Commit Graph

19 Commits

Author SHA1 Message Date
Evgeniy Stepanov a284e559d7 [dfsan] Simplify code after r197677.
llvm-svn: 197679
2013-12-19 14:37:03 +00:00
Evgeniy Stepanov a9164e9e2a Add an explicit insert point argument to SplitBlockAndInsertIfThen.
Currently SplitBlockAndInsertIfThen requires that branch condition is an
Instruction itself, which is very inconvenient, because it is sometimes an
Operator, or even a Constant.

llvm-svn: 197677
2013-12-19 13:29:56 +00:00
Peter Collingbourne 0be79e1ade Introduce two command-line flags for the instrumentation pass to control whether the labels of pointers should be ignored in load and store instructions
The new command line flags are -dfsan-ignore-pointer-label-on-store and -dfsan-ignore-pointer-label-on-load. Their default value matches the current labelling scheme.

Additionally, the function __dfsan_union_load is marked as readonly.

Patch by Lorenzo Martignoni!

Differential Revision: http://llvm-reviews.chandlerc.com/D2187

llvm-svn: 195382
2013-11-21 23:20:54 +00:00
Alexey Samsonov 9b7e2b555c 80 cols
llvm-svn: 189473
2013-08-28 11:25:12 +00:00
Peter Collingbourne 28a10aff48 DataFlowSanitizer: Implement trampolines for function pointers passed to custom functions.
Differential Revision: http://llvm-reviews.chandlerc.com/D1503

llvm-svn: 189408
2013-08-27 22:09:06 +00:00
Peter Collingbourne a96296f3ab DataFlowSanitizer: correctly combine labels in the case where they are equal.
llvm-svn: 189133
2013-08-23 18:45:06 +00:00
Alexey Samsonov 6dae24df16 80 cols
llvm-svn: 189091
2013-08-23 07:42:51 +00:00
Peter Collingbourne 34f0c313e2 DataFlowSanitizer: Replace non-instrumented aliases of instrumented functions, and vice versa, with wrappers.
Differential Revision: http://llvm-reviews.chandlerc.com/D1442

llvm-svn: 189054
2013-08-22 20:08:15 +00:00
Peter Collingbourne 761a4fc475 DataFlowSanitizer: Factor the wrapper builder out to buildWrapperFunction.
Differential Revision: http://llvm-reviews.chandlerc.com/D1441

llvm-svn: 189053
2013-08-22 20:08:11 +00:00
Peter Collingbourne 59b1262d01 DataFlowSanitizer: Prefix the name of each instrumented function with "dfs$".
DFSan changes the ABI of each function in the module.  This makes it possible
for a function with the native ABI to be called with the instrumented ABI,
or vice versa, thus possibly invoking undefined behavior.  A simple way
of statically detecting instances of this problem is to prepend the prefix
"dfs$" to the name of each instrumented-ABI function.

This will not catch every such problem; in particular function pointers passed
across the instrumented-native barrier cannot be used on the other side.
These problems could potentially be caught dynamically.

Differential Revision: http://llvm-reviews.chandlerc.com/D1373

llvm-svn: 189052
2013-08-22 20:08:08 +00:00
Peter Collingbourne 444c59e270 DataFlowSanitizer: Add a debugging feature to help us track nonzero labels.
Summary:
When the -dfsan-debug-nonzero-labels parameter is supplied, the code
is instrumented such that when a call parameter, return value or load
produces a nonzero label, the function __dfsan_nonzero_label is called.
The idea is that a debugger breakpoint can be set on this function
in a nominally label-free program to help identify any bugs in the
instrumentation pass causing labels to be introduced.

Reviewers: eugenis

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1405

llvm-svn: 188472
2013-08-15 18:51:12 +00:00
Peter Collingbourne 9d31d6f329 DataFlowSanitizer: Instrumentation for memset.
Differential Revision: http://llvm-reviews.chandlerc.com/D1395

llvm-svn: 188412
2013-08-14 20:51:38 +00:00
Peter Collingbourne 68162e7512 DataFlowSanitizer: greylist is now ABI list.
This replaces the old incomplete greylist functionality with an ABI
list, which can provide more detailed information about the ABI and
semantics of specific functions.  The pass treats every function in
the "uninstrumented" category in the ABI list file as conforming to
the "native" (i.e. unsanitized) ABI.  Unless the ABI list contains
additional categories for those functions, a call to one of those
functions will produce a warning message, as the labelling behaviour
of the function is unknown.  The other supported categories are
"functional", "discard" and "custom".

- "discard" -- This function does not write to (user-accessible) memory,
  and its return value is unlabelled.
- "functional" -- This function does not write to (user-accessible)
  memory, and the label of its return value is the union of the label of
  its arguments.
- "custom" -- Instead of calling the function, a custom wrapper __dfsw_F
  is called, where F is the name of the function.  This function may wrap
  the original function or provide its own implementation.

Differential Revision: http://llvm-reviews.chandlerc.com/D1345

llvm-svn: 188402
2013-08-14 18:54:12 +00:00
Dmitry Vyukov 96a7084620 dfsan: fix lint warnings
llvm-svn: 188293
2013-08-13 16:52:41 +00:00
Peter Collingbourne fb3a2b4f97 DataFlowSanitizer: fix a use-after-free. Spotted by libgmalloc.
llvm-svn: 188216
2013-08-12 22:38:39 +00:00
Alexey Samsonov e4b5fb8851 Add SpecialCaseList::createOrDie() factory and use it in sanitizer passes
llvm-svn: 188169
2013-08-12 11:46:09 +00:00
Peter Collingbourne ae66d57bcf DataFlowSanitizer: Remove unreachable BBs so IR continues to verify
under the args ABI.

Differential Revision: http://llvm-reviews.chandlerc.com/D1316

llvm-svn: 188113
2013-08-09 21:42:53 +00:00
Peter Collingbourne a5689e69af Fix ARM build.
llvm-svn: 187944
2013-08-08 00:15:27 +00:00
Peter Collingbourne e5d5b0c71e DataFlowSanitizer; LLVM changes.
DataFlowSanitizer is a generalised dynamic data flow analysis.

Unlike other Sanitizer tools, this tool is not designed to detect a
specific class of bugs on its own.  Instead, it provides a generic
dynamic data flow analysis framework to be used by clients to help
detect application-specific issues within their own code.

Differential Revision: http://llvm-reviews.chandlerc.com/D965

llvm-svn: 187923
2013-08-07 22:47:18 +00:00