Summary:
In main() all latent issues are manifest issues as the only parameters
are user-controlled.
Reviewed By: skcho
Differential Revision: D28121535
fbshipit-source-id: eab54d5bc
Summary:
As explained in the previous diff: when the access trace goes through
the invalidation step there is no need to print the invalidation trace
at all.
Note: only a few sources of invalidation are handled at the moment. The
following diffs gradually fix the other sources of invalidation.
Reviewed By: skcho
Differential Revision: D28098335
fbshipit-source-id: 5a5e6481e
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