Commit Graph

25 Commits

Author SHA1 Message Date
Kristóf Umann 479ea2a8ed [analyzer] Check the checker name, rather than the ProgramPointTag when silencing a checker
The program point created by the checker, even if it is an error node,
might not be the same as the name under which the report is emitted.
Make sure we're checking the name of the checker, because thats what
we're silencing after all.

Differential Revision: https://reviews.llvm.org/D102683
2021-05-19 12:40:09 +02:00
Kirstóf Umann 1614e35408 [analyzer][MallocChecker] PR46253: Correctly recognize standard realloc
https://bugs.llvm.org/show_bug.cgi?id=46253

This is an obvious hack because realloc isn't any more affected than other
functions modeled by MallocChecker (or any user of CallDescription really),
but the nice solution will take some time to implement.

Differential Revision: https://reviews.llvm.org/D81745
2020-06-16 17:50:06 +02:00
Balázs Kéri dcc04e09cf [Analyzer][MallocChecker] No warning for kfree of ZERO_SIZE_PTR.
Summary:
The kernel kmalloc function may return a constant value ZERO_SIZE_PTR
if a zero-sized block is allocated. This special value is allowed to
be passed to kfree and should produce no warning.

This is a simple version but should be no problem. The macro is always
detected independent of if this is a kernel source code or any other
code.

Reviewers: Szelethus, martong

Reviewed By: Szelethus, martong

Subscribers: rnkovacs, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, gamesh411, Charusso, martong, ASDenysPetrov, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76830
2020-03-30 10:33:14 +02:00
Artem Dergachev 7d4694547a [analyzer] Escape pointers stored into top-level parameters with destructors.
Writing stuff into an argument variable is usually equivalent to writing stuff
to a local variable: it will have no effect outside of the function.
There's an important exception from this rule: if the argument variable has
a non-trivial destructor, the destructor would be invoked on
the parent stack frame, exposing contents of the otherwise dead
argument variable to the caller.

If such argument is the last place where a pointer is stored before the function
exits and the function is the one we've started our analysis from (i.e., we have
no caller context for it), we currently diagnose a leak. This is incorrect
because the destructor of the argument still has access to the pointer.
The destructor may deallocate the pointer or even pass it further.

Treat writes into such argument regions as "escapes" instead, suppressing
spurious memory leak reports but not messing with dead symbol removal.

Differential Revision: https://reviews.llvm.org/D60112

llvm-svn: 358321
2019-04-13 02:01:45 +00:00
Artem Dergachev d3c54313ab [analyzer] NFC: Run many existing C++ tests with a custom operator new().
In order to provide more test coverage for inlined operator new(), add more
run-lines to existing test cases, which would trigger our fake header
to provide a body for operator new(). Most of the code should still behave
reasonably. When behavior intentionally changes, #ifs are provided.

Differential Revision: https://reviews.llvm.org/D42221

llvm-svn: 323376
2018-01-24 21:24:10 +00:00
Dominic Chen 184c6242fa Reland 4: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296895
2017-03-03 18:02:02 +00:00
Dominic Chen 09d66f7528 Revert "Reland 3: [analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit ea36f1406e1f36bf456c3f3929839b024128e468.

llvm-svn: 296841
2017-03-02 23:30:53 +00:00
Dominic Chen feaf9ff5ee Reland 3: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296837
2017-03-02 23:05:45 +00:00
Dominic Chen 4a90bf8c3f Revert "Reland 2: [analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit f93343c099fff646a2314cc7f4925833708298b1.

llvm-svn: 296836
2017-03-02 22:58:06 +00:00
Dominic Chen 1cb0256a3c Reland 2: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296835
2017-03-02 22:45:24 +00:00
Dominic Chen 00355a51d0 Revert "Reland: [analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit 1b28d0b10e1c8feccb971abb6ef7a18bee589830.

llvm-svn: 296422
2017-02-28 01:50:23 +00:00
Dominic Chen 59cd893320 Reland: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296414
2017-02-28 00:02:36 +00:00
Dominic Chen 8589e10c30 Revert "[analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit 8e7780b9e59ddaad1800baf533058d2c064d4787.

llvm-svn: 296317
2017-02-27 03:29:25 +00:00
Dominic Chen 02064a3076 [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296312
2017-02-27 02:36:15 +00:00
Anna Zaks 44cdeb1da2 [analyzer] Teach the analyzer that pointers can escape into __cxa_demangle
This fixes a reported false positive in the malloc checker.

Differential Revision: https://reviews.llvm.org/D27599

llvm-svn: 289886
2016-12-15 22:55:18 +00:00
Artem Dergachev d69e01297f [analyzer] pr31226: Disable CastSizeChecker in C++ because it's not quite ready.
Avoids a crash and a related false positive.

Investigation by Daniel Krupp!

llvm-svn: 288914
2016-12-07 16:12:26 +00:00
Jordan Rose 89bbd1fb64 [analyzer] Consolidate constant evaluation logic in SValBuilder.
Previously, this was scattered across Environment (literal expressions),
ExprEngine (default arguments), and RegionStore (global constants). The
former special-cased several kinds of simple constant expressions, while
the latter two deferred to the AST's constant evaluator.

Now, these are all unified as SValBuilder::getConstantVal(). To keep
Environment fast, the special cases for simple constant expressions have
been left in, but the main benefits are that (a) unusual constants like
ObjCStringLiterals now work as default arguments and global constant
initializers, and (b) we're not duplicating code between ExprEngine and
RegionStore.

This actually caught a bug in our test suite, which is awesome: we stop
tracking allocated memory if it's passed as an argument along with some
kind of callback, but not if the callback is 0. We were testing this in
a case where the callback parameter had a default value, but that value
was 0. After this change, the analyzer now (correctly) flags that as a
leak!

<rdar://problem/13773117>

llvm-svn: 180894
2013-05-01 23:10:44 +00:00
Anna Zaks 60bf5f45f7 [analyzer] Teach invalidateRegions that regions within LazyCompoundVal need to be invalidated
Refactor invalidateRegions to take SVals instead of Regions as input and teach RegionStore
about processing LazyCompoundVal as a top-level “escaping” value.

This addresses several false positives that get triggered by the NewDelete checker, but the
underlying issue is reproducible with other checkers as well (for example, MallocChecker).

llvm-svn: 178518
2013-04-02 01:28:24 +00:00
Anna Zaks 258f9357ef [analyzer]Revert part of r161511; suppresses leak false positives in C++
This is a "quick fix".

The underlining issue is that when a const pointer to a struct is passed
into a function, we do not invalidate the pointer fields. This results
in false positives that are common in C++ (since copy constructors are
prevalent). (Silences two llvm false positives.)

llvm-svn: 174468
2013-02-06 00:01:14 +00:00
Jordan Rose e37ab50a6e [analyzer] Report leaks at the closing brace of a function body.
This fixes a few cases where we'd emit path notes like this:

  +---+
 1|   v
  p = malloc(len);
  ^   |2
  +---+

In general this should make path notes more consistent and more correct,
especially in cases where the leak happens on the false branch of an if
that jumps directly to the end of the function. There are a couple places
where the leak is reported farther away from the cause; these are usually
cases where there are several levels of nested braces before the end of
the function. This still matches our current behavior for when there /is/
a statement after all the braces, though.

llvm-svn: 168070
2012-11-15 19:11:43 +00:00
Jordan Rose 6d671cc34a [analyzer] Always include destructors in the analysis CFG.
While destructors will continue to not be inlined (unless the analyzer
config option 'c++-inlining' is set to 'destructors'), leaving them out
of the CFG is an incomplete model of the behavior of an object, and
can cause false positive warnings (like PR13751, now working).

Destructors for temporaries are still not on by default, since
(a) we haven't actually checked this code to be sure it's fully correct
    (in particular, we probably need to be very careful with regard to
    lifetime-extension when a temporary is bound to a reference,
    C++11 [class.temporary]p5), and
(b) ExprEngine doesn't actually do anything when it sees a temporary
    destructor in the CFG -- not even invalidate the object region.

To enable temporary destructors, set the 'cfg-temporary-dtors' analyzer
config option to '1'. The old -cfg-add-implicit-dtors cc1 option, which
controlled all implicit destructors, has been removed.

llvm-svn: 163264
2012-09-05 22:55:23 +00:00
Ted Kremenek 722398f1d4 Fix analyzer tests.
llvm-svn: 162588
2012-08-24 20:39:55 +00:00
Anna Zaks 7577686a41 [analyzer] One more pointer escape test.
llvm-svn: 156214
2012-05-04 22:18:36 +00:00
Anna Zaks 228f9c7b68 [analyzer] Allow pointers escape through calls containing callback args.
(Since we don't have a generic pointer escape callback, modify
ExprEngineCallAndReturn as well as the malloc checker.)

llvm-svn: 156134
2012-05-03 23:50:28 +00:00
Anna Zaks 7e3e06a837 [analyzer] Add a malloc cpp test file.
Includes a test from a reported false positive fixed in some earlier
commit.

llvm-svn: 153702
2012-03-29 23:26:54 +00:00