From 4658c4c6ca40290d7a796d4bdd2d5f94450c00a2 Mon Sep 17 00:00:00 2001
From: ghidra1 <ghidra1@users.noreply.github.com>
Date: Mon, 8 Jul 2024 18:57:31 -0400
Subject: [PATCH] GP-4758 Corrected ELF X86-64 GOT allocation bug.  Added a few
 relocation types.

---
 .../X86_64_ElfRelocationContext.java          | 11 +++++++-
 .../X86_64_ElfRelocationHandler.java          | 28 ++++++++++++++++++-
 2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/Ghidra/Processors/x86/src/main/java/ghidra/app/util/bin/format/elf/relocation/X86_64_ElfRelocationContext.java b/Ghidra/Processors/x86/src/main/java/ghidra/app/util/bin/format/elf/relocation/X86_64_ElfRelocationContext.java
index eae466cde5..b93435c7df 100644
--- a/Ghidra/Processors/x86/src/main/java/ghidra/app/util/bin/format/elf/relocation/X86_64_ElfRelocationContext.java
+++ b/Ghidra/Processors/x86/src/main/java/ghidra/app/util/bin/format/elf/relocation/X86_64_ElfRelocationContext.java
@@ -141,6 +141,13 @@ class X86_64_ElfRelocationContext extends ElfRelocationContext<X86_64_ElfRelocat
 
 	private Address allocateGot() {
 
+		if (allocatedGotAddress != null) {
+			if (allocatedGotAddress == Address.NO_ADDRESS) {
+				return null;
+			}
+			return allocatedGotAddress;
+		}
+
 		allocatedGotAddress = Address.NO_ADDRESS;
 		nextAllocatedGotEntryAddress = Address.NO_ADDRESS;
 
@@ -193,7 +200,9 @@ class X86_64_ElfRelocationContext extends ElfRelocationContext<X86_64_ElfRelocat
 	 */
 	private Address getNextAllocatedGotEntryAddress() {
 		if (nextAllocatedGotEntryAddress == null) {
-			allocateGot();
+			if (allocateGot() == null) {
+				return Address.NO_ADDRESS; // failed to allocate got
+			}
 		}
 
 		Address addr = nextAllocatedGotEntryAddress;
diff --git a/Ghidra/Processors/x86/src/main/java/ghidra/app/util/bin/format/elf/relocation/X86_64_ElfRelocationHandler.java b/Ghidra/Processors/x86/src/main/java/ghidra/app/util/bin/format/elf/relocation/X86_64_ElfRelocationHandler.java
index f7a0809bb1..20be2c3716 100644
--- a/Ghidra/Processors/x86/src/main/java/ghidra/app/util/bin/format/elf/relocation/X86_64_ElfRelocationHandler.java
+++ b/Ghidra/Processors/x86/src/main/java/ghidra/app/util/bin/format/elf/relocation/X86_64_ElfRelocationHandler.java
@@ -134,7 +134,7 @@ public class X86_64_ElfRelocationHandler extends
 				}
 				catch (NotFoundException e) {
 					markAsError(program, relocationAddress, type, symbolName, symbolIndex,
-						e.getMessage(), elfRelocationContext.getLog());
+						"GOT allocation failure", elfRelocationContext.getLog());
 					return RelocationResult.FAILURE;
 				}
 				break;
@@ -257,6 +257,32 @@ public class X86_64_ElfRelocationHandler extends
 				}
 				value = symbolGotAddress.getOffset() + addend - offset;
 				memory.setLong(relocationAddress, value);
+				break;
+
+			case R_X86_64_GOT64:  // 64 bit GOT entry offset (UNVERIFIED)
+				symbolGotAddress = elfRelocationContext.getGotEntryAddress(sym);
+				if (symbolGotAddress == null) {
+					markAsError(program, relocationAddress, type, symbolName, symbolIndex,
+						"GOT allocation failure", elfRelocationContext.getLog());
+					return RelocationResult.FAILURE;
+				}
+				value = symbolGotAddress.getOffset() + addend;
+				memory.setLong(relocationAddress, value);
+				break;
+
+			case R_X86_64_PLTOFF64: // 64 bit GOT relative offset to PLT entry (UNVERIFIED)
+				long dotgot;
+				try {
+					dotgot = elfRelocationContext.getGOTValue();
+				}
+				catch (NotFoundException e) {
+					markAsError(program, relocationAddress, type, symbolName, symbolIndex,
+						"GOT allocation failure", elfRelocationContext.getLog());
+					return RelocationResult.FAILURE;
+				}
+				value = symbolValue - dotgot + addend;
+				memory.setLong(relocationAddress, value);
+				break;
 
 			case R_X86_64_RELATIVE:
 				// word64 for LP64 and specifies word32 for ILP32,