Summary:
This is to avoid a circular dependency issue in the future when creating
summaries might cause new reports: PulseReport depends on
PulseExecuationDomain so the latter cannot emit reports. Move summary
creation functions to PulseSummary instead, which sits above both of
these modules.
Also limit the responsabilities of PulseLatentIssues to just latent
issues in preparation for another change.
Reviewed By: skcho
Differential Revision: D26915799
fbshipit-source-id: 3275cd514
Summary: The translation of captured by reference variables has been fixed for ObjC blocks (D26945575 (778c629401)), so we do not need to ignore them in uninit analysis anymore.
Reviewed By: skcho
Differential Revision: D27063663
fbshipit-source-id: 447084d37
Summary:
This diff handles live variables in catch blocks. To do that, this diff adds another metadata,
`CatchEntry`.
Domain change: The domain is changed to
```
(normal:variables) x (exn:try_id->variables)
```
`exn` is a map from try-catch-id to a set of live variables that are live at the corresponding entry
of catch blocks.
Semantics change: It is a backward analysis.
* on `CatchEntry`: It updates `exn` with `try_id` and current `normal`.
* on `Call`: As of now, we assume all function calls can raise an exception. Therefore, it copies
all live variables in `exn` to `normal`.
* on `TryEntry`: It removes corresponding `try_id` from `exn`.
Reviewed By: jvillard
Differential Revision: D26952755
fbshipit-source-id: 1da854a89
Summary: This diff adds TryEntry and TryExit statements to the entry and exit of C++ `try` block, in order to handle exceptional control flow better in analyses.
Reviewed By: da319, jvillard
Differential Revision: D26946188
fbshipit-source-id: 33f4ae9e7
Summary: Adding option to suppress errors involving unknown code. If `--pulse-report-ignore-unknown-java-methods-patterns` is provided, reports containing skipped functions not matching at least one of the given regexps are suppressed.
Reviewed By: jvillard
Differential Revision: D26820575
fbshipit-source-id: b6e1df7b2
Summary:
Adapting error messages in Pulse so that they become more intuitive for
developers.
Reviewed By: jvillard
Differential Revision: D26887140
fbshipit-source-id: 896970ba2
Summary:
This changes the results. I think it's because we cut short paths to
ISL errors sooner now, before they are duplicated and moved. I could not
really assess what was going on though so could be wrong.
On OpenSSL 1.0.2d:
Before: 106 issues
After: 90 issues
Reviewed By: ezgicicek
Differential Revision: D26822331
fbshipit-source-id: e861e7fc2
Summary:
This will enable further improvements: basically we want to be able to
abort the symbolic execution of a single disjunct whenever an error is
detected. Right now there is only one kind of error, which is now
explicitly called `ReportableError`.
The next diff refactors Pulse.ISL to add its own error type so that we
are able to get rid of the isl_status field (ISLOk/ISLError) inside
abductive states. ISLError states are really `Error _` states but
previously it would have been too much of an API change to expose that.
Now it's all going to be part of `AccessResult.t`.
A further change will add another error type for when a value is found
to be 0 after the fact by the arithmetic.
Reviewed By: ezgicicek
Differential Revision: D26821178
fbshipit-source-id: 2923db8e7
Summary:
It makes more sense to return a list of results than a result of lists:
the latter stops the execution on *all* the disjuncts that would have
been in the list as soon as *one* of them fails. This is the same issue
we solved for non-ISL pulse models earlier.
Reviewed By: skcho
Differential Revision: D26818409
fbshipit-source-id: 7cc1d8b39
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:
Adapting existing model for `new` used in ObjC to Java.
This allows to compute dynamic type information and will facilitate
handling `instanceof`, for instance.
Changing attribute value type from Typ.Name.t to Typ.t to handle arrays.
Reviewed By: da319
Differential Revision: D26687839
fbshipit-source-id: 2cfcd0625
Summary:
Difficult to repro as most of the time other simplifactions catch this
before we actually get to dividing by zero. Nonetheless...
shamecube
Reviewed By: da319
Differential Revision: D26758187
fbshipit-source-id: b8718c515
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:
As a first step to support the Java `instanceof`
operator, this change allows the path condition to be appended with
`IsInstanceOf(var, typ)`.
Reviewed By: jvillard
Differential Revision: D26664009
fbshipit-source-id: cd19dce83
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:
There should be no equalities relevant to the precondition to
canonicalize against in the first place: equalities come either from
assignments (hence strictly to the post condition) or from PRUNE
statements, and we don't use the latter to canonicalize states anyway.
Reviewed By: skcho
Differential Revision: D26488378
fbshipit-source-id: 7923f71ea
Summary:
Pretty minor, it's more convenient to make it return the state and will
be used in a later diff when that function will actually sometimes
modify the state.
Reviewed By: skcho
Differential Revision: D26488376
fbshipit-source-id: a21eaf008
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:
Using more than the "known" part of the arithmetic could accidentally
leak "pruned" information into certain facts.
I noticed this when adding more term equality reasoning to pulse in
another diff. At the moment this has little effect but is still more
correct conceptually.
Reviewed By: ezgicicek
Differential Revision: D26450333
fbshipit-source-id: eb31da344
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:
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:
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:
Change most `t list access_result` to `t access_result list` so that the
Ok/Error is individual to each result in the list instead of having only
a toplevel Ok/Error affecting the whole list.
To make it not horrible to write this introduces new "monadic" operators
`let<*>` and `let<+>`. They are not entirely satisfactory but perhaps
it's just a notation issue as they are not quite bind/map operators
unlike what their notation might suggest. I'd say good enough for now.
The type change induced quite the churn but the new operators simplify
the code overall.
Reviewed By: skcho
Differential Revision: D26150505
fbshipit-source-id: 33764fae3
Summary:
Wrap the TOPL post-processing in the exit node debug wrapper too so that
we can see what it's doing if needed.
Reviewed By: skcho
Differential Revision: D26174365
fbshipit-source-id: dd63905ff
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:
States would be considered equal when they describe the same heap shape
even though their path conditions were different. Not good.
Reviewed By: skcho
Differential Revision: D26022135
fbshipit-source-id: 510913cde
Summary:
This is all dead code but I had to do this to try something else and I
don't want to have to do that again :)
Reviewed By: skcho
Differential Revision: D26022111
fbshipit-source-id: 622ca10b9
Summary:
It is better for the derived comparison functions to start by comparing
the single offset `Q.t` instead of the map. The order of the pair
doesn't matter so the easiest way to achieve that is by putting the
offset first.
Reviewed By: skcho
Differential Revision: D26022080
fbshipit-source-id: 874ea5c66
Summary:
It's a potentially expensive operation given that it does graph
isomorphism twice on equal values so add a fast path for when they are
the same pointer. Also comparing "skipped calls" doesn't need to care
about traces.
Reviewed By: da319
Differential Revision: D26022022
fbshipit-source-id: 8178df37b
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: Allowing Pulse NPE reports on Nullsafe classes to be suppressed. This is now possible via the optional argument --pulse-nullsafe-report-npe (default: true).
Reviewed By: da319
Differential Revision: D25997321
fbshipit-source-id: 98465df79
Summary:
When C and C++ code handle a common struct typed value, the struct
type is handled as a `CStruct` in the C code, but as a `CppClass` in
the C++ code. On the other hand, `Fieldname.t` contains a string of
field and **the struct type**. As a result, even if a same field is
accessed in C and C++ code, the accessed fieldnames are different.
```
void callee_in_c(struct s* x) {
x->a = 3;
}
void caller_in_cpp() {
struct s x;
x.a = 5;
callee_in_c(&x);
// HERE
}
```
For example, in the above code, `caller_in_cpp` sets the field `a` as
5, then calls `callee_in_c`, which sets the field `a` as 3. However,
at `HERE`, the value of `x` in Pulse is `{a -> 5, a -> 3}`, because the two
fieldnames are addressed as different ones.
To avoid the issue, this diff loosens the fieldname comparison in
Pulse.
Reviewed By: jvillard
Differential Revision: D26000812
fbshipit-source-id: 77142ebda
Jules Villard
Daiva Naudziuniene
Sungkeun Cho
Ezgi Çiçek
Gabriela Cunha Sampaio
Loc Le