This has two advantages:
1) We slowly move away from ErrorOr to the new handling interface,
in the hope of having an uniform error handling in LLVM, eventually.
2) We're starting to have *meaningful* error messages for invalid
object ELF files, rather than a generic "parse error". At some point
we should include also the offset to improve the quality of the
diagnostic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287081 91177308-0d34-0410-b5e6-96231b3b80d8
All error checking now happens when the information is needed. The
only thing left is the minimum size of the buffer and that can be just
a precondition. I will add an ErrorOr create method in a followup
commit.
Also don't store a pointer to the Header, since it is just a trivial
cast.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285961 91177308-0d34-0410-b5e6-96231b3b80d8
This adds versions of getSectionIndex, getSection and getSymbol that
instead of a Elf_Shdr take the content of that section.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285932 91177308-0d34-0410-b5e6-96231b3b80d8
This saves a field that is not always used. It also avoids failing a
program that doesn't need the section names.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285753 91177308-0d34-0410-b5e6-96231b3b80d8
The description in the ELF spec is just
---------------------------
If the section name string table section index is greater than or
equal to SHN_LORESERVE (0xff00), this member has the value SHN_XINDEX
(0xffff) and the actual index of the section name string table section
is contained in the sh_link field of the section header at index 0.
---------------------------
So we only have to check for it being SHN_XINDEX. Also, sh_link is
always 32 bits, so don't return an uintX_t.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285747 91177308-0d34-0410-b5e6-96231b3b80d8
with fix: edited invalid-section-index2.elf input to pass the new check and
fail on the same place it was intended to fail.
Original commit message:
Elf.h already has code checking that section table does not go past end of file.
Problem is that this check may not work on values greater than UINT64_MAX / Header->e_shentsize
because of calculation overflow.
Parch fixes the issue.
Differential revision: https://reviews.llvm.org/D25432
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285586 91177308-0d34-0410-b5e6-96231b3b80d8
Elf.h already has code checking that section table does not go past end of file.
Problem is that this check may not work on values greater than UINT64_MAX / Header->e_shentsize
because of calculation overflow.
Parch fixes the issue.
Differential revision: https://reviews.llvm.org/D25432
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@285285 91177308-0d34-0410-b5e6-96231b3b80d8
Without this check LLD crashes when SHT_GROUP section has invalid symbol index
because of next code:
template <class ELFT>
StringRef elf::ObjectFile<ELFT>::getShtGroupSignature(const Elf_Shdr &Sec) {
..
const Elf_Sym *Sym = Obj.getSymbol(Symtab, Sec.sh_info);
..
}
If sh_info is too large, &Symbols[Index] just asserts.
No testcases provided because llvm-objdump/llvm-readelf does
not use getSymbol() function.
I`ll commit testcase for LLD separatelly.
Differential revision: https://reviews.llvm.org/D25516
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284702 91177308-0d34-0410-b5e6-96231b3b80d8
With fix: hex edited the precompiled inputs from another testcases to pass new checks.
Original commit message:
[Object/ELF] - Check that e_shnum is null when e_shoff is.
Spec says (http://www.sco.com/developers/gabi/1998-04-29/ch4.eheader.html) :
e_shnum
This member holds the number of entries in the section header table. Thus the product of e_shentsize and e_shnum gives the section header table's size in bytes. If a file has no section header table, e_shnum holds the value zero.
Revealed using "id_000037,sig_11,src_000015,op_havoc,rep_8" from PR30540
That was the reason of crash in lld on incorrect input file.
Binary reduced using afl-min.
Differential revision: https://reviews.llvm.org/D25090
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284374 91177308-0d34-0410-b5e6-96231b3b80d8
Spec says (http://www.sco.com/developers/gabi/1998-04-29/ch4.eheader.html) :
e_shnum
This member holds the number of entries in the section header table. Thus the product of e_shentsize and e_shnum gives the section header table's size in bytes. If a file has no section header table, e_shnum holds the value zero.
Revealed using "id_000037,sig_11,src_000015,op_havoc,rep_8" from PR30540
That was the reason of crash in lld on incorrect input file.
Binary reduced using afl-min.
Differential revision: https://reviews.llvm.org/D25090
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284371 91177308-0d34-0410-b5e6-96231b3b80d8
If object has wrong (large) string table index and
also incorrect large value for amount of sections in total,
then section index passes the check:
if (Index >= getNumSections())
return object_error::invalid_section_index;
But result pointer then is far after end of file data, what
result in a crash.
Differential revision: https://reviews.llvm.org/D25081
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284369 91177308-0d34-0410-b5e6-96231b3b80d8
Bot does not like it: http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/17075
/mnt/b/sanitizer-buildbot3/sanitizer-x86_64-linux-fast/build/llvm/test/Object/invalid.test:70:32: error: expected string not found in input
INVALID-SEC-ADDRESS-ALIGNMENT: Invalid address alignment of section headers
^
<stdin>:1:1: note: scanning from here
/mnt/b/sanitizer-buildbot3/sanitizer-x86_64-linux-fast/build/llvm/include/llvm/Object/ELF.h:412:7: runtime error: upcast of misaligned address 0x000002d8b899 for type 'llvm::object::Elf_Shdr_Impl<llvm::object::ELFType<llvm::support::endianness::little, true> >', which requires 2 byte alignment
^
<stdin>:1:125: note: possible intended match here
/mnt/b/sanitizer-buildbot3/sanitizer-x86_64-linux-fast/build/llvm/include/llvm/Object/ELF.h:412:7: runtime error: upcast of misaligned address 0x000002d8b899 for type 'llvm::object::Elf_Shdr_Impl<llvm::object::ELFType<llvm::support::endianness::little, true> >', which requires 2 byte alignment
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283858 91177308-0d34-0410-b5e6-96231b3b80d8
sections_begin() may return unalignment pointer when Header->e_shoff isinvalid.
That may result in a crash in clients, for example we have one in LLD:
assert((PtrWord & ~PointerBitMask) == 0 &&
"Pointer is not sufficiently aligned");
fails when trying to push_back Elf_Shdr* (unaligned) into TinyPtrVector.
Patch forces check for alignment of Header->e_shoff.
Differential revision: https://reviews.llvm.org/D25368
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283740 91177308-0d34-0410-b5e6-96231b3b80d8
