Commit Graph

7 Commits

Author SHA1 Message Date
Duncan P. N. Exon Smith fb49491477 IR: Update clang for Metadata/Value split in r223802
Match LLVM API changes from r223802.

llvm-svn: 223803
2014-12-09 18:39:32 +00:00
Alexey Samsonov edf99a92c0 Introduce a SanitizerKind enum to LangOptions.
Use the bitmask to store the set of enabled sanitizers instead of a
bitfield. On the negative side, it makes syntax for querying the
set of enabled sanitizers a bit more clunky. On the positive side, we
will be able to use SanitizerKind to eventually implement the
new semantics for -fsanitize-recover= flag, that would allow us
to make some sanitizers recoverable, and some non-recoverable.

No functionality change.

llvm-svn: 221558
2014-11-07 22:29:38 +00:00
Alexey Samsonov a0ac3c2bf0 [ASan] Improve blacklisting of global variables.
This commit changes the way we blacklist global variables in ASan.
Now the global is excluded from instrumentation (either regular
bounds checking, or initialization-order checking) if:

1) Global is explicitly blacklisted by its mangled name.
This part is left unchanged.

2) SourceLocation of a global is in blacklisted source file.
This changes the old behavior, where instead of looking at the
SourceLocation of a variable we simply considered llvm::Module
identifier. This was wrong, as identifier may not correspond to
the file name, and we incorrectly disabled instrumentation
for globals coming from #include'd files.

3) Global is blacklisted by type.
Now we build the type of a global variable using Clang machinery
(QualType::getAsString()), instead of llvm::StructType::getName().

After this commit, the active users of ASan blacklist files
may have to revisit them (this is a backwards-incompatible change).

llvm-svn: 220097
2014-10-17 22:37:33 +00:00
Alexey Samsonov 1444bb9fc8 SanitizerBlacklist: blacklist functions by their source location.
This commit changes the way we blacklist functions in ASan, TSan,
MSan and UBSan. We used to treat function as "blacklisted"
and turned off instrumentation in it in two cases:

1) Function is explicitly blacklisted by its mangled name.
This part is not changed.

2) Function is located in llvm::Module, whose identifier is
contained in the list of blacklisted sources. This is completely
wrong, as llvm::Module may not correspond to the actual source
file function is defined in. Also, function can be defined in
a header, in which case user had to blacklist the .cpp file
this header was #include'd into, not the header itself.
Such functions could cause other problems - for instance, if the
header was included in multiple source files, compiled
separately and linked into a single executable, we could end up
with both instrumented and non-instrumented version of the same
function participating in the same link.

After this change we will make blacklisting decision based on
the SourceLocation of a function definition. If a function is
not explicitly defined in the source file, (for example, the
function is compiler-generated and responsible for
initialization/destruction of a global variable), then it will
be blacklisted if the corresponding global variable is defined
in blacklisted source file, and will be instrumented otherwise.

After this commit, the active users of blacklist files may have
to revisit them. This is a backwards-incompatible change, but
I don't think it's possible or makes sense to support the
old incorrect behavior.

I plan to make similar change for blacklisting GlobalVariables
(which is ASan-specific).

llvm-svn: 219997
2014-10-17 00:20:19 +00:00
Kostya Serebryany 4ee6904288 [clang/asan] call __asan_poison_cxx_array_cookie after operator new[]
Summary:
PR19838
When operator new[] is called and an array cookie is created
we want asan to detect buffer overflow bugs that touch the cookie.
For that we need to
  a) poison the shadow for the array cookie (call __asan_poison_cxx_array_cookie).
  b) ignore the legal accesses to the cookie generated by clang (add 'nosanitize' metadata)

Reviewers: timurrrr, samsonov, rsmith

Reviewed By: rsmith

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D4774

llvm-svn: 216434
2014-08-26 02:29:59 +00:00
Alexey Samsonov d9ad5cec0c [ASan] Use metadata to pass source-level information from Clang to ASan.
Instead of creating global variables for source locations and global names,
just create metadata nodes and strings. They will be transformed into actual
globals in the instrumentation pass (if necessary). This approach is more
flexible:
1) we don't have to ensure that our custom globals survive all the optimizations
2) if globals are discarded for some reason, we will simply ignore metadata for them
   and won't have to erase corresponding globals
3) metadata for source locations can be reused for other purposes: e.g. we may
   attach source location metadata to alloca instructions and provide better descriptions
   for stack variables in ASan error reports.

No functionality change.

llvm-svn: 214604
2014-08-02 00:35:50 +00:00
Alexey Samsonov 4b8de11c81 [Sanitizer] Introduce SanitizerMetadata class.
It is responsible for generating metadata consumed by sanitizer instrumentation
passes in the backend. Move several methods from CodeGenModule to SanitizerMetadata.
For now the class is stateless, but soon it won't be the case.

Instead of creating globals providing source-level information to ASan, we will create
metadata nodes/strings which will be turned into actual global variables in the
backend (if needed).

No functionality change.

llvm-svn: 214564
2014-08-01 21:35:28 +00:00