xref: /netbsd-src/sys/kern/core_elf32.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: core_elf32.c,v 1.22 2005/12/08 03:05:40 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed for the NetBSD Project by
20  *	Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 /*
39  * core_elf32.c/core_elf64.c: Support for the Elf32/Elf64 core file format.
40  */
41 
42 #include <sys/cdefs.h>
43 __KERNEL_RCSID(1, "$NetBSD: core_elf32.c,v 1.22 2005/12/08 03:05:40 thorpej Exp $");
44 
45 /* If not included by core_elf64.c, ELFSIZE won't be defined. */
46 #ifndef ELFSIZE
47 #define	ELFSIZE		32
48 #endif
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/proc.h>
53 #include <sys/vnode.h>
54 #include <sys/exec.h>
55 #include <sys/exec_elf.h>
56 #include <sys/ptrace.h>
57 #include <sys/malloc.h>
58 
59 #include <machine/reg.h>
60 
61 #include <uvm/uvm_extern.h>
62 
63 struct countsegs_state {
64 	int	npsections;
65 };
66 
67 static int	ELFNAMEEND(coredump_countsegs)(struct proc *, void *,
68 		    struct uvm_coredump_state *);
69 
70 struct writesegs_state {
71 	Elf_Phdr *psections;
72 	off_t	secoff;
73 };
74 
75 static int	ELFNAMEEND(coredump_writeseghdrs)(struct proc *, void *,
76 		    struct uvm_coredump_state *);
77 
78 static int	ELFNAMEEND(coredump_notes)(struct proc *, struct lwp *, void *,
79 		    size_t *);
80 static int	ELFNAMEEND(coredump_note)(struct proc *, struct lwp *, void *,
81 		    size_t *);
82 
83 #define	ELFROUNDSIZE	4	/* XXX Should it be sizeof(Elf_Word)? */
84 #define	elfround(x)	roundup((x), ELFROUNDSIZE)
85 
86 int
87 ELFNAMEEND(coredump)(struct lwp *l, void *cookie)
88 {
89 	struct proc *p;
90 	Elf_Ehdr ehdr;
91 	Elf_Phdr phdr, *psections;
92 	struct countsegs_state cs;
93 	struct writesegs_state ws;
94 	off_t notestart, secstart, offset;
95 	size_t notesize;
96 	int error, i;
97 
98 	psections = NULL;
99 	p = l->l_proc;
100 	/*
101 	 * We have to make a total of 3 passes across the map:
102 	 *
103 	 *	1. Count the number of map entries (the number of
104 	 *	   PT_LOAD sections).
105 	 *
106 	 *	2. Write the P-section headers.
107 	 *
108 	 *	3. Write the P-sections.
109 	 */
110 
111 	/* Pass 1: count the entries. */
112 	cs.npsections = 0;
113 	error = uvm_coredump_walkmap(p, NULL,
114 	    ELFNAMEEND(coredump_countsegs), &cs);
115 	if (error)
116 		goto out;
117 
118 	/* Count the PT_NOTE section. */
119 	cs.npsections++;
120 
121 	/* Get the size of the notes. */
122 	error = ELFNAMEEND(coredump_notes)(p, l, NULL, &notesize);
123 	if (error)
124 		goto out;
125 
126 	memset(&ehdr.e_ident[EI_PAD], 0, sizeof(ehdr.e_ident) - EI_PAD);
127 	memcpy(ehdr.e_ident, ELFMAG, SELFMAG);
128 #if ELFSIZE == 32
129 	ehdr.e_ident[EI_CLASS] = ELFCLASS32;
130 #elif ELFSIZE == 64
131 	ehdr.e_ident[EI_CLASS] = ELFCLASS64;
132 #endif
133 	ehdr.e_ident[EI_DATA] = ELFDEFNNAME(MACHDEP_ENDIANNESS);
134 	ehdr.e_ident[EI_VERSION] = EV_CURRENT;
135 	/* XXX Should be the OSABI/ABI version of the executable. */
136 	ehdr.e_ident[EI_OSABI] = ELFOSABI_SYSV;
137 	ehdr.e_ident[EI_ABIVERSION] = 0;
138 
139 	ehdr.e_type = ET_CORE;
140 	/* XXX This should be the e_machine of the executable. */
141 	ehdr.e_machine = ELFDEFNNAME(MACHDEP_ID);
142 	ehdr.e_version = EV_CURRENT;
143 	ehdr.e_entry = 0;
144 	ehdr.e_phoff = sizeof(ehdr);
145 	ehdr.e_shoff = 0;
146 	ehdr.e_flags = 0;
147 	ehdr.e_ehsize = sizeof(ehdr);
148 	ehdr.e_phentsize = sizeof(Elf_Phdr);
149 	ehdr.e_phnum = cs.npsections;
150 	ehdr.e_shentsize = 0;
151 	ehdr.e_shnum = 0;
152 	ehdr.e_shstrndx = 0;
153 
154 	/* Write out the ELF header. */
155 	error = coredump_write(cookie, UIO_SYSSPACE, &ehdr, sizeof(ehdr));
156 	if (error)
157 		goto out;
158 
159 	offset = sizeof(ehdr);
160 
161 	notestart = offset + sizeof(phdr) * cs.npsections;
162 	secstart = notestart + notesize;
163 
164 	psections = malloc(cs.npsections * sizeof(Elf_Phdr),
165 	    M_TEMP, M_WAITOK|M_ZERO);
166 
167 	/* Pass 2: now write the P-section headers. */
168 	ws.secoff = secstart;
169 	ws.psections = psections;
170 	error = uvm_coredump_walkmap(p, cookie,
171 	    ELFNAMEEND(coredump_writeseghdrs), &ws);
172 	if (error)
173 		goto out;
174 
175 	/* Write out the PT_NOTE header. */
176 	ws.psections->p_type = PT_NOTE;
177 	ws.psections->p_offset = notestart;
178 	ws.psections->p_vaddr = 0;
179 	ws.psections->p_paddr = 0;
180 	ws.psections->p_filesz = notesize;
181 	ws.psections->p_memsz = 0;
182 	ws.psections->p_flags = PF_R;
183 	ws.psections->p_align = ELFROUNDSIZE;
184 
185 	error = coredump_write(cookie, UIO_SYSSPACE, psections,
186 	    cs.npsections * sizeof(Elf_Phdr));
187 	if (error)
188 		goto out;
189 
190 #ifdef DIAGNOSTIC
191 	offset += cs.npsections * sizeof(Elf_Phdr);
192 	if (offset != notestart)
193 		panic("coredump: offset %lld != notestart %lld",
194 		    (long long) offset, (long long) notestart);
195 #endif
196 
197 	/* Write out the notes. */
198 	error = ELFNAMEEND(coredump_notes)(p, l, cookie, &notesize);
199 	if (error)
200 		goto out;
201 
202 #ifdef DIAGNOSTIC
203 	offset += notesize;
204 	if (offset != secstart)
205 		panic("coredump: offset %lld != secstart %lld",
206 		    (long long) offset, (long long) secstart);
207 #endif
208 
209 	/* Pass 3: finally, write the sections themselves. */
210 	for (i = 0; i < cs.npsections - 1; i++) {
211 		if (psections[i].p_filesz == 0)
212 			continue;
213 
214 #ifdef DIAGNOSTIC
215 		if (offset != psections[i].p_offset)
216 			panic("coredump: offset %lld != p_offset[%d] %lld",
217 			    (long long) offset, i,
218 			    (long long) psections[i].p_filesz);
219 #endif
220 
221 		error = coredump_write(cookie, UIO_USERSPACE,
222 		    (void *)(vaddr_t)psections[i].p_vaddr,
223 		    psections[i].p_filesz);
224 		if (error)
225 			goto out;
226 
227 #ifdef DIAGNOSTIC
228 		offset += psections[i].p_filesz;
229 #endif
230 	}
231 
232   out:
233 	if (psections)
234 		free(psections, M_TEMP);
235 	return (error);
236 }
237 
238 static int
239 ELFNAMEEND(coredump_countsegs)(struct proc *p, void *iocookie,
240     struct uvm_coredump_state *us)
241 {
242 	struct countsegs_state *cs = us->cookie;
243 
244 	cs->npsections++;
245 	return (0);
246 }
247 
248 static int
249 ELFNAMEEND(coredump_writeseghdrs)(struct proc *p, void *iocookie,
250     struct uvm_coredump_state *us)
251 {
252 	struct writesegs_state *ws = us->cookie;
253 	Elf_Phdr phdr;
254 	vsize_t size, realsize;
255 	vaddr_t end;
256 	int error;
257 
258 	size = us->end - us->start;
259 	realsize = us->realend - us->start;
260 	end = us->realend;
261 
262 	while (realsize > 0) {
263 		long buf[1024 / sizeof(long)];
264 		size_t slen = realsize > sizeof(buf) ? sizeof(buf) : realsize;
265 		const long *ep;
266 		int i;
267 
268 		end -= slen;
269 		if ((error = copyin_proc(p, (void *)end, buf, slen)) != 0)
270 			return error;
271 
272 		ep = (const long *) &buf[slen / sizeof(buf[0])];
273 		for (i = 0, ep--; buf <= ep; ep--, i++) {
274 			if (*ep)
275 				break;
276 		}
277 		realsize -= i * sizeof(buf[0]);
278 		if (i * sizeof(buf[0]) < slen)
279 			break;
280 	}
281 
282 	phdr.p_type = PT_LOAD;
283 	phdr.p_offset = ws->secoff;
284 	phdr.p_vaddr = us->start;
285 	phdr.p_paddr = 0;
286 	phdr.p_filesz = realsize;
287 	phdr.p_memsz = size;
288 	phdr.p_flags = 0;
289 	if (us->prot & VM_PROT_READ)
290 		phdr.p_flags |= PF_R;
291 	if (us->prot & VM_PROT_WRITE)
292 		phdr.p_flags |= PF_W;
293 	if (us->prot & VM_PROT_EXECUTE)
294 		phdr.p_flags |= PF_X;
295 	phdr.p_align = PAGE_SIZE;
296 
297 	ws->secoff += phdr.p_filesz;
298 	*ws->psections++ = phdr;
299 
300 	return (0);
301 }
302 
303 static int
304 ELFNAMEEND(coredump_notes)(struct proc *p, struct lwp *l,
305     void *iocookie, size_t *sizep)
306 {
307 	struct netbsd_elfcore_procinfo cpi;
308 	Elf_Nhdr nhdr;
309 	size_t size, notesize;
310 	int error;
311 	struct lwp *l0;
312 
313 	size = 0;
314 
315 	/* First, write an elfcore_procinfo. */
316 	notesize = sizeof(nhdr) + elfround(sizeof(ELF_NOTE_NETBSD_CORE_NAME)) +
317 	    elfround(sizeof(cpi));
318 	if (iocookie) {
319 		cpi.cpi_version = NETBSD_ELFCORE_PROCINFO_VERSION;
320 		cpi.cpi_cpisize = sizeof(cpi);
321 		cpi.cpi_signo = p->p_sigctx.ps_signo;
322 		cpi.cpi_sigcode = p->p_sigctx.ps_code;
323 		cpi.cpi_siglwp = p->p_sigctx.ps_lwp;
324 
325 		memcpy(&cpi.cpi_sigpend, &p->p_sigctx.ps_siglist,
326 		    sizeof(cpi.cpi_sigpend));
327 		memcpy(&cpi.cpi_sigmask, &p->p_sigctx.ps_sigmask,
328 		    sizeof(cpi.cpi_sigmask));
329 		memcpy(&cpi.cpi_sigignore, &p->p_sigctx.ps_sigignore,
330 		    sizeof(cpi.cpi_sigignore));
331 		memcpy(&cpi.cpi_sigcatch, &p->p_sigctx.ps_sigcatch,
332 		    sizeof(cpi.cpi_sigcatch));
333 
334 		cpi.cpi_pid = p->p_pid;
335 		cpi.cpi_ppid = p->p_pptr->p_pid;
336 		cpi.cpi_pgrp = p->p_pgid;
337 		cpi.cpi_sid = p->p_session->s_sid;
338 
339 		cpi.cpi_ruid = p->p_cred->p_ruid;
340 		cpi.cpi_euid = p->p_ucred->cr_uid;
341 		cpi.cpi_svuid = p->p_cred->p_svuid;
342 
343 		cpi.cpi_rgid = p->p_cred->p_rgid;
344 		cpi.cpi_egid = p->p_ucred->cr_gid;
345 		cpi.cpi_svgid = p->p_cred->p_svgid;
346 
347 		cpi.cpi_nlwps = p->p_nlwps;
348 		strlcpy(cpi.cpi_name, p->p_comm, sizeof(cpi.cpi_name));
349 
350 		nhdr.n_namesz = sizeof(ELF_NOTE_NETBSD_CORE_NAME);
351 		nhdr.n_descsz = sizeof(cpi);
352 		nhdr.n_type = ELF_NOTE_NETBSD_CORE_PROCINFO;
353 
354 		error = ELFNAMEEND(coredump_writenote)(p, iocookie, &nhdr,
355 		    ELF_NOTE_NETBSD_CORE_NAME "\0\0\0", &cpi);
356 		if (error)
357 			return (error);
358 	}
359 
360 	size += notesize;
361 
362 	/* XXX Add hook for machdep per-proc notes. */
363 
364 	/*
365 	 * Now write the register info for the thread that caused the
366 	 * coredump.
367 	 */
368 	error = ELFNAMEEND(coredump_note)(p, l, iocookie, &notesize);
369 	if (error)
370 		return (error);
371 	size += notesize;
372 
373 	/*
374 	 * Now, for each LWP, write the register info and any other
375 	 * per-LWP notes.
376 	 */
377 	LIST_FOREACH(l0, &p->p_lwps, l_sibling) {
378 		if (l0 == l)		/* we've taken care of this thread */
379 			continue;
380 		error = ELFNAMEEND(coredump_note)(p, l0, iocookie, &notesize);
381 		if (error)
382 			return (error);
383 		size += notesize;
384 	}
385 
386 	*sizep = size;
387 	return (0);
388 }
389 
390 static int
391 ELFNAMEEND(coredump_note)(struct proc *p, struct lwp *l, void *iocookie,
392     size_t *sizep)
393 {
394 	Elf_Nhdr nhdr;
395 	int size, notesize, error;
396 	int namesize;
397 	char name[64+ELFROUNDSIZE];
398 	struct reg intreg;
399 #ifdef PT_GETFPREGS
400 	struct fpreg freg;
401 #endif
402 
403 	size = 0;
404 
405 	snprintf(name, sizeof(name)-ELFROUNDSIZE, "%s@%d",
406 	    ELF_NOTE_NETBSD_CORE_NAME, l->l_lid);
407 	namesize = strlen(name) + 1;
408 	memset(name + namesize, 0, elfround(namesize) - namesize);
409 
410 	notesize = sizeof(nhdr) + elfround(namesize) + elfround(sizeof(intreg));
411 	if (iocookie) {
412 		PHOLD(l);
413 		error = process_read_regs(l, &intreg);
414 		PRELE(l);
415 		if (error)
416 			return (error);
417 
418 		nhdr.n_namesz = namesize;
419 		nhdr.n_descsz = sizeof(intreg);
420 		nhdr.n_type = PT_GETREGS;
421 
422 		error = ELFNAMEEND(coredump_writenote)(p, iocookie, &nhdr,
423 		    name, &intreg);
424 		if (error)
425 			return (error);
426 
427 	}
428 	size += notesize;
429 
430 #ifdef PT_GETFPREGS
431 	notesize = sizeof(nhdr) + elfround(namesize) + elfround(sizeof(freg));
432 	if (iocookie) {
433 		PHOLD(l);
434 		error = process_read_fpregs(l, &freg);
435 		PRELE(l);
436 		if (error)
437 			return (error);
438 
439 		nhdr.n_namesz = namesize;
440 		nhdr.n_descsz = sizeof(freg);
441 		nhdr.n_type = PT_GETFPREGS;
442 
443 		error = ELFNAMEEND(coredump_writenote)(p, iocookie, &nhdr,
444 		    name, &freg);
445 		if (error)
446 			return (error);
447 	}
448 	size += notesize;
449 #endif
450 	*sizep = size;
451 	/* XXX Add hook for machdep per-LWP notes. */
452 	return (0);
453 }
454 
455 int
456 ELFNAMEEND(coredump_writenote)(struct proc *p, void *cookie, Elf_Nhdr *nhdr,
457     const char *name, void *data)
458 {
459 	int error;
460 
461 	error = coredump_write(cookie, UIO_SYSSPACE, nhdr, sizeof(*nhdr));
462 	if (error)
463 		return error;
464 
465 	error = coredump_write(cookie, UIO_SYSSPACE, name,
466 	    elfround(nhdr->n_namesz));
467 	if (error)
468 		return error;
469 
470 	return coredump_write(cookie, UIO_SYSSPACE, data, nhdr->n_descsz);
471 }
472