xref: /freebsd/contrib/llvm-project/lldb/source/Commands/CommandObjectMemoryTag.cpp (revision 5f757f3ff9144b609b3c433dfd370cc6bdc191ad)
1 //===-- CommandObjectMemoryTag.cpp ----------------------------------------===//
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 "CommandObjectMemoryTag.h"
10 #include "lldb/Host/OptionParser.h"
11 #include "lldb/Interpreter/CommandOptionArgumentTable.h"
12 #include "lldb/Interpreter/CommandReturnObject.h"
13 #include "lldb/Interpreter/OptionArgParser.h"
14 #include "lldb/Interpreter/OptionGroupFormat.h"
15 #include "lldb/Interpreter/OptionValueString.h"
16 #include "lldb/Target/ABI.h"
17 #include "lldb/Target/Process.h"
18 
19 using namespace lldb;
20 using namespace lldb_private;
21 
22 #define LLDB_OPTIONS_memory_tag_read
23 #include "CommandOptions.inc"
24 
25 class CommandObjectMemoryTagRead : public CommandObjectParsed {
26 public:
27   CommandObjectMemoryTagRead(CommandInterpreter &interpreter)
28       : CommandObjectParsed(interpreter, "tag",
29                             "Read memory tags for the given range of memory."
30                             " Mismatched tags will be marked.",
31                             nullptr,
32                             eCommandRequiresTarget | eCommandRequiresProcess |
33                                 eCommandProcessMustBePaused) {
34     // Address
35     m_arguments.push_back(
36         CommandArgumentEntry{CommandArgumentData(eArgTypeAddressOrExpression)});
37     // Optional end address
38     m_arguments.push_back(CommandArgumentEntry{
39         CommandArgumentData(eArgTypeAddressOrExpression, eArgRepeatOptional)});
40   }
41 
42   ~CommandObjectMemoryTagRead() override = default;
43 
44 protected:
45   void DoExecute(Args &command, CommandReturnObject &result) override {
46     if ((command.GetArgumentCount() < 1) || (command.GetArgumentCount() > 2)) {
47       result.AppendError(
48           "wrong number of arguments; expected at least <address-expression>, "
49           "at most <address-expression> <end-address-expression>");
50       return;
51     }
52 
53     Status error;
54     addr_t start_addr = OptionArgParser::ToRawAddress(
55         &m_exe_ctx, command[0].ref(), LLDB_INVALID_ADDRESS, &error);
56     if (start_addr == LLDB_INVALID_ADDRESS) {
57       result.AppendErrorWithFormatv("Invalid address expression, {0}",
58                                     error.AsCString());
59       return;
60     }
61 
62     // Default 1 byte beyond start, rounds up to at most 1 granule later
63     addr_t end_addr = start_addr + 1;
64 
65     if (command.GetArgumentCount() > 1) {
66       end_addr = OptionArgParser::ToRawAddress(&m_exe_ctx, command[1].ref(),
67                                                LLDB_INVALID_ADDRESS, &error);
68       if (end_addr == LLDB_INVALID_ADDRESS) {
69         result.AppendErrorWithFormatv("Invalid end address expression, {0}",
70                                       error.AsCString());
71         return;
72       }
73     }
74 
75     Process *process = m_exe_ctx.GetProcessPtr();
76     llvm::Expected<const MemoryTagManager *> tag_manager_or_err =
77         process->GetMemoryTagManager();
78 
79     if (!tag_manager_or_err) {
80       result.SetError(Status(tag_manager_or_err.takeError()));
81       return;
82     }
83 
84     const MemoryTagManager *tag_manager = *tag_manager_or_err;
85 
86     MemoryRegionInfos memory_regions;
87     // If this fails the list of regions is cleared, so we don't need to read
88     // the return status here.
89     process->GetMemoryRegions(memory_regions);
90 
91     lldb::addr_t logical_tag = tag_manager->GetLogicalTag(start_addr);
92 
93     // The tag manager only removes tag bits. These addresses may include other
94     // non-address bits that must also be ignored.
95     ABISP abi = process->GetABI();
96     if (abi) {
97       start_addr = abi->FixDataAddress(start_addr);
98       end_addr = abi->FixDataAddress(end_addr);
99     }
100 
101     llvm::Expected<MemoryTagManager::TagRange> tagged_range =
102         tag_manager->MakeTaggedRange(start_addr, end_addr, memory_regions);
103 
104     if (!tagged_range) {
105       result.SetError(Status(tagged_range.takeError()));
106       return;
107     }
108 
109     llvm::Expected<std::vector<lldb::addr_t>> tags = process->ReadMemoryTags(
110         tagged_range->GetRangeBase(), tagged_range->GetByteSize());
111 
112     if (!tags) {
113       result.SetError(Status(tags.takeError()));
114       return;
115     }
116 
117     result.AppendMessageWithFormatv("Logical tag: {0:x}", logical_tag);
118     result.AppendMessage("Allocation tags:");
119 
120     addr_t addr = tagged_range->GetRangeBase();
121     for (auto tag : *tags) {
122       addr_t next_addr = addr + tag_manager->GetGranuleSize();
123       // Showing tagged adresses here until we have non address bit handling
124       result.AppendMessageWithFormatv("[{0:x}, {1:x}): {2:x}{3}", addr,
125                                       next_addr, tag,
126                                       logical_tag == tag ? "" : " (mismatch)");
127       addr = next_addr;
128     }
129 
130     result.SetStatus(eReturnStatusSuccessFinishResult);
131   }
132 };
133 
134 #define LLDB_OPTIONS_memory_tag_write
135 #include "CommandOptions.inc"
136 
137 class CommandObjectMemoryTagWrite : public CommandObjectParsed {
138 public:
139   class OptionGroupTagWrite : public OptionGroup {
140   public:
141     OptionGroupTagWrite() = default;
142 
143     ~OptionGroupTagWrite() override = default;
144 
145     llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
146       return llvm::ArrayRef(g_memory_tag_write_options);
147     }
148 
149     Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_value,
150                           ExecutionContext *execution_context) override {
151       Status status;
152       const int short_option =
153           g_memory_tag_write_options[option_idx].short_option;
154 
155       switch (short_option) {
156       case 'e':
157         m_end_addr = OptionArgParser::ToRawAddress(
158             execution_context, option_value, LLDB_INVALID_ADDRESS, &status);
159         break;
160       default:
161         llvm_unreachable("Unimplemented option");
162       }
163 
164       return status;
165     }
166 
167     void OptionParsingStarting(ExecutionContext *execution_context) override {
168       m_end_addr = LLDB_INVALID_ADDRESS;
169     }
170 
171     lldb::addr_t m_end_addr = LLDB_INVALID_ADDRESS;
172   };
173 
174   CommandObjectMemoryTagWrite(CommandInterpreter &interpreter)
175       : CommandObjectParsed(interpreter, "tag",
176                             "Write memory tags starting from the granule that "
177                             "contains the given address.",
178                             nullptr,
179                             eCommandRequiresTarget | eCommandRequiresProcess |
180                                 eCommandProcessMustBePaused) {
181     // Address
182     m_arguments.push_back(
183         CommandArgumentEntry{CommandArgumentData(eArgTypeAddressOrExpression)});
184     // One or more tag values
185     m_arguments.push_back(CommandArgumentEntry{
186         CommandArgumentData(eArgTypeValue, eArgRepeatPlus)});
187 
188     m_option_group.Append(&m_tag_write_options);
189     m_option_group.Finalize();
190   }
191 
192   ~CommandObjectMemoryTagWrite() override = default;
193 
194   Options *GetOptions() override { return &m_option_group; }
195 
196 protected:
197   void DoExecute(Args &command, CommandReturnObject &result) override {
198     if (command.GetArgumentCount() < 2) {
199       result.AppendError("wrong number of arguments; expected "
200                          "<address-expression> <tag> [<tag> [...]]");
201       return;
202     }
203 
204     Status error;
205     addr_t start_addr = OptionArgParser::ToRawAddress(
206         &m_exe_ctx, command[0].ref(), LLDB_INVALID_ADDRESS, &error);
207     if (start_addr == LLDB_INVALID_ADDRESS) {
208       result.AppendErrorWithFormatv("Invalid address expression, {0}",
209                                     error.AsCString());
210       return;
211     }
212 
213     command.Shift(); // shift off start address
214 
215     std::vector<lldb::addr_t> tags;
216     for (auto &entry : command) {
217       lldb::addr_t tag_value;
218       // getAsInteger returns true on failure
219       if (entry.ref().getAsInteger(0, tag_value)) {
220         result.AppendErrorWithFormat(
221             "'%s' is not a valid unsigned decimal string value.\n",
222             entry.c_str());
223         return;
224       }
225       tags.push_back(tag_value);
226     }
227 
228     Process *process = m_exe_ctx.GetProcessPtr();
229     llvm::Expected<const MemoryTagManager *> tag_manager_or_err =
230         process->GetMemoryTagManager();
231 
232     if (!tag_manager_or_err) {
233       result.SetError(Status(tag_manager_or_err.takeError()));
234       return;
235     }
236 
237     const MemoryTagManager *tag_manager = *tag_manager_or_err;
238 
239     MemoryRegionInfos memory_regions;
240     // If this fails the list of regions is cleared, so we don't need to read
241     // the return status here.
242     process->GetMemoryRegions(memory_regions);
243 
244     // The tag manager only removes tag bits. These addresses may include other
245     // non-address bits that must also be ignored.
246     ABISP abi = process->GetABI();
247     if (abi)
248       start_addr = abi->FixDataAddress(start_addr);
249 
250     // We have to assume start_addr is not granule aligned.
251     // So if we simply made a range:
252     // (start_addr, start_addr + (N * granule_size))
253     // We would end up with a range that isn't N granules but N+1
254     // granules. To avoid this we'll align the start first using the method that
255     // doesn't check memory attributes. (if the final range is untagged we'll
256     // handle that error later)
257     lldb::addr_t aligned_start_addr =
258         tag_manager->ExpandToGranule(MemoryTagManager::TagRange(start_addr, 1))
259             .GetRangeBase();
260 
261     lldb::addr_t end_addr = 0;
262     // When you have an end address you want to align the range like tag read
263     // does. Meaning, align the start down (which we've done) and align the end
264     // up.
265     if (m_tag_write_options.m_end_addr != LLDB_INVALID_ADDRESS)
266       end_addr = m_tag_write_options.m_end_addr;
267     else
268       // Without an end address assume number of tags matches number of granules
269       // to write to
270       end_addr =
271           aligned_start_addr + (tags.size() * tag_manager->GetGranuleSize());
272 
273     // Remove non-address bits that aren't memory tags
274     if (abi)
275       end_addr = abi->FixDataAddress(end_addr);
276 
277     // Now we've aligned the start address so if we ask for another range
278     // using the number of tags N, we'll get back a range that is also N
279     // granules in size.
280     llvm::Expected<MemoryTagManager::TagRange> tagged_range =
281         tag_manager->MakeTaggedRange(aligned_start_addr, end_addr,
282                                      memory_regions);
283 
284     if (!tagged_range) {
285       result.SetError(Status(tagged_range.takeError()));
286       return;
287     }
288 
289     Status status = process->WriteMemoryTags(tagged_range->GetRangeBase(),
290                                              tagged_range->GetByteSize(), tags);
291 
292     if (status.Fail()) {
293       result.SetError(status);
294       return;
295     }
296 
297     result.SetStatus(eReturnStatusSuccessFinishResult);
298   }
299 
300   OptionGroupOptions m_option_group;
301   OptionGroupTagWrite m_tag_write_options;
302 };
303 
304 CommandObjectMemoryTag::CommandObjectMemoryTag(CommandInterpreter &interpreter)
305     : CommandObjectMultiword(
306           interpreter, "tag", "Commands for manipulating memory tags",
307           "memory tag <sub-command> [<sub-command-options>]") {
308   CommandObjectSP read_command_object(
309       new CommandObjectMemoryTagRead(interpreter));
310   read_command_object->SetCommandName("memory tag read");
311   LoadSubCommand("read", read_command_object);
312 
313   CommandObjectSP write_command_object(
314       new CommandObjectMemoryTagWrite(interpreter));
315   write_command_object->SetCommandName("memory tag write");
316   LoadSubCommand("write", write_command_object);
317 }
318 
319 CommandObjectMemoryTag::~CommandObjectMemoryTag() = default;
320