[ELF] - Do not hang if broken object has option descriptor in .MIPS.options with size of zero.

Previously lld would hang in infinite loop in this case,
patch fixes the issue. Object was found during AFL run.

Differential revision: https://reviews.llvm.org/D25229

llvm-svn: 283208

3 files changed, 7 insertions, 0 deletions

diff --git a/lld/ELF/InputSection.cpp b/lld/ELF/InputSection.cpp
index 3341a799f6e..8137b16035d 100644
--- a/lld/ELF/InputSection.cpp
+++ b/lld/ELF/InputSection.cpp
@@ -694,6 +694,8 @@ MipsOptionsInputSection<ELFT>::MipsOptionsInputSection(elf::ObjectFile<ELFT> *F,
         error(getName(this) + ": unsupported non-zero ri_gp_value");
       break;
     }
+    if (!O->size)
+      fatal(getName(this) + ": zero option descriptor size");
     D = D.slice(O->size);
   }
 }
diff --git a/lld/test/ELF/invalid/Inputs/mips-invalid-options-descriptor.elf b/lld/test/ELF/invalid/Inputs/mips-invalid-options-descriptor.elf
new file mode 100644
index 00000000000..85feeebc619
--- /dev/null
+++ b/lld/test/ELF/invalid/Inputs/mips-invalid-options-descriptor.elf
diff --git a/lld/test/ELF/invalid/mips-invalid-options-descriptor.s b/lld/test/ELF/invalid/mips-invalid-options-descriptor.s
new file mode 100644
index 00000000000..2fd5bf5a513
--- /dev/null
+++ b/lld/test/ELF/invalid/mips-invalid-options-descriptor.s
@@ -0,0 +1,5 @@
+## mips-invalid-options-descriptor.elf has option descriptor in 
+## .MIPS.options with size of zero.
+# RUN: not ld.lld %p/Inputs/mips-invalid-options-descriptor.elf -o %t2 2>&1 | \
+# RUN:   FileCheck %s
+# CHECK: zero option descriptor size