Summary:
If an aggregate `a` has a field `f` whose type has a constructor (e.g., `std::string`), we translate creating a local aggregate `A { "hi" }` as `string(&(a.f), "hi")`.
This diff makes sure that we recognize this as initializing `a`.
Reviewed By: jeremydubreil
Differential Revision: D7404624
fbshipit-source-id: 0ba90a7
Summary:
Show where the invalidation occurred in the trace.
Should make things easier to understand.
Reviewed By: jeremydubreil
Differential Revision: D7312182
fbshipit-source-id: 44ba9cc
Summary: It adds an issue type, `BUFFER_OVERRUN_U5`, for alarms involving unknown values, i.e., when the trace set includes an unknown function call.
Reviewed By: mbouaziz
Differential Revision: D7178841
fbshipit-source-id: bfe857b
Summary:
Aggregate initialization (e.g., `S s{1, 2}`) doesn't invoke a contructor.
Our frontend translates aggregation initialization as assigning to each field in the struct.
To avoid the appearance of the struct being uninitialized, count any assignment to a field of an aggregate struct as initializing the struct.
Reviewed By: jeremydubreil
Differential Revision: D7189671
fbshipit-source-id: ace02fc
Summary:
Show some `SymAssign`s (corresponding to parameters) in the trace.
Depends on D7194448
Reviewed By: skcho
Differential Revision: D7194479
fbshipit-source-id: 0deff6c
Summary: It simply resizes the target structure instead of allocating new heap memories and copying values.
Reviewed By: mbouaziz
Differential Revision: D7179353
fbshipit-source-id: 9c20f64
Summary: If a `Closure` expression `e` captures variable `x`, consider `e` as borrowing from `x`. When the closure is invoked via `operator()`, check that the borrow is still valid.
Reviewed By: jeremydubreil
Differential Revision: D7071839
fbshipit-source-id: d923a6a
Summary: It collects array accesses from all sub expressions in commands.
Reviewed By: mbouaziz
Differential Revision: D7165098
fbshipit-source-id: 584dc80
Summary: It does not only malloc a new heap memory, but also copy its contents.
Reviewed By: mbouaziz
Differential Revision: D7152194
fbshipit-source-id: 58cba5e
Summary: This is to make sure than the analysis produces the same results independently from the order in which the members of a call cycle are analyzed.
Reviewed By: sblackshear, mbouaziz
Differential Revision: D6881971
fbshipit-source-id: 23872e1
Summary:
Fairly simple approach here:
- If the RHS of an assignment is a frontend-generated temporary variable, assume it transfers ownership to the LHS variable
- If the RHS of an assignment is a program variable, assume that the LHS variable is borrowing from it.
- If we try to access a variable that has borrowed from a variable that is now invalid, complain.
Reviewed By: jeremydubreil
Differential Revision: D7069947
fbshipit-source-id: 99b8ee2
Summary:
At function calls, it copies a subset of heap memory that is newly
allocated by callees and is reachable from the return value.
Reviewed By: mbouaziz
Differential Revision: D7081425
fbshipit-source-id: 1ce777a
Summary:
Before D7100561, the frontend translated capture-by-ref and capture-by-value in the same way.
Now we can tell the difference and report bugs in the capture-by-value case.
Reviewed By: jeremydubreil
Differential Revision: D7102214
fbshipit-source-id: e9d3ac7
Summary:
The `may_last_field` boolean value in the `decl_sym_val` function presents that the location *may* (not *must*) be a flexible array member.
By the modular analysis nature, it is impossible to determine whether a given argument is a flexible array member or not---because of lack of calling context. For example, there are two function calls of `foo` below: (2) passes a flexible array member as an argument and (1) passes a non-flexible array, however it is hard to notice when analyzing the `foo` function.
```
struct T {
int c[1];
};
struct S {
struct T a;
struct T b;
};
void foo(struct T x) { ... }
void goo () {
struct S* x = (struct S*)malloc(sizeof(struct S) + 10 * sizeof(int));
foo(&(x->a)); // (1)
foo(&(x->b)); // (2)
}
```
We assume that any given arguments may stem from the last field of struct, i.e., flexible array member. (This is why `decl_sym_val` is called with `may_last_field:true` at the first time.) With some tests, we noticed that the assumption does not harm the analysis precision, because whether regarding a parameter as a flexible array member or not is about using a symbolic array size instead of a constant array size written in the type during the analysis of callee. Therefore still it can raise correct alarms if the actual parameter is given in its caller.
Reviewed By: mbouaziz
Differential Revision: D7081295
fbshipit-source-id: a4d57a0
Summary:
Switch to the current stable branch for clang.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D7067890
fbshipit-source-id: aedff90
Summary:
You can capture a variable by reference in a lambda, assign to it, and then invoke the lambda.
This looks like a dead store from the perspective of the current analysis.
This diff mitigates the problem by computing an additional analysis that tracks variables captured by ref at each program point.
It refuses to report a dead store on a variable that has already been captured by reference.
Later, we might want to incorporate the results of this analysis directly into the liveness analysis instead of just using it to gate reporting.
Reviewed By: jeremydubreil
Differential Revision: D7090291
fbshipit-source-id: 25eeffa
Summary:
It supports flexible array member using the following heuristic:
- a memory for a class is allocated by `malloc(sizeof(C) + n * sizeof(T))` format
- the last field of the class is an array
- the static size of the last field is one, i.e., `T field_name[1]`
When allocating and initializing members of classes, it sets the size of flexible array to `n+1` if the above conditions are met.
Reviewed By: mbouaziz
Differential Revision: D7056291
fbshipit-source-id: 31c5868
Summary:
The semantics of "placement new" is defined simply as an assignment.
For example, `C* x = new (y) C();` is analyzed as if `C* x = y;`.
Reviewed By: mbouaziz
Differential Revision: D7054007
fbshipit-source-id: 1c6754f
Summary:
The struct fields in Cil have been sorted for long time, however the
checkers do not seem to depend on the sortedness.
Reviewed By: sblackshear
Differential Revision: D7027858
fbshipit-source-id: 9e7ab96
Summary:
This commit improves precision of symbol instantiations.
When a return value of a callee is `[s1 + s2, _]` and if we want to
instantiate `s1` to `c3 + max(c4, s5)`, the lower bound was
substituted to `-oo` because our domain cannot express `c3 + max(c4,
s5) + s2`.
However, we can have instantiations that are preciser than `-oo`:
(1) `c3 + c4 + s2`
(2) or `c3 + s5 + s2`
because they are smaller than the ideal instantiation, `c3 + max(c4,
s5) + s2` and it is on the lower bound position.
For now, the implementation instantiates to (1) between the two ones,
because constant values introduced by `assert` or `assume`(`if`)
command are often used as safety conditions, e.g., `assert(index >=
0);` can place before array accesses. (We can change the stratege
later if we find that it doesn't work on some other cases.)
Reviewed By: mbouaziz
Differential Revision: D7020063
fbshipit-source-id: 62fb390
Summary:
A simple intraprocedural analysis that tracks when a storage location is read or deleted.
For now, this works only with local variable storage locations; field and array accesses are ignored.
In order to test this, I added a new "use-after-lifetime" warning. It complains when a variable is read or deleted after it has already been deleted.
Reviewed By: jeremydubreil
Differential Revision: D6961314
fbshipit-source-id: 75e95a2
Summary: We do not inject a destructor call if the destructor declaration does not contain a body in AST. We miss all the cases where the destructor is declared in `.h` file and defined in `.cpp` file as other files include `.h` file and do not contain the body of the destructor when destructor calls are being injected based on AST information. After this diff we inject destructor calls even if we do not have body for the destructor in AST.
Reviewed By: sblackshear
Differential Revision: D6796567
fbshipit-source-id: 1c187ec
Summary:
It prunes abstract memories on `assert` commands.
Problem: Since the assert command is sometimes translated to two
sequential `if` statments, it was not able to prune the memory
precisely at `assert` commands in Inferbo---the pruned memory at the
first branch was joined before the second branch.
Solution: To avoid losing the pruning information at the first branch,
now, it records which locations are pruned at the first branch and
applies the same pruning at the next branch if they have
semantically the same condition.
Reviewed By: mbouaziz
Differential Revision: D6895919
fbshipit-source-id: 15ac1cb
Summary: In Obj-C blocks, we explicitly insert reads of the captured vars. This does the same thing for C++. For example, `foo() { int x = 1; [x]() { return x; } }` would previously not contain a read of `x` in `foo`. Now, we'll create a temporary that reads from `x` and pass it to the closure value.
Reviewed By: dulmarod
Differential Revision: D6939997
fbshipit-source-id: f218afc
Summary:
Added a check for recursive calls not to add abduced reference parameters constraints. Abduced reference parameters constraints were causing assertion failure when renaming variables in specs, in particular, when transforming variables into callee variables.
A similar check is already in place for abduced retvals constraints.
Reviewed By: jeremydubreil
Differential Revision: D6856919
fbshipit-source-id: acfe840
Summary:
The boolean lock domain is simple and surprisingly effective.
But it's starting to cause false positives in the case where locks are nested.
Releasing the inner lock also releases the outer lock.
This diff introduces a new locks domain: a map of locks (access paths) to a bounded count representing an underapproximation of the number of times the lock has been acquired.
For now, we just use a single dummy access path to represent all locks (and thus a count actually would have been sufficiently expressive; we don't need the map yet).
But I'm planning to remove this limitation in a follow-up by refactoring the lock models to give us an access path.
Knowing the names of locks could be useful for error messages and suggesting fixes.
Reviewed By: jberdine
Differential Revision: D6182006
fbshipit-source-id: 6624971
Summary:
This diff fixes the translation of `new` and `placement new` with one argument. If `placement new` has more than one argument it means that it is user-defined (this will be addressed in another diff).
update-submodule: facebook-clang-plugins
Reviewed By: sblackshear, mbouaziz
Differential Revision: D6807751
fbshipit-source-id: 7cf0290
Summary: This should allow to report several occurences of the an issue appearing several times within the same method.
Reviewed By: jvillard
Differential Revision: D6783298
fbshipit-source-id: 5555906
Summary:
Not sure what an "iCFG" is but the dotty is only about CFGs anyway.
Diff obtained by mass-`sed`.
Reviewed By: sblackshear
Differential Revision: D6324280
fbshipit-source-id: b7603bb
Summary:
In Java, static variables are distinguished by package/class:
the file where they are defined doesn't matter.
Fixes#831.
Closes https://github.com/facebook/infer/pull/833
Reviewed By: jeremydubreil
Differential Revision: D6661240
Pulled By: sblackshear
fbshipit-source-id: beeb2f9
Summary: Previously we had a single sanitizer kind for escaping, but this isn't quite right. A function that escapes a URL doesn't necessarily make a string safe to execute in SQL, for example.
Reviewed By: the-st0rm
Differential Revision: D6656376
fbshipit-source-id: 572944e
Summary:
Model for `folly::split` that handles the representation in the cpp model.
Depends on D6544992
Reviewed By: jvillard
Differential Revision: D6545006
fbshipit-source-id: 2b7a139
Summary: This is to allow the bi-abduction analysis and the nullable checker for Clang languages to run together without stepping on each other toes.
Reviewed By: sblackshear
Differential Revision: D6567934
fbshipit-source-id: a318c33
Summary: As Dulma pointed out, adding or removing paramters in a method in Objective C is changing the name of the method. Such changes should not make pre-exisiting issues reported as introduced. This diff is to prevent this by only keeping in the bug hash the part of the name that is before the first colon.
Reviewed By: dulmarod
Differential Revision: D6491215
fbshipit-source-id: 3c00fae
Summary:
Our model of unique_ptr and shared_ptr relied on the fact that we could C-style cast a pointer to the internal pointer type used in the smart pointer.
This is wrong when the smart pointer is used with a custom deleter that declares its own pointer type whose is not constructible from just a single pointer.
Reviewed By: dulmarod
Differential Revision: D6496203
fbshipit-source-id: 1305137
Summary: This will avoid collisions when the inner classes are implementing the same methods. For example, the previous version of the bug hash could conflate the issues when several annonymous inner classes are implementing the same method, e.g. a annonymous subclass of `Runnable` implementing `run()`.
Reviewed By: sblackshear
Differential Revision: D6461594
fbshipit-source-id: 2bb8545
Summary:
Simpler bug hash that is more independent of the underlying analysis. This now computes the hash based on:
- the bug type.
- the base filename: i.e for my/source/File.java, just keep File.java. So the hash will not change when moving files around.
- the simple method name: i.e. without package information and list of parameters. So changing the list of parameters will not affect the bug hash.
- the error message were the line numbers have been removed. So moving code or reformatting will not affect the hash.
Reviewed By: jberdine
Differential Revision: D6445639
fbshipit-source-id: 82e3cbe
Summary: To avoid false positives, we treat `operator[]` in cpp as container read. Moreover, if a container `c` is owned, we make all accesses `c[i]` to be also owned.
Reviewed By: sblackshear
Differential Revision: D6396574
fbshipit-source-id: 94aabff
Summary:
It seems that the abstraction instructions were not previously added the the CFG.
This is a functional changes to make sure that the abstraction state is always added. We can simplify the code later and just run this step before storing the CFG instead of after loading them.
Reviewed By: sblackshear, jvillard
Differential Revision: D6383672
fbshipit-source-id: cedcb8a
Summary:
As da319 points out, we did not handle this case correctly before. There were a few reasons why:
(1) An assignment like `struct S s = mk_s()` gets translated as `tmp = mk_s(); S(&s, tmp)`, so we didn't see the write to `s`.
(2) We counted uses of variables in destructors and dummy `_ = *s` assignments as reads, which meant that any struct values were considered as live.
This diff fixes these limitations so we can report on dead stores of struct values.
Reviewed By: da319
Differential Revision: D6327564
fbshipit-source-id: 2ead4be
Summary:
This resolves#796 . Effectively it adds file specific suffix to name of all global initializers (so initializersof two global variable of the same name will have unique Typ.Procname). which is the same rule as currently used by constructing Procname for the static functions. However this change applies to initializers of all global variables and not just static (arguably it's a right thing. since GCC used to allow multiple global variables with the same name).
Consequences of this change that it becomes impossible to know name of generated initialization function of global ('extern') variables. However get_initializer_pname function is only referenced by the frontend (when creating initializer for the defined global variables) and by the SIOF checker.
Closes https://github.com/facebook/infer/pull/801
Reviewed By: jvillard
Differential Revision: D6335034
Pulled By: dulmarod
fbshipit-source-id: 1a92c08
Summary: The clang compiler introduces a materialized temporary expression which should be treated similarly to the Infer internal temporary variables.
Reviewed By: sblackshear
Differential Revision: D6331237
fbshipit-source-id: 81d8196
Summary:
We would previously skip any function that had one of these.
A no-op translation is sufficient to fix this issue (see new E2E test).
Reviewed By: mbouaziz
Differential Revision: D6317323
fbshipit-source-id: 0855bd8
Summary: Just changing ClangTrace to actually look at the different sanitizer kinds.
Reviewed By: jeremydubreil
Differential Revision: D6325086
fbshipit-source-id: 5da236d
Summary: In a thread safety report we used the access path from the final sink. This diffs change the report to include the expanded access path from the initial sink.
Reviewed By: sblackshear
Differential Revision: D6297848
fbshipit-source-id: 2386063
Summary: The checker should not report unitinialzed values on the throw branch.
Reviewed By: ddino
Differential Revision: D6267019
fbshipit-source-id: 05768f1
Summary: We were conflating reads/writes with container reads/writes that created false positives.
Reviewed By: sblackshear
Differential Revision: D6232768
fbshipit-source-id: 39159cb
Summary: This is a hack to removes most of the false positives of this checker in Objective C.
Reviewed By: sblackshear
Differential Revision: D6239914
fbshipit-source-id: 1cf05de
Summary:
This confuses the SIOF checker and causes false positives. This dummy deref is
generated for constructors of classes that are modeled as being pointer types
instead of the actual class in infer, typically for smart pointers. I do not
understand how this works.
The biabduction also analyses this code, so might now get confused itself.
Reviewed By: jberdine
Differential Revision: D6221817
fbshipit-source-id: 050c5a9
Summary:
The issue is with classes defining static data members:
```
$ cat foo.h
struct A {
static int foo;
};
$ cat foo.cpp
#include "foo.h"
int A::foo = 12;
int f() { return A::foo; // should see A::foo as defined in this translation unit
$ cat bar.cpp
#include "foo.h"
void g() { return A::foo; // should see A::foo defined externally
```
Previously, both foo.cpp and bar.cpp would see `A::foo` as defined within their
translation unit, because it comes from the header. This is wrong, and static
data members should be treated as extern unless they're defined in the same
file.
This doesn't change much except for frontend tests. SIOF FP fix in the next diff.
update-submodule: facebook-clang-plugins
Reviewed By: da319
Differential Revision: D6221744
fbshipit-source-id: bef88fd
Summary: The checker should not report nullable violations on repeated calls
Reviewed By: sblackshear
Differential Revision: D6195471
fbshipit-source-id: 16ff76d
Summary: Functions that do not belong to a class or a struct are translated to c-style functions even in the context of cpp. We need to add ownership to locals for c-style functions too.
Reviewed By: sblackshear
Differential Revision: D6196882
fbshipit-source-id: 715f129
Summary:
vector::data returns a pointer to the first value of the vector.
- The size of the (array) pointer should be the same with the vector.
- The pointer should point to the same abstract value with the vector.
Reviewed By: mbouaziz
Differential Revision: D6196592
fbshipit-source-id: cc17096
Summary: `std::unique_lock` constructor allows to create a unique lock without locking the mutex. `std::unique_lock::try_lock` returns true if mutex has been acquired successfully, and false otherwise. It could be that an exception is being thrown while trying to acquire mutex, which is not modeled.
Reviewed By: jberdine
Differential Revision: D6185568
fbshipit-source-id: 192bf10
Summary:
Code often uses std::unique_lock::owns_lock to test if a deferred lock
using the 2-arg std::unique_lock constructor actually acquired the
lock.
Reviewed By: sblackshear
Differential Revision: D6181631
fbshipit-source-id: 11e9df2
Summary:
Use a distinct issue type for the Java and C++ concurrency analyses,
as the properties they are checking are significantly different.
Reviewed By: sblackshear
Differential Revision: D6151682
fbshipit-source-id: 00e00eb
Summary:
In a summary, you never want to see a trace where non-footprint sources flow to a sink.
Such a trace is useless because nothing the caller does can make more data flow into that sink.
Reviewed By: jeremydubreil
Differential Revision: D5779983
fbshipit-source-id: d06778a
Summary: In HIL, allow deref'ing a magic address like `0xdeadbeef` for debugging purposes. Previously, we would crash on code like this.
Reviewed By: mbouaziz
Differential Revision: D6143802
fbshipit-source-id: 4151924
Summary: This check is deprecated and will be replaced by a dedicated checker to detect unitialized values.
Reviewed By: mbouaziz
Differential Revision: D6133108
fbshipit-source-id: 1c0e9ac
Summary: Previously, this would incorrectly classify types like `map<std::string, int>` as a buffer
Reviewed By: mbouaziz
Differential Revision: D6125530
fbshipit-source-id: c8564de
Summary:
Refactor `RegisterCheckers` to give a record type to checkers instead of a tuple type.
Print active checkers with their per-language information.
Improve the manual entries slightly.
Reviewed By: sblackshear
Differential Revision: D6051167
fbshipit-source-id: 90bcb61
Summary: This commit adds unsigned symbol for preciser analysis results with less number of uses of min/max operators.
Reviewed By: mbouaziz
Differential Revision: D6040437
fbshipit-source-id: 999ca4c
Summary:
1. Mark some Makefile targets as depending on `MAKEFILE_LIST` so they get rebuilt on Makefile changes
2. Do not show boolean options with no documentation in the man pages (like we do for other option types).
3. Default to Lazy dynamic dispatch for the checkers.
4. In the tests, use `--<checker>-only` instead of relying on `--no-default-checkers`
5. `--no-filtering` is redundant if `--debug-exceptions` is passed
Reviewed By: jeremydubreil
Differential Revision: D6030578
fbshipit-source-id: 3320f0a
Summary: Stack-allocated variables cannot be raced on in cpp as every thread has its own stack. At the beginning of the analysis we add ownership to the local variables.
Reviewed By: jberdine
Differential Revision: D6020506
fbshipit-source-id: 0a90a97
Summary: Now that we report write-write races involving more than one write, we need to improve the traces accordingly.
Reviewed By: jberdine
Differential Revision: D6026845
fbshipit-source-id: b1366dd
Summary:
Next step to issue deduplication: do not keep safety conditions that are subsumed by others.
Only do it if they do not have infinite bound: replacing `0 < size` by `1 < size` is ok, but replacing it by `+oo < size` is not because it looks much more like a lack of precision.
Reviewed By: skcho
Differential Revision: D5978455
fbshipit-source-id: acc2384
Summary:
A specific type of alias is added for the vector::empty() result and it is used at pruning.
Now, there are two types of aliases:
- "simple" alias: x=y
- "empty" alias: x=v.empty() and y=v.size
So, if x!=0, y is pruned by (y=0). Otherwise, i.e., x==0, y is pruned by (y>=1).
Reviewed By: mbouaziz
Differential Revision: D6004968
fbshipit-source-id: bb8d50d
Summary:
Attempting to translate these will not go well as the declaration still depends
on some template arguments. Added a test that was previously crashing the
frontend.
Also extend the catching of "Unimplemented" and other errors to `translate_one_decl` as it was useful to debug this issue. In particular, reraise all exceptions and log some additional context when doing so.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D5976357
fbshipit-source-id: fca8e38
Summary:
Indicate if read or write is protected, and do not print only the
field but also the object involved in the race.
Reviewed By: sblackshear
Differential Revision: D5974250
fbshipit-source-id: 351a576
Summary:
Inject a marker using a global variable in <iostream>, and whitelist it so that
the frontend translates it.
Use the marker in the SIOF checker to tell whether a file includes <iostream>.
If so, start the analysis of its methods assuming that the standard streams are
initialised.
Reviewed By: sblackshear
Differential Revision: D5941343
fbshipit-source-id: 3388d55
Summary:
The previous domain for SIOF was duplicating some work with the generic Trace
domain, and basically was a bit confused and confusing. A sink was a set of
global accesses, and a state contains a set of sinks. Then the checker has to
needlessly jump through hoops to normalize this set of sets of accesses into a
set of accesses.
The new domain has one sink = one access, as suggested by sblackshear. This simplifies
a few things, and makes the dedup logic much easier: just grab the first report
of the list of reports for a function.
We only report on the fake procedures generated to initialise a global, and the
filtering means that we keep only one report per global.
Reviewed By: sblackshear
Differential Revision: D5932138
fbshipit-source-id: acb7285
Summary: The tests are slower when running in debug mode, and it creates a lot of html outputs
Reviewed By: sblackshear
Differential Revision: D5916511
fbshipit-source-id: 07c90b7
Summary:
This diff does two things:
# Infer no longer add the contrains that the return value of a skip function is never null. This was leading to false negatives and is not necessary as those return value are treated angelically
# Infer now support `Nonnull` on the return value of skip functions.
Reviewed By: jberdine, sblackshear
Differential Revision: D5840324
fbshipit-source-id: bbd8d82
Summary: Example of combination between annotating fields with nullable and the biabduction analysis in Objective C
Reviewed By: dulmarod
Differential Revision: D5906016
fbshipit-source-id: b95c6e0
Summary:
The interval bound of the abstract domain is extended.
`[min|max](int, symbol)` => `int [+|-] [min|max](int, symbol)`
As a result, `vector::empty` can be modelled to return a more precise value: `1 - min(1, size)`.
Reviewed By: mbouaziz
Differential Revision: D5899404
fbshipit-source-id: c8c3f49
Summary:
With this change and the previous facebook-clang-plugins change, infer no
longer exhausts the biniou buffer when reading the serialized C++ AST.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D5891081
fbshipit-source-id: cf48eac
Summary:
Since D5381239, infer is careful not to delete directories that do not "look
like" results directories on startup, in case the user passed, eg, `-o /`.
In our repo, lots of results dir are created by build/test of infer, and when
the version of infer changes and the expected contents of results directories
change then it might start refusing to delete the results directories created
with another version of infer.
Add an option to force infer to delete the results directory no matter how
dodgy it looks, and use it in our repo by adding the option in every
.inferconfig.
Reviewed By: mbouaziz
Differential Revision: D5870984
fbshipit-source-id: 09412de
Summary: Will then be easier to understand if some changes in the test results is legit or not.
Reviewed By: sblackshear
Differential Revision: D5863961
fbshipit-source-id: 7eb3f33
Summary:
Suggesting to add `_Nullable` on the fields checked for, or assigned to, `nullptr` will allow the biabduction analysis to report null dereferences that are related to the lifetime of objects.
Depends on D5832147
Reviewed By: sblackshear
Differential Revision: D5836538
fbshipit-source-id: c1b8e48
Summary: The prune nodes where translated as `prune (expr = false)` and `prune ( expr != false)`. This case is a bit tricky to deconstruct in HIL. This diff translates the prune instructions as just `prune !expr` for the true branch and `prune expr` for the false branch.
Reviewed By: dulmarod
Differential Revision: D5832147
fbshipit-source-id: 2c3502d
Summary:
We need to make sure that destructors of virtual base classes are called only once. Similarly to what clang does, we have two destructors for a class: a destructor wrapper and an inner destructor.
Destructor wrapper is called from outside, i.e., when variables go out of scope or when destructors of fields are being called.
Destructor wrappers have calls to inner destructors of all virtual base classes in the inheritance as their bodies.
Inner destructors have destructor bodies and calls to destructor wrappers of fields and inner destructors of non-virtual base classes.
Reviewed By: dulmarod
Differential Revision: D5834555
fbshipit-source-id: 51db238
Summary:
The "placement new" operator `new (e) T` constructs a `T` in the pre-allocated memory address `e`.
We weren't translating the `e` part, which was leading to false positives in the dead store analysis.
Reviewed By: dulmarod
Differential Revision: D5814191
fbshipit-source-id: 05c6fa9
Summary:
Simple instance of the problem: analyzing the following program times out.
```
#include <tuple>
void foo() {
std::tuple<std::tuple<int>> x;
}
```
Replacing `std::tuple<std::tuple<int>>` by `std::tuple<int>` makes the analysis
terminate.
In the AST, both tuple<tuple<int>> and tuple<int> have the same template
specialization type: "Pack" (which means we're supposed to go look into the
arguments of the template to get their values). This is not information enough
and that's the plugin fault.
On the backend side, this means that two types have the same Typ.Name.t, namely
"std::tuple<_>", so they collide in the tenv. The definition of
tuple<tuple<int>> is the one making it into the tenv. One of the fields of the
corresponding CxxRecord is of type "tuple<int>", which we see as the same
"tuple<_>", which causes the loop.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D5775840
fbshipit-source-id: 0528604
Summary: Destroying local variables that are out of scope after `continue`.
Reviewed By: jberdine
Differential Revision: D5804120
fbshipit-source-id: 638cff5
Summary: Destroying local variables that are out of scope after `break`.
Reviewed By: jberdine
Differential Revision: D5764647
fbshipit-source-id: a7e06ae
Summary: The successor node of `continue` was not correct inside the `do while`.
Reviewed By: sblackshear
Differential Revision: D5769578
fbshipit-source-id: d7b0843
Summary:
We supported globals as sources before, but we did so by allowing ClangTrace etc. to match against any access path in the footprint of the trace.
This is very powerful/flexible, but it's ultimately not a good idea because it leads to traces that are hard to read.
This is because a footprint source doesn't have any information about its provenance: we might know that the value came from a global, but we don't know where the read occurred.
The mechanism for handling procedure calls as sources already knows how to solve this problem.
This diff implements globals as sources as a special case of procedure call sources instead.
This will give us much nicer traces with full provenance of the read from the global.
Reviewed By: mbouaziz
Differential Revision: D5772299
fbshipit-source-id: 491ae81
Summary:
When a lambda has an `auto` parameter, the inferred type of the parameter because part of the name.
Our heuristic for identifying lambda was checking if the lambda's name was exactly `operator()`, which won't catch this case.
Reviewed By: jvillard
Differential Revision: D5753323
fbshipit-source-id: 85ff75a
Summary:
Not translating these properly was causing false positives for the dead store analysis in cases like
```
int i = 0;
return [j = i]() { return j; }();
```
Reviewed By: da319
Differential Revision: D5731562
fbshipit-source-id: ae79ac8
Summary: We inject destructor calls of base classes inside destructor bodies after the destructor calls of fields.
Reviewed By: dulmarod
Differential Revision: D5745499
fbshipit-source-id: 90745ec
Summary: We used to crash whenever we hit these. The simple translation implemented here is not particularly inspiring, but it is better than crashing.
Reviewed By: jvillard
Differential Revision: D5702095
fbshipit-source-id: 3795d43
Summary: This makes the traces more readable when involving skipped functions.
Reviewed By: sblackshear
Differential Revision: D5731683
fbshipit-source-id: 49d363b
Summary:
In looking at summaries that Quandary took a long time to compute, one thing I notice frequently is redundancy in the footprint sources (e.g., I might see `Footprint(x), Footprint(x.f), Footprint(x*)`).
`sudo perf top` indicates that joining big sets of sources is a major performance bottleneck, and a large number of footprint sources is surely a big part of this (since we expect the number of non-footprint sources to be small).
This diff addresses the redundancy issue by using a more complex representation for a set of sources. The "known" sources are still in a set, but the footprint sources are now represented as a set of access paths (via an access trie).
The access path trie is a minimal representation of a set of access paths, so it would represent the example above as a simple `x*`.
This should make join/widen/<= faster and improve performance
Reviewed By: jberdine
Differential Revision: D5663980
fbshipit-source-id: 9fb66f8
Summary:
The previous widening operator added stars to the *end* of paths that existed in `next` but not `prev`. This is not enough to ensure termination in the case where the trie is growing both deeper and wider at the same time.
The newly added test demonstrates this issue. In the code, there's an ever-growing path of the form `tmp.prev.next.prev.next...` that wasn't summarized by the previous widening operator. The new widening is much more aggressive: it replaces *any* node present in `next` but not `prev` with a `*` (rather than trying to tack a star onto the end). This fixes the issue.
This issue was causing divergence on tricky doubly-linked list code in prod.
Reviewed By: jeremydubreil
Differential Revision: D5665719
fbshipit-source-id: 1310a92
Summary:
This makes it easier to test a single checker.
Also refactor the code to make it harder to mess up the list of default/all checkers.
Reviewed By: sblackshear
Differential Revision: D5583209
fbshipit-source-id: 7c919b2
Summary:
Previous version was hard to understand because it was doing many things within same code. New version has different code for Arrays, Structs and others.
There is some copy-paste, but it's easier to follow code (open to suggestions though)
Reviewed By: dulmarod
Differential Revision: D5547999
fbshipit-source-id: 77ecb24
Summary: It wasn't using code from `std::vector::empty` which recently was improved. Instead of inlining `std::vector::empty`, call it to know whether vector is empty or not.
Reviewed By: jvillard
Differential Revision: D5573379
fbshipit-source-id: e024a42
Summary: Useful for identifying user-controlled array accesses that could lead to buffer overflows
Reviewed By: mbouaziz
Differential Revision: D5520985
fbshipit-source-id: 92984f6
Summary:
With current model, there are issues with cxx range loop. It looks like
it comes from std::vector::size model.
example of such FP:
```
int t = vec.size();
for(auto& elem : vec) {
auto x = elem
}
```
Reviewed By: jvillard
Differential Revision: D5545914
fbshipit-source-id: fbe55b3
Summary: Those are not particularly relevant for the biabduction analysis. It would be easy to have a dedicated checker for this if we happen to need one day.
Reviewed By: sblackshear
Differential Revision: D5530834
fbshipit-source-id: 316e60f
Summary:
Bumps facebook-clang-plugins to a version that outputs sizeof() info in bytes and not bits.
update-submodule: facebook-clang-plugins
Reviewed By: akotulski
Differential Revision: D5526747
fbshipit-source-id: 6019542
Summary: The `--failures-allowed` was doing for the Clang frontend what `--keep-doing` was doing for the backend. This revision merges the two options to simplify the Infer CLI and our tests.
Reviewed By: jvillard
Differential Revision: D5474347
fbshipit-source-id: 09bcea4
Summary:
update-submodule: facebook-clang-plugins
Moving to a newer version of clang, see ffb5dd0114
Reviewed By: jvillard
Differential Revision: D5452529
fbshipit-source-id: 28bc215
Summary:
Pretty basic: warn when we see an assignment instruction `x = ...` and `x` is not live in the post of the instruction.
Only enabled for Clang at the moment because linters already warn on this for Java. But we can enable it later if we want to (should be fully generic).
Reviewed By: jeremydubreil
Differential Revision: D5450439
fbshipit-source-id: 693514c
Summary:
This commit avoids precision loss on pruning.
// x -> [s$1, s$2]
if(x) { ... }
// x -> ?
before: x -> [min(0, s$1), max(0, s$2)]
because two x values, [0, 0] (true case) and [s$1, s$2] (false case), were joined after the if branch.
after: x -> [s$1, s$2]
Reviewed By: mbouaziz
Differential Revision: D5431009
fbshipit-source-id: 14a9efe
Summary:
Problem: The analyzer did not know that the value of `v.size()` is an alias of `v.infer_size`, so `v.infer_size` is not pruned by the if condition. As a result it raises a false alarm.
void safe_access(std::vector<int> v) {
if (v.size() >= 10) {
v[9] = 1; // error: BUFFER_OVERRUN Offset: [9, 9] Size: [5, 5]
}
}
void call_safe_access_Good() {
std::vector<int> v(5, 0);
safe_access(v);
}
Solution: Adding alias for return value to the abstract domain.
Now Inferbo can prune `v.infer_size` because it knows that the value of `v.size()` is an alias of `v.infer_size`. There is already an alias domain in Inferbo, so we added a specific room for the retrun value.
Reviewed By: jvillard, mbouaziz
Differential Revision: D5396988
fbshipit-source-id: 4a4702c
Summary:
:
because otherwise people would believe they can use the internal representation of these std lib but it fails for our models.
Reviewed By: jvillard
Differential Revision: D5368671
fbshipit-source-id: 4e53d5a
Summary:
:
Get rid of model location in reports.
The goal is to avoid changing `issues.exp` whenever a model is updated.
Reviewed By: jvillard
Differential Revision: D5356608
fbshipit-source-id: 88ecaba
Summary:
Indexing into a string literal expression would generate a fresh
variable on every application of a transformer. This violated
finiteness of the domain, and caused divergence.
Reviewed By: da319
Differential Revision: D5342951
fbshipit-source-id: e95e84e
Summary:
It instantiates fields of structures when a pointer to which is given
as a function parameter, e.g., `foo(&s);`.
Reviewed By: mbouaziz, jvillard
Differential Revision: D5337645
fbshipit-source-id: c06da29
Summary:
We keep track of both `beginPtr` and `endPtr` but the modelling was mostly
about `beginPtr` as some sort of approximation I guess. This shouldn't change
much but will be useful later when doing more iterator stuff.
Reviewed By: mbouaziz
Differential Revision: D5255772
fbshipit-source-id: 0f6e3e8
Summary: This seems to move in the right direction. Also, `const operator[]` did not do an `access_at`, which I fixed.
Reviewed By: mbouaziz
Differential Revision: D5320427
fbshipit-source-id: c31c5ea
Summary: Unknown library returns the unknown pointer as well as the top interval.
Reviewed By: mbouaziz, jvillard
Differential Revision: D5282669
fbshipit-source-id: 34c7e18
Summary:
This diff tries to achieve the followings: if we have the following C++ codes:
```
bool foo(int x, int y) {
return &x == &y;
}
```
We want the C++ frontend to emit Sil as if the input is written as
```
bool foo(int x, int y) {
if (&x == &y) return 1; else return 0;
}
```
This matches the behavior of our Java frontend.
The reason why we prefer an explicit branch is that it will force the backend to eagerly produce two different specs for `foo`. Without the explicit branch, for the above example the backend would produce one spec with `return = (&x == &y)` as the post condition, which is not ideal because (1) we don't want local variables to escape to the function summary, and (2) with the knowledge that no two local variables may alias each other, the backend could actually determines that `&x == &y` is always false, emitting a more precise postcondition `return = 0`. This is not possible if we do not eagerly resolve the comparison expression.
Reviewed By: akotulski
Differential Revision: D5260745
fbshipit-source-id: 6bbbf99
Summary:
:
There are throw wrapper functions like `std::__throw_bad_alloc()` defined in both libstdc++ (https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/include/bits/functexcept.h) and libc++ (e.g. 907c1196a7/include/new (L145)). Folly actually exports some of them as well (diffusion/FBS/browse/master/fbcode/folly/portability/BitsFunctexcept.h). The function body of those wrappers merely throws the corresponding exception. My understanding is that the primary purpose of the wrappers is to throw the exception if everything goes well and to fall back to something reasonable when exception is disabled (e.g. when `-fno-exceptions` is passed to the compiler).
The problem is that infer doesn't really understand what those functions do, and I've seen some false positives get reported as a result of it. So to remove those FPs we need to either model them or handle them specially. Modeling those wrappers by either whitelisting them or overriding the include files turns out to be difficult, as those wrappers are only declared but not defined in the STL headers. Their implementations are not available to Infer so whitelisting them does nothing, and if I provide custom implementations in the headers then normal compilation process will be disrupted because the linker would complain about duplicated implementation.
What I did here is to replace functions whose name matches one of the throw wrapper's name with a `BuiltinDecls.exit`. I have to admit that this is a bit hacky: initially I was trying to do something more general: replacing functions with `noreturn` attribute with `BuitinDecls.exit`. That did not work because, CMIIW, the current frontend only exports function attributes for functions with actual bodies, not declaration-only functions. I'd love to be informed if there are better ways to handle those wrappers.
Reviewed By: jeremydubreil
Differential Revision: D5266030
fbshipit-source-id: 4580227
Summary:
Read/write race errors should always show one trace for a read and one trace for a write.
We forget to pass the conflicting writes to the reporting function in one case, which prevented us from showing a well-formed trace.
Fixed it by making the `conflicts` parameter non-optional
Reviewed By: jberdine
Differential Revision: D5209332
fbshipit-source-id: 05da01a
Summary:
For now, we just support clearing the taint on a return value.
Ideally, we would associate a kind with the sanitizer and only clear taint that matches that kind.
However, it's fairly complicated to make that work properly with footprint sources.
I have some ideas about how to do it with passthroughs instead, but let's just do the simple thing for now.
Reviewed By: jeremydubreil
Differential Revision: D5141906
fbshipit-source-id: a5b8b5e
Dino Distefano
Mehdi Bouaziz
Sungkeun Cho
Sam Blackshear
Daiva Naudziuniene
Jeremy Dubreil
Jules Villard
Radu Grigore
Dulma Churchill
Josh Berdine
Kyriakos Nikolaos Gkorogiannis
Jia Chen
Andrzej Kotulski
Martino Luca
Kihong Heo