Summary:
Add the ability to suppress UBSan reports for files/functions/modules
at runtime. The user can now pass UBSAN_OPTIONS=suppressions=supp.txt
with the contents of the form:
signed-integer-overflow:file-with-known-overflow.cpp
alignment:function_doing_unaligned_access
vptr:shared_object_with_vptr_failures.so
Suppression categories match the arguments passed to -fsanitize=
flag (although, see below). There is no overhead if suppressions are
not provided. Otherwise there is extra overhead for symbolization.
Limitations:
1) sometimes suppressions need debug info / symbol table to function
properly (although sometimes frontend generates enough info to
do the match).
2) it's only possible to suppress recoverable UB kinds - if you've
built the code with -fno-sanitize-recover=undefined, suppressions
will not work.
3) categories are fine-grained check kinds, not groups like "undefined"
or "integer", so you can't write "undefined:file_with_ub.cc".
Reviewers: rsmith, kcc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D15363
llvm-svn: 256018
Let unrecoverable handlers be responsbile for killing the
program with Die(), and let functions which print the error
report know if it's going to happen. Re-write the comments to
describe the situation.
llvm-svn: 255081
Currently, this is an NFC. However, knowing out the kind of error
report before we bring up all the reporting machinery (implemented in
ScopedReport class) is important once we teach UBSan runtime
suppressions.
llvm-svn: 255074
This reverts commit r250823.
Replacing at least some of empty
constructors with "= default" variants is a semantical change which we
don't want. E.g. __tsan::ClockBlock contains a union of large arrays,
and it's critical for correctness and performance that we don't memset()
these arrays in the constructor.
llvm-svn: 251717
Specifically:
- Start using %expect_crash.
- Provide an implementation of __ubsan::getDynamicTypeInfoFromVtable
for the Microsoft C++ ABI. This is all that is needed for CFI
diagnostics; UBSan's -fsanitize=vptr also requires an implementation of
__ubsan::checkDynamicType.
- Build the sanitizer runtimes against the release version of the C
runtime, even in debug builds.
- Accommodate demangling differences in tests.
Differential Revision: http://reviews.llvm.org/D11029
llvm-svn: 241745
SuppressionContext is no longer a singleton, shared by all sanitizers,
but a regular class. Each of ASan, LSan, UBSan and TSan now have their
own SuppressionContext, which only parses suppressions specific to
that sanitizer.
"suppressions" flag is moved away from common flags into tool-specific
flags, so the user now may pass
ASAN_OPTIONS=suppressions=asan_supp.txt LSAN_OPIONS=suppressions=lsan_supp.txt
in a single invocation.
llvm-svn: 230026
Summary:
__ubsan::getFunctionLocation() used to issue a call to symbolizer, and
convert the result (SymbolizedStack) to one of UBSan structures:
SourceLocation, ModuleLocation or MemoryLocation. This:
(1) is inefficient: we do an extra allocation/deallocation to copy data,
while we can instead can just pass SymbolizedStack around (which
contains all the necessary data).
(2) leaks memory: strings stored in SourceLocation/MemoryLocation are
never deallocated, and Filipe Cabecinhas suggests this causes crashes
of UBSan-ified programs in the wild.
Instead, let Location store a pointer to SymbolizedStack object, and
make sure it's properly deallocated when UBSan handler exits.
ModuleLocation is made obsolete by this change, and is deleted.
Test Plan: check-ubsan test suite
Reviewers: rsmith, filcab
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D7548
llvm-svn: 228869
getCallerLocation() is expensive as it issues a call to symbolizer.
(In fact, this function has a memory leak at the moment, but this
will be fixed in the nearest future). We should only call it if
we're actually going to print an error report, in particular,
once for every reported source location.
__ubsan_handle_type_mismatch: call getCallerLocation() only if
provided source location is invalid, and only if the report is not
deduplicated.
__ubsan_handle_float_cast_overflow: call getSourceLocation with
correct CallerPC (the one in user code, not in UBSan handler). Source
location for this check is not currently emitted by frontend.
llvm-svn: 228732
By default summary is not printed if UBSan is run in a standalone mode,
but is printed if it's combined with another sanitizer (like ASan).
llvm-svn: 218135
This object is used to encapsulate all actions that need to be
done before/after printing UBSan diagnostics. Currently these
actions are:
* locking a mutex to ensure that UBSan diagnostics from several
threads won't mix with each other and with other sanitizers'
reports
* killing a program once the report is printed (if necessary).
Use this object in all UBSan handlers. Unify the way we implement
fatal and non-fatal handlers by making all the handlers simple
one-liners that redirect __ubsan_handle_foo(_abort)? to
handleFooImpl().
llvm-svn: 214279
This will ensure that stack frames in error reports will not
contain internal UBSan failures, and frame #0 will be the
actual place in the program where the error happens.
llvm-svn: 214245
This change introduces the first UBSan-specific runtime flag: print_stacktrace
(off by default). It can be set in UBSAN_OPTIONS to unwind and print call stacks
in addition to diagnostic messages. For now these stacks are printed only
in vptr checker.
This change is based on http://reviews.llvm.org/D4410 by Byoungyoung Lee!
llvm-svn: 213783
pointing at the bad location and a snippet of nearby memory values. This is
strictly best-effort; reading these bytes to display the note could lead to a
seg fault, and that's explicitly OK.
llvm-svn: 170415
one out from the return address. Currently, we can only resolve this address to
a file and line number if we have an external symbolizer.
llvm-svn: 170407