Summary: Type is not enough to say a function call of `Provider.get` is expensive or not.
Reviewed By: jvillard
Differential Revision: D20366206
fbshipit-source-id: 83d3e8741
Summary:
This diff uses a type parameter of `Provider.get` to decide whether assigning expensive cost to the
function call or not. For example, if the type is small one like `Provider<Integer>`, it be
evaluated to have a unit cost, otherwise a linear cost.
To get the return type of `Provider.get`, I added a simple analyzer that collects "casted" types
backwards. In Sil, while the function call statement loses the return type, e.g,
```
n$5=_fun_Object Provider.get()(n$3:javax.inject.Provider*);
```
the `n$5`'s value is usually casted to a specific type at some point later.
```
*&$irvar0:java.lang.Object*=n$5
n$8=*&$irvar0:java.lang.Object*
n$9=_fun___cast(n$8:java.lang.Object*,sizeof(t=java.lang.Integer;sub_t=( sub )(cast)):void)
```
So, the analyzer starts from the cast statements backward, collecting the types to cast for each
variables.
Reviewed By: ezgicicek
Differential Revision: D20345268
fbshipit-source-id: 704b42ec1
Summary:
A java byte is not a short and a java character is not a C character. Fix those types by mapping them to what the spec ordains.
An extra advantage is that this establishes a bijection between java types and their project in the `sil` type system, so pretty printing in Java mode can actually be made to work.
Reviewed By: mityal
Differential Revision: D20330525
fbshipit-source-id: 00ac2294b
Summary:
Invariant map of Inferbo, a map from node to abstract memory, is used in other checkers. In order to
avoid duplicated Inferbo analyses, it caches calculated invariant maps independently to summary
DB. The reason is that Inferbo's summary contains one abstract memory of the exit node, rather than
a map from all nodes to abstract memories.
This diff changes it to keep only one invariant map at a time. Since registered checkers are
applied to the same function one by one, usually the singleton cache should be enough to avoid the
duplicated Inferbo running. (I can think of a corner case when multiple checkers depend on
Inferbo's results and Inferbo's modeled functions are different to that of them, but it should work
in most of the cases.)
Reviewed By: jvillard
Differential Revision: D20248172
fbshipit-source-id: db86655d0
Summary:
The issue type `ZERO_EXECUTION_TIME` actually corresponds to bottom state but has been mistakenly used to mean
- unreachable nodes (program never reaching exit state)
- having zero cost (e.g. for allocations).
Note that, for execution costs, the latter doesn't make sense since we always incur a unit cost for the start node. Hence, a function with empty body will have unit cost. For allocations or IO however, we only incur costs for specific primitives, so a function with no allocations/IO could have a zero cost. However, there is no point reporting functions with zero cost as a specific issue type. Instead, what we want to track is the former, i.e. functions whose cost becomes 0 due to program never reaching exit state.
This diff aims to split these cases into two by only reporting on the latter and adds traces to bottom/unreachable cost by creating a special category in polynomials.
Next diff will rename `ZERO_XXX` to `XXX_UNREACHABLE_AT_EXIT`.
Reviewed By: skcho
Differential Revision: D20005774
fbshipit-source-id: 46b9abd5a
Summary:
Current domain of Inferbo cannot handle float values. This diff evaluates float constants to the top
interval.
Reviewed By: ezgicicek
Differential Revision: D20116361
fbshipit-source-id: e6e398bbd
Summary: The semantics of the `values` function of Java enum class was missing, when it is called outside the class initializer. This diff gets the size of the enum elements from the summary of class initializer function, `<clinit>`.
Reviewed By: ezgicicek
Differential Revision: D20094880
fbshipit-source-id: 7362bba1c
Summary:
This ignores the error memory status (e.g. when condition expression is evaluated to bottom), in
order to keep analyze following code.
```
if ( e ) // e is evaluated to bottom due to a problem of Inferbo {
... // code here was not analyzed before
}
```
Reviewed By: ezgicicek
Differential Revision: D20067434
fbshipit-source-id: a1713722c
Summary: This diff suppresses integer overflow issues in functions that includes "hash" in its name.
Reviewed By: jvillard
Differential Revision: D19942654
fbshipit-source-id: d86fa4f00
Summary:
In Inferbo, the bottom memory is introduced when a node is unreachable by pruning, i.e.
`[[e]] <= [0,0]` on `prune(e)`. This diff distinguishes whether `[[e]]` is `[0,0]` (unreachable)
or bottom (it could not evaluate `e` by some unknown reasons).
Reviewed By: ezgicicek
Differential Revision: D19902046
fbshipit-source-id: 7706017d6
Summary:
Core v13 APIs stopped raising `Not_found` and instead raise
`Not_found_s`, which wreaks havoc in our codebase. Carefully inspect
each `Not_found` and add `Not_found_s` where needed (that way it's
compatible with both Core v12 and v13 for now).
Reviewed By: jberdine
Differential Revision: D19861585
fbshipit-source-id: 9a5361ae9
Summary:
The big one:
- stop using polymorphic `<>`, `<`, `>`, ..
- add `<>` to `PolyVariantEqual` escape hatch now that `<>` is as taboo as `=`
- Interestingly, there were a lot of uses of `Z.(x < y)`, which although
they seem to use `Z.lt` actually used polymorphic comparison. The actual
comparison infix operators of `Z` are cleverly hidden in `Z.Compare`
instead, which makes them impractical to use...
Reviewed By: jberdine
Differential Revision: D19861584
fbshipit-source-id: 5dce08ad9
Summary:
Polymorphic compare is bad, 'mkay? I also tried changing this to do what
the comment says the function does (keep the first term instead of the
"largest" term) but that resulted in test changes so I kept the original
behaviour instead.
Reviewed By: jberdine
Differential Revision: D19861587
fbshipit-source-id: d57fd4a02
Summary:
When finding a proper constructor for `std::make_shared`, the given parameter types are sometimes
slightly different, e.g., const int vs int. This diff loosens the condition of the types on finding
constructors.
Reviewed By: ngorogiannis
Differential Revision: D19743198
fbshipit-source-id: f90213109
Summary: This diff makes the taint analysis in Inferbo inter-procedural: adding symbolic taint values and substitute them at function call statements.
Reviewed By: ezgicicek
Differential Revision: D19411022
fbshipit-source-id: 4ff9a590a
Summary:
This diff introduces two issue types: `BUFFER_OVERRUN_T1` and `INFERBO_ALLOC_IS_TAINTED`, which
denotes tainted values are used in array accesses and memory allocations, respectively.
Note that the taint analysis is intra-procedural for now.
Reviewed By: ezgicicek
Differential Revision: D19410536
fbshipit-source-id: af85148ec
Summary:
This diff adds a taint domain in Inferbo. The taint value will be used to find vulnerable array
accesses in the following diffs.
Reviewed By: ezgicicek
Differential Revision: D19391028
fbshipit-source-id: 566b4c0fe
Summary: This diff returns non-symbolic value (top) for unknown external function calls because the symbolic values sometimes make it hard to understand costs.
Reviewed By: ezgicicek
Differential Revision: D18685715
fbshipit-source-id: 1b39c718b
Summary:
`String` and `StringBuilder` both implement `CharSequence`. Let's generalize the model for `String` to `CharSequence` wherever possible and add missing models for
- `StringBuilder.append`
- `StringBuilder.toString`
Reviewed By: skcho
Differential Revision: D19558009
fbshipit-source-id: 0dfdb21af
Summary:
Java's String models were broken for
- initializing a String object with a locally defined constant string (which is an `Object*` in SIL).
- initializing a String object with a `char`/`byte` array
This diff fixes them and also adds models for `new String ()`.
Reviewed By: skcho
Differential Revision: D19662180
fbshipit-source-id: 23968d0aa
Summary:
`replace_make_shared` is finding a constructor by iterating all fields of type structs, which may be
expensive if there are lots of fields or `replace_make_shared` is called many times with the same parameters.
Reviewed By: ngorogiannis
Differential Revision: D19446260
fbshipit-source-id: c5c279ca5
Summary: This diff fixes the array access checking function for nested global arrays. We had assumed that RHS of `store` statement in SIL does not include array access expression, but that is not true: for global arrays, SIL can have statements like `*LHS = GlobalArray[n][m]`.
Reviewed By: ezgicicek
Differential Revision: D19300153
fbshipit-source-id: 256325642
Summary:
This diff gives semantics of `std::make_shared` as simple constructor, i.e., it changes function
call of `std::make_chared<C>(i)` to the constructor `C(i)`.
Reviewed By: ngorogiannis
Differential Revision: D19432338
fbshipit-source-id: 0d838e555
Summary: `String.split(regexp)` returns an array that is split by the given regexp. If the regexp doesn't match, the original string is returned. Hence, the resulting array's length must be in `[1, max(1, n_u -1)]` where`n_u` is the upper bound of the string's length.
Reviewed By: dulmarod
Differential Revision: D19578318
fbshipit-source-id: 675af7376
Summary:
This diff gets global constant array values from their initializers. The `find_global_array` function is
added to memory domain, which finds values of global array locations during the ondemand value
generation.
Reviewed By: ngorogiannis
Differential Revision: D19300143
fbshipit-source-id: 7b0b84c42
Summary:
Inferbo analyzed some program points unreachable incorrectly, because of unsound semantics of band
operator, which did not handle the case when given parameters are pointer values.
Reviewed By: ngorogiannis
Differential Revision: D19392705
fbshipit-source-id: dd590508c
Summary:
This diff revises the generation of unknown value. If the type of the unknown value generating is
int, it does not add the "Unknown" pointer/array value.
Reviewed By: ngorogiannis
Differential Revision: D19392696
fbshipit-source-id: e1b3c9a3a
Summary:
This diffs does: (1) move `get_formals` to `BufferOverrunUtils` (2) use separate `get_formals` in
`BufferOverrunChecker`, in order to simplify the following diff.
Reviewed By: jvillard
Differential Revision: D19432280
fbshipit-source-id: bfb4df118
Summary:
This diff avoids that `array_sizeof` returns bottom value when given Java enum values, which
introduced unreachable code inadvertently.
Reviewed By: ngorogiannis
Differential Revision: D19409077
fbshipit-source-id: 2816fd995
Summary: The type-name definition for Java can be potentially improved (eg increase sharing, or comparison speed, much like `QualifiedCppName`) by switching away from `Mangled.t` which is essentially a string. First step is to abstract the type.
Reviewed By: jberdine
Differential Revision: D19087508
fbshipit-source-id: 91a81f63b
Sungkeun Cho
Nikos Gorogiannis
Ezgi Çiçek
Jules Villard