Summary:
Previously, we would lose track of ownership in code like
```
Obj owned = new Obj();
Obj stillOwned = id(owned); // would lose ownership here
stillOwned.f = ... // would report false alarm here
```
This diff partially addresses the problem by adding a notion of "unconditional" (always owned) or "conditional" (owned if some formal at index i is owned) ownership.
Now we can handle simple examples like the one above.
I say "partially" because we still can't handle cases where there are different reasons for conditional ownership, such as
```
oneOrTwo(Obj o1, Obj o2) { if (*) return o1; else return o2; } // we won't understand that this maintains ownership if both formals are owned
Obj stillOwned = oneOrTwo(owned1, owned2);
stillOwned.f = ... // we'll report a false alarm here
```
This can be addressed in the future, but will require slightly more work
Reviewed By: peterogithub
Differential Revision: D4520069
fbshipit-source-id: 99c7418
Summary: This fixes a wrong level of indirection when performing the type substitution.
Reviewed By: sblackshear
Differential Revision: D4521008
fbshipit-source-id: 7324ea6
Summary:
This fixes false positives we had in fields written by callees of a constructor (see new E2E test).
This is also a bit cleaner than what we did before; instead of special-casing constructors, we just use the existing ownership concept.
Reviewed By: peterogithub
Differential Revision: D4505161
fbshipit-source-id: a739ebc
Summary:
Constants are always "owned" in the sense that no one can mutate them.
In code like
```
Obj getX(boolean b) {
if (b) {
return null;
}
return new Obj();
}
```
, we need to understand this in order to infer that the returned value is owned.
This should fix a few FP's that I've seen.
Reviewed By: peterogithub
Differential Revision: D4485452
fbshipit-source-id: beae15b
Summary:
Infer used to report null dereference when field was accessed later:
```
vector<int> v;
int& a = v[0]; // should be EMPTY_VECTOR_ACCESS here, but it wasn't reported
int b = a; // was NULL_DEREFERENCE here
```
To avoid this problem, model all accesses to vector as dereference of its internal `beginPtr` field.
Reviewed By: jberdine
Differential Revision: D4481942
fbshipit-source-id: 2142894
Summary: This should fix the issue with broken invariants when the method specialization on pointer ends up doing a substitution on non pointer types
Reviewed By: sblackshear
Differential Revision: D4487232
fbshipit-source-id: f3fce84
Summary: The method `junit.framework.TestCase.setUp()` is always run before the other methods by the JUnit testing framework. So the method act as a class initializer.
Reviewed By: sblackshear
Differential Revision: D4487371
fbshipit-source-id: 1998801
Summary: Just adding some more test cases on how Infer handles dynamic dispatch.
Reviewed By: jberdine
Differential Revision: D4486529
fbshipit-source-id: d90ef42
Summary:
This modifies `CTrans_utils.dereference_value_from_result` function. Reasons:
1. Type in Sil.Load tuple is supposed to be the type of Ident.t field (result), not Exp.t (source)
2. Inside `dereference_value_from_result` we used wrong type when `~strip_pointer:true` - it used original type instead of the resulting one
3. Fixing (2), uncovered similar issue in `CTrans_utils.cast_operation` - it should have used resulting type, not original one
Changed tests are expected:
1. `deprecated_hack.cpp` test was how I discovered this issue (it was very wrong)
2. the other test also had issues, now it's correct
Sadly, there was no logic I followed when writing this change - I stuffed changes in a way that fits, but it may be breaking something somewhere else.
Reviewed By: jberdine
Differential Revision: D4481895
fbshipit-source-id: b139c59
Summary:
This diff adds a set of access paths holding a value returned from a method annotated with Functional to the domain.
If a "functional" value is written to a field, we won't count that right as an unprotected access.
The idea is to be able to use the Functional annotation to get rid of benign race false positive, such as:
```
Functional T iAlwaysReturnTheSameThing();
T mCache;
T memoizedGetter() {
if (mCache == null) {
mCache = iAlwaysReturnTheSameThing();
}
return mCache;
}
```
Although there is a write-write race on `mCache`, we don't care because it will be assigned to the same value regardless of which writer wins.
Reviewed By: peterogithub
Differential Revision: D4476492
fbshipit-source-id: cfa5dfc
Summary:
We warn on unsafe accesses to fields that occur in a public method (or are reachable from a public method).
We ought not to consider VisibleForTesting methods as public, since they are only public for testing purposes.
Reviewed By: peterogithub
Differential Revision: D4477648
fbshipit-source-id: 5f58914
Summary: Simple model for List methods that write to the collection.
Reviewed By: peterogithub
Differential Revision: D4453381
fbshipit-source-id: 19edc51
Summary:
Sometimes some instructions were never part of any CFG node and were not written to CFG at all. Add a mechanism that will create node and add them to CFG when they reach compoundStmt translation.
This is step forward to make `*x;` instruction actualy dereference x (it works in C already in C++ AST looks different though)
Reviewed By: dulmarod
Differential Revision: D4469139
fbshipit-source-id: b03b11c
Summary:
Previously, we would correctly be silent on code like `x = new T(); x.f = ...`, but would wrongly warn on code like `x = makeT(); x.f = ...`.
The reason is that we only allowed ownership through direct allocation.
This diff adds a boolean that specifies whether the return value is owned as part of the summary.
This allows us to correctly handle many common cases of (transitively) returning a freshly allocated object, but still won't work for understanding that ownership is maintained in examples like
`x = new T(); y = id(x); y.f = ...`.
Reviewed By: jvillard
Differential Revision: D4456864
fbshipit-source-id: b5eec02
Summary:
Eradicate currently considers a field initialized if it's simply accessed (not written to),
or initialized with another initialized field.
This fixes the issue.
Reviewed By: jvillard
Differential Revision: D4449541
fbshipit-source-id: 06265a8
Summary:
If we have code like
```
o.setF(source())
sink(o)
```
and `setF` is an unknown method, we probably want to report.
Reviewed By: jeremydubreil, mburman
Differential Revision: D4438896
fbshipit-source-id: 5edd204
Summary:
In code like
```
foo(o) {
iWriteToF(o)
}
```
, the condtional write to `f` in `iWriteToF` should become a conditional write for `foo`.
Reviewed By: peterogithub
Differential Revision: D4429160
fbshipit-source-id: f111ac4
Summary:
In code like
```
foo() {
Object local = new Object();
iWriteToAField(local);
}
```
, we don't want to warn because the object pointed to by `local` is owned by the caller, then ownership is transferred to the callee.
This diff supports this by introducing a notion of "conditional" and "unconditional" writes.
Conditional writes are writes that are rooted in a formal of the current procedure, and they are safe only if the actual bound to that formal is owned at the call site (as in the `foo` example above).
Unconditional writes are rooted in a local, and they are only safe if a lock is held in the caller.
Reviewed By: peterogithub
Differential Revision: D4429131
fbshipit-source-id: 2c6112b
Summary:
Races on volatile fields are less concerning than races on non-volatile fields because at least the read/write won't result in garbage.
For now, let's de-prioritize these writes by ignoring them.
Reviewed By: peterogithub
Differential Revision: D4434023
fbshipit-source-id: 05043ba
Summary:
Also make sure we don't introduce deprecated options in our repo, eg when
calling infer from infer.
Reviewed By: jeremydubreil
Differential Revision: D4430379
fbshipit-source-id: 77ea7fd
Summary: Just cleanup; gives us slightly less test code to maintain.
Reviewed By: jeremydubreil
Differential Revision: D4429265
fbshipit-source-id: d43c308
Summary:
Similar to marking classes ThreadConfined, we want to support marking fields as well.
The intended semantics are: don't warn on writes to the marked field outside of syncrhonization, but continue to warn on accesses to subfields.
Reviewed By: peterogithub
Differential Revision: D4406890
fbshipit-source-id: af8a114
Summary: Generalized the CppTrace into a Clang trace because we don't currently have separate checkers for Obj-C and Cpp. Happy to separate them later if there is a good reason
Reviewed By: akotulski
Differential Revision: D4394952
fbshipit-source-id: e288761
Summary:
Adding models that allow us to warn on unguarded accesses to subclasses of `Map`, but not on accesses of threadsafe containers like `ConcurrentMap`.
Lots more containers to model later, but stopping at `Map`s for now to make sure the approach looks ok.
Reviewed By: jvillard
Differential Revision: D4385306
fbshipit-source-id: d791eee