In r309007, I made -fsanitize=null a hard prerequisite for -fsanitize=vptr. I
did not see the need for the two checks to have separate null checking logic
for the same pointer. I expected the two checks to either always be enabled
together, or to be mutually compatible.
In the mailing list discussion re: r309007 it became clear that that isn't the
case. If a codebase is -fsanitize=vptr clean but not -fsanitize=null clean,
it's useful to have -fsanitize=vptr emit its own null check. That's what this
patch does: with it, -fsanitize=vptr can be used without -fsanitize=null.
Differential Revision: https://reviews.llvm.org/D36112
llvm-svn: 309846
The instrumentation generated by -fsanitize=vptr does not null check a
user pointer before loading from it. This causes crashes in the face of
UB member calls (this=nullptr), i.e it's causing user programs to crash
only after UBSan is turned on.
The fix is to make run-time null checking a prerequisite for enabling
-fsanitize=vptr, and to then teach UBSan to reuse these run-time null
checks to make -fsanitize=vptr safe.
Testing: check-clang, check-ubsan, a stage2 ubsan-enabled build
Differential Revision: https://reviews.llvm.org/D35735https://bugs.llvm.org/show_bug.cgi?id=33881
llvm-svn: 309007
definition, added warnings, PS4 defaults, and Driver changes needed for
our compiler.
A patch by Filipe Cabecinhas, Pierre Gousseau and Katya Romanova!
Differential Revision: http://reviews.llvm.org/D11279
llvm-svn: 248546
Introduce ToolChain::getSupportedSanitizers() that would return the set
of sanitizers available on given toolchain. By default, these are
sanitizers which don't necessarily require runtime support and are
not toolchain- or architecture-dependent.
Sanitizers (ASan, DFSan, TSan, MSan etc.) which cannot function
without runtime library are marked as supported only on platforms
for which we actually build these runtimes.
This would allow more fine-grained checks in the future: for instance,
we have to restrict availability of -fsanitize=vptr to Mac OS 10.9+
(PR23539).
Update test cases accrodingly: add tests for certain unsupported
configurations, remove test cases for -fsanitize=vptr + PS4
integration, as we don't build the runtime for PS4 at the moment.
This change was first submitted as r239953 and reverted in r239958.
The problem was and still is in Darwin toolchains, which get the
knowledge about target platform too late after initializaition, while
now we require this information when ToolChain::getSanitizerArgs() is
called. r240170 works around this issue.
llvm-svn: 240179
Summary:
Introduce ToolChain::getSupportedSanitizers() that would return the set
of sanitizers available on given toolchain. By default, these are
sanitizers which don't necessarily require runtime support (i.e.
set from -fsanitize=undefined-trap).
Sanitizers (ASan, DFSan, TSan, MSan etc.) which cannot function
without runtime library are marked as supported only on platforms
for which we actually build these runtimes.
This would allow more fine-grained checks in the future: for instance,
we have to restrict availability of -fsanitize=vptr to Mac OS 10.9+
(PR23539)
Update test cases accrodingly: add tests for certain unsupported
configurations, remove test cases for -fsanitize=vptr + PS4
integration, as we don't build the runtime for PS4 at the moment.
Test Plan: regression test suite
Reviewers: pcc
Subscribers: cfe-commits, filcab, eugenis, thakis, kubabrecka, emaste, rsmith
Differential Revision: http://reviews.llvm.org/D10467
llvm-svn: 239953
Summary:
We were claiming the -f*exceptions arguments when looking for the
RTTIMode. This makes us not warn about unused arguments if compiling a C
file with -fcxx-exceptions.
This patch fixes it by not claiming the exception-related arguments at
that point.
Reviewers: rsmith, samsonov
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D8507
llvm-svn: 232860
This patch removes the huge blob of code that is dealing with
rtti/exceptions/sanitizers and replaces it with:
A ToolChain function which, for a given set of Args, figures out if rtti
should be:
- enabled
- disabled implicitly
- disabled explicitly
A change in the way SanitizerArgs figures out what sanitizers to enable
(or if it should error out, or warn);
And a check for exceptions/rtti interaction inside addExceptionArgs.
The RTTIMode algorithm is:
- If -mkernel, -fapple-kext, or -fno-rtti are passed, rtti was disabled explicitly;
- If -frtti was passed or we're not targetting the PS4, rtti is enabled;
- If -fexceptions or -fcxx-exceptions was passed and we're targetting
the PS4, rtti was enabled implicitly;
- If we're targetting the PS4, rtti is disabled implicitly;
- Otherwise, rtti is enabled;
Since the only flag needed to pass to -cc1 is -fno-rtti if we want to
disable it, there's no problem in saying rtti is enabled if we're
compiling C code, so we don't look at the input file type.
addExceptionArgs now looks at the RTTIMode and warns that rtti is being
enabled implicitly if targetting the PS4 and exceptions are on. It also
errors out if, targetting the PS4, -fno-rtti was passed, and exceptions
were turned on.
SanitizerArgs now errors out if rtti was disabled explicitly and the vptr
sanitizer was enabled implicitly, but just turns off vptr if rtti is
disabled but -fsanitize=undefined was passed.
Also fixed tests, removed duplicate name from addExceptionArgs comment,
and added one or two surrounding lines when running clang-format.
This changes test/Driver/fsanitize.c to make it not expect a warning when
passed -fsanitize=undefined -fno-rtti, but expect vptr to not be on.
Removed all users and definition of SanitizerArgs::sanitizesVptr().
Reviewers: samsonov
Subscribers: llvm-commits, samsonov, rsmith
Differential Revision: http://reviews.llvm.org/D7525
llvm-svn: 229801
Summary:
The PS4 defaults to -fno-rtti, and has to have rtti enabled when enabling
exceptions.
This commit makes clang add the -fno-rtti by default on the PS4, unless
-frtti was passed in.
It also diagnoses misuses for the PS4:
- Exceptions need rtti. Warn and enable rtti if no rtti flag was passed,
error if -fno-rtti was passed.
I also added a more general warning for when -fno-rtti is the default
(currently it's only on the PS4) and the vptr sanitizer is on.
Fixed a few tests, due to different flag order when passing cc1 arguments.
Reviewers: chandlerc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D7250
llvm-svn: 227518
Vedant Kumar