Summary:
Before this change, analyses using HIL needed to pass `IdAcessPathMapDomain.empty` to abstract interpreter, and would get back the map as part of the post.
This is a confusing API and was a pain point for Dino in trying to use HIL.
This diff adds a HIL wrapper around the abstract interpreter that hides these details.
It replaces `LowerHIL.makeDefault` as the new "simplest possible way" to use HIL.
Reviewed By: jberdine
Differential Revision: D6125597
fbshipit-source-id: 560856b
Summary:
Install ocamlformat from github as part of `make devsetup`, and use it
for formatting OCaml (and jbuild) code.
Reviewed By: jvillard
Differential Revision: D6092464
fbshipit-source-id: 4ba0845
Summary:
Expanding traces currently works in the following way:
Given a `TraceElem.Kind` `k` we want to report in `foo`, we look for a callee `C` of `foo` that has a `TraceElem.Kind` equal to `k` in its summary, grab the summary for `C`, then repeat until we bottom out.
This isn't very flexible: it insists on equality between `TraceElem.Kind`'s as the criteria for expanding a trace.
This diff introduces a new `matches` function for deciding when to expand a trace from a caller into a callee.
Clients that don't want strict equality can implement a fuzzier kind of equality inside this function.
I've gone ahead and done this for the trace elemes of thread-safety.
In the near future, equivalent access paths won't always compare equal from caller to callee, so we want to match their suffixes instead.
Reviewed By: jvillard
Differential Revision: D5914118
fbshipit-source-id: 233c603
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:
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:
Record the list of access paths (if any) used in the index expression for each array access.
This will make it possible to use array accesses as sinks in Quandary
Reviewed By: jeremydubreil
Differential Revision: D5531356
fbshipit-source-id: 8204909
Summary:
It's nice to have "raw" as the default kind of access path, since it's used much more often than the abstraction.
This is also a prereq for supporting index expressions in access paths, since we'll need mutual recursion between accesses and access paths.
Reviewed By: jeremydubreil
Differential Revision: D5529807
fbshipit-source-id: cb3f521
Summary: This gives us more expressive power when defining sources--we can use heuristics like "`foo(o)` only returns a source when `o` is not a constant".
Reviewed By: jvillard
Differential Revision: D5467935
fbshipit-source-id: f3d581d
Summary: Long lists will be broken into lines rather than stretch out on a single line.
Reviewed By: jvillard
Differential Revision: D5424323
fbshipit-source-id: 115f16a
Summary:
Conversion and reformat of infer source using ocamlformat
auto-formatting tool.
Current status:
- Because Reason does not handle docstrings, the output of the
conversion is not 'Warning 50'-clean, meaning that there are
docstrings with ambiguous placement. I'll need to manually fix
them just before landing.
Reviewed By: jvillard
Differential Revision: D5225546
fbshipit-source-id: 3bd2786
Summary:
First step toward addressing bad traces that happen in examples like
```
void sourceMethod() {
Obj source = (Obj) InferTaint.inferSecretSource();
callSameSink(null, source); // index: 1
}
void callSameSink(Obj o1, Obj o2) {
callMySink1(o1); // flows via o1 ~= index 0, don't expand
callMySink2(o2); // flows via o2 ~= index 1, can expand
}
void callMySink1(Obj o) {
... // maybe interesting something happens here that doesn't happen in callMySink2
InferTaint.inferSensitiveSink(o); // flows via o ~= index 0, can expand
}
void callMySink2(Obj o) {
InferTaint.inferSensitiveSink(o); // flows via o ~= index 0, can expand
}
```
The issue is that when we recreate a trace to the sink starting from `sourceMethod`, we don't know which of the calls to `callMySink` to expand/include in the trace.
If we expand the call to `callMySink(o1)`, we'll get a bogus trace.
In this example that's not such a big deal, but imagine the case where the first call to `callMySink` is a different function that transitively calls the sink through some long and confusing path.
Remembering the index at which taint flows into each sink will let us choose which sinks are safe to expand.
This diff just adds indexes to the API; it's not actually propagating the index info or using it during expansion yet.
Reviewed By: jeremydubreil
Differential Revision: D5170563
fbshipit-source-id: ba4b096
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: Have found this useful in Quandary for fbcode, where we want to do this for folly due to its use of assembly (details in comments).
Reviewed By: mbouaziz
Differential Revision: D5167564
fbshipit-source-id: bf6d7e0
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: 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: Stops Quandary errors from getting dropped on the floor when it runs alongside the other checkers.
Reviewed By: jeremydubreil
Differential Revision: D5010801
fbshipit-source-id: 2847f61
Summary:
Last step for converting thread-safety and quandary to HIL.
Push the logic for managing the id map and converting the instructions into a functor.
This way, client analyses can simply write HIL transfer functions and call the functor.
Reviewed By: jberdine
Differential Revision: D4989987
fbshipit-source-id: 485169e
Summary:
This is step further simplify the code to avoid cases where the summary of the procedure being analyzed can exist in two different versions:
# one version is the summary passed as parameter to every checker
# the other is a copy of the summary in the in-memory specs table
This diff implements:
# the analysis always run through the `Ondemand` module (was already the case before)
# the summary of the procedure being analyzed is created at the beginning of the on-demand analysis call
# all the checkers run in sequence, update their respective part of the payload and log errors to the error table
# the summary is store at the end of the on-demand analysis call
Reviewed By: sblackshear
Differential Revision: D4787414
fbshipit-source-id: 2d115c9
Summary: Fail early when there is no registered callbacks to run the analysis of a procedure on-demand
Reviewed By: sblackshear
Differential Revision: D4573726
fbshipit-source-id: a8ee74b
Summary:
At one point I thought we'd want to have lots of different schedulers for things like exploring loops in different orders, but that hasn't materialized.
Let's make the common use-case simpler by hiding the `Scheduler` parameter inside the `AbstractInterpreter` module.
We can always expose `MakeWithScheduler` later if we want to.
Reviewed By: jberdine
Differential Revision: D4508095
fbshipit-source-id: 726e051
Summary:
When the receiver type and return type of an unknown call are the same, propagate taint to both the receiver and the return type.
This does the right thing for common "builder-style" methods that both update and return the receiver.
We already had custom models for a few such methods (e.g., `StringBuilder.append`), but we can remove them now.
Reviewed By: jeremydubreil
Differential Revision: D4490071
fbshipit-source-id: 325ea88
Summary: This will be useful in upcoming changes to the thread-safety analysis as well.
Reviewed By: dkgi
Differential Revision: D4402146
fbshipit-source-id: c750127
Summary:
A domain should not definite its initial state, since distinct users of the domain may want to choose different initial values.
For example, one user might want to bind all of the formals to some special values, and one user might want the initial domain to be an empty map
This diff makes this distinction clear in the types by (a) requiring the initial state to be passed to the abstract interpreter and (b) lifting the requirement that abstract domains define `initial`.
Reviewed By: jberdine
Differential Revision: D4359629
fbshipit-source-id: cbcee28
Summary:
There's a lot of boilerplate work to be done when adding a new kind of source.
This diff tries to reduce the boilerplate by making a functor do all the work.
The functor:
(1) adds a notion of "footprint kind" to the source
(2) packages the source with a call site
Reviewed By: jvillard
Differential Revision: D4349224
fbshipit-source-id: 5e1701a
Summary:
We currently can only model the return values of functions as sources.
In order to model inputs of endpoints as sources, we need the capability to treat the formals of certain functions as sources too.
This diff adds that capability by adding a function for getting the tainted sources to the source module, then using that info in the analysis.
Reviewed By: jeremydubreil
Differential Revision: D4314738
fbshipit-source-id: dd7d423
Summary:
Previously, summaries worked by flattening the access tree representing the post of the procedure into (in essence) a list of functions from caller input traces to callee output traces.
This is inefficient in many ways, and is also much more complex than just using the original access tree as the summary.
One big inefficiency of the old way is this: calling `Trace.append` is slow, and we want to do it as few times as possible.
Under the old summary system, we would do it at most once for each "function" in the summary list.
Now, we'll do it at most once for each node in the access tree summary.
This will be a smaller number of calls, since each node can summarize many input/output relationships.
Reviewed By: jeremydubreil
Differential Revision: D4271579
fbshipit-source-id: 34e407a
Summary:
Utils contains definitions intended to be in the global namespace for
all of the infer code-base, as well as pretty-printing functions, and
assorted utility functions mostly for dealing with files and processes.
This diff changes the module opened into the global namespace to
IStd (Std conflict with extlib), and moves the pretty-printing
definitions from Utils to Pp.
Reviewed By: jvillard
Differential Revision: D4232457
fbshipit-source-id: 1e070e0
Summary:
In Java, we handle unknown code by propagating behavior from the parameters of the unknown function call to the return value (or constructed object, in the case of a constructor). But we do this in a somewhat silly way--generating a new summary with these semantics at each unknown call site. Instead, this diff introduces these two options as predefined behaviors and adds specialized code for them.
As a side effect of this approach, unknown functions are no longer counted as passthroughs. This is ok; the original behavior was less of a reasoned decision and more of an unintended consequence of the way we decided to handle unknown code.
This new approach ought to be more efficient than the old one, and as a virtuous side effect it will be easier to specify how to handle unknown code in other languages like C++.
Reviewed By: jeremydubreil
Differential Revision: D4205624
fbshipit-source-id: bf97445
Summary:
There's not really a concept of callee here, so s/callee/callsite/, and "to"
suggests we get the callee whereas we update it, so s/to/with/.
Feel free to bikeshed further.
Reviewed By: sblackshear
Differential Revision: D4153426
fbshipit-source-id: 6ea762c
Summary: A must-have for reporting taint errors and any other interprocedural error where the trace is sufficiently complex.
Reviewed By: jvillard
Differential Revision: D4124072
fbshipit-source-id: 26b3b2b
Summary: A must-have for reporting taint errors and any other interprocedural error where the trace is sufficiently complex.
Reviewed By: jvillard
Differential Revision: D4106352
fbshipit-source-id: b2677e6
Summary:
Right now, taint gets lost if it flows into a constructor or procedure whose implementation is missing.
Since the core Java (e.g., String) and Android classes (e.g, Intent) are among these, this is bad.
We could handle this by writing a bunch of models instead, but that would be a lot of work (plus we may still miss cases).
Reviewed By: jvillard
Differential Revision: D4051591
fbshipit-source-id: 65851c8