Commit Graph

4 Commits

Author SHA1 Message Date
Fangrui Song b159906a9a [test] Change llvm-readobj -long-option to --long-option or well-known short options. NFC
Also change some options that have different semantics (cause confusion) in llvm-readelf mode:

-s => -S
-t => --symbols
-sd => --section-data

llvm-svn: 359651
2019-05-01 05:49:01 +00:00
Joel Jones a5752e199c [lld] Add REQUIRES: x86 where needed to tests
If building lld without x86 support, tests that require that support should
be treated as unsupported, not errors.

Tested using:
  1. cmake '-DLLVM_TARGETS_TO_BUILD=AArch64;X86'
     make check-lld
     =>
     Expected Passes    : 1406
     Unsupported Tests  : 287

  2. cmake '-DLLVM_TARGETS_TO_BUILD=AArch64'
     make check-lld
     =>
     Expected Passes    : 410
     Unsupported Tests  : 1283

Patch by Joel Jones

Differential Revision: https://reviews.llvm.org/D47748

llvm-svn: 334095
2018-06-06 13:56:51 +00:00
Reid Kleckner fd52096259 [LLD] Implement /guard:[no]longjmp
Summary:
This protects calls to longjmp from transferring control to arbitrary
program points. Instead, longjmp calls are limited to the set of
registered setjmp return addresses.

This also implements /guard:nolongjmp to allow users to link in object
files that call setjmp that weren't compiled with /guard:cf. In this
case, the linker will approximate the set of address taken functions,
but it will leave longjmp unprotected.

I used the following program to test, compiling it with different -guard
flags:
  $ cl -c t.c -guard:cf
  $ lld-link t.obj -guard:cf

  #include <setjmp.h>
  #include <stdio.h>
  jmp_buf buf;
  void g() {
    printf("before longjmp\n");
    fflush(stdout);
    longjmp(buf, 1);
  }
  void f() {
    if (setjmp(buf)) {
      printf("setjmp returned non-zero\n");
      return;
    }
    g();
  }
  int main() {
    f();
    printf("hello world\n");
  }

In particular, the program aborts when the code is compiled *without*
-guard:cf and linked with -guard:cf. That indicates that longjmps are
protected.

Reviewers: ruiu, inglorion, amccarth

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43217

llvm-svn: 325047
2018-02-13 20:32:53 +00:00
Reid Kleckner af2f7da74c [COFF] Add minimal support for /guard:cf
Summary:
This patch adds some initial support for Windows control flow guard. At
the end of the day, the linker needs to synthesize a table of RVAs very
similar to the structured exception handler table (/safeseh).

Both /safeseh and /guard:cf take sections of symbol table indices
(.sxdata and .gfids$y) and turn them into RVA tables referenced by the
load config struct in the CRT through special symbols.

Reviewers: ruiu, amccarth

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42592

llvm-svn: 324306
2018-02-06 01:58:26 +00:00