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
Summary:
This is a minimal change to (poorly) recognize and model std::mutex
lock and unlock methods, and to surface all thread safety issues for
C++ based on the computed summaries with no filtering.
This ignores much of the Java analysis, including everything about the
Threads domain. The S/N is comically low at this point.
Reviewed By: sblackshear
Differential Revision: D5120485
fbshipit-source-id: 0f08caa
Summary: Gflags is a popular library used to create command line arguments. Flags shouldn't flow directly to `exec` etc.
Reviewed By: jvillard, mbouaziz
Differential Revision: D5058393
fbshipit-source-id: ab062f8
Summary: String are very important for taint analysis, have to make sure that we have the right models/the right behaviors for unknown code.
Reviewed By: jvillard
Differential Revision: D5054832
fbshipit-source-id: 7e7ee07
Summary:
This commit fixes a problem that the buffer overrun checker incorrectly
stops when a global variable (bottom) is involved in control flow.
In the new version, abstract memories return Top for unanalyzed abstract
variables.
Reviewed By: mbouaziz
Differential Revision: D5016447
fbshipit-source-id: 5132448
Summary:
The code was pretty fragile, it's less fragile now. We should probably just
delete that and start outputting proper class/package info directly in the
report.json instead of reverse-engineering them.
Fixes#640
Reviewed By: jeremydubreil
Differential Revision: D4905973
fbshipit-source-id: 1590067
Summary:
An array has a static or dynamic length (number of elements), but it also has a
stride, determined by the type of the element: `sizeof(element_type)`. We don't
have a good `sizeof()` function available on SIL types, so record that stride
in the array type.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D4969697
fbshipit-source-id: 98e0670
Summary: In particular, the heuristics for propagating taint via unknown code needs to be aware of the frontend's trick of introducing dummy return variables.
Reviewed By: mbouaziz
Differential Revision: D5046345
fbshipit-source-id: da87665
Summary:
HIL had only been tested in Java, and it made some assumptions about what array expressions look like (the LHS is always resolvable to an access path) and assignments (the LHS is always an access path) that aren't true in C.
Fixed the code so we won't crash in this case.
Thanks to jeremydubreil for catching this.
Reviewed By: jeremydubreil
Differential Revision: D5047649
fbshipit-source-id: e8484f4
Summary:
There are two pointer-related operations you can do in C++ but not Java that we need to support in taint analysis:
(1) `*formal_ptr = ...` when `formal_ptr` is a formal that's a pointer type. Java doesn't have raw pointers, so we didn't need to handle this case.
(2) Passing by reference, which Java also doesn't have (everything is pass-by-value).
Reviewed By: mbouaziz
Differential Revision: D5041246
fbshipit-source-id: 4e8f962
Summary: Same as D5026082, but allowing specification in JSON rather than harcoded in Infer.
Reviewed By: jeremydubreil
Differential Revision: D5030042
fbshipit-source-id: 8a6cfee
Summary: A lot of C++ library functions look like this, so it's important to have.
Reviewed By: mbouaziz
Differential Revision: D5026082
fbshipit-source-id: 6f421b6
Summary: Making sure simple passthroughs like the identity function work in C++.
Reviewed By: mbouaziz
Differential Revision: D5024031
fbshipit-source-id: ce48ead
Summary:
Needed because this is how the Clang frontend translates returns of non-POD, non pointer values (I think)?
Will handle the more general case of pass by reference soon.
Reviewed By: jvillard
Differential Revision: D5017653
fbshipit-source-id: 1fbcea5
Summary:
`[a, b] < [a, _]` and `[_, a] < [b, a]` are most probably false (it comes from size < size)
Mark definitely unsatisfied conditions as B1, others as B2+
Reviewed By: KihongHeo, jvillard
Differential Revision: D4962107
fbshipit-source-id: ba8f469
Summary:
The bufferoverrun checkers can now be run with:
infer -a checkers --bufferoverrun -- ...
Reviewed By: jeremydubreil
Differential Revision: D5010689
fbshipit-source-id: 2eaa396
Summary:
The Siof checkers can now be run with:
infer -a checkers --siof -- ...
and also runs by default using:
infer -a checkers -- ...
Reviewed By: jberdine
Differential Revision: D5009731
fbshipit-source-id: e0e2168
Summary:
Don't store redundant information in C++ template Type.Name.t.
New signature:
```
| CppClass (qual_name, template_args)
```
For example, for `std::shared_ptr<int>`, will look like this:
```
| CppClass (["std", "shared_ptr"], Template [int])
```
While it used to be:
```
| CppClass (["std", "shared_ptr<int>"], Template (["std", "shared_ptr"], [int]))
```
Reviewed By: jberdine, mbouaziz
Differential Revision: D4834512
fbshipit-source-id: cb1c570
Summary:
Title.
The way types are printed is completely valid, but little weird for some C++ programmers:
`int const` - same as `const int`
`int * const` - pointer is `const`, value under it is not
`int const *` - pointer is not `const`, but the value is
`int const * const` - both pointer and value are const
Reviewed By: jberdine
Differential Revision: D4962180
fbshipit-source-id: dcb02e3
Summary:
- Use Logging for logging
- Add a few extra debug (not ON by default)
- No space before colon
Depends on D4961957
Reviewed By: KihongHeo
Differential Revision: D4961989
fbshipit-source-id: 7c8697d
Summary:
As an interprocedural checker, SIOF should not run unless explicitly required.
Make it a new type of analyzer like other similar checkers.
Reviewed By: mbouaziz
Differential Revision: D4937820
fbshipit-source-id: a9e2d38
Summary: `bufferoverrun` is not part of `checkers` yet so bufferoverrun tests require their own Makefile
Reviewed By: jvillard
Differential Revision: D4937558
fbshipit-source-id: 20380f1
Summary: The flakiness is exercised by upgrading the OCaml compiler to 4.04.0.
Reviewed By: jberdine
Differential Revision: D4859904
fbshipit-source-id: 0dd7ff6
Summary:
Make it possible to write one model which will be used by all template instantiations.
There is one big missing piece: infer never tries to do template instantiation by itself. With current code, it's possible to use generic models
as long as header contains `__infer_generic_model` annotation (see the test as an example).
This is not viable to modify all headers with this annotation hence infer will try to do template instantiation for generic models in later diffs.
Reviewed By: jberdine
Differential Revision: D4826365
fbshipit-source-id: 2233e42
Summary: `__attribute__((annotate("")))` is better way of passing information to the frontend
Reviewed By: jberdine
Differential Revision: D4818805
fbshipit-source-id: 6e8add2
Summary:
Adds a new type and branching for a missing path of execution.
closes#575
Reviewed By: jvillard
Differential Revision: D4738681
fbshipit-source-id: f72344c
Summary:
This issue was spotted in the wild. There may be more of those, unfortunately it's hard to predict
More general problem is that types in infer frontend diverge from clang's types for DerivedToBase cast.
Then, infer uses types from clang anyway and that confuses backend. Getting it always right is very hard
Reviewed By: jvillard
Differential Revision: D4754081
fbshipit-source-id: 5fb7069
Summary:
All tests were redirecting `stderr` into duplicates.txt which made it much harder to see other error messages in stderr (such as uncaught exceptions).
To mitigate it, write duplicates to separate file and don't redirect `stderr` to another file.
Reviewed By: jvillard
Differential Revision: D4728938
fbshipit-source-id: 8ad2fc8
Summary:
We were including hex of empty string if mangled name was not empty (so for all C++ functions).
Instead, include hex of a source file only if it's not empty
Reviewed By: mbouaziz
Differential Revision: D4705388
fbshipit-source-id: 55b6587
Summary:
Procnames files are now reversed qualifier lists with `#` as separator (instead of `::` which needs to be escaped in bash).
Because of the mechanism that is used to obtain qualifiers, it also affects naming for ObjC classes.
Examples:
```
std::unique_ptr<int>::get -> get#unique_ptr<int>#std#__MANGLED,...__ // C++ method
folly::split -> split#folly#__MANGLED,..._ // function within namespace
NSNumber numberWithBool: -> numberWithBool:#NSNumber#class // ObjC method
```
Reviewed By: jvillard
Differential Revision: D4689701
fbshipit-source-id: c3acfc6
Summary:
Updated version of the plugin exports some missing `VarDecls`. To make sure it doesn't break again,
add a test that didn't work before.
Reviewed By: dulmarod
Differential Revision: D4674123
fbshipit-source-id: 0c1677a
Summary:
Enrich the domain of SIOF to contain, as well as the globals needed by a
procedure, the globals that the procedure initializes. Also add the possibility
to model some procedures as initializing some variables. Use that mechanism to
teach the checker about `std::ios_base::Init`.
Reviewed By: mbouaziz
Differential Revision: D4588284
fbshipit-source-id: d72fc87
Summary:
This gives a way for users to flag safe methods regarding SIOF, for instance if
the problematic paths in the method cannot happen before `main()` has started.
Reviewed By: akotulski
Differential Revision: D4578700
fbshipit-source-id: 6542dcf
Summary:
Infer used to report null dereference when field was accessed later:
```
vector<int> v;
int& a = v[0]; // should be EMPTY_VECTOR_ACCESS here, but it wasn't reported
int b = a; // was NULL_DEREFERENCE here
```
To avoid this problem, model all accesses to vector as dereference of its internal `beginPtr` field.
Reviewed By: jberdine
Differential Revision: D4481942
fbshipit-source-id: 2142894
Summary:
This modifies `CTrans_utils.dereference_value_from_result` function. Reasons:
1. Type in Sil.Load tuple is supposed to be the type of Ident.t field (result), not Exp.t (source)
2. Inside `dereference_value_from_result` we used wrong type when `~strip_pointer:true` - it used original type instead of the resulting one
3. Fixing (2), uncovered similar issue in `CTrans_utils.cast_operation` - it should have used resulting type, not original one
Changed tests are expected:
1. `deprecated_hack.cpp` test was how I discovered this issue (it was very wrong)
2. the other test also had issues, now it's correct
Sadly, there was no logic I followed when writing this change - I stuffed changes in a way that fits, but it may be breaking something somewhere else.
Reviewed By: jberdine
Differential Revision: D4481895
fbshipit-source-id: b139c59
Summary: Access to std::vector shouldn't be treated as SKIP. Implementation is simple enough to use one from std:: headers
Reviewed By: jvillard
Differential Revision: D4339577
fbshipit-source-id: d1fbbee
Summary:
Change the domain of SIOF to be based on sets of pvar * location instead of
single pvars. This allows us to group several accesses together. However, we
still get different trace elems for different instructions in a proc. We do two
things to get around this limitation and get a trace where all accesses within
the same proc are grouped together, instead of one trace for each access:
1. A post-processing phase at the end of the analysis of one proc collects all
the globals directly accessed in the proc into a single trace elem.
2. When creating the error trace, unpack this set into several trace elements
to see each access (at its correct location) separately in the trace.
This is a bit hacky and another way would be to extend the API of traces to
handle in-procedure accesses natively instead of shoe-horning them. However
since SIOF is the only one to use this, it introduces less boilerplate to do it
that way for now.
Also, a few .mlis for good measure.
Reviewed By: sblackshear
Differential Revision: D4299070
fbshipit-source-id: 3bbb5c2
Summary: These direct tests were still mostly relying on PHONY targets.
Reviewed By: jberdine
Differential Revision: D4326469
fbshipit-source-id: 37b2d0a
Summary: Our C++ model magic didn't work when instantiating smart pointers with volatile types. Fix it
Reviewed By: jvillard
Differential Revision: D4313271
fbshipit-source-id: 55ffb98
Summary: Globals that are constexpr-initializable do not participate in SIOF.
Reviewed By: sblackshear
Differential Revision: D4277216
fbshipit-source-id: fd601c8
Summary:
Remember which globals are static locals.
It's useful to distinguish those from global variables in objc and in the SIOF
checker. Previously in ObjC we would accomplish that by looking at the name of
the variable, but that wouldn't work reliably in C++. Keep the old method around for
now as the way we deal with static locals in ObjC needs some fixing.
Reviewed By: akotulski
Differential Revision: D4198993
fbshipit-source-id: 357dd11
Summary:
Currently cfg nodes are written into dot files in whatever order they
appear in a hash table. This seems unnecessarily sensitive, so this
diff sorts the nodes.
Reviewed By: dulmarod
Differential Revision: D4232377
fbshipit-source-id: a907cc6
Daiva Naudziuniene
Sam Blackshear
Jeremy Dubreil
Jia Chen
Jules Villard
Andrzej Kotulski
Mehdi Bouaziz
Martino Luca
Sungkeun Cho
Josh Berdine
Kihong Heo
Dulma Churchill
Paco Estevez Garcia