Anyway, first I thought my ROM had corrupted. So, I wiped everything and re-installed a new ROM. However, the error didn't go away, again it will come up randomly. So I thought it was due to f2fs format since I had formatted /data, /data/media and /cache partitions to f2fs using arter97's recovery (I was using his kernel also). So I formatted them back to ext4, also changed my recovery back to philz's and installed stock CM rom. But again the error started coming
So I thought maybe it was due to I had been restoring apps via Titanium Backup which is causing the issue. So I stopped restoring apps, however It didn't work either, I was still getting the error. I started flashing many different ROMs (CM, omni, aosp, custom touchwiz) , gapps combination's (banks, 0day PA, others), factory resetting 10s of times, using MegaWipe script to format everything, removing the memory card permanently, however the error is still coming.
So in the end, I flashed stock samsung 4.3 ROM via ODIN and did a factory reset, however the error is still coming
I don't know what else to do ? Is my phone NAND corrupted ? Is there any test I can do to make sure ?