Commit Graph

12 Commits

Author SHA1 Message Date
Mitch Phillips 2e7be2a65a [cfi-verify] Validate there are no register clobbers between CFI-check and instruction execution.
Summary:
This patch adds another failure mode for `validateCFIProtection(..)`, wherein any register that affects the indirect control flow instruction is clobbered to between the CFI-check and the instruction's execution.

Also includes a modification to make MCInstrDesc::hasDefOfPhysReg public.

Reviewers: vlad.tsyrklevich

Reviewed By: vlad.tsyrklevich

Subscribers: llvm-commits, pcc, kcc

Differential Revision: https://reviews.llvm.org/D39820

llvm-svn: 318238
2017-11-15 00:35:26 +00:00
Mitch Phillips 02993892d8 [cfi-verify] Add DOT graph printing for GraphResult objects.
Allows users to view GraphResult objects in a DOT directed-graph format. This feature can be turned on through the --print-graphs flag.

Also enabled pretty-printing of instructions in output. Together these features make analysis of unprotected CF instructions much easier by providing a visual control flow graph.

Reviewers: pcc

Subscribers: llvm-commits, kcc, vlad.tsyrklevich

Differential Revision: https://reviews.llvm.org/D39819

llvm-svn: 318211
2017-11-14 22:43:13 +00:00
Mitch Phillips 3b9ea32ef8 [cfi-verify] Made FileAnalysis operate on a GraphResult rather than build one and validate it.
Refactors the behaviour of building graphs out of FileAnalysis, allowing for analysis of the GraphResult by the callee without having to rebuild the graph. Means when we want to analyse the constructed graph (planned for later revisions), we don't do repeated work.

Also makes CFI verification in FileAnalysis now return an enum that allows us to differentiate why something failed, not just that it did/didn't fail.

Reviewers: vlad.tsyrklevich

Subscribers: kcc, pcc, llvm-commits

Differential Revision: https://reviews.llvm.org/D39764

llvm-svn: 317927
2017-11-10 21:00:22 +00:00
Mitch Phillips c15bdf5598 [cfi-verify] Add blacklist parsing for result filtering.
Adds blacklist parsing behaviour for filtering results into four categories:

 - Expected Protected: Things that are not in the blacklist and are protected.
 - Unexpected Protected: Things that are in the blacklist and are protected.
 - Expected Unprotected: Things that are in the blacklist and are unprotected.
 - Unexpected Unprotected: Things that are not in the blacklist and are unprotected.

 now can optionally be invoked with a second command line argument, which specifies the blacklist file that the binary was built with.

Current  statistics for chromium:

Reviewers: vlad.tsyrklevich

Subscribers: mgorny, llvm-commits, pcc, kcc

Differential Revision: https://reviews.llvm.org/D39525

llvm-svn: 317364
2017-11-03 20:54:26 +00:00
Mitch Phillips 7db6f7a344 Parse DWARF information to reduce false positives.
Summary: Help differentiate code and data by parsing DWARF information. This will reduce false positive rates where data is placed in executable sections and is mistakenly parsed as code, resulting in an inflation in the number of indirect CF instructions (and hence an inflation of the number of unprotected).

Also prints the DWARF line data around the region of each indirect CF instruction.

Reviewers: pcc

Subscribers: probinson, llvm-commits, vlad.tsyrklevich, mgorny, aprantl, kcc

Differential Revision: https://reviews.llvm.org/D38654

llvm-svn: 317050
2017-10-31 23:20:05 +00:00
Mitch Phillips 5ff01cdc59 Add FileVerifier::isCFIProtected().
Add a CFI protection check that is implemented by building a graph and inspecting the output to deduce if the indirect CF instruction is CFI protected. Also added the output of this instruction to printIndirectInstructions().

Reviewers: vlad.tsyrklevich

Subscribers: llvm-commits, kcc, pcc, mgorny

Differential Revision: https://reviews.llvm.org/D38428

llvm-svn: 316610
2017-10-25 21:21:16 +00:00
Mitch Phillips d9af383d58 Made llvm-cfi-verify not execute unit tests on non-x86 builds.
Patched out from D38427.

Reviewers: vlad.tsyrklevich

Reviewed By: vlad.tsyrklevich

Subscribers: llvm-commits, kcc, pcc, mgorny

Differential Revision: https://reviews.llvm.org/D39197

llvm-svn: 316375
2017-10-23 20:54:01 +00:00
Mitch Phillips 99fa140501 Graph builder implementation.
Implement a localised graph builder for indirect control flow
instructions. Main interface is through GraphBuilder::buildFlowGraph,
which will build a flow graph around an indirect CF instruction. Various
modifications to FileVerifier are also made to const-expose some members
needed for machine code analysis done by the graph builder.

Reviewers: vlad.tsyrklevich

Reviewed By: vlad.tsyrklevich

Subscribers: llvm-commits, kcc, pcc

Differential Revision: https://reviews.llvm.org/D38427

llvm-svn: 316372
2017-10-23 20:25:19 +00:00
Mitch Phillips e140b3d122 Accidently merged an incomplete upstream patch in 10e6ee563a6b5ca498f27972ca6dbe6c308f1ac2 - reverting the changes.
llvm-svn: 316359
2017-10-23 18:17:56 +00:00
Mitch Phillips f91a31b7a3 Patch in
llvm-svn: 316358
2017-10-23 18:11:31 +00:00
Vlad Tsyrklevich 0ee2632403 MC Helpers for llvm-cfi-verify.
Add instruction analysis and machinecode traversal helpers in
preparation for control flow graph generation implementation.

Reviewers: vlad.tsyrklevich

Reviewed By: vlad.tsyrklevich

Subscribers: mgorny, llvm-commits, pcc, kcc

Differential Revision: https://reviews.llvm.org/D38424

llvm-svn: 315528
2017-10-11 23:17:29 +00:00
Vlad Tsyrklevich 89c3c8c403 Reland 'Classify llvm-cfi-verify.'
Summary: Move llvm-cfi-verify into a class in preparation for CFI analysis to come.

Reviewers: vlad.tsyrklevich

Reviewed By: vlad.tsyrklevich

Subscribers: mgorny, llvm-commits, pcc, kcc

Differential Revision: https://reviews.llvm.org/D38379

llvm-svn: 315504
2017-10-11 20:35:01 +00:00