[PATCH] D14451: [ELF2] - Fixed crash for case when section sh_entsize is set to zero for SHF_MERGE type of sections.

[Rafael Espíndola via llvm-commits]

LGTM

On 6 November 2015 at 12:01, George Rimar <grimar at accesssoftek.com> wrote:
> grimar created this revision.
> grimar added reviewers: ruiu, rafael.
> grimar added subscribers: llvm-commits, grimar.
>
> Fixed crash for incorrect elf input, bfd does not crash btw.
>
> http://reviews.llvm.org/D14451
>
> Files:
>   ELF/InputFiles.cpp
>   test/elf2/Inputs/invalid-shentsize-zero.elf
>   test/elf2/invalid-elf.test
>
> Index: test/elf2/invalid-elf.test
> ===================================================================
> --- test/elf2/invalid-elf.test
> +++ test/elf2/invalid-elf.test
> @@ -23,4 +23,8 @@
>  # RUN: not ld.lld2 %p/Inputs/invalid-shstrndx.so -o %t2 2>&1 | \
>  # RUN:   FileCheck --check-prefix=INVALID-SECTION-INDEX %s
>
> +# RUN: not ld.lld2 %p/Inputs/invalid-shentsize-zero.elf -o %t2 2>&1 | \
> +# RUN:   FileCheck --check-prefix=INVALID-SHENTSIZE-ZERO %s
> +# INVALID-SHENTSIZE-ZERO: SHF_MERGE section size must be a multiple of sh_entsize
> +
>  .long foo
> Index: ELF/InputFiles.cpp
> ===================================================================
> --- ELF/InputFiles.cpp
> +++ ELF/InputFiles.cpp
> @@ -143,7 +143,7 @@
>    if (Flags & SHF_WRITE)
>      error("Writable SHF_MERGE sections are not supported");
>    uintX_t EntSize = Sec.sh_entsize;
> -  if (Sec.sh_size % EntSize)
> +  if (!EntSize || Sec.sh_size % EntSize)
>      error("SHF_MERGE section size must be a multiple of sh_entsize");
>
>    // Don't try to merge if the aligment is larger than the sh_entsize.
>
>