Summary: In ObjC, when a method is called on nil, there is no NPE, the method is actually not called and the return value is 0/false/nil. There is an exception in the case where the return type is non-POD. In that case it's UB and we want to report an error.
Reviewed By: jvillard
Differential Revision: D26815687
fbshipit-source-id: 8126414ab
Summary: We were missing a part of the trace if it was going through a nil summary as the invalidation was set in the nil summary. Instead of creating a fresh value for return in the nil summary {self=0}{return=0}, we return self {self=0}{return=self}. This way we keep all the information about invalidation in the trace.
Reviewed By: jvillard
Differential Revision: D26871098
fbshipit-source-id: 6eb175e68
Summary:
Providing model for the android function TextUtils.isEmpty(). For now,
this always returns false assuming that the given value is not null.
Reviewed By: jvillard
Differential Revision: D26779619
fbshipit-source-id: 3d8e26813
Summary: Adding support for the Java instanceof operator in Pulse.
Reviewed By: jvillard
Differential Revision: D26275046
fbshipit-source-id: 8ba608cca
Summary: Adding temporary model for Collections/Map isEmpty() as an attempt to reduce false positives before we provide a full model for Collections.
Reviewed By: ezgicicek
Differential Revision: D26724085
fbshipit-source-id: d3418c173
Summary: `STARVATION` is currently used as a catch-all for several blocking events. This diff splits out `IPC_ON_UI_THREAD`.
Reviewed By: skcho
Differential Revision: D26691868
fbshipit-source-id: 618423793
Summary:
This diff uses config-impact-issues.exp instead of issues.exp, like in
the cost checker.
Reviewed By: ezgicicek
Differential Revision: D26723761
fbshipit-source-id: 9c6779479
Summary:
The javax.crypto.Mac classes behaves like a container
and can lead to race conditions when used in a concurrent context.
This adds Mac operations as container writes/reads in RacerD's models.
Pull Request resolved: https://github.com/facebook/infer/pull/1395
Test Plan: CI
Reviewed By: skcho
Differential Revision: D26722737
Pulled By: ngorogiannis
fbshipit-source-id: 74f03e9a5
Summary: When a method is called in ObjC on nil, there is no NPE, the method is actually not called and the return value is 0/false/nil. (There is an exception in the case where the return type is non-POD. In that case it's UB. This will be addressed later). To implement this behaviour we add additional summary to ObjC instance methods {self = 0} {return = 0}. We also want to make sure that inferred summary will not be used in we call a method on nil, hence, we add a path condition {self > 0} to get a contradiction when needed.
Reviewed By: jvillard
Differential Revision: D26664187
fbshipit-source-id: cdac2a5bb
Summary:
Currently, we report on all functions that are not config checked. However, the aim of the analysis is to only report on these for specific functions. Moreover, this has performance implications in practice.
This diff instead reports on functions that occur on a json file that is passed by the command line option `config-data-file`.
Reviewed By: skcho
Differential Revision: D26666336
fbshipit-source-id: 290cd3ada
Summary:
See added tests. Passing a variable by reference to a function `foo` can
cause the variable to be added to the global state so any stores after
that might be live as long as there is another function call after the
store (since the global state shouldn't outlive the scope of the
function). Currently we don't check that the latter is true; to report
these we would need to extend the abstract domain to remember which
stores have been made without a subsequent call.
Also change Blacklisted -> Dangerous everywhere since the corresponding
option is called "liveness_dangerous_classes".
Reviewed By: skcho
Differential Revision: D26606151
fbshipit-source-id: e869e5df1
Summary:
Providing model for Java `instanceof` operator that
avoids to return true when given object is null. This is a temporary
solution that will reduce FPs while we do not provide the correct
semantics for `instanceof`.
Reviewed By: jvillard
Differential Revision: D26608043
fbshipit-source-id: 87c82b906
Summary: This diff finds a declared variable name or declared field names from trace, then constructs an error message including access paths.
Reviewed By: jvillard
Differential Revision: D26544275
fbshipit-source-id: 135c90a1b
Summary:
`add_edge_on_src` is to prepare a stack location for a local variable. Before this diff, it was
called several times for each fields.
Reviewed By: jvillard
Differential Revision: D26543715
fbshipit-source-id: 49ebf2b65
Summary:
This resolves a few instances of false negatives; typically:
```
if (x == y) {
// HERE
*x = 10;
*y = 44;
// THERE
}
```
We used to get
```
HERE: &x->v * &y ->v' * v == v'
THERE: &x->v * &y ->v' * v == v' * v |-> 10 * v' |-> 44
```
The state at THERE was thus inconsistent and detected as such (v` and
`v'` are allocated separately in the heap hence cannot be equal).
Now we normalize the state more eagerly and so we get:
```
HERE: &x->v * &y->v
THERE: &x->v * &y->v * v |-> 44
```
Reviewed By: skcho
Differential Revision: D26488377
fbshipit-source-id: 568e685f0
Summary:
Instead of recording some facts as "known" (i.e., observed assignments),
record them as "pruned". This should be done any time the fact is not an
assignment, for instance when path-splitting on "is the argument =0?" as
in the model of `free()`.
Reviewed By: ezgicicek
Differential Revision: D26450362
fbshipit-source-id: 4fc980f90
Summary:
These were present for `std::optional` but not `folly::Optional` for
some reason.
Reviewed By: da319
Differential Revision: D26450400
fbshipit-source-id: 45051e828
Summary: In Objective-C, `static const int var = ..` is not recognized as ICE (integral constant expression) unlike C++. To handle such loads better, this diff adds a check for `constant_global_array` as a workaround.
Reviewed By: skcho
Differential Revision: D26369461
fbshipit-source-id: e2dae11f1
Summary:
Races in Nullsafe classes can undermine NPE safety despite the class passing the type checks.
This diff adds to the report text of THREAD_SAFETY_VIOLATION and GUARDEDBY_VIOLATION the following trailer:
> Data races in `Nullsafe` classes may still cause NPEs.
This only happens if the race is directly on a non-primitively-typed member field of the class.
It also uses distinct bug types (adds the suffix _NULLSAFE to the bug types above) for easier accounting.
Reviewed By: ezgicicek
Differential Revision: D26403274
fbshipit-source-id: 3cd6ca082
Summary:
The `--pulse-model-return-nonnull` config option currently works for C++. Now we
will be using it also for Java. Changing type from string list to regexp to
make it more general.
Reviewed By: ezgicicek
Differential Revision: D26367888
fbshipit-source-id: 9a06b9b32
Summary:
Modeling Java instanceof operator in Pulse. This
implementation does not yet provide the proper semantics for instanceof.
For now, it will always return true. This is temporary and should reduce the false positive rate.
Reviewed By: da319
Differential Revision: D26317089
fbshipit-source-id: 494e3dec5
Summary: D25952894 (1bce54aaf3) changes translation of struct assignments. This diff adopts to this change for loads from global struct arrays.
Reviewed By: skcho
Differential Revision: D26398627
fbshipit-source-id: cc1fb47ab
Summary:
Before this diff:
```
// Summary of const global
// { global -> v }
n$0 =* global
// n$0 -> {global}
x *= n$0
// x -> {global}
```
However, this is incorrect because we expect `x` have `v` instead of the abstract location of `global`.
To fix the issue, this diff lookups the initializer summary when `global` is evaluated as RHS of load statement.
After this diff:
```
// Summary of const global
// { global -> v }
n$0 =* global
// n$0 -> v
x *= n$0
// x -> v
```
Reviewed By: ezgicicek
Differential Revision: D26369645
fbshipit-source-id: 98b1ed085
Summary:
`SettableFuture.set` invokes callbacks registered prior to the call, which may also try to acquire extra locks. If the called of `set` already holds a lock this creates lock dependencies which may lead to deadlocks.
Here we warn whenever `set` is called under a lock taken in a different source file. This avoids reporting when a class internally manages locks and calls `set`, reasoning that developers will be aware this is happening.
Reviewed By: jvillard
Differential Revision: D25562190
fbshipit-source-id: d1b5cb69c
Summary:
This diff resets the id generator before generating ObjC getter/setter, so parsed results are the
same without regard to the generation order. Note that the order may change when we change the type
of Procname.t since their hash values are used for the hash set of procnames.
Reviewed By: ngorogiannis
Differential Revision: D26277348
fbshipit-source-id: a66d77845
Summary:
We are getting lots of FPs due to modeling `Provider.get` as expensive. This is coming from Dependency Injection and Infer cannot statically determine the type of the provider and determine whether that provider is expensive (requires a global analysis and instrumentation).
Instead, we are downgrading this method to the default constant cost.
Reviewed By: skcho
Differential Revision: D26223978
fbshipit-source-id: 79f81c997
Summary:
Dear Infer team,
To contribute to Infer community, I would like to integrate infer#'s language agnostic layer into Infer.
Please help to review, discuss and consider to merge this feature.
Thanks,
Xiaoyu
Pull Request resolved: https://github.com/facebook/infer/pull/1361
Reviewed By: skcho
Differential Revision: D25928458
Pulled By: jvillard
fbshipit-source-id: 7726150b8
Summary: Added some basic examples for Objective-C we want to address next in pulse nullptr dereference analysis. In particular, we should not get a `nil` dereference error when we call a method on `nil`, except if the method returns a non-POD (Plain Old Data) type.
Reviewed By: ezgicicek
Differential Revision: D26053402
fbshipit-source-id: 66f4600c3
Summary:
**Existing heuristic**: If we have a call `foo(n)` that has no model and summary for `foo`, we underestimate its cost as constant[1].
However, if we have a model for `foo` (e.g.with modeled cost O(n)) but applying the model to arguments causes the cost to be Top (e.g if `n` has Top size), then we could have Top-poisoning where all the callers up the call chain will have Top costs [2].
To prevent these unintended Top-poisioning when adding models, this diff applies *the same heuristic* to modeled calls with Top cost and gives them constant cost. This way, when adding models, we wouldn't be introducing more Tops than if we were to have no models in the first place.
[1] This is problematic in itself and causes many FPs at diff time, but otherwise we would be getting Tops everywhere and would not be able to give any meaningful cost. E.g. for fblite, if we were to give unknown calls Top cost, #procedures with Top cost increases form 5% to 38% and #procedures with linear cost reduces by 99.75%.
[2] This was observed for `containsValue` for Instagram where %Tops increased by 88% :(
Reviewed By: skcho
Differential Revision: D26174644
fbshipit-source-id: 232354923
Summary:
In practice, it is not easy to mark all of NOT initialized elements of array, so let's ignore the
array value at the moment.
Reviewed By: jvillard
Differential Revision: D25372449
fbshipit-source-id: 02b2e217c
Summary:
Having different behaviours inter-procedurally and intra-procedurally
sounds like a bad design in retrospect. The model of free() should not
depend on whether we currently know the value is not null as that means
some specs are missing from the summary.
Reviewed By: skcho
Differential Revision: D26019712
fbshipit-source-id: 1ac4316a5
Summary:
When a single field struct is initialized with "type x{v}" form, the translated result is not straightforward. For example,
```
struct t {
int val_;
};
void foo(t x) {
t y{x};
}
```
calls the copy constructor with `x`. This is good.
```
void foo(int n) {
t y{n};
}
```
assigns the integer `n` to `y.val_`. This is good.
```
t get_v();
void foo() {
t y{get_v()};
}
```
assigns return value of `get_v` to `y.val_`, rather than calling the copy constructor. This is not
good, but doesn't matter for actual running; `&y.val_` is the same to `&y` and `t` value is the same
to `int` value.
Reviewed By: jvillard
Differential Revision: D26146578
fbshipit-source-id: 8a81bb1db
Summary:
The test compiled with warnings, not sure how to prevent this in the
future as `infer` will suppress all warnings anyway (I wanted to add
`-Werror` to the test Makefile but that was defeated by infer itself).
Reviewed By: ezgicicek
Differential Revision: D26019682
fbshipit-source-id: d7f8fc2d8
Summary:
providing models for the checkState and checkArgument
functions, both used in Java code.
Reviewed By: da319
Differential Revision: D26101726
fbshipit-source-id: 0cc73d252
Summary: This diff fixes incorrect order of statements on `*p = !b;`.
Reviewed By: jvillard
Differential Revision: D26125069
fbshipit-source-id: 9dcefbd34
Summary: Creating model for the checkNotNull function from the Preconditions class in Pulse (Java). Whenever `checkNotNull(x)` is called, Pulse will assume that `x!= null`.
Reviewed By: ezgicicek
Differential Revision: D26075176
fbshipit-source-id: 40dcd395b
Summary:
This diff fixes incorrect order of statements on assignments.
In the translation of `LHS=RHS;`, if `RHS` is a complicated expression that introduced new nodes, eg a conditional expression, some load statements for `LHS` came after its usage. To avoid the issue, this diff forces it to introduce new nodes for `LHS`.
Reviewed By: jvillard
Differential Revision: D26099782
fbshipit-source-id: 27417cd99
Summary: This diff adds an additional parameter of struct return type in ObjC's methods. The additional parameter had been supported only in C/C++ functions/methods for 5 years (D2865091 (ec80d40bdd)). If there is no specific reason not to do that, let's do it and fix the incorrect frontend translations.
Reviewed By: jvillard
Differential Revision: D26049748
fbshipit-source-id: 414b3011f