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 void NORETURN reportSoftRSSLimit(uptr RssLimitMb) {
40   ScopedErrorReport Report;
41   Report.append("Soft RSS limit of %zu MB exhausted, current RSS is %zu MB\n",
42                 RssLimitMb, GetRSS() >> 20);
43 }
44 
45 void NORETURN reportHardRSSLimit(uptr RssLimitMb) {
46   ScopedErrorReport Report;
47   Report.append("Hard RSS limit of %zu MB exhausted, current RSS is %zu MB\n",
48                 RssLimitMb, GetRSS() >> 20);
49 }
50 
51 // This could potentially be called recursively if a CHECK fails in the reports.
52 void NORETURN reportCheckFailed(const char *File, int Line,
53                                 const char *Condition, u64 Value1, u64 Value2) {
54   static atomic_u32 NumberOfCalls;
55   if (atomic_fetch_add(&NumberOfCalls, 1, memory_order_relaxed) > 2) {
56     // TODO(kostyak): maybe sleep here?
57     trap();
58   }
59   ScopedErrorReport Report;
60   Report.append("CHECK failed @ %s:%d %s ((u64)op1=%llu, (u64)op2=%llu)\n",
61                 File, Line, Condition, Value1, Value2);
62 }
63 
64 // Generic string fatal error message.
65 void NORETURN reportError(const char *Message) {
66   ScopedErrorReport Report;
67   Report.append("%s\n", Message);
68 }
69 
70 void NORETURN reportInvalidFlag(const char *FlagType, const char *Value) {
71   ScopedErrorReport Report;
72   Report.append("invalid value for %s option: '%s'\n", FlagType, Value);
73 }
74 
75 // The checksum of a chunk header is invalid. This could be caused by an
76 // {over,under}write of the header, a pointer that is not an actual chunk.
77 void NORETURN reportHeaderCorruption(void *Ptr) {
78   ScopedErrorReport Report;
79   Report.append("corrupted chunk header at address %p\n", Ptr);
80 }
81 
82 // Two threads have attempted to modify a chunk header at the same time. This is
83 // symptomatic of a race-condition in the application code, or general lack of
84 // proper locking.
85 void NORETURN reportHeaderRace(void *Ptr) {
86   ScopedErrorReport Report;
87   Report.append("race on chunk header at address %p\n", Ptr);
88 }
89 
90 // The allocator was compiled with parameters that conflict with field size
91 // requirements.
92 void NORETURN reportSanityCheckError(const char *Field) {
93   ScopedErrorReport Report;
94   Report.append("maximum possible %s doesn't fit in header\n", Field);
95 }
96 
97 // We enforce a maximum alignment, to keep fields smaller and generally prevent
98 // integer overflows, or unexpected corner cases.
99 void NORETURN reportAlignmentTooBig(uptr Alignment, uptr MaxAlignment) {
100   ScopedErrorReport Report;
101   Report.append("invalid allocation alignment: %zu exceeds maximum supported "
102                 "alignment of %zu\n",
103                 Alignment, MaxAlignment);
104 }
105 
106 // See above, we also enforce a maximum size.
107 void NORETURN reportAllocationSizeTooBig(uptr UserSize, uptr TotalSize,
108                                          uptr MaxSize) {
109   ScopedErrorReport Report;
110   Report.append("requested allocation size %zu (%zu after adjustments) exceeds "
111                 "maximum supported size of %zu\n",
112                 UserSize, TotalSize, MaxSize);
113 }
114 
115 void NORETURN reportOutOfMemory(uptr RequestedSize) {
116   ScopedErrorReport Report;
117   Report.append("out of memory trying to allocate %zu bytes\n", RequestedSize);
118 }
119 
120 static const char *stringifyAction(AllocatorAction Action) {
121   switch (Action) {
122   case AllocatorAction::Recycling:
123     return "recycling";
124   case AllocatorAction::Deallocating:
125     return "deallocating";
126   case AllocatorAction::Reallocating:
127     return "reallocating";
128   case AllocatorAction::Sizing:
129     return "sizing";
130   }
131   return "<invalid action>";
132 }
133 
134 // The chunk is not in a state congruent with the operation we want to perform.
135 // This is usually the case with a double-free, a realloc of a freed pointer.
136 void NORETURN reportInvalidChunkState(AllocatorAction Action, void *Ptr) {
137   ScopedErrorReport Report;
138   Report.append("invalid chunk state when %s address %p\n",
139                 stringifyAction(Action), Ptr);
140 }
141 
142 void NORETURN reportMisalignedPointer(AllocatorAction Action, void *Ptr) {
143   ScopedErrorReport Report;
144   Report.append("misaligned pointer when %s address %p\n",
145                 stringifyAction(Action), Ptr);
146 }
147 
148 // The deallocation function used is at odds with the one used to allocate the
149 // chunk (eg: new[]/delete or malloc/delete, and so on).
150 void NORETURN reportDeallocTypeMismatch(AllocatorAction Action, void *Ptr,
151                                         u8 TypeA, u8 TypeB) {
152   ScopedErrorReport Report;
153   Report.append("allocation type mismatch when %s address %p (%d vs %d)\n",
154                 stringifyAction(Action), Ptr, TypeA, TypeB);
155 }
156 
157 // The size specified to the delete operator does not match the one that was
158 // passed to new when allocating the chunk.
159 void NORETURN reportDeleteSizeMismatch(void *Ptr, uptr Size,
160                                        uptr ExpectedSize) {
161   ScopedErrorReport Report;
162   Report.append(
163       "invalid sized delete when deallocating address %p (%zu vs %zu)\n", Ptr,
164       Size, ExpectedSize);
165 }
166 
167 void NORETURN reportAlignmentNotPowerOfTwo(uptr Alignment) {
168   ScopedErrorReport Report;
169   Report.append(
170       "invalid allocation alignment: %zu, alignment must be a power of two\n",
171       Alignment);
172 }
173 
174 void NORETURN reportCallocOverflow(uptr Count, uptr Size) {
175   ScopedErrorReport Report;
176   Report.append("calloc parameters overflow: count * size (%zu * %zu) cannot "
177                 "be represented with type size_t\n",
178                 Count, Size);
179 }
180 
181 void NORETURN reportInvalidPosixMemalignAlignment(uptr Alignment) {
182   ScopedErrorReport Report;
183   Report.append(
184       "invalid alignment requested in posix_memalign: %zu, alignment must be a "
185       "power of two and a multiple of sizeof(void *) == %zu\n",
186       Alignment, sizeof(void *));
187 }
188 
189 void NORETURN reportPvallocOverflow(uptr Size) {
190   ScopedErrorReport Report;
191   Report.append("pvalloc parameters overflow: size %zu rounded up to system "
192                 "page size %zu cannot be represented in type size_t\n",
193                 Size, getPageSizeCached());
194 }
195 
196 void NORETURN reportInvalidAlignedAllocAlignment(uptr Alignment, uptr Size) {
197   ScopedErrorReport Report;
198   Report.append("invalid alignment requested in aligned_alloc: %zu, alignment "
199                 "must be a power of two and the requested size %zu must be a "
200                 "multiple of alignment\n",
201                 Alignment, Size);
202 }
203 
204 } // namespace scudo
205