Commit Graph

22 Commits

Author SHA1 Message Date
Evgeniy Stepanov 73583d5f2d [cfi] Safe handling of unaddressable vtable pointers (compiler-rt).
Avoid crashing when printing diagnostics for vtable-related CFI
errors. In diagnostic mode, the frontend does an additional check of
the vtable pointer against the set of all known vtable addresses and
lets the runtime handler know if it is safe to inspect the vtable.

http://reviews.llvm.org/D16824

llvm-svn: 259717
2016-02-03 22:19:04 +00:00
Evgeniy Stepanov 226965259d [cfi] Cross-DSO CFI diagnostic mode (compiler-rt part)
* add __cfi_slowpath_diag with a 3rd parameter which is a pointer to
  the diagnostic info for the ubsan handlers.
*__cfi_check gets a 3rd parameter as well.
* unify vcall/cast/etc and icall diagnostic info format, and merge
  the handlers to have a single entry point (actually two points due
  to abort/noabort variants).
* tests

Note that this comes with a tiny overhead in the non-diag mode:
cfi_slowpath must pass 0 as the 3rd argument to cfi_check.

llvm-svn: 258744
2016-01-25 23:34:38 +00:00
Alexey Samsonov 081a24e3a7 [UBSan] Implement runtime suppressions (PR25066).
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
2015-12-18 19:56:42 +00:00
Alexey Samsonov aff20ac3bd [UBSan] Clarify the way we disable de-duplication of reports from unrecoverable handlers.
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
2015-12-09 00:12:57 +00:00
Alexey Samsonov f3b9c895fa [UBSan] Add the ability to print more precise error kind in summary line.
Reviewers: rsmith, pcc

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D12215

llvm-svn: 245897
2015-08-24 23:18:49 +00:00
Peter Collingbourne 702548d9ea CFI: Get check-cfi passing on Windows.
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
2015-07-08 22:10:34 +00:00
Peter Collingbourne 175d633271 Add control flow integrity diagnosis function to UBSan runtime library.
Also includes execution tests for the feature.

Differential Revision: http://reviews.llvm.org/D10269

llvm-svn: 240111
2015-06-19 01:52:55 +00:00
Alexey Samsonov 0781e98cc7 [UBSan] Explicitly list all supported OS/arch pairs supported by UBSan.
llvm-svn: 233295
2015-03-26 17:26:04 +00:00
Alexey Samsonov d1c318657b [Sanitizer] Refactor SuppressionContext class.
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
2015-02-20 17:41:59 +00:00
Alexey Samsonov 760750c44f [UBSan] Optionally report summary in UBSan error reports.
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
2014-09-19 18:33:45 +00:00
Alexey Samsonov 2ccbc621df [UBSan] Add support for printing backtraces to all UBSan handlers
llvm-svn: 216289
2014-08-22 21:42:04 +00:00
Alexey Samsonov ff24fd2516 [UBSan] Allow to suppress reports from vptr checker for specified types.
Based on http://reviews.llvm.org/D4702 by Byoungyoung Lee!

llvm-svn: 214833
2014-08-05 01:24:22 +00:00
Alexey Samsonov 96591cd1f1 [UBSan] Introduce ScopedReport object.
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
2014-07-30 01:49:19 +00:00
Alexey Samsonov 20c5c7b723 [UBSan] Get pc/bp for stack unwinding as early as possible.
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
2014-07-29 23:22:41 +00:00
Alexey Samsonov bfa711c8b0 [UBSan] Add the ability to dump call stacks to -fsanitize=vptr
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
2014-07-23 18:44:54 +00:00
Richard Smith 6d9f13127c ubsan: Add checking for invalid downcasts. Per [expr.static.cast]p2 and p11,
base-to-derived casts have undefined behavior if the object is not actually an
instance of the derived type. Runtime library part.

llvm-svn: 175079
2013-02-13 21:18:23 +00:00
Will Dietz 765c266892 [ubsan] Add deduplication functionality, always enabled.
llvm-svn: 171948
2013-01-09 03:40:03 +00:00
Richard Smith 7e45562ad0 ubsan: Demangle class names, and be more informative when a reinterpret_cast
has got us to the wrong offset within an object.

llvm-svn: 170423
2012-12-18 09:30:21 +00:00
Richard Smith cf56ebd52a ubsan: When diagnosing something wrong somewhere in memory, emit a note
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
2012-12-18 06:30:32 +00:00
Will Dietz 2c36c71f5b [ubsan] Refactor handlers to have separate entry points for aborting.
If user specifies aborting after a recoverable failed check is
appropriate, frontend should emit call to the _abort variant.

Test this behavior with newly added -fsanitize-recover flag.

llvm-svn: 169113
2012-12-02 19:47:29 +00:00
Will Dietz b28179be10 [ubsan] Replace "fatal error" with "runtime error".
llvm-svn: 169112
2012-12-02 18:43:33 +00:00
Richard Smith 2f0d7d564c -fcatch-undefined-behavior checking for appropriate vptr value: library side.
llvm-svn: 166660
2012-10-25 02:07:02 +00:00