Fix - Missing BPF_MUL result sign extension (#518)

* Adds test. * Fixes old BPF_MUL missing result sign extension in JIT.
solana-labs · Sep 20, 2023 · ef0264d · ef0264d
1 parent 9a09aeb
commit ef0264d
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Showing 2 changed files with 15 additions and 4 deletions.
diff --git a/src/jit.rs b/src/jit.rs
@@ -495,9 +495,9 @@ impl<'a, C: ContextObject> JitCompiler<'a, C> {
                     self.emit_ins(X86Instruction::alu(OperandSize::S64, 0x63, dst, dst, 0, None)); // sign extend i32 to i64
                 },
                 ebpf::MUL32_IMM | ebpf::DIV32_IMM | ebpf::MOD32_IMM if !self.executable.get_sbpf_version().enable_pqr() =>
-                    self.emit_product_quotient_remainder(OperandSize::S32, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MOD, (insn.opc & ebpf::BPF_ALU_OP_MASK) != ebpf::BPF_MUL, false, dst, dst, Some(insn.imm)),
+                    self.emit_product_quotient_remainder(OperandSize::S32, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MOD, (insn.opc & ebpf::BPF_ALU_OP_MASK) != ebpf::BPF_MUL, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MUL, dst, dst, Some(insn.imm)),
                 ebpf::MUL32_REG | ebpf::DIV32_REG | ebpf::MOD32_REG if !self.executable.get_sbpf_version().enable_pqr() =>
-                    self.emit_product_quotient_remainder(OperandSize::S32, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MOD, (insn.opc & ebpf::BPF_ALU_OP_MASK) != ebpf::BPF_MUL, false, src, dst, None),
+                    self.emit_product_quotient_remainder(OperandSize::S32, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MOD, (insn.opc & ebpf::BPF_ALU_OP_MASK) != ebpf::BPF_MUL, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MUL, src, dst, None),
                 ebpf::OR32_IMM   => self.emit_sanitized_alu(OperandSize::S32, 0x09, 1, dst, insn.imm),
                 ebpf::OR32_REG   => self.emit_ins(X86Instruction::alu(OperandSize::S32, 0x09, src, dst, 0, None)),
                 ebpf::AND32_IMM  => self.emit_sanitized_alu(OperandSize::S32, 0x21, 4, dst, insn.imm),
@@ -562,9 +562,9 @@ impl<'a, C: ContextObject> JitCompiler<'a, C> {
                 }
                 ebpf::SUB64_REG  => self.emit_ins(X86Instruction::alu(OperandSize::S64, 0x29, src, dst, 0, None)),
                 ebpf::MUL64_IMM | ebpf::DIV64_IMM | ebpf::MOD64_IMM if !self.executable.get_sbpf_version().enable_pqr() =>
-                    self.emit_product_quotient_remainder(OperandSize::S64, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MOD, (insn.opc & ebpf::BPF_ALU_OP_MASK) != ebpf::BPF_MUL, false, dst, dst, Some(insn.imm)),
+                    self.emit_product_quotient_remainder(OperandSize::S64, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MOD, (insn.opc & ebpf::BPF_ALU_OP_MASK) != ebpf::BPF_MUL, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MUL, dst, dst, Some(insn.imm)),
                 ebpf::MUL64_REG | ebpf::DIV64_REG | ebpf::MOD64_REG if !self.executable.get_sbpf_version().enable_pqr() =>
-                    self.emit_product_quotient_remainder(OperandSize::S64, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MOD, (insn.opc & ebpf::BPF_ALU_OP_MASK) != ebpf::BPF_MUL, false, src, dst, None),
+                    self.emit_product_quotient_remainder(OperandSize::S64, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MOD, (insn.opc & ebpf::BPF_ALU_OP_MASK) != ebpf::BPF_MUL, (insn.opc & ebpf::BPF_ALU_OP_MASK) == ebpf::BPF_MUL, src, dst, None),
                 ebpf::OR64_IMM   => self.emit_sanitized_alu(OperandSize::S64, 0x09, 1, dst, insn.imm),
                 ebpf::OR64_REG   => self.emit_ins(X86Instruction::alu(OperandSize::S64, 0x09, src, dst, 0, None)),
                 ebpf::AND64_IMM  => self.emit_sanitized_alu(OperandSize::S64, 0x21, 4, dst, insn.imm),

diff --git a/tests/execution.rs b/tests/execution.rs
@@ -3748,6 +3748,17 @@ fn test_mul() {
         TestContextObject::new(4),
         ProgramResult::Ok(0x100000004),
     );
+    test_interpreter_and_jit_asm!(
+        "
+        mov r0, -1
+        mul32 r0, 4
+        exit",
+        config,
+        [],
+        (),
+        TestContextObject::new(3),
+        ProgramResult::Ok(0xFFFFFFFFFFFFFFFC),
+    );
 }
 
 #[test]