herald
Other short mention at Korea Times:
Pentaport Rock Festival
Several photos at Russian site:
Безумие корейского рока
Short overview by cnngo:
Korea's month of rock continues with Pentaport Rock Festival
