[rpms/llvm] rawhide: Fix buffer overflow

[rpms/llvm] rawhide: Fix buffer overflow

[Tulio Magno Quites Machado Filho]

            A new commit has been pushed.

            Repo   : rpms/llvm
            Branch : rawhide
            Commit : b9b4fd0fd84a15868eb0089246ff7210d9fb0ff1
            Author : Tulio Magno Quites Machado Filho <tuliom@redhat.com>
            Date   : 2026-07-16T09:32:03-03:00
            Stats  : +92/-0 in 2 file(s)
            URL    : https://src.fedoraproject.org/rpms/llvm/c/b9b4fd0fd84a15868eb0089246ff7210d9fb0ff1?branch=rawhide

            Log:
            Fix buffer overflow

Fix an issue that could cause a buffer overflow when reading a
corrupted bitcode file.

Resolves: rhbz#2496390

---
diff --git a/0001-LLVM-Verifier-Fix-buffer-overflow-when-verifying-gc..patch b/0001-LLVM-Verifier-Fix-buffer-overflow-when-verifying-gc..patch
new file mode 100644
index 0000000..1f79e82
--- /dev/null
+++ b/0001-LLVM-Verifier-Fix-buffer-overflow-when-verifying-gc..patch
@@ -0,0 +1,88 @@
+From 7bb9626d5ab901e5c1a8e9acbbb1684c982401b4 Mon Sep 17 00:00:00 2001
+From: Tulio Magno Quites Machado Filho <tuliom@redhat.com>
+Date: Fri, 10 Jul 2026 15:45:02 -0300
+Subject: [PATCH] [LLVM][Verifier] Fix buffer overflow when verifying
+ gc.statepoint (#208278)
+
+When a negative base index is passed, the verification detects the
+out-of-bounds value and start printing information that helps to
+identify what caused the error. In order to print all the information,
+it tries to dereference the Base pointer at
+GCRelocateInst::getBasePtr(), causing the buffer overflow. Add a bounds
+check to getBasePTR() and getDerivedPtr() in order to avoid this.
+
+Improve the test in order to validate negative values passed as indexes.
+They're based on the reproducer from issue #199191.
+
+Fixes #199191
+---
+ llvm/lib/IR/AsmWriter.cpp                     | 10 ++++++++--
+ llvm/lib/IR/IntrinsicInst.cpp                 | 19 ++++++++++++++++---
+ 3 files changed, 40 insertions(+), 5 deletions(-)
+
+diff --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
+index e90630a8cae5..6752d6aa344d 100644
+--- a/llvm/lib/IR/AsmWriter.cpp
++++ b/llvm/lib/IR/AsmWriter.cpp
+@@ -4372,9 +4372,15 @@ void AssemblyWriter::printInstructionLine(const Instruction &I) {
+ /// intrinsic indicating base and derived pointer names.
+ void AssemblyWriter::printGCRelocateComment(const GCRelocateInst &Relocate) {
+   Out << " ; (";
+-  writeOperand(Relocate.getBasePtr(), false);
++  if (Value *BasePtr = Relocate.getBasePtr())
++    writeOperand(BasePtr, false);
++  else
++    Out << "invalid";
+   Out << ", ";
+-  writeOperand(Relocate.getDerivedPtr(), false);
++  if (Value *DerivedPtr = Relocate.getDerivedPtr())
++    writeOperand(DerivedPtr, false);
++  else
++    Out << "invalid";
+   Out << ")";
+ }
+ 
+diff --git a/llvm/lib/IR/IntrinsicInst.cpp b/llvm/lib/IR/IntrinsicInst.cpp
+index 3e9f3257956a..eb964d566f29 100644
+--- a/llvm/lib/IR/IntrinsicInst.cpp
++++ b/llvm/lib/IR/IntrinsicInst.cpp
+@@ -867,10 +867,16 @@ Value *GCRelocateInst::getBasePtr() const {
+   auto Statepoint = getStatepoint();
+   if (isa<UndefValue>(Statepoint))
+     return UndefValue::get(Statepoint->getType());
+-
++  // Handle too few (bundle) arguments to avoid crashes when printing invalid
++  // IR, e.g. in the verifier.
+   auto *GCInst = cast<GCStatepointInst>(Statepoint);
+-  if (auto Opt = GCInst->getOperandBundle(LLVMContext::OB_gc_live))
++  if (auto Opt = GCInst->getOperandBundle(LLVMContext::OB_gc_live)) {
++    if (getBasePtrIndex() > Opt->Inputs.size())
++      return nullptr;
+     return *(Opt->Inputs.begin() + getBasePtrIndex());
++  }
++  if (getBasePtrIndex() > GCInst->arg_size())
++    return nullptr;
+   return *(GCInst->arg_begin() + getBasePtrIndex());
+ }
+ 
+@@ -879,9 +885,16 @@ Value *GCRelocateInst::getDerivedPtr() const {
+   if (isa<UndefValue>(Statepoint))
+     return UndefValue::get(Statepoint->getType());
+ 
++  // Handle too few (bundle) arguments to avoid crashes when printing invalid
++  // IR, e.g. in the verifier.
+   auto *GCInst = cast<GCStatepointInst>(Statepoint);
+-  if (auto Opt = GCInst->getOperandBundle(LLVMContext::OB_gc_live))
++  if (auto Opt = GCInst->getOperandBundle(LLVMContext::OB_gc_live)) {
++    if (getDerivedPtrIndex() > Opt->Inputs.size())
++      return nullptr;
+     return *(Opt->Inputs.begin() + getDerivedPtrIndex());
++  }
++  if (getDerivedPtrIndex() > GCInst->arg_size())
++    return nullptr;
+   return *(GCInst->arg_begin() + getDerivedPtrIndex());
+ }
+ 
+-- 
+2.50.1
+

diff --git a/llvm.spec b/llvm.spec
index f46460a..b0a9c84 100644
--- a/llvm.spec
+++ b/llvm.spec
@@ -554,6 +554,10 @@ Patch2209: https://github.com/llvm/llvm-project/commit/0b6a1ef429.patch
 # s390x fix for unaligned memory access performance regressions.
 Patch2210: 0001-SystemZ-Avoid-unaligned-VL-VST-s-with-memcpy-memmove.patch
 
+# Fix a heap buffer overflow.
+# https://bugzilla.redhat.com/show_bug.cgi?id=2496390
+Patch2211: 0001-LLVM-Verifier-Fix-buffer-overflow-when-verifying-gc..patch
+
 #region LLD patches
 Patch106: 0001-19-Always-build-shared-libs-for-LLD.patch
 Patch2103: 0001-lld-Adjust-compressed-debug-level-test-for-s390x-wit.patch