1 //===-- report.cpp ----------------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "report.h"
10 
11 #include "atomic_helpers.h"
12 #include "string_utils.h"
13 
14 #include <stdarg.h>
15 
16 namespace scudo {
17 
18 class ScopedErrorReport {
19 public:
20   ScopedErrorReport() : Message() { Message.append("Scudo ERROR: "); }
21   void append(const char *Format, ...) {
22     va_list Args;
23     va_start(Args, Format);
24     Message.append(Format, Args);
25     va_end(Args);
26   }
27   NORETURN ~ScopedErrorReport() {
28     outputRaw(Message.data());
29     setAbortMessage(Message.data());
30     die();
31   }
32 
33 private:
34   ScopedString Message;
35 };
36 
37 inline void NORETURN trap() { __builtin_trap(); }
38 
39 // This could potentially be called recursively if a CHECK fails in the reports.
40 void NORETURN reportCheckFailed(const char *File, int Line,
41                                 const char *Condition, u64 Value1, u64 Value2) {
42   static atomic_u32 NumberOfCalls;
43   if (atomic_fetch_add(&NumberOfCalls, 1, memory_order_relaxed) > 2) {
44     // TODO(kostyak): maybe sleep here?
45     trap();
46   }
47   ScopedErrorReport Report;
48   Report.append("CHECK failed @ %s:%d %s ((u64)op1=%llu, (u64)op2=%llu)\n",
49                 File, Line, Condition, Value1, Value2);
50 }
51 
52 // Generic string fatal error message.
53 void NORETURN reportError(const char *Message) {
54   ScopedErrorReport Report;
55   Report.append("%s\n", Message);
56 }
57 
58 void NORETURN reportInvalidFlag(const char *FlagType, const char *Value) {
59   ScopedErrorReport Report;
60   Report.append("invalid value for %s option: '%s'\n", FlagType, Value);
61 }
62 
63 // The checksum of a chunk header is invalid. This could be caused by an
64 // {over,under}write of the header, a pointer that is not an actual chunk.
65 void NORETURN reportHeaderCorruption(void *Ptr) {
66   ScopedErrorReport Report;
67   Report.append("corrupted chunk header at address %p\n", Ptr);
68 }
69 
70 // Two threads have attempted to modify a chunk header at the same time. This is
71 // symptomatic of a race-condition in the application code, or general lack of
72 // proper locking.
73 void NORETURN reportHeaderRace(void *Ptr) {
74   ScopedErrorReport Report;
75   Report.append("race on chunk header at address %p\n", Ptr);
76 }
77 
78 // The allocator was compiled with parameters that conflict with field size
79 // requirements.
80 void NORETURN reportSanityCheckError(const char *Field) {
81   ScopedErrorReport Report;
82   Report.append("maximum possible %s doesn't fit in header\n", Field);
83 }
84 
85 // We enforce a maximum alignment, to keep fields smaller and generally prevent
86 // integer overflows, or unexpected corner cases.
87 void NORETURN reportAlignmentTooBig(uptr Alignment, uptr MaxAlignment) {
88   ScopedErrorReport Report;
89   Report.append("invalid allocation alignment: %zu exceeds maximum supported "
90                 "alignment of %zu\n",
91                 Alignment, MaxAlignment);
92 }
93 
94 // See above, we also enforce a maximum size.
95 void NORETURN reportAllocationSizeTooBig(uptr UserSize, uptr TotalSize,
96                                          uptr MaxSize) {
97   ScopedErrorReport Report;
98   Report.append("requested allocation size %zu (%zu after adjustments) exceeds "
99                 "maximum supported size of %zu\n",
100                 UserSize, TotalSize, MaxSize);
101 }
102 
103 void NORETURN reportOutOfMemory(uptr RequestedSize) {
104   ScopedErrorReport Report;
105   Report.append("out of memory trying to allocate %zu bytes\n", RequestedSize);
106 }
107 
108 static const char *stringifyAction(AllocatorAction Action) {
109   switch (Action) {
110   case AllocatorAction::Recycling:
111     return "recycling";
112   case AllocatorAction::Deallocating:
113     return "deallocating";
114   case AllocatorAction::Reallocating:
115     return "reallocating";
116   case AllocatorAction::Sizing:
117     return "sizing";
118   }
119   return "<invalid action>";
120 }
121 
122 // The chunk is not in a state congruent with the operation we want to perform.
123 // This is usually the case with a double-free, a realloc of a freed pointer.
124 void NORETURN reportInvalidChunkState(AllocatorAction Action, void *Ptr) {
125   ScopedErrorReport Report;
126   Report.append("invalid chunk state when %s address %p\n",
127                 stringifyAction(Action), Ptr);
128 }
129 
130 void NORETURN reportMisalignedPointer(AllocatorAction Action, void *Ptr) {
131   ScopedErrorReport Report;
132   Report.append("misaligned pointer when %s address %p\n",
133                 stringifyAction(Action), Ptr);
134 }
135 
136 // The deallocation function used is at odds with the one used to allocate the
137 // chunk (eg: new[]/delete or malloc/delete, and so on).
138 void NORETURN reportDeallocTypeMismatch(AllocatorAction Action, void *Ptr,
139                                         u8 TypeA, u8 TypeB) {
140   ScopedErrorReport Report;
141   Report.append("allocation type mismatch when %s address %p (%d vs %d)\n",
142                 stringifyAction(Action), Ptr, TypeA, TypeB);
143 }
144 
145 // The size specified to the delete operator does not match the one that was
146 // passed to new when allocating the chunk.
147 void NORETURN reportDeleteSizeMismatch(void *Ptr, uptr Size,
148                                        uptr ExpectedSize) {
149   ScopedErrorReport Report;
150   Report.append(
151       "invalid sized delete when deallocating address %p (%zu vs %zu)\n", Ptr,
152       Size, ExpectedSize);
153 }
154 
155 void NORETURN reportAlignmentNotPowerOfTwo(uptr Alignment) {
156   ScopedErrorReport Report;
157   Report.append(
158       "invalid allocation alignment: %zu, alignment must be a power of two\n",
159       Alignment);
160 }
161 
162 void NORETURN reportCallocOverflow(uptr Count, uptr Size) {
163   ScopedErrorReport Report;
164   Report.append("calloc parameters overflow: count * size (%zu * %zu) cannot "
165                 "be represented with type size_t\n",
166                 Count, Size);
167 }
168 
169 void NORETURN reportInvalidPosixMemalignAlignment(uptr Alignment) {
170   ScopedErrorReport Report;
171   Report.append(
172       "invalid alignment requested in posix_memalign: %zu, alignment must be a "
173       "power of two and a multiple of sizeof(void *) == %zu\n",
174       Alignment, sizeof(void *));
175 }
176 
177 void NORETURN reportPvallocOverflow(uptr Size) {
178   ScopedErrorReport Report;
179   Report.append("pvalloc parameters overflow: size %zu rounded up to system "
180                 "page size %zu cannot be represented in type size_t\n",
181                 Size, getPageSizeCached());
182 }
183 
184 void NORETURN reportInvalidAlignedAllocAlignment(uptr Alignment, uptr Size) {
185   ScopedErrorReport Report;
186   Report.append("invalid alignment requested in aligned_alloc: %zu, alignment "
187                 "must be a power of two and the requested size %zu must be a "
188                 "multiple of alignment\n",
189                 Alignment, Size);
190 }
191 
192 } // namespace scudo
193