Summary:
In the previous diffs, nullsafe behavior was changed to the following:
nested class mode is inherited from the outer class mode.
Though it is possible to e.g. make nested class Nullsafe and outer not,
or make nested class STRICT and outer just LOCAL, this is an edge case
and we don't want to recommend annotating nested classes by default. The
right way is to make outer class Nullsafe instead.
In this decision, we take into account user experience and codebase
readability.
Reviewed By: ngorogiannis
Differential Revision: D21255806
fbshipit-source-id: 0200cb555
Summary:
With this change, set of possibilities will be more actionable. Most
importantly, this will also educate users and make them realize how
Nullsafe trust works.
NOTE: yes, parenthesis are bit clumsy, but it was the easiest way to
make this change and let the phrase remain grammatically correct.
Reviewed By: artempyanykh
Differential Revision: D21231468
fbshipit-source-id: 4b5349fb5
Summary:
As artempyanykh pointed out, exposing trust list might encourage clients to
start writing business logic manipulating with trust lists outside of
NullsafeMode module, which we don't like to happen.
Reviewed By: artempyanykh
Differential Revision: D21230973
fbshipit-source-id: 39bd0b0d8
Summary:
In the previous diff we changed the semantics of nested classes w.r.t.
to Nullsafe.
Let's make it clear if users will attempt to misuse it.
Reviewed By: artempyanykh
Differential Revision: D21230717
fbshipit-source-id: 0ecc0dd06
Summary:
The order of model list is important to understand which model will be dispatched. Previously, the
models were shuffled with no pattern or rule. This diff sorts them and collects them as groups, so
making it easier to anticipate the dispatch.
Reviewed By: jvillard
Differential Revision: D21227541
fbshipit-source-id: 80be46d86
Summary: Similarly to Enum.name, we model Class.getCanonicalName as returning an arbitrary non-empty string.
Reviewed By: ngorogiannis
Differential Revision: D21207120
fbshipit-source-id: 1e2dbd1fd
Summary:
From the user perspective, the current behavior is confusing.
The users intutitively expect the inner class to inherit Nullsafe mode
from the outer one.
Having a class that is Nullsafe but the inner is not is hence dangerous
and misleading.
For the sake of completeness and to support gradual strictification, we
allow the nested class to improse additional strictness. Particularly,
the inner class can be Nullsafe but the outer can be not.
A follow up to this diff will include warnings telling about redundant and wrong usages of nested annotations.
Reviewed By: artempyanykh
Differential Revision: D21228055
fbshipit-source-id: 75755ad1d
Summary:
1. Most of trust list operations are abstract anyway, we don't actually
rely on the fact that this is list
2. Inside NullsafeMode.ml, we effectively need set operations, which is both more
idiomatic to express and Ocaml and faster
3. This will simplify implementation of the next diff which introduces
mode intersect operation
Reviewed By: artempyanykh
Differential Revision: D21207207
fbshipit-source-id: 0c1fc4426
Summary: Iterator invalidation traces were based on vector rather than iterator itself.
Reviewed By: ezgicicek
Differential Revision: D21202047
fbshipit-source-id: 62ce8a488
Summary: The transition function was using a complicated-looking and possibly-inefficient pattern of options for everything, when simple pattern matching with guards is sufficient.
Reviewed By: skcho
Differential Revision: D21179606
fbshipit-source-id: a37f97594
Summary:
Lets move the logic dealing with non-java classes outside of this module
so we can modify it easier in the next diff.
Reviewed By: artempyanykh
Differential Revision: D21204822
fbshipit-source-id: 67b5937bc
Summary:
Because of this bug, we evaluated anonymous class constructors in
Default mode, even if the underlying class was Nullsafe
Reviewed By: artempyanykh
Differential Revision: D21202986
fbshipit-source-id: a31318901
Summary: Specialise the above option to `true` and remove resulting dead code.
Reviewed By: dulmarod
Differential Revision: D21177041
fbshipit-source-id: 4a1c65850
Summary: This option makes RacerD angelic wrt the ownership of returned objects from procedures without summary. This will now be made the default and the option deprecated up the diff stack.
Reviewed By: dulmarod
Differential Revision: D21174676
fbshipit-source-id: 9c48d3d7d
Summary:
We model Enum.name as returing a constant name, rather than getting real field names. We did this
because we couldn't think of any big gains, in terms of analysis precision/performance, from getting
the real names.
Reviewed By: ezgicicek
Differential Revision: D21201730
fbshipit-source-id: a2dc01a44
Summary: This diff revises the models of Collection.set and get to handle its elements.
Reviewed By: ezgicicek
Differential Revision: D21201242
fbshipit-source-id: 9c248453d
Summary:
We ignored allocator models for vectors, and were not able to initialize vectors properly. This diff fixes this issue.
It also adds a test which was a FN before.
Reviewed By: skcho, jvillard
Differential Revision: D21089492
fbshipit-source-id: 6906cd1d1
Summary: D21155014 replaced `skip` call with a Load but this was not right. Instead, let's add a new builtin function (rather than skip) so that other analyses can freely model it as they want.
Reviewed By: jvillard
Differential Revision: D21178286
fbshipit-source-id: c214ccfb0
Summary: Java has this pattern of wrapping non-thread-safe containers in factory methods producing identically-typed results, but wrapped in a synchronised shell. This diff teaches RacerD about some common factory methods and uses the attribute domain to track the dynamic type of their results.
Reviewed By: ezgicicek
Differential Revision: D21155538
fbshipit-source-id: 42ebe6251
Summary: Complete the set of models for java containers that Infer should not report thread safety violations.
Reviewed By: ezgicicek
Differential Revision: D21138280
fbshipit-source-id: 01e1944b6
Summary: Models were partial and/or simply missing (`Map` writes!). Now the modelled containers use inheritance for conciseness (`List` reads are only those not caught by the `Collection` matcher, etc). Also, add URLs to documentation sources.
Reviewed By: ezgicicek
Differential Revision: D21132069
fbshipit-source-id: fefb360f0
Summary: `CFBridgingRelease` and `__bridge_transfer` which I'll model later, transfer the memory model from manual memory ref count to ARC (automatic ref count), so to avoid false positives this needs to be modelled. We can simply remove the Allocated attribute from the state, which means we won't try to track that memory anymore.
Reviewed By: skcho
Differential Revision: D21088218
fbshipit-source-id: 3520a0d59
Summary: This diff suppresses cost issues on lambda and auto-generated procedures, since they were too noisy.
Reviewed By: ezgicicek
Differential Revision: D21153619
fbshipit-source-id: 65ad6dcc3
Summary:
Replace horrible hack with ok hack.
The main difficulty in implementing the disjunctive domain is to avoid
the quadratic time complexity of executing the same disjuncts over and
over again when going around loops:
First time around a loop, assuming for example a single disjunct `d`:
```
[d]
loop body
[d1' \/ d2']
```
Second time around the same loop: the new pre will be the join of the
posts of predecessor nodes, so `old_pre \/ post(loop,old_pre)`, i.e.
`d \/ d1' \/ d2'`. Now we need to execute `loop body` again
*without running the symbolic execution of `d` again* (and the time after
that we'll want to not execute `d`, `d1'`, or `d2'`).
Horrible hack (before): Disjuncts have a boolean "visited" attached
that does its best to keep track of whether a given disjunct is old or
new. When executing a single *instruction* look at the flag and skip the
state if it's old. Of course we have no way to know for sure so it turns
out it was often wrongly re-executing old disjuncts. This was also
producing the wrong results over even simple loops: only the last
iteration would make it outside the loop for some reason. Overall, the
semantics were pretty untractable and shady at best.
New hack (this diff): only run instructions of a given *node* on
disjuncts that are not physically equal to the "pre" ones already in the
invariant map for the current node.
This gives the correct result over simple loops and a nice performance
improvement in general (probably the old heuristic was hitting the
quadratic bad case more often).
Reviewed By: skcho
Differential Revision: D21154063
fbshipit-source-id: 5ee38c68c
Summary:
This is a preparatory diff to make the actual change more readable. This
just moves the code around, trying to change it as little as possible.
Reviewed By: skcho
Differential Revision: D21154065
fbshipit-source-id: e086318c1
Summary:
This makes the API of [instrs] easier to work with at the price of some
duplication in the GADT.
This allows us to construct `[skip]` in `AbstractInterpreter` without
imposing a particular direction. This will make it the next diffs about
a disjunctive domain easier.
Reviewed By: skcho
Differential Revision: D21153694
fbshipit-source-id: f86c180fa
Summary:
We translated the expression `CXXStdInitializerListExpr` naively in D3058895 as a call to
a skip function, with the hope that it would be translated better in the future. However, the naive means that we lose access to the initialized list/array because we are simply skipping it. So, even if we want to model the initializer properly, we have to deal with the skip specially.
This diff tries to solve this problem by removing the skip call whenever
possible. Instead, we translate the underlying array/list as a Load, so
that when it is passed to the constructor, we can pick it up.
For the following initialization:
``` std::vector<int*> vec = {nullptr};
```
Before, we translated it as
```
*&0$?%__sil_tmpSIL_materialize_temp__n$7[0]:int* const =null
n$8=_fun___infer_skip_function(&0$?%__sil_tmpSIL_materialize_temp__n$7:int* const [1*8] const )
n$9=_fun_std::vector<int*,std::allocator<int*>>::vector(&vec:std::vector<int*,std::allocator<int*>>*,n$8:std::initializer_list<int*>)
```
However, this means, `n$8` would be result of something skipped which we can't reason about. Instead, we just pass the underlying initialized array now, so we get the following translation:
```
*&0$?%__sil_tmpSIL_materialize_temp__n$7[0]:int* const =null
n$8=*&0$?%__sil_tmpSIL_materialize_temp__n$7:int* const [1*8] const
n$9=_fun_std::vector<int*,std::allocator<int*>>::vector(&vec:std::vector<int*,std::allocator<int*>>*,n$8:std::initializer_list<int*>)
```
Reviewed By: jvillard
Differential Revision: D21155014
fbshipit-source-id: 75850b1e6
Summary:
It is true that `Info` issues are normally not intended for the end user
and in general should be hidden by default.
However, the current behavior - show them only if `--no-filtering` is
true - is super non-intuitive and complicates already complex reporting
logic.
Lets use the general "enable/disable" mechanism for controlling this.
Reviewed By: jvillard
Differential Revision: D21154140
fbshipit-source-id: 69e4c88e4
Summary:
Computing sledge's equality relation and normalising terms is costly. We
can avoid doing that most of the time by keeping the sledge path
condition lazily evaluated and only forcing it down to a value at two
critical points in the analysis:
1. Summary creation, to avoid storing unsatisfiable pre/posts that will have
to be needlessly executed by callers. This also saves us from having
to serialise the closures involved in the uncomputed form of lazy
values inside the pulse summaries.
2. Before reporting errors we check in the state is in fact satisfiable.
If not we just prune it away at that point.
This yields ~4x speedup on some targets.
Reviewed By: ezgicicek
Differential Revision: D21129759
fbshipit-source-id: a75fdd3bc
Summary:
This is mostly just a type change for now, more changes to come. This
doesn't make thing much faster yet because we force computations pretty
often to check for unsatisfiability (each function call and PRUNE node).
Next diff will build on that.
Reviewed By: skcho
Differential Revision: D21129758
fbshipit-source-id: 72200e2b1
Summary:
When encountering a constant, pulse creates an abstract value (a
variable) to represent it, and remembers that it's equal to it. The
problem is that pulse doesn't yet know how to deal with the fact that
some variables are going to be equal to each other.
This hacks around this issue in the case of constants, within the same
procedure, by remembering which constants have been assigned to which
place-holder variables, and serving those variables again when the same
constant is translated again.
Limitation: this doesn't work across procedure calls as the "constant
maps" are not saved in summaries.
Something to look out for: we don't want to make `if (p == NULL)` create
a path where `p` is invalid (we only make null invalid when we see an
assignment from 0, i.e. `p = NULL;`).
Reviewed By: ezgicicek
Differential Revision: D21089961
fbshipit-source-id: 5ebb85d0a
Summary:
1. Package will make the error too verbose.
2. We don't even need to say it is "class" because we say it in the error
description ("Class has 0 issues and can be marked Nullsafe").
Reviewed By: artempyanykh
Differential Revision: D21131998
fbshipit-source-id: 6ccca7615
Summary:
One source of false positives on container races is when the container member field is initialised to a concurrent version in a constructor, but the static type of the field doesn't reflect the thread safety of it.
This solution
- tracks flows from constructors of safe data structures to abstract addresses;
- initialises the initial attribute state when analysing a non-constructor method to that achieved by all constructors/class-initializers.
- checks for that attribute when recording container accesses.
Reviewed By: jvillard
Differential Revision: D21089428
fbshipit-source-id: 02a88f6e8
Summary:
As artempyanykh pointed out, `nullable` works much better for required fields
than `optional` in terms of x-plat.
Reviewed By: artempyanykh
Differential Revision: D21129614
fbshipit-source-id: b03c91b78
Summary: Modeling vector iterator with two internal fields: an internal array and an internal pointer. The internal array field points to the internal array field of a vector; the internal pointer field represents the current element of the array. For now `operator++` creates a fresh element inside the array.
Reviewed By: ezgicicek
Differential Revision: D21043304
fbshipit-source-id: db3be49ce
Summary:
The java source file parser should refuse to run on non
.java file. Also, as we expect some autogenerated source files to
break Java official syntax, we catch parsing error silently and
cancel location recording for them.
Reviewed By: jvillard
Differential Revision: D21089587
fbshipit-source-id: 35f1a1e28
Summary:
Now that only races rooted at formals or globals are reported, there is no point using the ownership domain to exclude accesses to locals, so remove the code that initialises the ownership of those.
Also, remove an accidentally quadratic use of `Map.bindings |> List.find` in `FormalMap` and simplify the analysis driver.
Reviewed By: skcho
Differential Revision: D21066855
fbshipit-source-id: 126080778
Summary:
Add a path condition to each symbolic state, represented in sledge's arithmetic domain. This gives a precise account of arithmetic constraints. In particular, it is relation and thus is more robust in the face of inter-procedural analysis.
This is gated behind a flag for now as there are performance issues with the new arithmetic.
Reviewed By: jberdine
Differential Revision: D20393947
fbshipit-source-id: b780de22a
Mitya Lyubarskiy
Sungkeun Cho
Daiva Naudziuniene
Nikos Gorogiannis
Ezgi Çiçek
Josh Berdine
Dulma Churchill
Jules Villard
David Pichardie
Scott Owens