Add offset validation and remove unnecessary code per code review

ethereum-optimism · Oct 22, 2024 · 22f0c71 · 22f0c71
1 parent 4f9d2ce
commit 22f0c71
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Showing 5 changed files with 12 additions and 19 deletions.
diff --git a/rvgo/fast/instrumented.go b/rvgo/fast/instrumented.go
@@ -83,6 +83,9 @@ func (m *InstrumentedState) readPreimage(key [32]byte, offset uint64) (dat [32]b
 		m.lastPreimage = preimage
 	}
 	m.lastPreimageOffset = offset
+	if offset >= uint64(len(preimage)) {
+		panic("Preimage offset out-of-bounds")
+	}
 	datLen = uint64(copy(dat[:], preimage[offset:]))
 	return
 }

diff --git a/rvgo/fast/memory.go b/rvgo/fast/memory.go
@@ -195,10 +195,7 @@ func (m *Memory) SetAligned(addr uint64, dat []byte) {
 		m.Invalidate(addr) // invalidate this branch of memory, now that the value changed
 	}
 
-	d := copy(p.Data[pageAddr:], dat)
-	if d == len(dat) {
-		return // if all the data fitted in the page, we're done
-	}
+	copy(p.Data[pageAddr:], dat)
 }
 
 func (m *Memory) GetUnaligned(addr uint64, dest []byte) {

diff --git a/rvgo/fast/vm.go b/rvgo/fast/vm.go
@@ -266,10 +266,6 @@ func (inst *InstrumentedState) riscvStep() (outErr error) {
 		s.Memory.SetAligned(rightAddr, bytez[leftSize:size])
 	}
 
-	//
-	// CSR (control and status registers) functions
-	//
-
 	//
 	// Preimage oracle interactions
 	//
@@ -378,7 +374,7 @@ func (inst *InstrumentedState) riscvStep() (outErr error) {
 			// ensure MAP_ANONYMOUS is set and fd == -1
 			if (flags&0x20) == 0 || fd != u64Mask() {
 				addr = u64Mask()
-				errCode = toU64(0x4d) // no error
+				errCode = toU64(0x4d) // EBADF
 			} else {
 				// ignore: prot, flags, fd, offset
 				switch addr {

diff --git a/rvgo/slow/vm.go b/rvgo/slow/vm.go
@@ -128,7 +128,13 @@ func Step(calldata []byte, po PreimageOracle) (stateHash common.Hash, outErr err
 	}
 
 	proofContentOffset := shortToU64(uint16(stateContentOffset) + paddedStateSize + 32)
-	// TODO: validate abi offset values?
+
+	if and(b32asBEWord(calldataload(shortToU64(uint16(stateContentOffset)+paddedStateSize))), shortToU256(60-1)) != (U256{}) {
+		// proof offset must be stateContentOffset+paddedStateSize+32
+		// proof size: 64-5+1=60 * 32 byte leaf,
+		// but multiple memProof can be used, so the proofSize must be a multiple of 60
+		panic("invalid proof offset input")
+	}
 
 	//
 	// State loading
@@ -450,10 +456,6 @@ func Step(calldata []byte, po PreimageOracle) (stateHash common.Hash, outErr err
 		storeMemUnaligned(addr, size, u64ToU256(value), proofIndexL, proofIndexR)
 	}
 
-	//
-	// CSR (control and status registers) functions
-	//
-
 	//
 	// Preimage oracle interactions
 	//

diff --git a/rvsol/src/RISCV.sol b/rvsol/src/RISCV.sol
@@ -333,7 +333,6 @@ contract RISCV {
                 out := 548
             }
             if iszero(eq(proof.offset, proofContentOffset())) { revert(0, 0) }
-            // TODO: validate abi offset values?
 
             //
             // State loading
@@ -728,10 +727,6 @@ contract RISCV {
                 storeMemUnaligned(addr, size, u64ToU256(value), proofIndexL, proofIndexR)
             }
 
-            //
-            // CSR (control and status registers) functions
-            //
-
             //
             // Preimage oracle interactions
             //