1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223

//! Report information about function calls.

use super::utils::GroupByIterator;
use super::utils::{BuildResolver, DefPathResolver};
use crate::write_csv;
use corpus_database::tables::Loader;
use corpus_queries_derive::datapond_query;
use log::info;
use std::collections::{HashMap, HashSet};
use std::convert::TryInto;
use std::path::Path;

/// Count how many functions are called from each unsafe block.
fn count_called_functions(loader: &Loader) {
    let unsafe_block_calls;
    datapond_query! {
        load loader {
            relations(unsafe_terminators, terminators_call),
        }
        output unsafe_block_calls(
            build: Build, block: BasicBlock, unsafe_scope: Scope,
            check_mode: BlockCheckMode, call: FunctionCall,
            unsafety: Unsafety, abi: Abi, return_ty: Type)
        unsafe_block_calls(
            build, block, unsafe_scope, check_mode, call, unsafety, abi, return_ty
        ) :-
            unsafe_terminators(
                .build=build, .block=block, .unsafe_scope=unsafe_scope,
                .check_mode=check_mode),
            terminators_call(
                .block=block, .call=call, .unsafety=unsafety,
                .abi=abi, .return_ty=return_ty).
    }
    let unsafe_block_calls_relation = unsafe_block_calls.elements;
    info!(
        "Number of calls in unsafe blocks: {}",
        unsafe_block_calls_relation.len()
    );

    let unsafe_block_call_counts_relation: Vec<_> = unsafe_block_calls_relation
        .iter()
        .safe_group_by(
            |&&(build, _block, unsafe_scope, check_mode, _call, _unsafety, _abi, _return_ty)| {
                (build, unsafe_scope, check_mode)
            },
        )
        .into_iter()
        .map(|((build, unsafe_scope, check_mode), group)| {
            (
                build,
                unsafe_scope,
                check_mode,
                group.count().try_into().unwrap(),
            )
        })
        .collect();
    info!(
        "Number of unsafe blocks with calls: {}",
        unsafe_block_call_counts_relation.len()
    );

    let blocks_with_calls: HashSet<_> = unsafe_block_call_counts_relation
        .iter()
        .map(|&(_build, unsafe_scope, _check_mode, _call_count)| unsafe_scope)
        .collect();

    let unsafe_block_no_calls_relation: Vec<_> = loader
        .load_unsafe_blocks()
        .iter()
        .filter(
            |(_build, _mir_body_def_path, scope, _expansion_kind, _check_mode, _span)| {
                !blocks_with_calls.contains(scope)
            },
        )
        .cloned()
        .collect();
    info!(
        "Number of unsafe blocks with non-const calls: {}",
        unsafe_block_no_calls_relation.len()
    );

    loader.store_unsafe_block_calls(unsafe_block_calls_relation);
    loader.store_unsafe_block_call_counts(unsafe_block_call_counts_relation);
    loader.store_unsafe_block_no_calls(unsafe_block_no_calls_relation);
}

/// Report how many function calls each unsafe block contains.
fn report_called_functions(loader: &Loader, report_path: &Path) {
    let def_path_resolver = DefPathResolver::new(loader);
    let build_resolver = BuildResolver::new(loader);
    let strings = loader.load_strings();
    let abis = loader.load_abis();

    let unsafe_block_calls = loader.load_unsafe_block_calls();
    let unsafe_block_calls = unsafe_block_calls.iter().map(
        |&(build, block, unsafe_scope, check_mode, call, unsafety, abi, _return_ty)| {
            (
                build,
                build_resolver.resolve(build),
                block,
                unsafe_scope,
                check_mode.to_string(),
                call,
                unsafety.to_string(),
                strings[abis[abi]].to_string(),
            )
        },
    );
    write_csv!(report_path, unsafe_block_calls);
    info!("reported unsafe_block_calls");

    let unsafe_block_call_counts = loader.load_unsafe_block_call_counts();
    let unsafe_block_call_counts =
        unsafe_block_call_counts
            .iter()
            .map(|&(build, unsafe_scope, check_mode, call_count)| {
                (
                    build,
                    build_resolver.resolve(build),
                    unsafe_scope,
                    check_mode.to_string(),
                    call_count,
                )
            });
    write_csv!(report_path, unsafe_block_call_counts);
    info!("reported unsafe_block_call_counts");

    let unsafe_block_no_calls = loader.load_unsafe_block_no_calls();
    let unsafe_block_no_calls = unsafe_block_no_calls.iter().map(
        |&(build, mir_body_def_path, scope, expansion_kind, check_mode, _span)| {
            (
                build,
                build_resolver.resolve(build),
                def_path_resolver.resolve(mir_body_def_path),
                scope,
                expansion_kind.to_string(),
                check_mode.to_string(),
            )
        },
    );
    write_csv!(report_path, unsafe_block_no_calls);
    info!("reported unsafe_block_no_calls");
}

/// Find all calls in unsafe functions that call non-constant targets. In other
/// words, find all calls that call function pointers.
fn report_non_const_call_targets(loader: &Loader, report_path: &Path) {
    let const_calls: HashSet<_> = loader
        .load_terminators_call_const_target()
        .iter()
        .map(|(call, _def_path)| *call)
        .collect();
    let build_resolver = BuildResolver::new(loader);
    let strings = loader.load_strings();
    let abis = loader.load_abis();
    let unsafe_block_calls = loader.load_unsafe_block_calls();
    let non_const_calls = unsafe_block_calls.iter().flat_map(
        |(build, block, unsafe_scope, check_mode, call, unsafety, abi, _return_ty)| {
            if const_calls.contains(call) {
                None
            } else {
                Some((
                    build,
                    build_resolver.resolve(*build),
                    block,
                    unsafe_scope,
                    check_mode.to_string(),
                    call,
                    unsafety.to_string(),
                    strings[abis[*abi]].to_string(),
                ))
            }
        },
    );
    write_csv!(report_path, non_const_calls);
    info!("reported non_const_call_targets");
}

/// Find all calls in unsafe functions that call constant targets. The call
/// targets that appear as constants:
///
/// 1. Static function calls.
/// 2. Static method calls.
/// 3. Dynamic calls on trait objects.
/// 4. Calls of closures.
fn report_const_call_targets(loader: &Loader, report_path: &Path) {
    let const_calls_map: HashMap<_, _> = loader
        .load_terminators_call_const_target()
        .iter()
        .cloned()
        .collect();
    let def_path_resolver = DefPathResolver::new(loader);
    let build_resolver = BuildResolver::new(loader);
    let strings = loader.load_strings();
    let abis = loader.load_abis();
    let unsafe_block_calls = loader.load_unsafe_block_calls();
    let const_calls = unsafe_block_calls.iter().flat_map(
        |(build, block, unsafe_scope, check_mode, call, unsafety, abi, _return_ty)| {
            const_calls_map.get(call).map(|def_path| {
                Some((
                    build,
                    build_resolver.resolve(*build),
                    def_path_resolver.resolve(*def_path),
                    block,
                    unsafe_scope,
                    check_mode.to_string(),
                    call,
                    unsafety.to_string(),
                    strings[abis[*abi]].to_string(),
                ))
            })
        },
    );
    write_csv!(report_path, const_calls);
    info!("reported const_call_targets");
}

pub fn query(loader: &Loader, report_path: &Path) {
    count_called_functions(loader);
    report_called_functions(loader, report_path);
    report_non_const_call_targets(loader, report_path);
    report_const_call_targets(loader, report_path);
}