Removes add64 r10, imm special handling in execution.

Author: Lichtso

src/interpreter.rs

@@ -13,7 +13,7 @@
 //! Interpreter for eBPF programs.
 
 use crate::{
-    ebpf::{self, FRAME_PTR_REG},
+    ebpf,
     elf::Executable,
     error::{EbpfError, ProgramResult},
     program::BuiltinFunction,
@@ -188,16 +188,6 @@ impl<'a, 'b, C: ContextObject> Interpreter<'a, 'b, C> {
         }
 
         match insn.opc {
-            ebpf::ADD64_IMM if dst == FRAME_PTR_REG && self.executable.get_sbpf_version().dynamic_stack_frames() => {
-                // Let the stack overflow. For legitimate programs, this is a nearly
-                // impossible condition to hit since programs are metered and we already
-                // enforce a maximum call depth. For programs that intentionally mess
-                // around with the stack pointer, MemoryRegion::map will return
-                // InvalidVirtualAddress(stack_ptr) once an invalid stack address is
-                // accessed.
-                self.reg[ebpf::FRAME_PTR_REG] = self.reg[ebpf::FRAME_PTR_REG].overflowing_add(insn.imm as u64).0;
-            }
-
             ebpf::LD_DW_IMM if !self.executable.get_sbpf_version().disable_lddw() => {
                 ebpf::augment_lddw_unchecked(self.program, &mut insn);
                 self.reg[dst] = insn.imm as u64;

src/jit.rs

@@ -422,10 +422,6 @@ impl<'a, C: ContextObject> JitCompiler<'a, C> {
             let target_pc = (self.pc as isize + insn.off as isize + 1) as usize;
 
             match insn.opc {
-                ebpf::ADD64_IMM if insn.dst == FRAME_PTR_REG as u8 && self.executable.get_sbpf_version().dynamic_stack_frames() => {
-                    self.emit_ins(X86Instruction::alu(OperandSize::S64, 0x81, 0, REGISTER_MAP[FRAME_PTR_REG], insn.imm, None));
-                }
-
                 ebpf::LD_DW_IMM if !self.executable.get_sbpf_version().disable_lddw() => {
                     self.emit_validate_and_profile_instruction_count(false, Some(self.pc + 2));
                     self.pc += 1;