rev 8113 : 8076475: Misuses of strncpy/strncat
Summary: Various small fixes around strncpy and strncat
Reviewed-by: dsamersoff
1 /*
2 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24 #include <stdarg.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <fcntl.h>
29 #include <thread_db.h>
30 #include "libproc_impl.h"
31
32 #define SA_ALTROOT "SA_ALTROOT"
33
34 int pathmap_open(const char* name) {
35 static const char *alt_root = NULL;
36 static int alt_root_initialized = 0;
37
38 int fd;
39 char alt_path[PATH_MAX + 1], *alt_path_end;
40 const char *s;
41
42 if (!alt_root_initialized) {
43 alt_root_initialized = -1;
44 alt_root = getenv(SA_ALTROOT);
45 }
46
47 if (alt_root == NULL) {
48 return open(name, O_RDONLY);
49 }
50
51 strcpy(alt_path, alt_root);
52 alt_path_end = alt_path + strlen(alt_path);
53
54 // Strip path items one by one and try to open file with alt_root prepended
55 s = name;
56 while (1) {
57 strcat(alt_path, s);
58 s += 1;
59
60 fd = open(alt_path, O_RDONLY);
61 if (fd >= 0) {
62 print_debug("path %s substituted for %s\n", alt_path, name);
63 return fd;
64 }
65
66 // Linker always put full path to solib to process, so we can rely
67 // on presence of /. If slash is not present, it means, that SOlib doesn't
68 // physically exist (e.g. linux-gate.so) and we fail opening it anyway
69 if ((s = strchr(s, '/')) == NULL) {
70 break;
71 }
72
73 *alt_path_end = 0;
74 }
75
76 return -1;
77 }
78
79 static bool _libsaproc_debug;
80
81 void print_debug(const char* format,...) {
82 if (_libsaproc_debug) {
83 va_list alist;
84
85 va_start(alist, format);
86 fputs("libsaproc DEBUG: ", stderr);
87 vfprintf(stderr, format, alist);
88 va_end(alist);
89 }
90 }
91
92 void print_error(const char* format,...) {
93 va_list alist;
94 va_start(alist, format);
95 fputs("ERROR: ", stderr);
96 vfprintf(stderr, format, alist);
97 va_end(alist);
98 }
99
100 bool is_debug() {
101 return _libsaproc_debug;
102 }
103
104 // initialize libproc
105 bool init_libproc(bool debug) {
106 // init debug mode
107 _libsaproc_debug = debug;
108
109 // initialize the thread_db library
110 if (td_init() != TD_OK) {
111 print_debug("libthread_db's td_init failed\n");
112 return false;
113 }
114
115 return true;
116 }
117
118 static void destroy_lib_info(struct ps_prochandle* ph) {
119 lib_info* lib = ph->libs;
120 while (lib) {
121 lib_info *next = lib->next;
122 if (lib->symtab) {
123 destroy_symtab(lib->symtab);
124 }
125 free(lib);
126 lib = next;
127 }
128 }
129
130 static void destroy_thread_info(struct ps_prochandle* ph) {
131 thread_info* thr = ph->threads;
132 while (thr) {
133 thread_info *next = thr->next;
134 free(thr);
135 thr = next;
136 }
137 }
138
139 // ps_prochandle cleanup
140
141 // ps_prochandle cleanup
142 void Prelease(struct ps_prochandle* ph) {
143 // do the "derived class" clean-up first
144 ph->ops->release(ph);
145 destroy_lib_info(ph);
146 destroy_thread_info(ph);
147 free(ph);
148 }
149
150 lib_info* add_lib_info(struct ps_prochandle* ph, const char* libname, uintptr_t base) {
151 return add_lib_info_fd(ph, libname, -1, base);
152 }
153
154 lib_info* add_lib_info_fd(struct ps_prochandle* ph, const char* libname, int fd, uintptr_t base) {
155 lib_info* newlib;
156
157 if ( (newlib = (lib_info*) calloc(1, sizeof(struct lib_info))) == NULL) {
158 print_debug("can't allocate memory for lib_info\n");
159 return NULL;
160 }
161
162 strncpy(newlib->name, libname, sizeof(newlib->name));
163 newlib->base = base;
164
165 if (fd == -1) {
166 if ( (newlib->fd = pathmap_open(newlib->name)) < 0) {
167 print_debug("can't open shared object %s\n", newlib->name);
168 free(newlib);
169 return NULL;
170 }
171 } else {
172 newlib->fd = fd;
173 }
174
175 // check whether we have got an ELF file. /proc/<pid>/map
176 // gives out all file mappings and not just shared objects
177 if (is_elf_file(newlib->fd) == false) {
178 close(newlib->fd);
179 free(newlib);
180 return NULL;
181 }
182
183 newlib->symtab = build_symtab(newlib->fd, libname);
184 if (newlib->symtab == NULL) {
185 print_debug("symbol table build failed for %s\n", newlib->name);
186 }
187
188 // even if symbol table building fails, we add the lib_info.
189 // This is because we may need to read from the ELF file for core file
190 // address read functionality. lookup_symbol checks for NULL symtab.
191 if (ph->libs) {
192 ph->lib_tail->next = newlib;
193 ph->lib_tail = newlib;
194 } else {
195 ph->libs = ph->lib_tail = newlib;
196 }
197 ph->num_libs++;
198
199 return newlib;
200 }
201
202 // lookup for a specific symbol
203 uintptr_t lookup_symbol(struct ps_prochandle* ph, const char* object_name,
204 const char* sym_name) {
205 // ignore object_name. search in all libraries
206 // FIXME: what should we do with object_name?? The library names are obtained
207 // by parsing /proc/<pid>/maps, which may not be the same as object_name.
208 // What we need is a utility to map object_name to real file name, something
209 // dlopen() does by looking at LD_LIBRARY_PATH and /etc/ld.so.cache. For
210 // now, we just ignore object_name and do a global search for the symbol.
211
212 lib_info* lib = ph->libs;
213 while (lib) {
214 if (lib->symtab) {
215 uintptr_t res = search_symbol(lib->symtab, lib->base, sym_name, NULL);
216 if (res) return res;
217 }
218 lib = lib->next;
219 }
220
221 print_debug("lookup failed for symbol '%s' in obj '%s'\n",
222 sym_name, object_name);
223 return (uintptr_t) NULL;
224 }
225
226
227 const char* symbol_for_pc(struct ps_prochandle* ph, uintptr_t addr, uintptr_t* poffset) {
228 const char* res = NULL;
229 lib_info* lib = ph->libs;
230 while (lib) {
231 if (lib->symtab && addr >= lib->base) {
232 res = nearest_symbol(lib->symtab, addr - lib->base, poffset);
233 if (res) return res;
234 }
235 lib = lib->next;
236 }
237 return NULL;
238 }
239
240 // add a thread to ps_prochandle
241 thread_info* add_thread_info(struct ps_prochandle* ph, pthread_t pthread_id, lwpid_t lwp_id) {
242 thread_info* newthr;
243 if ( (newthr = (thread_info*) calloc(1, sizeof(thread_info))) == NULL) {
244 print_debug("can't allocate memory for thread_info\n");
245 return NULL;
246 }
247
248 // initialize thread info
249 newthr->pthread_id = pthread_id;
250 newthr->lwp_id = lwp_id;
251
252 // add new thread to the list
253 newthr->next = ph->threads;
254 ph->threads = newthr;
255 ph->num_threads++;
256 return newthr;
257 }
258
259
260 // struct used for client data from thread_db callback
261 struct thread_db_client_data {
262 struct ps_prochandle* ph;
263 thread_info_callback callback;
264 };
265
266 // callback function for libthread_db
267 static int thread_db_callback(const td_thrhandle_t *th_p, void *data) {
268 struct thread_db_client_data* ptr = (struct thread_db_client_data*) data;
269 td_thrinfo_t ti;
270 td_err_e err;
271
272 memset(&ti, 0, sizeof(ti));
273 err = td_thr_get_info(th_p, &ti);
274 if (err != TD_OK) {
275 print_debug("libthread_db : td_thr_get_info failed, can't get thread info\n");
276 return err;
277 }
278
279 print_debug("thread_db : pthread %d (lwp %d)\n", ti.ti_tid, ti.ti_lid);
280
281 if (ptr->callback(ptr->ph, ti.ti_tid, ti.ti_lid) != true)
282 return TD_ERR;
283
284 return TD_OK;
285 }
286
287 // read thread_info using libthread_db
288 bool read_thread_info(struct ps_prochandle* ph, thread_info_callback cb) {
289 struct thread_db_client_data mydata;
290 td_thragent_t* thread_agent = NULL;
291 if (td_ta_new(ph, &thread_agent) != TD_OK) {
292 print_debug("can't create libthread_db agent\n");
293 return false;
294 }
295
296 mydata.ph = ph;
297 mydata.callback = cb;
298
299 // we use libthread_db iterator to iterate thru list of threads.
300 if (td_ta_thr_iter(thread_agent, thread_db_callback, &mydata,
301 TD_THR_ANY_STATE, TD_THR_LOWEST_PRIORITY,
302 TD_SIGNO_MASK, TD_THR_ANY_USER_FLAGS) != TD_OK) {
303 td_ta_delete(thread_agent);
304 return false;
305 }
306
307 // delete thread agent
308 td_ta_delete(thread_agent);
309 return true;
310 }
311
312
313 // get number of threads
314 int get_num_threads(struct ps_prochandle* ph) {
315 return ph->num_threads;
316 }
317
318 // get lwp_id of n'th thread
319 lwpid_t get_lwp_id(struct ps_prochandle* ph, int index) {
320 int count = 0;
321 thread_info* thr = ph->threads;
322 while (thr) {
323 if (count == index) {
324 return thr->lwp_id;
325 }
326 count++;
327 thr = thr->next;
328 }
329 return -1;
330 }
331
332 // get regs for a given lwp
333 bool get_lwp_regs(struct ps_prochandle* ph, lwpid_t lwp_id, struct user_regs_struct* regs) {
334 return ph->ops->get_lwp_regs(ph, lwp_id, regs);
335 }
336
337 // get number of shared objects
338 int get_num_libs(struct ps_prochandle* ph) {
339 return ph->num_libs;
340 }
341
342 // get name of n'th solib
343 const char* get_lib_name(struct ps_prochandle* ph, int index) {
344 int count = 0;
345 lib_info* lib = ph->libs;
346 while (lib) {
347 if (count == index) {
348 return lib->name;
349 }
350 count++;
351 lib = lib->next;
352 }
353 return NULL;
354 }
355
356 // get base address of a lib
357 uintptr_t get_lib_base(struct ps_prochandle* ph, int index) {
358 int count = 0;
359 lib_info* lib = ph->libs;
360 while (lib) {
361 if (count == index) {
362 return lib->base;
363 }
364 count++;
365 lib = lib->next;
366 }
367 return (uintptr_t)NULL;
368 }
369
370 bool find_lib(struct ps_prochandle* ph, const char *lib_name) {
371 lib_info *p = ph->libs;
372 while (p) {
373 if (strcmp(p->name, lib_name) == 0) {
374 return true;
375 }
376 p = p->next;
377 }
378 return false;
379 }
380
381 //--------------------------------------------------------------------------
382 // proc service functions
383
384 // get process id
385 pid_t ps_getpid(struct ps_prochandle *ph) {
386 return ph->pid;
387 }
388
389 // ps_pglobal_lookup() looks up the symbol sym_name in the symbol table
390 // of the load object object_name in the target process identified by ph.
391 // It returns the symbol's value as an address in the target process in
392 // *sym_addr.
393
394 ps_err_e ps_pglobal_lookup(struct ps_prochandle *ph, const char *object_name,
395 const char *sym_name, psaddr_t *sym_addr) {
396 *sym_addr = (psaddr_t) lookup_symbol(ph, object_name, sym_name);
397 return (*sym_addr ? PS_OK : PS_NOSYM);
398 }
399
400 // read "size" bytes info "buf" from address "addr"
401 ps_err_e ps_pdread(struct ps_prochandle *ph, psaddr_t addr,
402 void *buf, size_t size) {
403 return ph->ops->p_pread(ph, (uintptr_t) addr, buf, size)? PS_OK: PS_ERR;
404 }
405
406 // write "size" bytes of data to debuggee at address "addr"
407 ps_err_e ps_pdwrite(struct ps_prochandle *ph, psaddr_t addr,
408 const void *buf, size_t size) {
409 return ph->ops->p_pwrite(ph, (uintptr_t)addr, buf, size)? PS_OK: PS_ERR;
410 }
411
412 // ------------------------------------------------------------------------
413 // Functions below this point are not yet implemented. They are here only
414 // to make the linker happy.
415
416 ps_err_e ps_lsetfpregs(struct ps_prochandle *ph, lwpid_t lid, const prfpregset_t *fpregs) {
417 print_debug("ps_lsetfpregs not implemented\n");
418 return PS_OK;
419 }
420
421 ps_err_e ps_lsetregs(struct ps_prochandle *ph, lwpid_t lid, const prgregset_t gregset) {
422 print_debug("ps_lsetregs not implemented\n");
423 return PS_OK;
424 }
425
426 ps_err_e ps_lgetfpregs(struct ps_prochandle *ph, lwpid_t lid, prfpregset_t *fpregs) {
427 print_debug("ps_lgetfpregs not implemented\n");
428 return PS_OK;
429 }
430
431 ps_err_e ps_lgetregs(struct ps_prochandle *ph, lwpid_t lid, prgregset_t gregset) {
432 print_debug("ps_lgetfpregs not implemented\n");
433 return PS_OK;
434 }
435
436 // new libthread_db of NPTL seem to require this symbol
437 ps_err_e ps_get_thread_area() {
438 print_debug("ps_get_thread_area not implemented\n");
439 return PS_OK;
440 }
--- EOF ---