So I was finally able to get my hands on an AC86U and track down the weird issues introduced with this new device and my script.
One of the major ones seems to be non ascii characters randomly being inserted to files I do various modifications on with grep/sed/echo. The real problem is the null character when being processed by IPSet crashes the router with the following message.
Code:
Feb 14 10:00:17 kernel: _ Reboot message ... _______________________________________________________
Feb 14 10:00:18 kernel: Unable to handle kernel NULL pointer dereference at virtual address 00000000pgd = ffffffc006627000[00000000] *pgd=00000000051ec003, *pud=00000000051ec003, *pmd=000000000540b003, *pte=0000000000000000Internal error: Oops: 96000007 [#1] PREEMPT SMPModules linked in: ip_set_list_set init_addr( (null) - (null)), core_addr(ffffffbffc312000 - ffffffbffc313a40) ip_set_hash_ip init_addr( (null) - (null)), core_addr(ffffffbffc309000 - ffffffbffc30c95
Feb 14 10:00:19 kernel: x28: ffffffc0058938d4 x27: ffffffc00abb2308 x26: ffffffc00bb3c400 x25: ffffffc0055367d8 x24: 0000000000000001 x23: 0000000000000140 x22: ffffffc0058938d8 x21: ffffffc00a7b00c0 x20: 000000001f910000 x19: ffffffc0055367e0 x18: 0000000000000000 x17: 0000000000000000 x16: ffffffc00039ff18 x15: 4009000800000000 x14: 00000000f7706660 x13: 0000000000000001 x12: 0000000000000028 x11: 0101010101010101 x10: 7f7f7f7f7f7f7f7f x9 : 0000000000000000 x8 : 0000000000000000 x7 : 00000000fffffff
Feb 14 10:00:19 kernel: ____________________________________________________________________________
Now with that being said, I can't reproduce this every time, it happens maybe %60 of the time a new "list" is generated by Skynets banmalware function. This issue is not apparent on any other devices (random characters being inserted that is, I haven't tested yet if IPSet crashes on other devices when trying to list/restore entries with this character in it).
In the example here, 934 "null" characters were added to the end of the file for no apparent reason, sometimes the random characters replace other text too so the location/point of input isn't consistent.
So the short version is, do you have any idea what would be causing an issue of this nature on only this device, and secondly can any mitigation be put in place so at-least IPSet doesn't hard reboot the router when dealing with such characters in both the restore/save commands.
IPSet v6.35 is also out, I don't see any changes directly related to an issue of this nature but potentially it has be addressed.
I will try my best to track it down further, but the hard reboots make it quite a slow process.