1 // Copyright 2016 The Fuchsia Authors
2 // Copyright (c) 2008-2012 Travis Geiselbrecht
3 //
4 // Use of this source code is governed by a MIT-style
5 // license that can be found in the LICENSE file or at
6 // https://opensource.org/licenses/MIT
7 
8 #include <arch.h>
9 #include <arch/ops.h>
10 #include <ctype.h>
11 #include <debug.h>
12 #include <kernel/cmdline.h>
13 #include <kernel/thread.h>
14 #include <list.h>
15 #include <platform.h>
16 #include <platform/debug.h>
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <string.h>
20 #include <vm/pmm.h>
21 #include <zircon/time.h>
22 #include <zircon/types.h>
23 
24 #include <lib/console.h>
25 
26 
27 static int cmd_display_mem(int argc, const cmd_args *argv, uint32_t flags);
28 static int cmd_modify_mem(int argc, const cmd_args *argv, uint32_t flags);
29 static int cmd_fill_mem(int argc, const cmd_args *argv, uint32_t flags);
30 static int cmd_reset(int argc, const cmd_args *argv, uint32_t flags);
31 static int cmd_memtest(int argc, const cmd_args *argv, uint32_t flags);
32 static int cmd_copy_mem(int argc, const cmd_args *argv, uint32_t flags);
33 static int cmd_sleep(int argc, const cmd_args *argv, uint32_t flags);
34 static int cmd_crash(int argc, const cmd_args *argv, uint32_t flags);
35 static int cmd_stackstomp(int argc, const cmd_args *argv, uint32_t flags);
36 static int cmd_cmdline(int argc, const cmd_args *argv, uint32_t flags);
37 
38 STATIC_COMMAND_START
39 #if LK_DEBUGLEVEL > 0
40 STATIC_COMMAND_MASKED("dw", "display memory in words", &cmd_display_mem, CMD_AVAIL_ALWAYS)
41 STATIC_COMMAND_MASKED("dh", "display memory in halfwords", &cmd_display_mem, CMD_AVAIL_ALWAYS)
42 STATIC_COMMAND_MASKED("db", "display memory in bytes", &cmd_display_mem, CMD_AVAIL_ALWAYS)
43 STATIC_COMMAND_MASKED("mw", "modify word of memory", &cmd_modify_mem, CMD_AVAIL_ALWAYS)
44 STATIC_COMMAND_MASKED("mh", "modify halfword of memory", &cmd_modify_mem, CMD_AVAIL_ALWAYS)
45 STATIC_COMMAND_MASKED("mb", "modify byte of memory", &cmd_modify_mem, CMD_AVAIL_ALWAYS)
46 STATIC_COMMAND_MASKED("fw", "fill range of memory by word", &cmd_fill_mem, CMD_AVAIL_ALWAYS)
47 STATIC_COMMAND_MASKED("fh", "fill range of memory by halfword", &cmd_fill_mem, CMD_AVAIL_ALWAYS)
48 STATIC_COMMAND_MASKED("fb", "fill range of memory by byte", &cmd_fill_mem, CMD_AVAIL_ALWAYS)
49 STATIC_COMMAND_MASKED("mc", "copy a range of memory", &cmd_copy_mem, CMD_AVAIL_ALWAYS)
50 STATIC_COMMAND("crash", "intentionally crash", &cmd_crash)
51 STATIC_COMMAND("stackstomp", "intentionally overrun the stack", &cmd_stackstomp)
52 #endif
53 #if LK_DEBUGLEVEL > 1
54 STATIC_COMMAND("mtest", "simple memory test", &cmd_memtest)
55 #endif
56 STATIC_COMMAND("cmdline", "display kernel commandline", &cmd_cmdline)
57 STATIC_COMMAND("sleep", "sleep number of seconds", &cmd_sleep)
58 STATIC_COMMAND("sleepm", "sleep number of milliseconds", &cmd_sleep)
59 STATIC_COMMAND_END(mem);
60 
cmd_display_mem(int argc,const cmd_args * argv,uint32_t flags)61 static int cmd_display_mem(int argc, const cmd_args *argv, uint32_t flags)
62 {
63     /* save the last address and len so we can continue where we left off */
64     static unsigned long address;
65     static size_t len;
66 
67     if (argc < 3 && len == 0) {
68         printf("not enough arguments\n");
69         printf("%s [-l] [-b] [address] [length]\n", argv[0].str);
70         return -1;
71     }
72 
73     int size;
74     if (strcmp(argv[0].str, "dw") == 0) {
75         size = 4;
76     } else if (strcmp(argv[0].str, "dh") == 0) {
77         size = 2;
78     } else {
79         size = 1;
80     }
81 
82     uint byte_order = BYTE_ORDER;
83     int argindex = 1;
84     bool read_address = false;
85     while (argc > argindex) {
86         if (!strcmp(argv[argindex].str, "-l")) {
87             byte_order = LITTLE_ENDIAN;
88         } else if (!strcmp(argv[argindex].str, "-b")) {
89             byte_order = BIG_ENDIAN;
90         } else if (!read_address) {
91             address = argv[argindex].u;
92             read_address = true;
93         } else {
94             len = argv[argindex].u;
95         }
96 
97         argindex++;
98     }
99 
100     unsigned long stop = address + len;
101     int count = 0;
102 
103     if ((address & (size - 1)) != 0) {
104         printf("unaligned address, cannot display\n");
105         return -1;
106     }
107 
108     /* preflight the start address to see if it's mapped */
109     if (vaddr_to_paddr((void *)address) == 0) {
110         printf("ERROR: address 0x%lx is unmapped\n", address);
111         return -1;
112     }
113 
114     for ( ; address < stop; address += size) {
115         if (count == 0)
116             printf("0x%08lx: ", address);
117         switch (size) {
118             case 4: {
119                 uint32_t val = (byte_order != BYTE_ORDER) ?
120                                SWAP_32(*(uint32_t *)address) :
121                                *(uint32_t *)address;
122                 printf("%08x ", val);
123                 break;
124             }
125             case 2: {
126                 uint16_t val = (byte_order != BYTE_ORDER) ?
127                                SWAP_16(*(uint16_t *)address) :
128                                *(uint16_t *)address;
129                 printf("%04hx ", val);
130                 break;
131             }
132             case 1:
133                 printf("%02hhx ", *(uint8_t *)address);
134                 break;
135         }
136         count += size;
137         if (count == 16) {
138             printf("\n");
139             count = 0;
140         }
141     }
142 
143     if (count != 0)
144         printf("\n");
145 
146     return 0;
147 }
148 
cmd_modify_mem(int argc,const cmd_args * argv,uint32_t flags)149 static int cmd_modify_mem(int argc, const cmd_args *argv, uint32_t flags)
150 {
151     int size;
152 
153     if (argc < 3) {
154         printf("not enough arguments\n");
155         printf("%s <address> <val>\n", argv[0].str);
156         return -1;
157     }
158 
159     if (strcmp(argv[0].str, "mw") == 0) {
160         size = 4;
161     } else if (strcmp(argv[0].str, "mh") == 0) {
162         size = 2;
163     } else {
164         size = 1;
165     }
166 
167     unsigned long address = argv[1].u;
168     unsigned long val = argv[2].u;
169 
170     if ((address & (size - 1)) != 0) {
171         printf("unaligned address, cannot modify\n");
172         return -1;
173     }
174 
175     switch (size) {
176         case 4:
177             *(uint32_t *)address = (uint32_t)val;
178             break;
179         case 2:
180             *(uint16_t *)address = (uint16_t)val;
181             break;
182         case 1:
183             *(uint8_t *)address = (uint8_t)val;
184             break;
185     }
186 
187     return 0;
188 }
189 
cmd_fill_mem(int argc,const cmd_args * argv,uint32_t flags)190 static int cmd_fill_mem(int argc, const cmd_args *argv, uint32_t flags)
191 {
192     int size;
193 
194     if (argc < 4) {
195         printf("not enough arguments\n");
196         printf("%s <address> <len> <val>\n", argv[0].str);
197         return -1;
198     }
199 
200     if (strcmp(argv[0].str, "fw") == 0) {
201         size = 4;
202     } else if (strcmp(argv[0].str, "fh") == 0) {
203         size = 2;
204     } else {
205         size = 1;
206     }
207 
208     unsigned long address = argv[1].u;
209     unsigned long len = argv[2].u;
210     unsigned long stop = address + len;
211     unsigned long val = argv[3].u;
212 
213     if ((address & (size - 1)) != 0) {
214         printf("unaligned address, cannot modify\n");
215         return -1;
216     }
217 
218     for ( ; address < stop; address += size) {
219         switch (size) {
220             case 4:
221                 *(uint32_t *)address = (uint32_t)val;
222                 break;
223             case 2:
224                 *(uint16_t *)address = (uint16_t)val;
225                 break;
226             case 1:
227                 *(uint8_t *)address = (uint8_t)val;
228                 break;
229         }
230     }
231 
232     return 0;
233 }
234 
cmd_copy_mem(int argc,const cmd_args * argv,uint32_t flags)235 static int cmd_copy_mem(int argc, const cmd_args *argv, uint32_t flags)
236 {
237     if (argc < 4) {
238         printf("not enough arguments\n");
239         printf("%s <source address> <target address> <len>\n", argv[0].str);
240         return -1;
241     }
242 
243     addr_t source = argv[1].u;
244     addr_t target = argv[2].u;
245     size_t len = argv[3].u;
246 
247     memcpy((void *)target, (const void *)source, len);
248 
249     return 0;
250 }
251 
cmd_memtest(int argc,const cmd_args * argv,uint32_t flags)252 static int cmd_memtest(int argc, const cmd_args *argv, uint32_t flags)
253 {
254     if (argc < 3) {
255         printf("not enough arguments\n");
256         printf("%s <base> <len>\n", argv[0].str);
257         return -1;
258     }
259 
260     uint32_t *ptr;
261     size_t len;
262 
263     ptr = (uint32_t *)argv[1].u;
264     len = (size_t)argv[2].u;
265 
266     size_t i;
267     // write out
268     printf("writing first pass...");
269     for (i = 0; i < len / 4; i++) {
270         ptr[i] = static_cast<uint32_t>(i);
271     }
272     printf("done\n");
273 
274     // verify
275     printf("verifying...");
276     for (i = 0; i < len / 4; i++) {
277         if (ptr[i] != i)
278             printf("error at %p\n", &ptr[i]);
279     }
280     printf("done\n");
281 
282     return 0;
283 }
284 
cmd_sleep(int argc,const cmd_args * argv,uint32_t flags)285 static int cmd_sleep(int argc, const cmd_args *argv, uint32_t flags)
286 {
287     zx_duration_t t = ZX_SEC(1); /* default to 1 second */
288 
289     if (argc >= 2) {
290         t = ZX_MSEC(argv[1].u);
291         if (!strcmp(argv[0].str, "sleep"))
292             t = zx_duration_mul_int64(t, 1000);
293     }
294 
295     thread_sleep_relative(t);
296 
297     return 0;
298 }
299 
crash_thread(void *)300 static int crash_thread(void *)
301 {
302     /* should crash */
303     volatile uint32_t *ptr = (volatile uint32_t *)1u;
304     *ptr = 1;
305 
306     return 0;
307 }
308 
cmd_crash(int argc,const cmd_args * argv,uint32_t flags)309 static int cmd_crash(int argc, const cmd_args *argv, uint32_t flags)
310 {
311     if (argc > 1) {
312         if (!strcmp(argv[1].str, "thread")) {
313             thread_t *t = thread_create("crasher", &crash_thread, NULL, DEFAULT_PRIORITY);
314             thread_resume(t);
315 
316             thread_join(t, NULL, ZX_TIME_INFINITE);
317             return 0;
318         }
319     }
320 
321     crash_thread(nullptr);
322 
323     /* if it didn't, panic the system */
324     panic("crash");
325 
326     return 0;
327 }
328 
stomp_stack(size_t size)329 __attribute__((noinline)) static void stomp_stack(size_t size) {
330     // -Wvla prevents VLAs but not explicit alloca.
331     // Neither is allowed anywhere in the kernel outside this test code.
332     void* death = __builtin_alloca(size); // OK in test-only code.
333     memset(death, 0xaa, size);
334     thread_sleep_relative(ZX_USEC(1));
335 }
336 
cmd_stackstomp(int argc,const cmd_args * argv,uint32_t flags)337 static int cmd_stackstomp(int argc, const cmd_args *argv, uint32_t flags)
338 {
339     for (size_t i = 0; i < DEFAULT_STACK_SIZE * 2; i++)
340         stomp_stack(i);
341 
342     printf("survived.\n");
343 
344     return 0;
345 }
346 
347 #define DEBUG_CMDLINE_MAX 1024
cmd_cmdline(int argc,const cmd_args * argv,uint32_t flags)348 static int cmd_cmdline(int argc, const cmd_args *argv, uint32_t flags)
349 {
350     if (argc == 1) {
351         char cmdline_buf[DEBUG_CMDLINE_MAX];
352         memset(cmdline_buf, 0, DEBUG_CMDLINE_MAX);
353         const char* cmdline = cmdline_get(NULL);
354         for (size_t i = 0; i < DEBUG_CMDLINE_MAX; i++) {
355             if (cmdline[i] == '\0') {
356                 if (cmdline[i+1] == '\0') {
357                     break;
358                 }
359                 cmdline_buf[i] = ' ';
360             } else {
361                 cmdline_buf[i] = cmdline[i];
362             }
363         }
364         printf("cmdline: %s\n", cmdline_buf);
365     } else {
366         const char* key = argv[1].str;
367         const char* val = cmdline_get(key);
368         if (!val) {
369             printf("cmdline: %s not found\n", key);
370         } else {
371             printf("cmdline: %s=%s\n", key, val);
372         }
373     }
374 
375     return 0;
376 }
377