3 ms·
That's not a a86 thing; it's to avoid generating a modrm byte that can be decoded as a return instruction[0] for ROP gadgets. $ zasm -Mx86 -='add al al;add a
by a1369209993 4y ago
That's not a a86 thing; it's to avoid generating a modrm byte that can be decoded as a return instruction[0] for ROP gadgets.
$ zasm -Mx86 -='add al al;add al dl;add dl al'
000000 - 02 C0 00 D0 02 D0 |...... |
$ hex C3 | ndisasm -au -
00000000 C3 ret
0: C2, C3, CA, or CB, so modrm (ax/cx) (dx/bx)
- rep_lodsb 4y agoROP wasn't a concept back then. From the manual of the latest version of A86: A86 assembler package V4.05 January 14, 2000 The entire package is Copyright 2000 Eric Isaacson. All rights reserved.