Commit Graph

3613 Commits

Author SHA1 Message Date
Zurab Tsinadze a54d81f597 [analyzer] CERT: POS34-C
Summary:
This patch introduces a new checker:
`alpha.security.cert.pos.34c`

This checker is implemented based on the following rule:
https://wiki.sei.cmu.edu/confluence/x/6NYxBQ
The check warns if  `putenv` function is
called with automatic storage variable as an argument.

Differential Revision: https://reviews.llvm.org/D71433
2020-02-19 18:12:19 +01:00
Artem Dergachev 21efb06f0a Revert "[analyzer] Teach scan-build how to rebuild index.html without analyzing."
This reverts commit a807a068e6.

Buildbot failures :)
2020-02-18 09:48:29 +03:00
Artem Dergachev a807a068e6 [analyzer] Teach scan-build how to rebuild index.html without analyzing.
This is useful for performing custom build system integration that works by appending '--analyze --analyzer-output html' to all clang build commands.
For such users there is now still a way to have the fancy index.html file
in the output.

Differential Revision: https://reviews.llvm.org/D74467
2020-02-18 09:19:29 +03:00
Artem Dergachev 5a11233a2f [analyzer] VforkChecker: allow execve after vfork.
In the path-sensitive vfork() checker that keeps a list of operations
allowed after a successful vfork(), unforget to include execve() in the list.

Patch by Jan Včelák!

Differential Revision: https://reviews.llvm.org/D73629
2020-02-18 09:19:29 +03:00
Mark de Wever af20211944 [Sema] Fix pointer-to-int-cast for MSVC build bot
Revision 9658d895c8 breaks the clang-x64-windows-msvc build bot [1].
This should fix the unit test using the same method as used in 9658d895c8.

Note I don't have access to a Windows system so the patch is based on the
errors generated by the bot.

[1] http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/14358

Differential Revision: https://reviews.llvm.org/D74694
2020-02-16 19:09:59 +01:00
Mark de Wever 9658d895c8 [Sema] Adds the pointer-to-int-cast diagnostic
Converting a pointer to an integer whose result cannot represented in the
integer type is undefined behavior is C and prohibited in C++. C++ already
has a diagnostic when casting. This adds a diagnostic for C.

Since this diagnostic uses the range of the conversion it also modifies
int-to-pointer-cast diagnostic to use a range.

Fixes PR8718: No warning on casting between pointer and non-pointer-sized int

Differential Revision: https://reviews.llvm.org/D72231
2020-02-16 15:38:25 +01:00
Gabor Marton 536456a7e9 [analyzer] StdLibraryFunctionsChecker: Use platform dependent EOF and UCharMax
Summary:
Both EOF and the max value of unsigned char is platform dependent. In this
patch we try our best to deduce the value of EOF from the Preprocessor,
if we can't we fall back to -1.

Reviewers: Szelethus, NoQ

Subscribers: whisperity, xazax.hun, kristof.beyls, baloghadamsoftware, szepet, rnkovacs, a.sidorin, mikhail.ramalh

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74473
2020-02-13 13:51:51 +01:00
Richard Smith 7ae1b4a0ce Implement P1766R1: diagnose giving non-C-compatible classes a typedef name for linkage purposes.
Summary:
Due to a recent (but retroactive) C++ rule change, only sufficiently
C-compatible classes are permitted to be given a typedef name for
linkage purposes. Add an enabled-by-default warning for these cases, and
rephrase our existing error for the case where we encounter the typedef
name for linkage after we've already computed and used a wrong linkage
in terms of the new rule.

Reviewers: rjmccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74103
2020-02-07 11:47:37 -08:00
Gabor Horvath 643dee903c [analyzer] Move fuchsia.Lock checker to alpha
Differential Revision: https://reviews.llvm.org/D74004
2020-02-05 16:11:06 -08:00
Gabor Horvath e4f4a6c0f5 [analyzer] Prevent an assertion failure in PThreadLockChecker
When the implementations of the locking functions are available.

Differential Revision: https://reviews.llvm.org/D74003
2020-02-05 15:56:56 -08:00
Adam Balogh b198f16e1e [Analyzer] Model STL Algoirthms to improve the iterator checkers
STL Algorithms are usually implemented in a tricky for performance
reasons which is too complicated for the analyzer. Furthermore inlining
them is costly. Instead of inlining we should model their behavior
according to the specifications.

This patch is the first step towards STL Algorithm modeling. It models
all the `find()`-like functions in a simple way: the result is either
found or not. In the future it can be extended to only return success if
container modeling is also extended in a way the it keeps track of
trivial insertions and deletions.

Differential Revision: https://reviews.llvm.org/D70818
2020-02-05 17:59:08 +01:00
Artem Dergachev 482e236e56 [analyzer] Fix a couple of bugs in HTML report generation.
It should now produce valid HTML again.

Differential Revision: https://reviews.llvm.org/D73993
2020-02-05 17:16:38 +03:00
Artem Dergachev 4b05fc248b [analyzer] Suppress linker invocation in scan-build tests.
This should fix PS4 buildbots.
2020-02-04 00:12:24 +03:00
Artem Dergachev 5521236a18 [analyzer] Re-land 0aba69e "Add test directory for scan-build."
The tool is now looked for in the source directory rather than in the
install directory, which should exclude the problems with not being able
to find it.

The tests still aren't being run on Windows, but they hopefully will run
on other platforms that have shell, which hopefully also means Perl.

Differential Revision: https://reviews.llvm.org/D69781
2020-02-03 23:59:57 +03:00
Adam Balogh 9a08a3fab9 [Analyzer] Split container modeling from iterator modeling
Iterator modeling depends on container modeling,
but not vice versa. This enables the possibility
to arrange these two modeling checkers into
separate layers.

There are several advantages for doing this: the
first one is that this way we can keep the
respective modeling checkers moderately simple
and small. Furthermore, this enables creation of
checkers on container operations which only
depend on the container modeling. Thus iterator
modeling can be disabled together with the
iterator checkers if they are not needed.

Since many container operations also affect
iterators, container modeling also uses the
iterator library: it creates iterator positions
upon calling the `begin()` or `end()` method of
a containter (but propagation of the abstract
position is left to the iterator modeling),
shifts or invalidates iterators according to the
rules upon calling a container modifier and
rebinds the iterator to a new container upon
`std::move()`.

Iterator modeling propagates the abstract
iterator position, handles the relations between
iterator positions and models iterator
operations such as increments and decrements.

Differential Revision: https://reviews.llvm.org/D73547
2020-01-29 16:10:45 +01:00
Gabor Horvath f4c26d993b [analyzer] Add FuchsiaLockChecker and C11LockChecker
These are mostly trivial additions as both of them are reusing existing
PThreadLockChecker logic. I only needed to add the list of functions to
check and do some plumbing to make sure that we display the right
checker name in the diagnostic.

Differential Revision: https://reviews.llvm.org/D73376
2020-01-27 13:55:56 -08:00
Gabor Horvath c98d98ba9b [analyzer] Fix handle leak false positive when the handle dies too early
Differential Revision: https://reviews.llvm.org/D73151
2020-01-27 09:52:06 -08:00
Artem Dergachev dd22be1e3d [analyzer] PthreadLock: Implement mutex escaping.
Differential Revision: https://reviews.llvm.org/D37812
2020-01-24 18:43:24 +03:00
Artem Dergachev 15624a7bda [analyzer] PthreadLock: Add more XNU rwlock unlock functions.
Differential Revision: https://reviews.llvm.org/D37807
2020-01-24 18:43:23 +03:00
Artem Dergachev 80fd37f9d6 [analyzer] PthreadLock: Fix return value modeling for XNU lock functions.
Differential Revision: https://reviews.llvm.org/D37806
2020-01-24 18:43:23 +03:00
Gabor Horvath 5911268e44 [analyzer] Improve FuchsiaHandleChecker's diagnostic messages
Differential Revision: https://reviews.llvm.org/D73229
2020-01-23 09:16:40 -08:00
Gabor Marton bc29069dc4 [analyzer] Enable PlacementNewChecker by default 2020-01-21 13:23:10 +01:00
Joe Ranieri 5ee616a710 [analyzer] Fix SARIF column locations
Differential revision: https://reviews.llvm.org/D70689
2020-01-14 15:38:30 -05:00
Gabor Marton 13ec473b9d [analyzer] Move PlacementNewChecker to alpha 2020-01-10 19:35:25 +01:00
Gabor Marton 5e7beb0a41 [analyzer] Add PlacementNewChecker
Summary:
This checker verifies if default placement new is provided with pointers
to sufficient storage capacity.

Noncompliant Code Example:
  #include <new>
  void f() {
    short s;
    long *lp = ::new (&s) long;
  }

Based on SEI CERT rule MEM54-CPP
https://wiki.sei.cmu.edu/confluence/display/cplusplus/MEM54-CPP.+Provide+placement+new+with+properly+aligned+pointe
This patch does not implement checking of the alignment.

Reviewers: NoQ, xazax.hun

Subscribers: mgorny, whisperity, xazax.hun, baloghadamsoftware, szepet,
rnkovacs, a.sidorin, mikhail.ramalho, donat

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71612
2020-01-10 17:59:06 +01:00
serge-sans-paille cee4a1c957 Improve support of GNU mempcpy
- Lower to the memcpy intrinsic
- Raise warnings when size/bounds are known

Differential Revision: https://reviews.llvm.org/D71374
2020-01-09 17:31:00 +01:00
Gabor Horvath 59878ec809 [analyzer] Add path notes to FuchsiaHandleCheck.
Differential Revision: https://reviews.llvm.org/D70725
2019-12-20 12:40:41 -08:00
Gabor Horvath 82923c71ef [analyzer] Add Fuchsia Handle checker
The checker can diagnose handle use after releases, double releases, and
handle leaks.

Differential Revision: https://reviews.llvm.org/D70470
2019-12-20 12:33:16 -08:00
Artem Dergachev b284005072 [analyzer] Add a syntactic security check for ObjC NSCoder API.
Method '-[NSCoder decodeValueOfObjCType:at:]' is not only deprecated
but also a security hazard, hence a loud check.

Differential Revision: https://reviews.llvm.org/D71728
2019-12-19 14:54:29 -08:00
Artem Dergachev f0ced2ddb4 [analysis] Re-discard type sugar when casting values retrieved from the Store.
Canonicalization was accidentally omitted in 6d3f43ec.
2019-12-18 18:00:57 -08:00
Artem Dergachev bce1cce6bf [analyzer] Teach MismatchedDealloc about initWithBytesNoCopy with deallocator.
MallocChecker warns when memory is passed into -[NSData initWithBytesNoCopy]
but isn't allocated by malloc(), because it will be deallocated by free().
However, initWithBytesNoCopy has an overload that takes an arbitrary block
for deallocating the object. If such overload is used, it is no longer
necessary to make sure that the memory is allocated by malloc().
2019-12-18 14:19:17 -08:00
Artem Dergachev badba5118f [analyzer] NonnullGlobalConstants: Add support for kCFNull.
It's a singleton in CoreFoundation that always contains a non-null CFNullRef.
2019-12-18 12:08:15 -08:00
Gabor Horvath ea93d7d642 [CFG] Add an option to expand CXXDefaultInitExpr into aggregate initialization
This is useful for clients that are relying on linearized CFGs for evaluating
subexpressions and want the default initializer to be evaluated properly.

The upcoming lifetime analysis is using this but it might also be useful
for the static analyzer at some point.

Differential Revision: https://reviews.llvm.org/D71642
2019-12-17 17:56:06 -08:00
Artem Dergachev 6d3f43ec61 [analysis] Discard type qualifiers when casting values retrieved from the Store.
This canonicalizes the representation of unknown pointer symbols,
which reduces the overall confusion in pointer cast representation.

Patch by Vince Bridgers!

Differential Revision: https://reviews.llvm.org/D70836
2019-12-17 15:00:41 -08:00
Borsik Gabor 273e674252 [analyzer] Add support for namespaces to GenericTaintChecker
This patch introduces the namespaces for the configured functions and
also enables the use of the member functions.

I added an optional Scope field for every configured function. Functions
without Scope match for every function regardless of the namespace.
Functions with Scope will match if the full name of the function starts
with the Scope.
Multiple functions can exist with the same name.

Differential Revision: https://reviews.llvm.org/D70878
2019-12-15 12:11:22 +01:00
Artem Dergachev f450dd63a1 [analyzer] CStringChecker: Fix a crash on unknown value passed to strlcat.
Checkers should always account for unknown values.

Also use a slightly more high-level API that naturally avoids the problem.
2019-12-13 18:00:24 -08:00
Gabor Horvath 9fdcae7c81 [analyzer] Do not cache out on some shared implicit AST nodes
Some AST nodes which stands for implicit initialization is shared. The analyzer
will do the same evaluation on the same nodes resulting in the same state. The
analyzer will "cache out", i.e. it thinks that it visited an already existing
node in the exploded graph. This is not true in this case and we lose coverage.
Since these nodes do not really require any processing from the analyzer
we just omit them from the CFG.

Differential Revision: https://reviews.llvm.org/D71371
2019-12-11 17:15:12 -08:00
Gabor Horvath 5882e6f36f [analyzer] Escape symbols conjured into specific regions during a conservative EvalCall
This patch introduced additional PointerEscape callbacks after conservative
calls for output parameters. This should not really affect the current
checkers but the upcoming FuchsiaHandleChecker relies on this heavily.

Differential Revision: https://reviews.llvm.org/D71224
2019-12-11 11:44:10 -08:00
Artem Dergachev b01012b7c8 [analyzer] LocalizationChecker: Fix a crash on synthesized accessor stubs.
The checker was trying to analyze the body of every method in Objective-C
@implementation clause but the sythesized accessor stubs that were introduced
into it by 2073dd2d have no bodies.
2019-12-11 11:22:36 -08:00
Artem Dergachev 2b3f2071ec [analyzer] CStringChecker: Fix overly eager assumption that memcmp args overlap.
While analyzing code `memcmp(a, NULL, n);', where `a' has an unconstrained
symbolic value, the analyzer was emitting a warning about the *first* argument
being a null pointer, even though we'd rather have it warn about the *second*
argument.

This happens because CStringChecker first checks whether the two argument
buffers are in fact the same buffer, in order to take the fast path.
This boils down to assuming `a == NULL' to true. Then the subsequent check
for null pointer argument "discovers" that `a' is null.

Don't take the fast path unless we are *sure* that the buffers are the same.
Otherwise proceed as normal.

Differential Revision: https://reviews.llvm.org/D71322
2019-12-11 11:22:36 -08:00
Artem Dergachev 134faae042 [analyzer] CStringChecker: Improve warning messages.
Differential Revision: https://reviews.llvm.org/D71321
2019-12-11 11:22:36 -08:00
Adam Balogh 855d21a03a [Analyzer] Iterator Checkers: Replace `UnknownVal` in comparison result by a conjured value
Sometimes the return value of a comparison operator call is
`UnkownVal`. Since no assumptions can be made on `UnknownVal`,
this leeds to keeping impossible execution paths in the
exploded graph resulting in poor performance and false
positives. To overcome this we replace unknown results of
iterator comparisons by conjured symbols.

Differential Revision: https://reviews.llvm.org/D70244
2019-12-11 15:24:06 +01:00
Adam Balogh 6e9c58946e [Analyzer] Iterator Modeling: Print Container Data and Iterator Positions when printing the Program State
Debugging the Iterator Modeling checker or any of the iterator checkers
is difficult without being able to see the relations between the
iterator variables and their abstract positions, as well as the abstract
symbols denoting the begin and the end of the container.

This patch adds the checker-specific part of the Program State printing
to the Iterator Modeling checker.
2019-12-11 14:20:17 +01:00
Gabor Horvath 8434fbbee6 Revert "[analyzer] Keep track of escaped locals"
It was a step in the right direction but it is not clear how can this
fit into the checker API at this point. The pre-escape happens in the
analyzer core and the checker has no control over it. If the checker
is not interestd in a pre-escape it would need to do additional work
on each escape to check if the escaped symbol is originated from an
"uninteresting" pre-escaped memory region. In order to keep the
checker API simple we abandoned this solution for now.

We will reland this once we have a better answer for what to do on the
checker side.

This reverts commit f3a28202ef.
2019-12-10 16:42:03 -08:00
Gabor Horvath f3a28202ef [analyzer] Keep track of escaped locals
We want to escape all symbols that are stored into escaped regions.
The problem is, we did not know which local regions were escaped. Until now.
This should fix some false positives like the one in the tests.

Differential Revision: https://reviews.llvm.org/D71152
2019-12-10 08:51:33 -08:00
Artem Dergachev 040c39d50f [analyzer] Fix false positive on introspection of a block's internal layout.
When implementation of the block runtime is available, we should not
warn that block layout fields are uninitialized simply because they're
on the stack.
2019-12-06 13:24:20 -08:00
Balázs Kéri 7eafde981c [Checkers] Added support for freopen to StreamChecker.
Summary: Extend StreamChecker with a new evaluation function for API call 'freopen'.

Reviewers: NoQ, baloghadamsoftware, Szelethus, martong

Reviewed By: baloghadamsoftware, martong

Subscribers: martong, rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69948
2019-12-05 11:08:44 +01:00
Artem Dergachev 3c50f2544f [analyzer] Fix more ObjC accessor body farms after 2073dd2d.
Fix a crash when constructing a body farm for accessors of a property
that is declared and @synthesize'd in different (but related) interfaces
with the explicit ivar syntax.

This is a follow-up for 0b58b80e.
2019-12-04 16:29:08 -08:00
Borsik Gabor 89bc4c662c [analyzer] Add custom filter functions for GenericTaintChecker
This patch is the last of the series of patches which allow the user to
annotate their functions with taint propagation rules.

I implemented the use of the configured filtering functions. These
functions can remove taintedness from the symbols which are passed at
the specified arguments to the filters.

Differential Revision: https://reviews.llvm.org/D59516
2019-11-23 20:12:15 +01:00
Artem Dergachev a3b22da4e0 [CFG] Fix a flaky crash in CFGBlock::getLastCondition().
Using an end iterator of an empty CFG block was causing
a garbage pointer dereference.

Differential Revision: https://reviews.llvm.org/D69962
2019-11-21 21:55:58 -08:00