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: We get the wrong answer on most of them for now, but that is expected
Reviewed By: ngorogiannis
Differential Revision: D5429242
fbshipit-source-id: 4899079
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:
This just makes the warnings silent for now. We may improve the analysis to check if the null check on the captured fields are consistent with the annotation on the corresponding parameters.
Eradicate also has the same issue. I added a test to outline this. The biabduction analysis will also probably fail on the same of annotation lookup. We may want implement the proper fix at the level of `Annotation.field_has_annot`.
Reviewed By: sblackshear
Differential Revision: D5419243
fbshipit-source-id: 6460de8
Summary:
First steps towards implementing diff analysis functionalities inside infer
itself. What works: run infer, checkout parent, re-run infer, checkout top
revision, compute the reportdiff (but no final surfacing on the console). Lots
of TODO still, inlined in the code.
Reviewed By: jberdine
Differential Revision: D5364226
fbshipit-source-id: 5b7f9a5
Summary: CFG nodes were not connected and some instructions ended up in wrong place. Fix those issues
Reviewed By: dulmarod
Differential Revision: D5406720
fbshipit-source-id: 2a70e1a
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:
Add support for converting without actually converting. To be used as
a landing pad for rebasing over the conversion.
Reviewed By: jvillard
Differential Revision: D5379967
fbshipit-source-id: 1bd932d
Summary: Adding to the Quandary tests, the list of tests that are already working for the bi-abduction based taint analysis.
Reviewed By: sblackshear
Differential Revision: D5395734
fbshipit-source-id: c4f2e79
Summary:
Fixes#683
Disclaimer: I don't know what XML namespaces/namespace prefixes are, but this seems to do the trick.
Reviewed By: mbouaziz
Differential Revision: D5381480
fbshipit-source-id: 3da16e7
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: So that it get rebuilt. Test is clang_compilation_db_relpath
Reviewed By: mbouaziz
Differential Revision: D5364561
fbshipit-source-id: 8cae984
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 was passing the argument multiple times rather than once with all the accepted values
Reviewed By: jvillard
Differential Revision: D5338509
fbshipit-source-id: 22b86a5
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:
Once the fixed/preexisting/introduced sets have been computed, they endure
further filtering which may decide that more of them are equal. These bugs just
get dropped on the floor. Put these into preexisting as well instead, at least
in the case of the "skip_duplicated_types_on_filenames" filter.
Reviewed By: martinoluca
Differential Revision: D5274248
fbshipit-source-id: 99b3f3d
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:
:
What is relevant for the Buck integration is not the list of bugs that we find in a single target, which is essentially identical to testing `infer -- javac ...`, but to make sure that we still find the issues that are involving several Buck targets, and later other things like the caching mechanism.
This should also make the tests faster.
Reviewed By: jberdine, jvillard
Differential Revision: D5250205
fbshipit-source-id: 7f66b68
Summary: This change introduces the a new argument that lets you restrict the results of a differential report to only certain files.
Reviewed By: mbouaziz
Differential Revision: D5236626
fbshipit-source-id: 52711e9
Summary: We had a model for `Pools.SimplePool`, but were missing models for `Pools.Pool`. Since `SimplePool` and `SynchronizedPool` both extend `Pool`, modeling it should cover all of the cases.
Reviewed By: ngorogiannis
Differential Revision: D5236280
fbshipit-source-id: 9bbdb25
Summary:
:
No longer use deprecated reporting function for the suggest nullable checker
Depends on D5205009
Reviewed By: grievejia
Differential Revision: D5205843
fbshipit-source-id: f6dd059
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:
This messes up with the Buck cache: if infer recaptures a file with only trivial changes that shouldn't affect the capture Buck will still believe it has to reanalyze everything that depends on that file if there's non-deterministic data in infer's output.
Re-use the `--buck` flag used by the Java Buck integration for mostly the same purposes. Add a few special cases for the flavours integration (eg: keep capture data).
Change perf stats registration to take `Config.buck_cache_mode` into account instead of relying on each call site to handle that peculiarity correctly. Also, there's no need to create the perf stats directories before calling the registration function since it will do that too.
Reviewed By: jeremydubreil
Differential Revision: D5192311
fbshipit-source-id: 334ea6e
Summary: This also allows us to better test that the new commands will keep working.
Reviewed By: jeremydubreil
Differential Revision: D5172891
fbshipit-source-id: 169bd6f
Summary: We were almost always using `~report_reachable:true`, and in the cases where we weren't it is fine to do so. In general, a sink could read any state from its parameters, so it makes sense to complain if anything reachable from them is tainted.
Reviewed By: mbouaziz
Differential Revision: D5169067
fbshipit-source-id: ea7d659
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:
- model `exit` as `Bottom`
- model `fgetc` as returning `[-1; 255]` rather than `[-1; +oo]`
- reduced the number of model functions for simple models
Reviewed By: KihongHeo
Differential Revision: D5137485
fbshipit-source-id: 943eeeb
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:
This diff fixes unintentional bottoms in pointer arithmetic of inferbo.
The pointer arithmetic on addresses of variables (not array) just returns
the operand.
Reviewed By: jvillard
Differential Revision: D5060424
fbshipit-source-id: 495d8b8
Summary: Using Conjunction for thread join has known false negatives. Finer grained recording of threading information fixes this.
Reviewed By: sblackshear
Differential Revision: D5111161
fbshipit-source-id: aab483c
Summary: This fixes a couple of false positives as objects of BufferedReader don't need to be closed if the wrapped reader resource gets closed correctly.
Reviewed By: sblackshear
Differential Revision: D5106596
fbshipit-source-id: 725fb80
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: Useful to have Eradicate and Biabduction agree on how to inform that the analysis that some objects are not null.
Reviewed By: sblackshear
Differential Revision: D5075127
fbshipit-source-id: 9e56981
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:
Previously all knowledge of the dynamic length of such arrays was lost to infer:
```
void foo(int len) {
int a[len];
}
```
The translation of this program would make no reference to `len` (except as a
param of `foo`).
Translate this "initialization" using the existing `__set_array_length` infer
builtin, as:
```
# Declare local a[_]
n$0 = len;
__set_array_length(a, len);
```
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D4969446
fbshipit-source-id: dff860f
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:
Introduce `infer-<command>` for each command, except for internal commands
(only `infer-clang` for now) which are not exported. Install these executables
(which are just symlinks to `infer`) on `make install`. The main executable
looks at the name it was invoked with to figure out if it should behave as a
particular command.
Get rid of `InferClang`, `InferAnalyze`, and `InferPrint`. As a bonus, we now
only need to build one executable: `infer`, which should be a few seconds
faster (less link time).
`InferAnalyze` is now `infer-analyze` and `InferPrint` is `infer-print`. To run
`InferClang`, use a symlink named `clang`, `clang++`, etc. to `infer`. There
are such symlinks available in "infer/lib/wrappers/" already.
I also noticed that the scripts in xcodebuild_wrappers/ don't seem useful
anymore, so use wrappers/ instead, as for `make`.
Reviewed By: mbouaziz
Differential Revision: D5036495
fbshipit-source-id: 4a90030
Summary: Same as D5026082, but allowing specification in JSON rather than harcoded in Infer.
Reviewed By: jeremydubreil
Differential Revision: D5030042
fbshipit-source-id: 8a6cfee
Sam Blackshear
Mehdi Bouaziz
Jia Chen
Sungkeun Cho
Dulma Churchill
Jeremy Dubreil
Jules Villard
Andrzej Kotulski
azhdar
Josh Berdine
Kihong Heo
Martino Luca
Daiva Naudziuniene
Dino Distefano
Kyriakos Nikolaos Gkorogiannis
Don Stewart
Peter O'Hearn