71 Commits

Author SHA1 Message Date
Jordy Rose
330de22fe0 [analyzer] Remove now-unused constant. No functionality change.
llvm-svn: 152080
2012-03-06 00:33:35 +00:00
Jordy Rose
0accc6ae7b [analyzer] Fix unnecessary dyn_cast_or_null. No functionality change.
llvm-svn: 152078
2012-03-06 00:28:20 +00:00
Anna Zaks
12a8b90a36 [analyzer] Malloc should assume that ownership is transfered when
calling an ObjC method ending with 'NoCopy'.

llvm-svn: 152037
2012-03-05 17:42:10 +00:00
Anna Zaks
8dc53af5dc [analyzer] Fix a regression introduced in malloc with
attributes, introduced in r151188.

+ the test to catch it.

Thanks to Ahmed Charles for pointing this out.

llvm-svn: 151840
2012-03-01 22:06:06 +00:00
Anna Zaks
e0c03cab58 [analyzer] Malloc: A pointer might escape through CFContainers APIs,
funopen, setvbuf.

Teach the checker and the engine about these APIs to resolve malloc
false positives. As I am adding more of these APIs, it is clear that all
this should be factored out into a separate callback (for example,
region escapes). Malloc, KeyChainAPI and RetainRelease checkers could
all use it.

llvm-svn: 151737
2012-02-29 18:42:47 +00:00
Anna Zaks
06a77fc1b9 [analyzer] Fix Malloc False Positive (PR 12100)
When allocated buffer is passed to CF/NS..NoCopy functions, the
ownership is transfered unless the deallocator argument is set to
'kCFAllocatorNull'.

llvm-svn: 151608
2012-02-28 01:54:22 +00:00
Anna Zaks
43ffba2676 [analyzer] Leaks should be uniqued by the allocation point in the
closest function context. 

This prevents us from uniqueing all leaks from the same allocation
helper. radar://10932226

llvm-svn: 151592
2012-02-27 23:40:55 +00:00
Anna Zaks
7ac344a48a [analyzer] Malloc: reason about the ObjC messages and C++.
Assume none of the ObjC messages defined in system headers free memory,
except for the ones containing 'freeWhenDone' selector. Currently, just
assume that the region escapes to the messages with 'freeWhenDone'
(ideally, we want to treat it as 'free()').

For now, always assume that regions escape when passed to C++ methods.

llvm-svn: 151410
2012-02-24 23:56:53 +00:00
Anna Zaks
df901a4419 [analyzer] Malloc: unique leak reports by allocation site.
When we find two leak reports with the same allocation site, report only
one of them.

Provide a helper method to BugReporter to facilitate this.

llvm-svn: 151287
2012-02-23 21:38:21 +00:00
Anna Zaks
07de9c12f3 [analyzer] Invalidate the region passed to pthread_setspecific() call.
Make this call an exception in ExprEngine::invalidateArguments:
'int pthread_setspecific(ptheread_key k, const void *)' stores
a value into thread local storage. The value can later be retrieved
with 'void *ptheread_getspecific(pthread_key)'. So even thought the
parameter is 'const void *', the region escapes through the
call.

(Here we just blacklist the call in the ExprEngine's default
logic. Another option would be to add a checker which evaluates
the call and triggers the call to invalidate regions.)

Teach the Malloc Checker, which treats all system calls as safe about
the API.

llvm-svn: 151220
2012-02-23 01:05:27 +00:00
Anna Zaks
40a7eb3837 [analyzer] Malloc cleanup:
- We should not evaluate strdup in the Malloc Checker, it's the job of
CString checker, so just update the RefState to reflect allocated
memory.

- Refactor to reduce LOC: remove some wrapper auxiliary functions, make
all functions return the state and add the transition in one place
(instead of in each auxiliary function).

llvm-svn: 151188
2012-02-22 19:24:52 +00:00
Anna Zaks
199e8e585b [analyzer] Malloc checker: mark 'strdup' and 'strndup' as allocators.
llvm-svn: 151124
2012-02-22 03:14:20 +00:00
Anna Zaks
4ca45b1d00 [analyzer] Malloc: fix another false positive.
, when we return a symbol reachable to the malloced one via pointer
arithmetic.

llvm-svn: 151121
2012-02-22 02:36:01 +00:00
Anna Zaks
1526881ee0 [analyzer] Make Malloc aware of inter-procedural execution + basic
tests.

llvm-svn: 150993
2012-02-20 22:25:23 +00:00
Anna Zaks
e56167e8f8 [analyzer] Fix another false positive in the Malloc Checker, by making
it aware of CString APIs that return the input parameter.

Malloc Checker needs to know how the 'strcpy' function is
evaluated. Introduce the dependency on CStringChecker for that.
CStringChecker knows all about these APIs.

Addresses radar://10864450

llvm-svn: 150846
2012-02-17 22:35:31 +00:00
Anna Zaks
546c49c3b2 [analyzer] Malloc Checker: Clean up bug naming:
- Rename the category "Logic Error" -> "Memory Error".
 - Shorten all the messages.

llvm-svn: 150733
2012-02-16 22:26:12 +00:00
Anna Zaks
9eb7bc82ae [analyzer] Malloc Checker: Make the diagnostic visitor handle the case
of failing realloc. + Minor cleanups.

llvm-svn: 150732
2012-02-16 22:26:07 +00:00
Anna Zaks
d32ead82d9 [analyzer] Malloc Checker: Give up when a pointer escapes into a struct.
We are not properly handling the memory regions that escape into struct
fields, which led to a bunch of false positives. Be conservative here
and give up when a pointer escapes into a struct.

llvm-svn: 150658
2012-02-16 03:40:57 +00:00
Anna Zaks
d1ff1cbe23 [analyzer] Malloc checker: make a bit safer.
llvm-svn: 150556
2012-02-15 02:12:00 +00:00
Anna Zaks
ac06814d2f [analyzer] Malloc Checker: add support for reallocf, which always frees
the passed in pointer on failure.

llvm-svn: 150533
2012-02-15 00:11:25 +00:00
Anna Zaks
d51574850e [analyzer] Malloc Checker: add support for valloc + minor code
hardening.

llvm-svn: 150532
2012-02-15 00:11:22 +00:00
Anna Zaks
3d34834bb0 [analyzer] Make Malloc Checker optimistic in presence of inlining.
(In response of Ted's review of r150112.)

This moves the logic which checked if a symbol escapes through a
parameter to invalidateRegionCallback (instead of post CallExpr visit.)

To accommodate the change, added a CallOrObjCMessage parameter to
checkRegionChanges callback.

llvm-svn: 150513
2012-02-14 21:55:24 +00:00
Anna Zaks
ad01ef5fb9 [analyzer] Malloc Checker: realloc: add dependency between the symbols
in realloc map. 

If there is no dependency, the reallocated ptr will get garbage
collected before we know that realloc failed, which would lead us to
missing a memory leak warning.

Also added new test cases, which we can handle now.
Plus minor cleanups.

llvm-svn: 150446
2012-02-14 00:26:13 +00:00
Anna Zaks
8fd0f2a6cb [analyzer] Malloc Checker: realloc: correct the way we are handing the
case when size is 0.

llvm-svn: 150412
2012-02-13 20:57:07 +00:00
Anna Zaks
d56c8794d3 [analyzer] Malloc checker: rework realloc handling:
1) Support the case when realloc fails to reduce False Positives. (We
essentially need to restore the state of the pointer being reallocated.)

2) Realloc behaves differently under special conditions (from pointer is
null, size is 0). When detecting these cases, we should consider
under-constrained states (size might or might not be 0). The
old version handled this in a very hacky way. The code did not
differentiate between definite and possible (no consideration for
under-constrained states). Further, after processing each special case,
the realloc processing function did not return but chained to the next
special case processing. So you could end up in an execution in which
you first see the states in which size is 0 and realloc ~ free(),
followed by the states corresponding to size is not 0 followed by the
evaluation of the regular realloc behavior.

llvm-svn: 150402
2012-02-13 18:05:39 +00:00
Anna Zaks
41b84847bf [analyzer] Malloc Checker: reduce false negatives rate by assuming that
a pointer cannot escape through calls to system functions. Also, stop
after reporting the first use-after-free.

llvm-svn: 150315
2012-02-11 23:46:36 +00:00
Anna Zaks
3aa5225d5e [analyzer] Malloc Checker: Report a leak when we are returning freed
memory.
(As per one test case, the existing checker thought that this could
cause a lot of false positives - not sure if that's valid, to be
verified.)

llvm-svn: 150313
2012-02-11 21:44:39 +00:00
Anna Zaks
d3571e5ad3 [analyzer] Malloc checker: Leak bugs should be suppressed by sinks.
Resolves a common false positive, where we were reporting a leak inside
asserts

llvm-svn: 150312
2012-02-11 21:02:40 +00:00
Anna Zaks
bb1ef9011d [analyzer] MallocChecker: refactor/improve the symbol escape logic.
We use the same logic here as the RetainRelease checker.

llvm-svn: 150311
2012-02-11 21:02:35 +00:00
Anna Zaks
3188686c55 [analyzer] MallocChecker Cleanup - harden against crashes, fix an error
(use of return instead of continue), wording.

llvm-svn: 150215
2012-02-10 01:11:00 +00:00
Benjamin Kramer
541687f4be Remove unused fun.
llvm-svn: 150172
2012-02-09 12:05:18 +00:00
Anna Zaks
78edc2fb3c [analyzer] MallocChecker: address a diagnostic "fixme".
llvm-svn: 150158
2012-02-09 06:48:19 +00:00
Anna Zaks
2b5bb97986 [analyzer] Add custom path diagnostic to the Malloc Checker.
Very simple so far - we just highlight every allocation and release
site.

llvm-svn: 150156
2012-02-09 06:25:51 +00:00
Anna Zaks
12259b443d [analyzer] MallocChecker cleanup, more tests.
llvm-svn: 150155
2012-02-09 06:25:47 +00:00
Anna Zaks
a1b227b6a7 [analyzer] MallocChecker: implement pessimistic version of the checker,
which allows values to escape through unknown calls.

Assumes all calls but the malloc family are unknown.

Also, catch a use-after-free when a pointer is passed to a
function after a call to free (previously, you had to explicitly
dereference the pointer value).

llvm-svn: 150112
2012-02-08 23:16:56 +00:00
Anna Zaks
cd37bf4ec8 [analyzer] Split the MallocChecker into two versions - pessimistic and
optimistic.

TODO: actually implement the pessimistic version of the checker. Ex: it
needs to assume that any function that takes a pointer might free it.

The optimistic version relies on annotations to tell us which functions
can free the pointer.

llvm-svn: 150111
2012-02-08 23:16:52 +00:00
Anna Zaks
c68bf4c036 [analyzer] MallocChecker: convert from using evalCall to
post visit of CallExpr.

In general, we should avoid using evalCall as it leads to interference
with other checkers.

llvm-svn: 150086
2012-02-08 20:13:28 +00:00
Dylan Noblesmith
2c1dd2716a Basic: import SmallString<> into clang namespace
(I was going to fix the TODO about DenseMap too, but
that would break self-host right now. See PR11922.)

llvm-svn: 149799
2012-02-05 02:13:05 +00:00
Dylan Noblesmith
e27789991d Basic: import OwningPtr<> into clang namespace
llvm-svn: 149798
2012-02-05 02:12:40 +00:00
Benjamin Kramer
4903802fbf Move a method from IdentifierTable.h out of line and remove the SmallString include.
Fix all the transitive include users.

llvm-svn: 149783
2012-02-04 13:45:25 +00:00
Benjamin Kramer
3307c508c9 Move various diagnostic operator<< overloads out of line and remove includes of Diagnostic.h.
Fix all the files that depended on transitive includes of Diagnostic.h.
With this patch in place changing a diagnostic no longer requires a full rebuild of the StaticAnalyzer.

llvm-svn: 149781
2012-02-04 12:31:12 +00:00
Ted Kremenek
49b1e38e4b Change references to 'const ProgramState *' to typedef 'ProgramStateRef'.
At this point this is largely cosmetic, but it opens the door to replace
ProgramStateRef with a smart pointer that more eagerly acts in the role
of reclaiming unused ProgramState objects.

llvm-svn: 149081
2012-01-26 21:29:00 +00:00
David Blaikie
f47fa304a4 Remove unnecessary default cases in switches over enums.
This allows -Wswitch-enum to find switches that need updating when these enums are modified.

llvm-svn: 148281
2012-01-17 02:30:50 +00:00
Ted Kremenek
632e3b7ee2 [analyzer] Make the entries in 'Environment' context-sensitive by making entries map from
(Stmt*,LocationContext*) pairs to SVals instead of Stmt* to SVals.

This is needed to support basic IPA via inlining.  Without this, we cannot tell
if a Stmt* binding is part of the current analysis scope (StackFrameContext) or
part of a parent context.

This change introduces an uglification of the use of getSVal(), and thus takes
two steps forward and one step back.  There are also potential performance implications
of enlarging the Environment.  Both can be addressed going forward by refactoring the
APIs and optimizing the internal representation of Environment.  This patch
mainly introduces the functionality upon when we want to build upon (and clean up).

llvm-svn: 147688
2012-01-06 22:09:28 +00:00
Anna Zaks
8158ef0dec [analyzer] Be less pessimistic about invalidation of global variables
as a result of a call.

Problem:
Global variables, which come in from system libraries should not be
invalidated by all calls. Also, non-system globals should not be
invalidated by system calls.

Solution:
The following solution to invalidation of globals seems flexible enough
for taint (does not invalidate stdin) and should not lead to too
many false positives. We split globals into 3 classes:

* immutable - values are preserved by calls (unless the specific
global is passed in as a parameter):
     A :  Most system globals and const scalars

* invalidated by functions defined in system headers:
     B: errno

* invalidated by all other functions (note, these functions may in
turn contain system calls):
     B: errno
     C: all other globals (which are not in A nor B)

llvm-svn: 147569
2012-01-04 23:54:01 +00:00
Ted Kremenek
778d2bb8d4 Fix 80 col violations.
llvm-svn: 147566
2012-01-04 23:48:37 +00:00
Anna Zaks
c6aa531a8f [analyzer] Refactor checkers to use helper function for getting callee Decl and name.
We are getting name of the called function or it's declaration in a few checkers. Refactor them to use the helper function in the CheckerContext. 

llvm-svn: 145576
2011-12-01 05:57:37 +00:00
Anna Zaks
da4c8d6811 [analyzer] Rename generateNode -> addTransition in CheckerContext
Also document addTransition methods.

llvm-svn: 143059
2011-10-26 21:06:34 +00:00
Anna Zaks
b473816b4a [analyzer] Simplify CheckerContext
Remove dead members/parameters: ProgramState, respondsToCallback, autoTransition.
Remove addTransition method since it's the same as generateNode. Maybe we should
rename generateNode to genTransition (since a transition is always automatically
generated)?

llvm-svn: 142946
2011-10-25 19:57:06 +00:00
Anna Zaks
3eae33412d [analyze] Convert EndOfPath callback to use CheckerContext
Get rid of the EndOfPathBuilder completely.
Use the generic NodeBuilder to generate nodes.
Enqueue the end of path frontier explicitly.

llvm-svn: 142943
2011-10-25 19:56:48 +00:00