Commit Graph

1823 Commits

Author SHA1 Message Date
Kristof Umann 72649423c0 [analyzer][NFC] Fix inconsistent references to checkers as "checks"
Traditionally, clang-tidy uses the term check, and the analyzer uses checker,
but in the very early years, this wasn't the case, and code originating from the
early 2010's still incorrectly refer to checkers as checks.

This patch attempts to hunt down most of these, aiming to refer to checkers as
checkers, but preserve references to callback functions (like checkPreCall) as
checks.

Differential Revision: https://reviews.llvm.org/D67140

llvm-svn: 371760
2019-09-12 19:09:24 +00:00
Artem Dergachev f0bb45fac3 [analyzer] NFC: Move PathDiagnostic classes to libAnalysis.
At this point the PathDiagnostic, PathDiagnosticLocation, PathDiagnosticPiece
structures no longer rely on anything specific to Static Analyzer, so we can
move them out of it for everybody to use.

PathDiagnosticConsumers are still to be handed off.

Differential Revision: https://reviews.llvm.org/D67419

llvm-svn: 371661
2019-09-11 20:54:27 +00:00
Artem Dergachev 6b85f8e99b [analyzer] NFC: Move getStmt() and createEndOfPath() out of PathDiagnostic.
These static functions deal with ExplodedNodes which is something we don't want
the PathDiagnostic interface to know anything about, as it's planned to be
moved out of libStaticAnalyzerCore.

Differential Revision: https://reviews.llvm.org/D67382

llvm-svn: 371659
2019-09-11 20:54:21 +00:00
Artem Dergachev 8535b8ecf2 [analyzer] NFC: Re-implement stack hints as a side map in BugReport.
That's one of the few random entities in the PathDiagnostic interface that
are specific to the Static Analyzer. By moving them out we could let
everybody use path diagnostics without linking against Static Analyzer.

Differential Revision: https://reviews.llvm.org/D67381

llvm-svn: 371658
2019-09-11 20:54:17 +00:00
Artem Dergachev 2f169e7cdd [analyzer] NFC: Introduce sub-classes for path-sensitive and basic reports.
Checkers are now required to specify whether they're creating a
path-sensitive report or a path-insensitive report by constructing an
object of the respective type.

This makes BugReporter more independent from the rest of the Static Analyzer
because all Analyzer-specific code is now in sub-classes.

Differential Revision: https://reviews.llvm.org/D66572

llvm-svn: 371450
2019-09-09 20:34:40 +00:00
Gabor Borsik 080ecafdd8 Move prop-sink branch to monorepo.
llvm-svn: 371342
2019-09-08 19:23:43 +00:00
Artem Dergachev 6cee434ed1 [analyzer] Add minimal support for fix-it hints.
Allow attaching fixit hints to Static Analyzer BugReports.

Fixits are attached either to the bug report itself or to its notes
(path-sensitive event notes or path-insensitive extra notes).

Add support for fixits in text output (including the default text output that
goes without notes, as long as the fixit "belongs" to the warning).

Add support for fixits in the plist output mode.

Implement a fixit for the path-insensitive DeadStores checker. Only dead
initialization warning is currently covered.

Implement a fixit for the path-sensitive VirtualCall checker when the virtual
method is not pure virtual (in this case the "fix" is to suppress the warning
by qualifying the call).

Both fixits are under an off-by-default flag for now, because they
require more careful testing.

Differential Revision: https://reviews.llvm.org/D65182

llvm-svn: 371257
2019-09-06 20:55:29 +00:00
Artem Dergachev 2b1b4cab96 [analyzer] pr43179: Make CallDescription defensive against C variadic functions.
Most functions that our checkers react upon are not C-style variadic functions,
and therefore they have as many actual arguments as they have formal parameters.

However, it's not impossible to define a variadic function with the same name.
This will crash any checker that relies on CallDescription to check the number
of arguments but silently assumes that the number of parameters is the same.

Change CallDescription to check both the number of arguments and the number of
parameters by default.

If we're intentionally trying to match variadic functions, allow specifying
arguments and parameters separately (possibly omitting any of them).
For now we only have one CallDescription which would make use of those,
namely __builtin_va_start itself.

Differential Revision: https://reviews.llvm.org/D67019

llvm-svn: 371256
2019-09-06 20:55:24 +00:00
Benjamin Kramer 0581a44e02 Unbreak the build after r370798
llvm-svn: 370807
2019-09-03 18:24:56 +00:00
Kristof Umann 1b439659a8 [analyzer] NonNullParamChecker and CStringChecker parameter number in checker message
There are some functions which can't be given a null pointer as parameter either
because it has a nonnull attribute or it is declared to have undefined behavior
(e.g. strcmp()). Sometimes it is hard to determine from the checker message
which parameter is null at the invocation, so now this information is included
in the message.

This commit fixes https://bugs.llvm.org/show_bug.cgi?id=39358

Reviewed By: NoQ, Szelethus, whisperity

Patch by Tibor Brunner!

Differential Revision: https://reviews.llvm.org/D66333

llvm-svn: 370798
2019-09-03 17:57:01 +00:00
Kristof Umann 3b18b050b8 [analyzer] Add a checker option to detect nested dead stores
Enables the users to specify an optional flag which would warn for more dead
stores.
Previously it ignored if the dead store happened e.g. in an if condition.

if ((X = generate())) { // dead store to X
}

This patch introduces the `WarnForDeadNestedAssignments` option to the checker,
which is `false` by default - so this change would not affect any previous
users.
I have updated the code, tests and the docs as well. If I missed something, tell
me.

I also ran the analysis on Clang which generated 14 more reports compared to the
unmodified version. All of them seemed reasonable for me.

Related previous patches:
rGf224820b45c6847b91071da8d7ade59f373b96f3

Reviewers: NoQ, krememek, Szelethus, baloghadamsoftware

Reviewed By: Szelethus

Patch by Balázs Benics!

Differential Revision: https://reviews.llvm.org/D66733

llvm-svn: 370767
2019-09-03 15:22:43 +00:00
Adam Balogh 12f5c7f0c3 [Analyzer] Iterator Checkers - Make range errors and invalidated access fatal
Range errors (dereferencing or incrementing the past-the-end iterator or
decrementing the iterator of the first element of the range) and access of
invalidated iterators lead to undefined behavior. There is no point to
continue the analysis after such an error on the same execution path, but
terminate it by a sink node (fatal error). This also improves the
performance and helps avoiding double reports (e.g. in case of nested
iterators).

Differential Revision: https://reviews.llvm.org/D62893

llvm-svn: 370314
2019-08-29 09:35:47 +00:00
Artem Dergachev 630f7daf80 [analyzer] Fix analyzer warnings on analyzer.
Write tests for the actual crash that was found. Write comments and refactor
code around 17 style bugs and suppress 3 false positives.

Differential Revision: https://reviews.llvm.org/D66847

llvm-svn: 370246
2019-08-28 18:44:38 +00:00
Kristof Umann 09ce8ec78a [analyzer] Avoid unnecessary enum range check on LValueToRValue casts
Summary: EnumCastOutOfRangeChecker should not perform enum range checks on LValueToRValue casts, since this type of cast does not actually change the underlying type.   Performing the unnecessary check actually triggered an assertion failure deeper in EnumCastOutOfRange for certain input (which is captured in the accompanying test code).

Reviewers: #clang, Szelethus, gamesh411, NoQ

Reviewed By: Szelethus, gamesh411, NoQ

Subscribers: NoQ, gamesh411, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, donat.nagy, dkrupp, Charusso, bjope, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66014

llvm-svn: 369760
2019-08-23 14:21:13 +00:00
Artem Dergachev 85f7294e5a [analyzer] CastValueChecker: Correctly model results of based-to-derived casts.
Our SVal hierarchy doesn't allow modeling pointer casts as no-op. The
pointer type is instead encoded into the pointer object. Defer to our
usual pointer casting facility, SValBuilder::evalBinOp().

Fixes a crash.

llvm-svn: 369729
2019-08-23 03:24:04 +00:00
Artem Dergachev 62a76d0ae3 [analyzer] CastValueChecker: Provide DynamicTypeMap with pointer types only.
The idea to drop this requirement is good, but for now every other user
of DynamicTypeInfo expects pointer types.

Fixes a crash.

llvm-svn: 369728
2019-08-23 03:24:01 +00:00
Artem Dergachev af992e6d01 [analyzer] CastValueChecker: Avoid modeling casts between objects.
Our method only works correctly when casting a pointer to a pointer
or a reference to a reference.

Fixes a crash.

llvm-svn: 369727
2019-08-23 03:23:58 +00:00
Haojian Wu fcedc6a61b Remove an unused function, suppress -Wunused-function warning.
llvm-svn: 369629
2019-08-22 08:49:41 +00:00
Csaba Dabis 4d71600c11 [analyzer] CastValueChecker: Model isa(), isa_and_nonnull()
Summary: -

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D66423

llvm-svn: 369615
2019-08-22 02:57:59 +00:00
Csaba Dabis 22dc44ff89 [analyzer] CastValueChecker: Try to fix the buildbots
llvm-svn: 369609
2019-08-22 01:41:06 +00:00
Csaba Dabis e4bf456fce [analyzer] CastValueChecker: Rewrite dead header hotfix
llvm-svn: 369607
2019-08-22 00:36:42 +00:00
Csaba Dabis 0202c3596c [analyzer] CastValueChecker: Store the dynamic types and casts
Summary:
This patch introduces `DynamicCastInfo` similar to `DynamicTypeInfo` which
is stored in `CastSets` which are storing the dynamic cast informations of
objects based on memory regions. It could be used to store and check the
casts and prevent infeasible paths.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D66325

llvm-svn: 369605
2019-08-22 00:20:36 +00:00
Artem Dergachev d3971fe97b [analyzer] Improve VirtualCallChecker and enable parts of it by default.
Calling a pure virtual method during construction or destruction
is undefined behavior. It's worth it to warn about it by default.
That part is now known as the cplusplus.PureVirtualCall checker.

Calling a normal virtual method during construction or destruction
may be fine, but does behave unexpectedly, as it skips virtual dispatch.
Do not warn about this by default, but let projects opt in into it
by enabling the optin.cplusplus.VirtualCall checker manually.

Give the two parts differentiated warning text:

  Before:

    Call to virtual function during construction or destruction:
    Call to pure virtual function during construction

    Call to virtual function during construction or destruction:
    Call to virtual function during destruction

  After:

    Pure virtual method call:
    Call to pure virtual method 'X::foo' during construction
        has undefined behavior

    Unexpected loss of virtual dispatch:
    Call to virtual method 'Y::bar' during construction
        bypasses virtual dispatch

Also fix checker names in consumers that support them (eg., clang-tidy)
because we now have different checker names for pure virtual calls and
regular virtual calls.

Also fix capitalization in the bug category.

Differential Revision: https://reviews.llvm.org/D64274

llvm-svn: 369449
2019-08-20 21:41:14 +00:00
Jonas Devlieghere 2b3d49b610 [Clang] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

Differential revision: https://reviews.llvm.org/D66259

llvm-svn: 368942
2019-08-14 23:04:18 +00:00
Alex Langford 21872bc9bf [analyzer] Don't delete TaintConfig copy constructor
Summary:
Explicitly deleting the copy constructor makes compiling the function
`ento::registerGenericTaintChecker` difficult with some compilers. When we
construct an `llvm::Optional<TaintConfig>`, the optional is constructed with a
const TaintConfig reference which it then uses to invoke the deleted TaintConfig
copy constructor.

I've observered this failing with clang 3.8 on Ubuntu 16.04.

Reviewers: compnerd, Szelethus, boga95, NoQ, alexshap

Subscribers: xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, donat.nagy, dkrupp, Charusso, llvm-commits, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66192

llvm-svn: 368779
2019-08-14 01:09:07 +00:00
Kristof Umann 3f7c66d551 [analyzer][NFC] Prepare visitors for different tracking kinds
When we're tracking a variable that is responsible for a null pointer
dereference or some other sinister programming error, we of course would like to
gather as much information why we think that the variable has that specific
value as possible. However, the newly introduced condition tracking shows that
tracking all values this thoroughly could easily cause an intolerable growth in
the bug report's length.

There are a variety of heuristics we discussed on the mailing list[1] to combat
this, all of them requiring to differentiate in between tracking a "regular
value" and a "condition".

This patch introduces the new `bugreporter::TrackingKind` enum, adds it to
several visitors as a non-optional argument, and moves some functions around to
make the code a little more coherent.

[1] http://lists.llvm.org/pipermail/cfe-dev/2019-June/062613.html

Differential Revision: https://reviews.llvm.org/D64270

llvm-svn: 368777
2019-08-14 00:48:57 +00:00
Kristof Umann e1117addd6 [analyzer][NFC] Make sure that the BugReport is not modified during the construction of non-visitor pieces
I feel this is kinda important, because in a followup patch I'm adding different
kinds of interestingness, and propagating the correct kind in BugReporter.cpp is
just one less thing to worry about.

Differential Revision: https://reviews.llvm.org/D65578

llvm-svn: 368755
2019-08-13 22:03:08 +00:00
Kristof Umann fc76d8551f [analyzer][NFC] Refactoring BugReporter.cpp P4.: If it can be const, make it const
When I'm new to a file/codebase, I personally find C++'s strong static type
system to be a great aid. BugReporter.cpp is still painful to read however:
function calls are made with mile long parameter lists, seemingly all of them
taken with a non-const reference/pointer. This patch fixes nothing but this:
make a few things const, and hammer it until it compiles.

Differential Revision: https://reviews.llvm.org/D65382

llvm-svn: 368735
2019-08-13 18:48:08 +00:00
Kristof Umann 6d716ef181 [analyzer][NFC] Refactoring BugReporter.cpp P3.: std::shared_pointer<PathDiagnosticPiece> -> PathDiagnosticPieceRef
find clang/ -type f -exec sed -i 's/std::shared_ptr<PathDiagnosticPiece>/PathDiagnosticPieceRef/g' {} \;
git diff -U3 --no-color HEAD^ | clang-format-diff-6.0 -p1 -i

Just as C++ is meant to be refactored, right?

Differential Revision: https://reviews.llvm.org/D65381

llvm-svn: 368717
2019-08-13 16:45:48 +00:00
Csaba Dabis cf229d5752 [analyzer] CastValueChecker: Model castAs(), getAs()
Summary: Thanks to Kristóf Umann for the great idea!

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D65889

llvm-svn: 368383
2019-08-09 02:24:42 +00:00
Adam Balogh 8557f17d88 [Analyzer] Iterator Checkers - Fix for Crash on Iterator Differences
Iterators differences were mistakenly handled as random decrements which
causes an assertion. This patch fixes this.

llvm-svn: 367802
2019-08-05 06:45:41 +00:00
Gabor Borsik 2c8098374b Buildbot fix for r367190
llvm-svn: 367193
2019-07-28 14:57:41 +00:00
Gabor Borsik 4bde15fe1e [analyzer] Add yaml parser to GenericTaintChecker
While we implemented taint propagation rules for several
builtin/standard functions, there's a natural desire for users to add
such rules to custom functions.

A series of patches will implement an option that allows users to
annotate their functions with taint propagation rules through a YAML
file. This one adds parsing of the configuration file, which may be
specified in the commands line with the analyzer config:
alpha.security.taint.TaintPropagation:Config. The configuration may
contain propagation rules, filter functions (remove taint) and sink
functions (give a warning if it gets a tainted value).

I also added a new header for future checkers to conveniently read YAML
files as checker options.

Differential Revision: https://reviews.llvm.org/D59555

llvm-svn: 367190
2019-07-28 13:38:04 +00:00
Csaba Dabis 68983321cc [analyzer] MallocChecker: Prevent Integer Set Library false positives
Summary:
Integer Set Library using retain-count based allocation which is not
modeled in MallocChecker.

Reviewed By: NoQ

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64680

llvm-svn: 366391
2019-07-18 00:03:55 +00:00
Rui Ueyama 49a3ad21d6 Fix parameter name comments using clang-tidy. NFC.
This patch applies clang-tidy's bugprone-argument-comment tool
to LLVM, clang and lld source trees. Here is how I created this
patch:

$ git clone https://github.com/llvm/llvm-project.git
$ cd llvm-project
$ mkdir build
$ cd build
$ cmake -GNinja -DCMAKE_BUILD_TYPE=Debug \
    -DLLVM_ENABLE_PROJECTS='clang;lld;clang-tools-extra' \
    -DCMAKE_EXPORT_COMPILE_COMMANDS=On -DLLVM_ENABLE_LLD=On \
    -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ../llvm
$ ninja
$ parallel clang-tidy -checks='-*,bugprone-argument-comment' \
    -config='{CheckOptions: [{key: StrictMode, value: 1}]}' -fix \
    ::: ../llvm/lib/**/*.{cpp,h} ../clang/lib/**/*.{cpp,h} ../lld/**/*.{cpp,h}

llvm-svn: 366177
2019-07-16 04:46:31 +00:00
Fangrui Song 90e95bb289 Delete dead stores
llvm-svn: 365901
2019-07-12 14:04:34 +00:00
Csaba Dabis e856c0465d [analyzer] CastValueChecker: Remove a dump()
Summary: Fix a nit.
llvm-svn: 365590
2019-07-10 00:50:01 +00:00
Csaba Dabis 693936ab8f [analyzer] CastValueChecker: Model casts
Summary:
It models the LLVM casts:
- `cast<>`
- `dyn_cast<>`
- `cast_or_null<>`
- `dyn_cast_or_null<>`

It has a very basic support without checking the `classof()` function.

(It reapplies the reverted 'llvm-svn: 365582' patch with proper test file.)

Reviewed By: NoQ

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64374

llvm-svn: 365585
2019-07-10 00:20:03 +00:00
Csaba Dabis 6a29680efb Revert "[analyzer] CastValueChecker: Model casts"
This reverts commit 27cf666443.

llvm-svn: 365584
2019-07-09 23:47:09 +00:00
Csaba Dabis 27cf666443 [analyzer] CastValueChecker: Model casts
Summary:
It models the LLVM casts:
- `cast<>`
- `dyn_cast<>`
- `cast_or_null<>`
- `dyn_cast_or_null<>`

It has a very basic support without checking the `classof()` function.

Reviewed By: NoQ

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64374

llvm-svn: 365582
2019-07-09 23:33:23 +00:00
Kristof Umann 5e17ee1e35 [analyzer][IDF] Add a control dependency calculator + a new debug checker
I intend to improve the analyzer's bug reports by tracking condition
expressions.

01 bool b = messyComputation();
02 int i = 0;
03 if (b) // control dependency of the bug site, let's explain why we assume val
04        // to be true
05   10 / i; // warn: division by zero

I'll detail this heuristic in the followup patch, strictly related to this one
however:

* Create the new ControlDependencyCalculator class that uses llvm::IDFCalculator
  to (lazily) calculate control dependencies for Clang's CFG.
* A new debug checker debug.DumpControlDependencies is added for lit tests
* Add unittests

Differential Revision: https://reviews.llvm.org/D62619

llvm-svn: 365197
2019-07-05 12:17:44 +00:00
Csaba Dabis 57835bcfbd [analyzer] ReturnValueChecker: Model the guaranteed boolean return value of function calls
Summary: It models the known LLVM methods paired with their class.

Reviewers: NoQ, xazax.hun, ravikandhadai, baloghadamsoftware, Szelethus

Reviewed By: NoQ

Subscribers: dschuff, aheejin, mgorny, szepet, rnkovacs, a.sidorin,
             mikhail.ramalho, donat.nagy, dkrupp, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63915

llvm-svn: 365103
2019-07-04 00:50:50 +00:00
Kristof Umann 71a9dc39e4 [analyzer][Dominator] Add post dominators to CFG + a new debug checker
Transform clang::DominatorTree to be able to also calculate post dominators.

* Tidy up the documentation
* Make it clang::DominatorTree template class (similarly to how
  llvm::DominatorTreeBase works), rename it to clang::CFGDominatorTreeImpl
* Clang's dominator tree is now called clang::CFGDomTree
* Clang's brand new post dominator tree is called clang::CFGPostDomTree
* Add a lot of asserts to the dump() function
* Create a new checker to test the functionality

Differential Revision: https://reviews.llvm.org/D62551

llvm-svn: 365028
2019-07-03 11:39:12 +00:00
Fangrui Song 7264a474b7 Change std::{lower,upper}_bound to llvm::{lower,upper}_bound or llvm::partition_point. NFC
llvm-svn: 365006
2019-07-03 08:13:17 +00:00
Nathan Huckleberry 121401425d [analyzer] Support kfree in MallocChecker
Summary:
kmalloc is freed with kfree in the linux kernel. kmalloc support was
added in r204832, but kfree was not. Adding kfree fixes incorrectly
detected memory leaks.

Reviewers: NoQ, nickdesaulniers, dcoughlin, Szelethus

Reviewed By: NoQ, Szelethus

Subscribers: xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, Charusso, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64030

llvm-svn: 364875
2019-07-01 23:29:10 +00:00
Artem Dergachev 512f4838c4 [analyzer] NonnullGlobalConstants: Don't be confused by a _Nonnull attribute.
The NonnullGlobalConstants checker models the rule "it doesn't make sense
to make a constant global pointer and initialize it to null"; it makes sure
that whatever it's initialized with is known to be non-null.

Ironically, annotating the type of the pointer as _Nonnull breaks the checker.

Fix handling of the _Nonnull annotation so that it was instead one more reason
to believe that the value is non-null.

Differential Revision: https://reviews.llvm.org/D63956

llvm-svn: 364869
2019-07-01 23:02:14 +00:00
Artem Dergachev 35fdec1b54 [analyzer] CStringChecker: Modernize to use CallDescriptions.
This patch uses the new CDF_MaybeBuiltin flag to handle C library functions.
It's mostly an NFC/refactoring pass, but it does fix a bug in handling memset()
when it expands to __builtin___memset_chk() because the latter has
one more argument and memset() handling code was trying to match
the exact number of arguments. Now the code is deduplicated and there's
less room for mistakes.

Differential Revision: https://reviews.llvm.org/D62557

llvm-svn: 364868
2019-07-01 23:02:10 +00:00
Artem Dergachev 5c287f751a [analyzer] DeadStores: Update the crude suppression for files generated by IIG.
They changed the comments that we were looking for.

llvm-svn: 363995
2019-06-20 22:29:40 +00:00
Artem Dergachev 44820630df [analyzer] NFC: Change evalCall() to provide a CallEvent.
This changes the checker callback signature to use the modern, easy to
use interface. Additionally, this unblocks future work on allowing
checkers to implement evalCall() for calls that don't correspond to any
call-expression or require additional information that's only available
as part of the CallEvent, such as C++ constructors and destructors.

Differential Revision: https://reviews.llvm.org/D62440

llvm-svn: 363893
2019-06-19 23:33:42 +00:00
Artem Dergachev 3707b05211 [analyzer] DeadStores: Add a crude suppression files generated by DriverKit IIG.
IIG is a replacement for MIG in DriverKit: IIG is autogenerating C++ code.
Suppress dead store warnings on such code, as the tool seems to be producing
them regularly, and the users of IIG are not in position to address these
warnings, as they don't control the autogenerated code. IIG-generated code
is identified by looking at the comments at the top of the file.

Differential Revision: https://reviews.llvm.org/D63118

llvm-svn: 363892
2019-06-19 23:33:39 +00:00