From 946f10963fdaa8b9e7a02f4aaef87a07402105b0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Alexander=20Mei=C3=9Fner?= Date: Thu, 5 Dec 2024 13:44:44 +0100 Subject: [PATCH] Removes sign extension of the immediate values in unsigned PQR instructions. --- src/interpreter.rs | 6 +++--- src/jit.rs | 14 ++++++++++---- tests/execution.rs | 34 ++++++++++++++++++++++------------ 3 files changed, 35 insertions(+), 19 deletions(-) diff --git a/src/interpreter.rs b/src/interpreter.rs index 573a7cb7..dcb38f5b 100644 --- a/src/interpreter.rs +++ b/src/interpreter.rs @@ -403,7 +403,7 @@ impl<'a, 'b, C: ContextObject> Interpreter<'a, 'b, C> { ebpf::LMUL32_REG if self.executable.get_sbpf_version().enable_pqr() => self.reg[dst] = (self.reg[dst] as u32).wrapping_mul(self.reg[src] as u32) as u64, ebpf::LMUL64_IMM if self.executable.get_sbpf_version().enable_pqr() => self.reg[dst] = self.reg[dst].wrapping_mul(insn.imm as u64), ebpf::LMUL64_REG if self.executable.get_sbpf_version().enable_pqr() => self.reg[dst] = self.reg[dst].wrapping_mul(self.reg[src]), - ebpf::UHMUL64_IMM if self.executable.get_sbpf_version().enable_pqr() => self.reg[dst] = (self.reg[dst] as u128).wrapping_mul(insn.imm as u64 as u128).wrapping_shr(64) as u64, + ebpf::UHMUL64_IMM if self.executable.get_sbpf_version().enable_pqr() => self.reg[dst] = (self.reg[dst] as u128).wrapping_mul(insn.imm as u32 as u128).wrapping_shr(64) as u64, ebpf::UHMUL64_REG if self.executable.get_sbpf_version().enable_pqr() => self.reg[dst] = (self.reg[dst] as u128).wrapping_mul(self.reg[src] as u128).wrapping_shr(64) as u64, ebpf::SHMUL64_IMM if self.executable.get_sbpf_version().enable_pqr() => self.reg[dst] = (self.reg[dst] as i64 as i128).wrapping_mul(insn.imm as i128).wrapping_shr(64) as u64, ebpf::SHMUL64_REG if self.executable.get_sbpf_version().enable_pqr() => self.reg[dst] = (self.reg[dst] as i64 as i128).wrapping_mul(self.reg[src] as i64 as i128).wrapping_shr(64) as u64, @@ -415,7 +415,7 @@ impl<'a, 'b, C: ContextObject> Interpreter<'a, 'b, C> { self.reg[dst] = (self.reg[dst] as u32 / self.reg[src] as u32) as u64; }, ebpf::UDIV64_IMM if self.executable.get_sbpf_version().enable_pqr() => { - self.reg[dst] /= insn.imm as u64; + self.reg[dst] /= insn.imm as u32 as u64; } ebpf::UDIV64_REG if self.executable.get_sbpf_version().enable_pqr() => { throw_error!(DivideByZero; self, self.reg[src], u64); @@ -429,7 +429,7 @@ impl<'a, 'b, C: ContextObject> Interpreter<'a, 'b, C> { self.reg[dst] = (self.reg[dst] as u32 % self.reg[src] as u32) as u64; }, ebpf::UREM64_IMM if self.executable.get_sbpf_version().enable_pqr() => { - self.reg[dst] %= insn.imm as u64; + self.reg[dst] %= insn.imm as u32 as u64; } ebpf::UREM64_REG if self.executable.get_sbpf_version().enable_pqr() => { throw_error!(DivideByZero; self, self.reg[src], u64); diff --git a/src/jit.rs b/src/jit.rs index 36d09a15..7d0e4570 100644 --- a/src/jit.rs +++ b/src/jit.rs @@ -674,14 +674,20 @@ impl<'a, C: ContextObject> JitCompiler<'a, C> { ebpf::LMUL32_IMM | ebpf::LMUL64_IMM | ebpf::UHMUL64_IMM | ebpf::SHMUL64_IMM | ebpf::UDIV32_IMM | ebpf::UDIV64_IMM | ebpf::UREM32_IMM | ebpf::UREM64_IMM | ebpf::SDIV32_IMM | ebpf::SDIV64_IMM | ebpf::SREM32_IMM | ebpf::SREM64_IMM - if self.executable.get_sbpf_version().enable_pqr() => + if self.executable.get_sbpf_version().enable_pqr() => { + let signed = insn.opc & (1 << 7) != 0; + let mut imm = insn.imm; + if !signed { + imm &= u32::MAX as i64; + } self.emit_product_quotient_remainder( if insn.opc & (1 << 4) != 0 { OperandSize::S64 } else { OperandSize::S32 }, insn.opc & (1 << 5) != 0, insn.opc & (1 << 6) != 0, - insn.opc & (1 << 7) != 0, - dst, dst, Some(insn.imm), - ), + signed, + dst, dst, Some(imm), + ) + } ebpf::LMUL32_REG | ebpf::LMUL64_REG | ebpf::UHMUL64_REG | ebpf::SHMUL64_REG | ebpf::UDIV32_REG | ebpf::UDIV64_REG | ebpf::UREM32_REG | ebpf::UREM64_REG | ebpf::SDIV32_REG | ebpf::SDIV64_REG | ebpf::SREM32_REG | ebpf::SREM64_REG diff --git a/tests/execution.rs b/tests/execution.rs index 9573c918..0989119e 100644 --- a/tests/execution.rs +++ b/tests/execution.rs @@ -701,9 +701,9 @@ fn test_be64() { #[test] fn test_pqr() { let mut prog = [0; 48]; - prog[0] = ebpf::MOV64_IMM; + prog[0] = ebpf::MOV32_IMM; prog[8] = ebpf::HOR64_IMM; - prog[16] = ebpf::MOV64_IMM; + prog[16] = ebpf::MOV32_IMM; prog[17] = 1; // dst = R1 prog[24] = ebpf::HOR64_IMM; prog[25] = 1; // dst = R1 @@ -716,21 +716,31 @@ fn test_pqr() { (ebpf::UDIV64_IMM, 13u64, 4u64, 3u64), (ebpf::UREM32_IMM, 13u64, 4u64, 1u64), (ebpf::UREM64_IMM, 13u64, 4u64, 1u64), - (ebpf::UHMUL64_IMM, 13u64, u64::MAX, 12u64), - (ebpf::UDIV32_IMM, 13u64, u64::MAX, 0u64), - (ebpf::UDIV64_IMM, 13u64, u64::MAX, 0u64), - (ebpf::UREM32_IMM, 13u64, u64::MAX, 13u64), - (ebpf::UREM64_IMM, 13u64, u64::MAX, 13u64), + (ebpf::UHMUL64_IMM, 13u64, u32::MAX as u64, 0u64), + (ebpf::UDIV32_IMM, 13u64, u32::MAX as u64, 0u64), + (ebpf::UDIV64_IMM, 13u64, u32::MAX as u64, 0u64), + (ebpf::UREM32_IMM, 13u64, u32::MAX as u64, 13u64), + (ebpf::UREM64_IMM, 13u64, u32::MAX as u64, 13u64), (ebpf::UHMUL64_IMM, u64::MAX, 4u64, 3u64), (ebpf::UDIV32_IMM, u64::MAX, 4u64, (u32::MAX / 4) as u64), (ebpf::UDIV64_IMM, u64::MAX, 4u64, u64::MAX / 4), (ebpf::UREM32_IMM, u64::MAX, 4u64, 3u64), (ebpf::UREM64_IMM, u64::MAX, 4u64, 3u64), - (ebpf::UHMUL64_IMM, u64::MAX, u64::MAX, u64::MAX - 1), - (ebpf::UDIV32_IMM, u64::MAX, u64::MAX, 1u64), - (ebpf::UDIV64_IMM, u64::MAX, u64::MAX, 1u64), - (ebpf::UREM32_IMM, u64::MAX, u64::MAX, 0u64), - (ebpf::UREM64_IMM, u64::MAX, u64::MAX, 0u64), + ( + ebpf::UHMUL64_IMM, + u64::MAX, + u32::MAX as u64, + u32::MAX as u64 - 1, + ), + (ebpf::UDIV32_IMM, u64::MAX, u32::MAX as u64, 1u64), + ( + ebpf::UDIV64_IMM, + u64::MAX, + u32::MAX as u64, + u32::MAX as u64 + 2, + ), + (ebpf::UREM32_IMM, u64::MAX, u32::MAX as u64, 0u64), + (ebpf::UREM64_IMM, u64::MAX, u32::MAX as u64, 0u64), ( ebpf::LMUL32_IMM, 13i64 as u64,