diff --git a/Ghidra/Framework/Emulation/src/main/java/ghidra/pcode/exec/PcodeExecutor.java b/Ghidra/Framework/Emulation/src/main/java/ghidra/pcode/exec/PcodeExecutor.java index 59fd138f44..bdfe6f07ad 100644 --- a/Ghidra/Framework/Emulation/src/main/java/ghidra/pcode/exec/PcodeExecutor.java +++ b/Ghidra/Framework/Emulation/src/main/java/ghidra/pcode/exec/PcodeExecutor.java @@ -474,7 +474,7 @@ public class PcodeExecutor { } else { branchToOffset(op, target.getOffset(), frame); - branchToAddress(op, target); + branchToAddress(op, checkInjectedTarget(target)); } } @@ -530,6 +530,28 @@ public class PcodeExecutor { return op.getInput(0); } + /** + * Check and correct the given target address, if it resides in "NO ADDRESS" space. + * + *

+ * At some point, we made a change to set the "target address" of compiled p-code userops to + * {@link Address#NO_ADDRESS} instead of pretending its at {@code ram:00000000}. This is + * philosophically cleaner, but leads to a practical issue in that the p-code compiler sets the + * target address of any branch to be in the same space, which for injects, will wind up in "NO + * ADDRESS." I don't know the use case for having target addresses anywhere but default space, + * so I'll maintain that behavior, but if it ever lands in "NO ADDRESS," we're going to assume + * it was an inject, and that the intended target was the default space. + * + * @param target the proposed target address + * @return the same or corrected target address + */ + protected Address checkInjectedTarget(Address target) { + if (target.getAddressSpace() != Address.NO_ADDRESS.getAddressSpace()) { + return target; + } + return language.getDefaultSpace().getAddress(target.getOffset()); + } + /** * Perform the actual logic of an indirect branch p-code op * @@ -548,7 +570,7 @@ public class PcodeExecutor { long concrete = arithmetic.toLong(offset, Purpose.BRANCH); Address target = op.getSeqnum().getTarget().getNewAddress(concrete, true); - branchToAddress(op, target); + branchToAddress(op, checkInjectedTarget(target)); } /** @@ -576,7 +598,7 @@ public class PcodeExecutor { public void executeCall(PcodeOp op, PcodeFrame frame, PcodeUseropLibrary library) { Address target = getBranchTarget(op); branchToOffset(op, target.getOffset(), frame); - branchToAddress(op, target); + branchToAddress(op, checkInjectedTarget(target)); } /** diff --git a/Ghidra/Framework/Emulation/src/test/java/ghidra/pcode/emu/jit/AbstractPcodeEmulatorTest.java b/Ghidra/Framework/Emulation/src/test/java/ghidra/pcode/emu/jit/AbstractPcodeEmulatorTest.java index 5d9f8b10a4..607f49f99c 100644 --- a/Ghidra/Framework/Emulation/src/test/java/ghidra/pcode/emu/jit/AbstractPcodeEmulatorTest.java +++ b/Ghidra/Framework/Emulation/src/test/java/ghidra/pcode/emu/jit/AbstractPcodeEmulatorTest.java @@ -298,4 +298,75 @@ public abstract class AbstractPcodeEmulatorTest extends AbstractGTest { arithmetic.toLong(thread.getState().getVar(r1, Reason.INSPECT), Purpose.INSPECT)); assertEquals(inject, thread.getCounter()); } + + @Test + public void testInjectedBranch() throws Exception { + PcodeEmulator emu = createEmulator(getLanguage(LANGID_TOY_BE)); + PcodeArithmetic arithmetic = emu.getArithmetic(); + AddressSpace space = emu.getLanguage().getDefaultSpace(); + AssemblyBuffer asm = new AssemblyBuffer(Assemblers.getAssembler(emu.getLanguage()), + space.getAddress(0x00400000)); + + asm.assemble("imm r1, #1"); + Address inject = asm.getNext(); + asm.assemble("add r1, #1"); + Address target = asm.getNext(); + + byte[] bytes = asm.getBytes(); + emu.getSharedState().setVar(asm.getEntry(), bytes.length, false, bytes); + PcodeThread thread = emu.newThread(); + thread.overrideCounter(asm.getEntry()); + + emu.inject(inject, "goto 0x%08x;".formatted(target.getOffset())); + + try { + thread.run(); + fail("Should have crashed on decode error"); + } + catch (DecodePcodeExecutionException e) { + // Space assertion is subsumed by counter assertion + } + + Register r1 = emu.getLanguage().getRegister("r1"); + assertEquals(1, + arithmetic.toLong(thread.getState().getVar(r1, Reason.INSPECT), Purpose.INSPECT)); + assertEquals(target, thread.getCounter()); + } + + @Test + public void testInjectedIndirectBranch() throws Exception { + PcodeEmulator emu = createEmulator(getLanguage(LANGID_TOY_BE)); + PcodeArithmetic arithmetic = emu.getArithmetic(); + AddressSpace space = emu.getLanguage().getDefaultSpace(); + AssemblyBuffer asm = new AssemblyBuffer(Assemblers.getAssembler(emu.getLanguage()), + space.getAddress(0x00400000)); + + asm.assemble("imm r1, #1"); + Address inject = asm.getNext(); + asm.assemble("add r1, #1"); + Address target = asm.getNext(); + + byte[] bytes = asm.getBytes(); + emu.getSharedState().setVar(asm.getEntry(), bytes.length, false, bytes); + PcodeThread thread = emu.newThread(); + thread.overrideCounter(asm.getEntry()); + + emu.inject(inject, """ + r2 = 0x%08x; + goto [r2]; + """.formatted(target.getOffset())); + + try { + thread.run(); + fail("Should have crashed on decode error"); + } + catch (DecodePcodeExecutionException e) { + // Space assertion is subsumed by counter assertion + } + + Register r1 = emu.getLanguage().getRegister("r1"); + assertEquals(1, + arithmetic.toLong(thread.getState().getVar(r1, Reason.INSPECT), Purpose.INSPECT)); + assertEquals(target, thread.getCounter()); + } }