Summary:
The eventual goal is to stop having separate sections of the trace
("invalidation part" + "access part") when the "access part" already
goes through the invalidation step. For this, it needs to record when a
value is made invalid along the path.
This is also important for assignements to NULL/0/nullptr/nil: right now
the way we record that 0 is not a valid address is via an attribute
attached to the abstract value that corresponds to 0. This makes traces
inconsistent sometimes: 0 can appear in many places in the same function
and we won't necessarily pick the correct one. In other words, attaching
traces to *values* is fragile, as the same value can be produced in many
ways. On the other hand, histories are stored at the point of access, eg
x->f, so have a much better chance of being correct. See added test:
right now its traces is completely wrong and makes the 0 in `if
(utf16StringLen == 0)` the source of the NULL value instead of the
return of `malloc()`!
This diff makes the traces slightly more verbose for now but this is
fixed in a following diff as the traces that got longer are those that
don't actually need an "invalidation" trace.
Reviewed By: skcho
Differential Revision: D28098337
fbshipit-source-id: e17929259
Summary:
See added test: pulse sometimes insisted that an issue was latent even
though the condition that made it latent could not be influenced (hence
could the issue could never become manifest) by callers because it was
unrelated to the pre, i.e. it came from a mutation inside the function.
In these cases, we want to report the issue straight away instead of
keeping it latent.
Reviewed By: skcho
Differential Revision: D28002725
fbshipit-source-id: ce9e6f190
Summary:
Before returning a summary, restore formals to their initial values.
This gets rid of a false latent because the value in the path condition
is now garbage-collected.
Added a test for the tricky case of structs passed as values.
Reviewed By: skcho
Differential Revision: D28001229
fbshipit-source-id: 23dda5b43
Summary:
This diff avoids dereference of C struct, in its frontend and its semantics of Pulse. In SIL, C
struct is not first-class value, thus dereferencing on it does not make sense.
Reviewed By: ezgicicek
Differential Revision: D27953258
fbshipit-source-id: 348d56338
Summary: This diff copies each field values inside setter/getter of ObjC.
Reviewed By: ezgicicek
Differential Revision: D27940521
fbshipit-source-id: 9977cae75
Summary:
When a block value is passed via more than one-depth of function calls, it is not analyzed correctly
because current inlining mechanism (specializing objc block parameters) of the frontend works for
only one-depth of block passing. This diff gives up analyzing initialized-ness of captured
variables in ObjC to avoid FPs.
Reviewed By: da319
Differential Revision: D27885395
fbshipit-source-id: fc6b4663c
Summary:
Previously we were only taking constexpr into account on constructors.
Add this info to ProcAttributes.t instead by exporting it from the
plugin for all functions.
This allows SIOF to take constexpr into account in more cases as it's not
always good at capturing which functions *can* be constexpr-evaluated,
which caused false positives.
Delete now-useless is_constexpr in constructor types. This generated the
changes in frontend tests.
Some minor renamings of variants of is_const_expr -> is_constexpr.
Reviewed By: da319
Differential Revision: D27503433
fbshipit-source-id: 3d1972900
Summary: Added a new issue type for sending a message to nil when its return type is non-POD. To distinguish these issues from other nullptr dereference issues, we extend the `MustBeValid` attribute to contain the reason of why an address must be valid. For now a reason can only have `SelfOfNonPODReturnMethod` as it's value, but in the future we will use it for other nullability issue types, such as nil insertion into collections.
Reviewed By: jvillard
Differential Revision: D27762333
fbshipit-source-id: 689e5a431
Summary:
This diff evaluates a cpp vector given as a parameter symbolically. Especially, it addresses it as an array, so the cost checker can use its symbolic length correctly.
**About handling `cpp.vector_elem` field:**
The field is a virtual field of vector object that points to the array of vector elements. It was introduced in Inferbo to model semantics of vector operations.
Since many semantics of Inferbo depends on type information, it had collected type information of vector elements, whenever `cpp.vector_elem` field was introduced, as a *side-effect*. A problem is that it has *side-effect*, which means it may introduce non-deterministic analysis results depending on the type information of the virtual field.
This diff changes it not to collect the type information on `cpp.vector_elem` as a side-effect. Instead, it tries to write the information to the abstract states (abstract location) when possible.
Reviewed By: ezgicicek
Differential Revision: D27674935
fbshipit-source-id: f3d52cae7
Summary:
In D27430485 (a6ab4d38cf), we used the static cost of the callee to determine whether it was cheap/expensive. This diff improves on that by taking the whole instantiated cost of the function call (not just the callee's cost).
Also, if the callee is an unmodeled call, we consider it to be expensive as before.
Note: cost instantiation was used by hoisting. I refactored bunch of code there to reuse as much as code possible.
Reviewed By: skcho
Differential Revision: D27649302
fbshipit-source-id: 07d11f3dd
Summary: When instantiating the callee's cost, we have picked up the InferBo memory at the node corresponding to the last instruction. Instead, we should pick up right at the call instruction. Picking it up later might cause arguments to go out of scope.
Reviewed By: skcho
Differential Revision: D27652474
fbshipit-source-id: 5ab35cabb
Summary:
The output differs on Java 11 compared to Java 8: one prints an
interface, the other resolves to a class name.
Reviewed By: ezgicicek
Differential Revision: D27678552
fbshipit-source-id: c5a5d0c39
Summary:
Nullsafe/biabduction tests were sensitive to Java version: they were recorded for Java 8 but if the machine that is used to run the tests had Java 11, tests would fail. This diff aims to resolve this issue by
- making our tests produce java8-compatible bytecode so that tests don't fail on Java 11 machines
- removing nullsafe tests that exercise obscure Java 8 behavior that cannot be alleviated with backward compatible bytecode on Java 11
- changing lambda argument printing to be Java 11 compatible
Reviewed By: martintrojer
Differential Revision: D27500731
fbshipit-source-id: 77fe302ea
Summary:
This diff removes additional inferbo options `--bufferoverrun` from cost tests, since printing
inferbo issues is not that useful to understand cost results.
Reviewed By: ngorogiannis
Differential Revision: D27592496
fbshipit-source-id: 6ab3e6528
Summary:
Whenever an equality "t = v" (t an arbitrary term, v a variable) is
added (or "v = t"), remember the "t -> v" mapping after canonicalising t
and v. Use this to detect when two variables are equal to the same term:
`t = v` and `t = v'` now yields `v = v'` to be added to the equality
relation of variables. This increases the precision of the arithmetic
engine.
Interestingly, the impact on most code I've tried is:
1. mostly same perfs as before, if a bit slower (could be within noise)
2. slightly more (latent) bugs reported in absolute numbers
I would have expected it to be more expensive and yield fewer bugs (as
fewer false positives), but there could be second-order effects at play
here where we get more coverage. We definitely get more latent issues
due to dereferencing pointers after testing nullness, as can be seen in
the unit tests as well, which may alone explain (2).
There's some complexity when adding term equalities where the term
is linear, as we also need to add it to `linear_eqs` but `term_eqs` and
`linear_eqs` are interested in slightly different normal forms.
Reviewed By: skcho
Differential Revision: D27331336
fbshipit-source-id: 7314e127a
Summary:
When we don't know the value being shifted it may help to translate
bit-shifting into multiplication by a constant as it might surface
linear terms, eg `x<<1` is `2*x`.
Reviewed By: skcho
Differential Revision: D27464847
fbshipit-source-id: 9b3b5f0d0
Summary:
On some pathological examples of crypto primitives like libsodium, later
diffs make pulse grind to a halt due to an explosion in the size of
literals. This is at least partly due to the fact the arithmetic doesn't
operate modulo 2^64.
Due to the fact the arithmetic is confused in any case when we reach
such large numbers, cap them, currently at 2^128. This removes pathological
cases for now, even now on libsodium Pulse is ~5 times faster than before!
Take this opportunity to put the modified Q/Z modules in the own files.
Reviewed By: jberdine
Differential Revision: D27463933
fbshipit-source-id: 342d941e2
Summary:
This was added in C++14. Was investigating how SIOF dealt with this but
it turns out it already does the right thing as the translation unit of
global variable templates shows up as the place they are instantiated
(not the one where they are declared), which works well for SIOF
checking.
Reviewed By: da319
Differential Revision: D27500998
fbshipit-source-id: b8b9b9c48
Summary:
The title
Also notice that there is a duplication of an error.
Reviewed By: skcho
Differential Revision: D27426933
fbshipit-source-id: dbd2f861a
Summary: To support objc nil messaging for unknown function calls we prune `self` to be positive in the `normal` specification and add additional specification to handle nil case.
Reviewed By: skcho
Differential Revision: D27360757
fbshipit-source-id: 119999b30
Summary:
This addresses a test difference between java versions. Infer's java tests are recorded with Java8 where string concat with a constant string uses `toString`. However, if tests are run on a machine where Java 11 is used, string concat is done via `makeConcatWithConstants` which causes tests to fail.
As a workaround, we replace the test so that Java version dependent string concat is not used.
Reviewed By: ngorogiannis
Differential Revision: D27394621
fbshipit-source-id: dfe1af2ac
Summary:
Fixing `IsInstanceOf` term simplification for null case. Before, this
was only being done if value was known to be null at the moment of the
call to `instanceof`. Otherwise, the `IsInstanceOf` term would remain in
the formula unnecessarily.
Reviewed By: jvillard
Differential Revision: D27361025
fbshipit-source-id: 2d958a757
Summary:
Models for Java Map interface.
This consists of `Map.init()`, `Map.put(key, value)`, `Map.get(key)`,
`Map.containsKey(key)` and
`Map.isEmpty()`. With the exception of `Map.get(key)` and `Map.containsKey(key)`, these functions were modelled using the respective similar ones provided by the Java Collection interface.
Reviewed By: jvillard
Differential Revision: D27326716
fbshipit-source-id: e07f0c952
Summary:
The explicit marker for nondeterministic states was used to speed up the
shallow implementations of Topl, which ar enow removed.
Reviewed By: jvillard
Differential Revision: D27297019
fbshipit-source-id: 0fce93817
Summary:
Before this diff, TOPL had 3 implementations:
1. a post-processing of biabduction summaries
2. a post-processing of pulse summaries
3. a deep embedding in pulse
1 and 2 additionally require instrumenting SIL to generate monitors for
the TOPL properties. 3 is faster than both 1 and 2, by a good lot, and
doesn't require instrumenting the SIL code. Thus, delete 1 and 2!
Also harmonise the CLI so that TOPL is activated by --topl, which
actives it as a checker, like other analyses.
Reviewed By: rgrig
Differential Revision: D27270178
fbshipit-source-id: e86cf972b
Summary:
Changing model for Java `Collection` interface. Every collection has now two internal fields, initially set to `null`. We also keep an extra field to compute emptiness. This model was implemented based on the [preexisting model for HashMap](https://github.com/facebook/infer/blob/master/infer/models/java/src/java/util/HashMap.java).
Existing models (`add`, `remove`, `set` and `is_empty`) have been updated accordingly and new models are provided: `init` and `clear`.
This model is not yet compatible with the `Map` interface but this change will happen very soon.
Reviewed By: ezgicicek
Differential Revision: D27126815
fbshipit-source-id: 79a5fe306
Summary:
See updated tests and code comments: this changes many arithmetic
operations to detect when a contradiction "p|->- * p=0" is about to be
detected, and generate a latent issue instead. It's hacky but it does
what we want. Many APIs change because of this so there's some code
churn but the overall end result is not much worse thanks to monadic
operators.
Reviewed By: skcho
Differential Revision: D26918553
fbshipit-source-id: da2abc652
Summary: Although `Set.contains` could be logarithmic in the worst case, on average, the contains() runs in O(1) time. We rather take the average here, following the most common case.
Reviewed By: ngorogiannis
Differential Revision: D27078794
fbshipit-source-id: 24e3476e8
Summary:
`Initializer` annotation is an advanced feature that should be used
sparingly. Let's remove it from the error message and hence discourage
overuse
Reviewed By: ngorogiannis
Differential Revision: D27047431
fbshipit-source-id: 8eb7ba7ab
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:
Update Infer to LLVM (clang) 11.1.0.
Infer/clang now uses the LLVM 'monorepo' release, simplifying the download script.
Some changes done to how/when ASTExporter mangles names, this to avoid the
plugin hitting asserts in the clang code when mangling names.
Reviewed By: jvillard
Differential Revision: D27006986
fbshipit-source-id: 4d4b6ba05
Summary:
We use `procedure_name` which is coming from `Procname.get_method` in explanation of cost issues. For blocks, procedure name includes a prefix `objc_block` and a suffix with `_x` where x is the block counter. However, displaying this name to the user is not pretty. Especially when we have nested blocks, procedure name looks like `objc_blockobjc_blockdirectUIMessageFromContentAndMetadata_10_23`.
This diff drops the block index suffix and replaces `objc_block` with a prettier version `^`(signifying block).
so instead, in the cost report, we will have `^^blockdirectUIMessageFromContentAndMetadata`.
Reviewed By: skcho
Differential Revision: D26945333
fbshipit-source-id: 9d135423c
Summary: Variables captured by reference do not have correct type in objc blocks. They are missing one reference. This diff sets the correct type of captured reference variables inside procdesc, similarly as we already have for cpp lambdas. The translation of block's body will then take into account the type of captured variable from procdesc.
Reviewed By: ezgicicek
Differential Revision: D26945575
fbshipit-source-id: 06a9d9cc6
Summary: This diff adds a test replicating the issue fixed in D26975222 (7110c1ca3f) in [commit 7110c1c](7110c1ca3f)
Reviewed By: ngorogiannis
Differential Revision: D26978562
fbshipit-source-id: 41e41df8c
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:
RacerD needs to analyse the class initialiser in order to establish field properties in its post, such as that certain static fields are synchronized containers.
There was a bug where class initializers were not analysed at all, from the time where there was no analysis of field properties in the post.
We still don't want to report on the class initialiser since it cannot possibly race with itself (JVM guarantees that) and it cannot race with any of the other methods in its class (because it must finish before any other method can be called).
Reviewed By: da319
Differential Revision: D26887151
fbshipit-source-id: 570aff370
Summary: The `NonBlocking` annotation should zero out all domain elements that represent blocking calls. The current implementation only really removes such elements when they are generated by the current method under analysis, leaving such elements from callees unaffected. This diff fixes that.
Reviewed By: jvillard
Differential Revision: D26874704
fbshipit-source-id: 2d4859b30
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
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: Copying Java biabduction tests into pulse tests folder. The goal is to check how well Pulse will perform on Java.
Reviewed By: jvillard
Differential Revision: D25901299
fbshipit-source-id: a117b44f5
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
Summary: Renaming biabduction tests in infer/tests/codetoanalyze/java/biabduction/*.java to follow our naming convention: fooOk for tests where no report is expected, fooBad when we expect a report, and FP_ or FN_ prefixes when reality doesn't match the expectation
Reviewed By: jvillard
Differential Revision: D25900575
fbshipit-source-id: ad1370085
Summary:
D20769039 (cec8cbeff2) added a preanalysis step that creates edges from throw nodes to all reachable catch nodes. It intended to fix some deadstore FPs however it caused more damage than the fix itself. In particular, throws were connected irrespective of
- the type of the exception
- whether the try was surrounded by a catch
This in turn caused weird CFGs with dangling and impossible to understand nodes:(
This diff reverts this change for now.
Instead, the fix should probably be done in the frontend where we have more information about try/catch blocks.
Reviewed By: da319
Differential Revision: D25997475
fbshipit-source-id: bbeabfbef
Summary:
When there was an assignment of C struct, `x = y;`, it was translated to the statements of load and store.
```
n$0 = *y
*x = n$0
```
However, this is incorrect in Sil, because a struct is not a value that can be assigned to registers. This diff fixes the translation as assignments of each field values :
```
n$0 = *y.field1
*x.field1 = n$0
n$0 = *y.field2
*x.field2 = n$0
...
```
It copies field values of C structs on:
* assign statement
* return statement
* declarations.
It supports nested structs.
Reviewed By: jvillard
Differential Revision: D25952894
fbshipit-source-id: 355f8db9c
Summary:
Lambdas are essentially private (but are not marked as such in Infer),
so we should only report on their non-private callers.
Meanwhile, add a test to document that access propagation to those
callers is currently broken.
Reviewed By: da319
Differential Revision: D25944811
fbshipit-source-id: ef8ca6d9c
Summary:
This diff fixes a bug in the translation of an empty for-loop. When both initialization and
incrementation statements did not introduce a new node, the frontend generated an incorrect results
where the for-loop was unreachable from the entry node.
Fixes https://github.com/facebook/infer/issues/1374
Reviewed By: jvillard
Differential Revision: D25912142
fbshipit-source-id: 15b65cb84
Summary:
Previously, only names containing '$' were considered synthetic. We need
to extend the logic and look for "_UL_" in the name as well.
Also I deduped 4 different impls of "is_synthetic/generated/autogen".
Reviewed By: ngorogiannis
Differential Revision: D25899232
fbshipit-source-id: 9463eca6b
Summary:
When the body of the loop doesn't created a node then they don't get
wired correctly to the rest of the loop and end up dangling. Force node
creation to fix that.
Fixes https://github.com/facebook/infer/issues/1373
Reviewed By: ezgicicek
Differential Revision: D25804185
fbshipit-source-id: 85108bdd9
Summary:
We need to make sure a node is created to avoid instructions appearing
in the wrong order in the final CFG.
Reviewed By: da319
Differential Revision: D25784405
fbshipit-source-id: 3ef27d712
Summary: Model ` std::__optional_storage_base::has_value` as this is what we see in clang AST when translating `std::optional::has_value` for libc++. For libstdc++, we get `std::optional::has_value` as expected.
Reviewed By: skcho, jvillard
Differential Revision: D25585543
fbshipit-source-id: b8d9d2902
Summary:
The problem is that in `AnnotatedField.special_case_nullability` we
first check the _generic_ nullability and if it is `nonnullish` we
apply refinements for enums, synthetic fields, etc.
The problem is that the definition of `is_nonnullish` changed in
D25186043 (7dcbacf693) to a stricter one `UncheckedNonnull`, but generic
nullability stayed the same `ThirdPartyNonnull`.
Therefore enum elements were not considered `nonnullish` under
`--no-nullsafe-optimistic-third-party-in-default-mode` and the enum
refinements were not applied, which led to bogus errors.
**Example:**
There's a third-party enum
```
enum EnumClass {
ENUM_ELEMENT
}
```
`ENUM_ELEMENT` is represented as a private static field of
`EnumClass`.
Then we have first party code that does
```
EnumClass.ENUM_ELEMENT
```
If this first party class is not `Nullsafe` and the checker is ran
with `--no-nullsafe-optimistic-third-party-in-default-mode`, the user
gets an incorrect warning about `ENUM_ELEMENT` being unvetted third
party.
Reviewed By: ngorogiannis
Differential Revision: D25560119
fbshipit-source-id: 4ad0760c5
Summary:
Developers complain when a function that used to only throw an exception has complexity increase in the updated revision. Let's suppress such issues by giving those functions 0 cost which is already suppressed by differential reporting.
One common case to the above throw pattern is Java methods that throw an unsupported implementation exception for a functionality that has not been implemented yet. When the developer adds the supported implementation, we don't want to warn them with complexity increase since they are adding new functionality.
This is a design choice/heuristic to prevent noisy results for now.
Reviewed By: skcho
Differential Revision: D25495151
fbshipit-source-id: 94a82b062
Summary: This diff revises the trace generation of the uninitialized value checker, by introducing a new diagnostics for it.
Reviewed By: jvillard
Differential Revision: D25433775
fbshipit-source-id: 1279c0de4
Summary: This diff gives semantics of dispatch_sync to call the closure parameter.
Reviewed By: jvillard
Differential Revision: D25423175
fbshipit-source-id: a45309073
Summary:
This diff supports inter-procedural uninit analysis in pulse.
* Added `MustBeInitialized` attribute to pre state when an address is read
* Remove `Uninitialized` attribute when callee has `WrittenTo` for the
same address
Reviewed By: jvillard
Differential Revision: D25368492
fbshipit-source-id: cbc74d4dc
Summary:
Skipping the analysis of `std::vector::empty()` caused false positives: in the case where `std::vector::empty()` was called several times ("returning" different values each time), we were not able to prune infeasible paths.
Model `std::vector::empty()` as returning the same value every time it is called.
Reviewed By: ezgicicek
Differential Revision: D23904704
fbshipit-source-id: 52e8a2451
Summary:
Since D20736043 (d84fea52ae) is adding edges from the noreturn function node to exit node, analyzers should
handle the state differently to normal states.
Reviewed By: ezgicicek
Differential Revision: D25402576
fbshipit-source-id: a98e41b0c
Summary:
This diff adds uninitialized value check in pulse. For now, it supports only simple cases,
- declared variables with a type of integer, float, void, and pointer
- malloced pointer variables that points to integer, float, void, and pointer
TODOs: I will add more cases in the following diffs.
- declared/malloced array
- declared/malloced struct
- inter-procedural checking
Reviewed By: jvillard
Differential Revision: D25269073
fbshipit-source-id: 317df9a85
Summary:
This diff adds the ability to skip translation with `... && neg ( pattern)` logic so that we can skip translation of some files if the source does not contain a pattern.
Note that `skip-translation` expects a list of patterns as disjunctions:
https://www.internalfb.com/intern/diffusion/INFER/browse/master/infer/src/IR/inferconfig.ml?commit=76ae5fa0d3376573f6d04814e47ff6b5a9dd9746&lines=74
whereas we want the ability to have conjuctions inside.
## Context
Immutability analysis requires analyzing generated code which might have `Immutable` annotations. When analysing fbandroid, we skip all generated code:
```
"skip-translation": [
{
"source_contains": "generated",
"language": "Java"
}
],
```
However, rather than analyzing all generated code (which might be expensive across all targets) by removing the above, with this diff, we only analyze generated code that doesn't contain e.g. `Immutable` and skip all other generated code as before:
```
"skip-translation": [
{
"source_contains": "generated",
"source_not_contains": "Immutable",
"language": "Java"
}
],
```
Reviewed By: ngorogiannis
Differential Revision: D25328931
fbshipit-source-id: 3ae6ae92a
Summary:
The frontend of ObjC regarding to captured variable was incorrect: it set capturing mode as
by-reference always, but it actually translaged as if all captured variables were passed with
by-value. This diff fixes this based on the document.
https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Blocks/Articles/bxVariables.html
* global variable: by reference
* local variable: by value
* `static` local variable: by reference
* `__block` local variable: by reference
* parameter: by value
Reviewed By: jvillard
Differential Revision: D25306122
fbshipit-source-id: ec499d705
Summary:
When extracting summaries, ask PulseFormula to work harder to prove that
path-conditions are unsat. This reduces the number of false positives.
Reviewed By: jvillard
Differential Revision: D25270609
fbshipit-source-id: 61ef5e8ac
Summary:
Added a topl-max-disjuncts, which is analogous to pulse-max-disjuncts.
Note, however, that the maximum number of states tracked will be the
product of the two limits.
Added also topl-max-conjuncts, which drops Topl states that became too
complex.
Reviewed By: jvillard
Differential Revision: D25240386
fbshipit-source-id: 588c90390
Summary:
This diff adds a new issue type for reporting modifications to immutable fields (when `report-immutable-modifications` is enabled).
The underlying analysis depends on impurity analysis which itself is based on post-processing of pulse's summaries.
Reviewed By: skcho
Differential Revision: D25216637
fbshipit-source-id: 42e843793
Summary:
Previously, impurity analysis only collected one access for a single modification but not all other modifying accesses. This diff
- changes the impurity domain to collect all modifying accesses
- tracks and prints all the accesses seen to reach the modification, improving readability&debugging
Recording all accesses are needed in the next diff to determine if a method modifies any immutable fields. To determine that, we need to know all modifications, not just a single one.
Reviewed By: skcho
Differential Revision: D25186516
fbshipit-source-id: 43ceb3cd8
Summary: The main point here is to ignore owned interfaces when considering whether to warn about non-thread-safe calls.
Reviewed By: ezgicicek
Differential Revision: D25187775
fbshipit-source-id: c2a7ce89c
Summary: To look for captured variable address escape we should only check the validity of the addresses captured by reference. Checking the validity of the address captured by value can cause nullptr dereference false positives.
Reviewed By: jvillard
Differential Revision: D25219347
fbshipit-source-id: faf6f2b00
Summary:
For a long sequence of calls nop();...;nop() the runtime was quadratic
because formals and actuals were bound via equalities. Now,
substitutions are used, when easy.
Reviewed By: jvillard
Differential Revision: D25211504
fbshipit-source-id: 696e3dcdf
Summary:
If f() calls g() and g() violates a property, there used to be two
traces (one for f() and one for g()) even if all that f() has to do with
the property is that it calls g(). Now the error is reported only in
g().
Reviewed By: jvillard
Differential Revision: D25210007
fbshipit-source-id: 68ea57e71
Summary:
A "large step" is a call, and it is "trivial" if it does not affect the
automaton state; i.e., if it is irrelevant to the property being
tracked.
Reviewed By: jvillard
Differential Revision: D25209670
fbshipit-source-id: bf3e594b3
Summary:
Makes sure that topl summaries don't repeat. Previously this happened
when two posts led to the same summary when procedure-local variables
were killed. Such repeated summaries quickly lead to exponential
explosion. (For example, the added test -- `ManyLoops.java` -- didn't
finish in any reasonable time.)
Reviewed By: jvillard
Differential Revision: D25209623
fbshipit-source-id: 04b1a3e12
Summary:
Now one can use the pattern #ArrayWrite(A,I) to match on a write at
index I in array A. This only works in the Pulse variant of Topl (not in
the one based on SIL instrumentation).
Reviewed By: jvillard
Differential Revision: D25202768
fbshipit-source-id: 479f434e3
Summary:
PulseTopl.large_step is now implemented
All active tests are migrated now to topl-in-pulse.
Reviewed By: jvillard
Differential Revision: D25179556
fbshipit-source-id: dc1136bab
Summary:
When running the deep-Pulse version of Topl, it now produces and reports
traces.
Reviewed By: jvillard
Differential Revision: D25177139
fbshipit-source-id: 6955ee0cd
Summary:
This diff makes the issue to be rendered more clearly. Before, we used to report
weirdly looking unconventional mode names like NullsafeLocal, even when
exact mode name was irrelevant.
Reviewed By: artempyanykh
Differential Revision: D25186041
fbshipit-source-id: 2619bcbd2
Summary:
This diff adds trace of closure in autoreleasepool checker. We introduce a symbolic trace value for closure variable.
* It is added to the trace when closure variable is called
* and is substituted to concrete one when actual closure is given later.
Reviewed By: ezgicicek
Differential Revision: D25025883
fbshipit-source-id: a6e246be7
Summary:
Existing closure substitution only supported direct block calls to formals.
The following didn't work since the domain was only keeping track of loads/calls from formals, but didn't support stores.
```
void foo(dispatch_block_t block1){
dispatch_block_t local_block = block1;
local_block(); // we don't substitute the call here
}
```
This diff adds support for assigning a block to a local variable so that we can specialize the above example.
We now have a pair domain
- existing mapping from ids to block vars
- a new mapping from mangled to block specializations
the latter allows us to update the mapping in local block assignment (via store).
Reviewed By: skcho
Differential Revision: D25030234
fbshipit-source-id: 3f172341c
Summary:
Specialized closure substitution was broken for conditionals:
```
void foo(dispatch_block_t block1){
if (x){
block1(); // not replaced with specialized implementation
}
}
```
The problem was that when substituting function calls, it only used memory state at the exit node, rather than at each program point.
We could solve this by
- reverting the domain change in D24418560 (c47911359a), i.e. collecting all possible mappings conservatively (e.g. switch the domain back to `Map`)
- pass the `invariant_map` for substitutions at each program point.
We go with the second option here.
The closure substitution is still somewhat broken as exemplified by the following example:
```
void foo(dispatch_block_t block1){
dispatch_block_t local_block = block1;
local_block(); // we don't substitute the call here
}
```
Reviewed By: skcho
Differential Revision: D24993962
fbshipit-source-id: ebadddb58
Jules Villard
Ezgi Çiçek
Nikos Gorogiannis
Sungkeun Cho
Loc Le
Daiva Naudziuniene
Radu Grigore
Gabriela Cunha Sampaio
Mitya Lyubarskiy
Martin Trojer
Daniel Schoepe
Adam Ernst
Xiaoyu Liu
Artem Pianykh
Joscha Benz