wangtao
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

[ELF] Don't crash when parsing a file with external version definition references 

Summary:
We were crashing when linking telnetd in FreeBSD because lld was emitting
corrupted output files for --norosegment. In this file the version index of some symbols
was set to 9 but lld only found 8 version definitions.

I am not sure how to create a minimal .so file that also exposes this behaviour so I just added the one that initially caused the error to Inputs/

This partially addresses https://bugs.llvm.org/show_bug.cgi?id=34705

Reviewers: ruiu, rafael, pcc, grimar

Reviewed By: ruiu

Subscribers: emaste, krytarowski

Tags: #lld

Differential Revision: https://reviews.llvm.org/D38397

llvm-svn: 315035
This commit is contained in:
Alexander Richardson 2017-10-05 23:28:29 +00:00
parent b4e77d98ed
commit 57f089775b
3 changed files with 22 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
lld/ELF/InputFiles.cpp
View File

@ -775,9 +775,18 @@ template <class ELFT> void SharedFile<ELFT>::parseRest() {
// Ignore local symbols. // Ignore local symbols.
if (Versym && VersymIndex == VER_NDX_LOCAL) if (Versym && VersymIndex == VER_NDX_LOCAL)
continue; continue;
const Elf_Verdef *V = nullptr;
const Elf_Verdef *V = if (VersymIndex != VER_NDX_GLOBAL) {
VersymIndex == VER_NDX_GLOBAL ? nullptr : Verdefs[VersymIndex]; if (VersymIndex >= Verdefs.size()) {
error("corrupt input file: version definition index " +
Twine(VersymIndex) + " for symbol " + Name +
" is greater than the maximum value " +
Twine(Verdefs.size() - 1) + "\n>>> symbol is defined in " +
toString(this));
continue;
}
V = Verdefs[VersymIndex];
}
if (!Hidden) if (!Hidden)
Symtab->addShared(Name, this, Sym, V); Symtab->addShared(Name, this, Sym, V);

BIN
lld/test/ELF/Inputs/corrupt-version-reference.so Normal file
View File

Binary file not shown.

10
lld/test/ELF/corrupted-version-reference.s Normal file
View File

@ -0,0 +1,10 @@
# RUN: llvm-mc -triple=mips64-unknown-freebsd %s -filetype=obj -o %t.o
# RUN: not ld.lld %t.o %S/Inputs/corrupt-version-reference.so -o %t.exe 2>&1 | FileCheck %s
# CHECK: error: corrupt input file: version definition index 9 for symbol __cxa_finalize is greater than the maximum value 8
# CHECK: >>> symbol is defined in {{.+}}/corrupt-version-reference.so
.globl __start
__start:
dla $a0, __cxa_finalize
nop