| commit | b7eeaf878bcb9ef63dbbaf5a076271d204aeb875 | [log] [tgz] |
|---|---|---|
| author | Fangrui Song <maskray@google.com> | Fri Sep 20 15:03:21 2019 +0000 |
| committer | Fangrui Song <maskray@google.com> | Fri Sep 20 15:03:21 2019 +0000 |
| tree | b3cd638683dde9da7e5ab5e1ade304cd7956d2c2 | |
| parent | 1f1de38b0686fc0793d5c7afac9e99e05b4c5c3e [diff] |
[ELF] Error if the linked-to section of a SHF_LINK_ORDER section is discarded
Summary:
If st_link(A)=B, and A has the SHF_LINK_ORDER flag, we may dereference
a null pointer if B is garbage collected (PR43147):
1. In Wrter.cpp:compareByFilePosition, `aOut->sectionIndex` or `bOut->sectionIndex`
2. In OutputSections::finalize, `d->getParent()->sectionIndex`
Simply error and bail out to avoid null pointer dereferences. ld.bfd has
a similar error:
sh_link of section `.bar' points to discarded section `.foo0' of `a.o'
ld.bfd is more permissive in that it just checks whether the linked-to
section of the first input section is discarded. This is likely because
it sets sh_link of the output section according to the first input
section.
Reviewed By: grimar
Differential Revision: https://reviews.llvm.org/D67761
git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@372400 91177308-0d34-0410-b5e6-96231b3b80d8
This directory and its subdirectories contain source code for the LLVM Linker, a modular cross platform linker which is built as part of the LLVM compiler infrastructure project.
lld is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt.
In order to make sure various developers can evaluate patches over the same tests, we create a collection of self contained programs.
It is hosted at https://s3-us-west-2.amazonaws.com/linker-tests/lld-speed-test.tar.xz
The current sha256 is 10eec685463d5a8bbf08d77f4ca96282161d396c65bd97dc99dbde644a31610f.