"EFI PART" in middle of file?

[johnsanc]

I experienced a really weird issue where one of my files appears to be corrupted. No change in modify time or anything, but there is exactly 512 bytes of the file that is replaced with a bunch of zeroes and what looks like part of a GUID partition table. Has anyone ever experienced something like this? Any idea what could cause this in an unRAID array?

 

Note this disk reports no issues in the Smart stats.

 

45 46 49 20 50 41 52 54 00 00 01 00 5C 00 00 00
B2 D1 CB C3 00 00 00 00 AF 2A 81 A3 03 00 00 00
01 00 00 00 00 00 00 00 22 00 00 00 00 00 00 00
8E 2A 81 A3 03 00 00 00 E8 AA 45 BE F7 99 9B 47
B6 71 85 D2 BF 8A BF 78 8F 2A 81 A3 03 00 00 00
80 00 00 00 80 00 00 00 27 05 B2 F9 00 00 00 00

 

https://en.wikipedia.org/wiki/GUID_Partition_Table

 

[pwm]

Basically two options - software bug somewhere, or a transfer error where the intended write address got corrupted resulting in the wrong 512 byte sector on the drive getting updated.

[johnsanc]

I’m no expert, but it just seems really weird that guid partition table info would be injected into the middle of a file... I’m almost certain it happened sometime after the initial creation because i have a synced version elsewhere that is correct.