NetBSD/sys/kern/core_elf32.c

520 lines
13 KiB
C

/* $NetBSD: core_elf32.c,v 1.45 2014/04/02 17:19:49 matt Exp $ */
/*
* Copyright (c) 2001 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Jason R. Thorpe for Wasabi Systems, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* core_elf32.c/core_elf64.c: Support for the Elf32/Elf64 core file format.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(1, "$NetBSD: core_elf32.c,v 1.45 2014/04/02 17:19:49 matt Exp $");
#ifdef _KERNEL_OPT
#include "opt_coredump.h"
#endif
#ifndef ELFSIZE
#define ELFSIZE 32
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/exec.h>
#include <sys/exec_elf.h>
#include <sys/ptrace.h>
#include <sys/kmem.h>
#include <sys/kauth.h>
#include <machine/reg.h>
#include <uvm/uvm_extern.h>
#ifdef COREDUMP
struct writesegs_state {
Elf_Phdr *psections;
proc_t *p;
off_t secoff;
size_t npsections;
};
/*
* We need to know how big the 'notes' are before we write the main header.
* To avoid problems with double-processing we save the data.
*/
struct note_buf {
struct note_buf *nb_next;
unsigned char nb_data[4096 - sizeof (void *)];
};
struct note_state {
struct note_buf *ns_first;
struct note_buf *ns_last;
unsigned int ns_count; /* Of full buffers */
unsigned int ns_offset; /* Write point in last buffer */
};
static int ELFNAMEEND(coredump_getseghdrs)(struct uvm_coredump_state *);
static int ELFNAMEEND(coredump_notes)(struct lwp *, struct note_state *);
static int ELFNAMEEND(coredump_note)(struct lwp *, struct note_state *);
/* The 'note' section names and data are always 4-byte aligned. */
#define ELFROUNDSIZE 4 /* XXX Should it be sizeof(Elf_Word)? */
#define elf_process_read_regs CONCAT(process_read_regs, ELFSIZE)
#define elf_process_read_fpregs CONCAT(process_read_fpregs, ELFSIZE)
#define elf_reg CONCAT(process_reg, ELFSIZE)
#define elf_fpreg CONCAT(process_fpreg, ELFSIZE)
int
ELFNAMEEND(coredump)(struct lwp *l, struct coredump_iostate *cookie)
{
Elf_Ehdr ehdr;
Elf_Shdr shdr;
Elf_Phdr *psections;
size_t psectionssize;
int npsections;
struct writesegs_state ws;
off_t notestart;
size_t notesize;
int error, i;
struct note_state ns;
struct note_buf *nb;
psections = NULL;
/* Get all of the notes (mostly all the registers). */
ns.ns_first = kmem_alloc(sizeof *ns.ns_first, KM_SLEEP);
ns.ns_last = ns.ns_first;
ns.ns_count = 0;
ns.ns_offset = 0;
error = ELFNAMEEND(coredump_notes)(l, &ns);
ns.ns_last->nb_next = NULL;
if (error)
goto out;
notesize = ns.ns_count * sizeof nb->nb_data + ns.ns_offset;
/*
* We have to make a total of 3 passes across the map:
*
* 1. Count the number of map entries (the number of
* PT_LOAD sections in the dump).
*
* 2. Write the P-section headers.
*
* 3. Write the P-sections.
*/
/* Pass 1: count the entries. */
npsections = uvm_coredump_count_segs(l->l_proc);
/* Allow for the PT_NOTE section. */
npsections++;
/* Build the main elf header */
memset(&ehdr.e_ident[EI_PAD], 0, sizeof(ehdr.e_ident) - EI_PAD);
memcpy(ehdr.e_ident, ELFMAG, SELFMAG);
#if ELFSIZE == 32
ehdr.e_ident[EI_CLASS] = ELFCLASS32;
#elif ELFSIZE == 64
ehdr.e_ident[EI_CLASS] = ELFCLASS64;
#endif
ehdr.e_ident[EI_DATA] = ELFDEFNNAME(MACHDEP_ENDIANNESS);
ehdr.e_ident[EI_VERSION] = EV_CURRENT;
/* XXX Should be the OSABI/ABI version of the executable. */
ehdr.e_ident[EI_OSABI] = ELFOSABI_SYSV;
ehdr.e_ident[EI_ABIVERSION] = 0;
ehdr.e_type = ET_CORE;
/* XXX This should be the e_machine of the executable. */
ehdr.e_machine = ELFDEFNNAME(MACHDEP_ID);
ehdr.e_version = EV_CURRENT;
ehdr.e_entry = 0;
ehdr.e_flags = 0;
ehdr.e_ehsize = sizeof(ehdr);
ehdr.e_phentsize = sizeof(Elf_Phdr);
if (npsections < PN_XNUM) {
ehdr.e_phnum = npsections;
ehdr.e_shentsize = 0;
ehdr.e_shnum = 0;
ehdr.e_shoff = 0;
ehdr.e_phoff = sizeof(ehdr);
} else {
ehdr.e_phnum = PN_XNUM;
ehdr.e_shentsize = sizeof(Elf_Shdr);
ehdr.e_shnum = 1;
ehdr.e_shoff = sizeof(ehdr);
ehdr.e_phoff = sizeof(ehdr) + sizeof(shdr);
}
ehdr.e_shstrndx = 0;
#ifdef ELF_MD_COREDUMP_SETUP
ELF_MD_COREDUMP_SETUP(l, &ehdr);
#endif
/* Write out the ELF header. */
error = coredump_write(cookie, UIO_SYSSPACE, &ehdr, sizeof(ehdr));
if (error)
goto out;
/* Write out sections, if needed */
if (npsections >= PN_XNUM) {
memset(&shdr, 0, sizeof(shdr));
shdr.sh_type = SHT_NULL;
shdr.sh_info = npsections;
error = coredump_write(cookie, UIO_SYSSPACE, &shdr,
sizeof(shdr));
if (error)
goto out;
}
psectionssize = npsections * sizeof(*psections);
notestart = ehdr.e_phoff + psectionssize;
psections = kmem_zalloc(psectionssize, KM_SLEEP);
/* Pass 2: now find the P-section headers. */
ws.secoff = notestart + notesize;
ws.psections = psections;
ws.npsections = npsections - 1;
ws.p = l->l_proc;
error = uvm_coredump_walkmap(l->l_proc, ELFNAMEEND(coredump_getseghdrs),
&ws);
if (error)
goto out;
if (ws.npsections != 0) {
/* A section went away */
error = ENOMEM;
goto out;
}
/* Add the PT_NOTE header after the P-section headers. */
ws.psections->p_type = PT_NOTE;
ws.psections->p_offset = notestart;
ws.psections->p_vaddr = 0;
ws.psections->p_paddr = 0;
ws.psections->p_filesz = notesize;
ws.psections->p_memsz = 0;
ws.psections->p_flags = PF_R;
ws.psections->p_align = ELFROUNDSIZE;
/* Write the P-section headers followed by the PT_NOTE header */
error = coredump_write(cookie, UIO_SYSSPACE, psections, psectionssize);
if (error)
goto out;
#ifdef DIAGNOSTIC
if (coredump_offset(cookie) != notestart)
panic("coredump: offset %lld != notestart %lld",
(long long) coredump_offset(cookie),
(long long) notestart);
#endif
/* Write out the notes. */
for (nb = ns.ns_first; nb != NULL; nb = nb->nb_next) {
error = coredump_write(cookie, UIO_SYSSPACE, nb->nb_data,
nb->nb_next == NULL ? ns.ns_offset : sizeof nb->nb_data);
if (error)
goto out;
}
/* Finally, write the sections themselves. */
for (i = 0; i < npsections - 1; i++) {
if (psections[i].p_filesz == 0)
continue;
#ifdef DIAGNOSTIC
if (coredump_offset(cookie) != psections[i].p_offset)
panic("coredump: offset %lld != p_offset[%d] %lld",
(long long) coredump_offset(cookie), i,
(long long) psections[i].p_filesz);
#endif
error = coredump_write(cookie, UIO_USERSPACE,
(void *)(vaddr_t)psections[i].p_vaddr,
psections[i].p_filesz);
if (error)
goto out;
}
out:
if (psections)
kmem_free(psections, psectionssize);
while ((nb = ns.ns_first) != NULL) {
ns.ns_first = nb->nb_next;
kmem_free(nb, sizeof *nb);
}
return (error);
}
static int
ELFNAMEEND(coredump_getseghdrs)(struct uvm_coredump_state *us)
{
struct writesegs_state *ws = us->cookie;
Elf_Phdr phdr;
vsize_t size, realsize;
vaddr_t end;
int error;
/* Don't overrun if there are more sections */
if (ws->npsections == 0)
return ENOMEM;
ws->npsections--;
size = us->end - us->start;
realsize = us->realend - us->start;
end = us->realend;
/* Don't bother writing out trailing zeros */
while (realsize > 0) {
long buf[1024 / sizeof(long)];
size_t slen = realsize > sizeof(buf) ? sizeof(buf) : realsize;
const long *ep;
int i;
end -= slen;
if ((error = copyin_proc(ws->p, (void *)end, buf, slen)) != 0)
return error;
ep = (const long *) &buf[slen / sizeof(buf[0])];
for (i = 0, ep--; buf <= ep; ep--, i++) {
if (*ep)
break;
}
realsize -= i * sizeof(buf[0]);
if (i * sizeof(buf[0]) < slen)
break;
}
phdr.p_type = PT_LOAD;
phdr.p_offset = ws->secoff;
phdr.p_vaddr = us->start;
phdr.p_paddr = 0;
phdr.p_filesz = realsize;
phdr.p_memsz = size;
phdr.p_flags = 0;
if (us->prot & VM_PROT_READ)
phdr.p_flags |= PF_R;
if (us->prot & VM_PROT_WRITE)
phdr.p_flags |= PF_W;
if (us->prot & VM_PROT_EXECUTE)
phdr.p_flags |= PF_X;
phdr.p_align = PAGE_SIZE;
ws->secoff += phdr.p_filesz;
*ws->psections++ = phdr;
return (0);
}
static int
ELFNAMEEND(coredump_notes)(struct lwp *l, struct note_state *ns)
{
struct proc *p;
struct netbsd_elfcore_procinfo cpi;
int error;
struct lwp *l0;
sigset_t ss1, ss2;
p = l->l_proc;
/* First, write an elfcore_procinfo. */
cpi.cpi_version = NETBSD_ELFCORE_PROCINFO_VERSION;
cpi.cpi_cpisize = sizeof(cpi);
cpi.cpi_signo = p->p_sigctx.ps_signo;
cpi.cpi_sigcode = p->p_sigctx.ps_code;
cpi.cpi_siglwp = p->p_sigctx.ps_lwp;
/*
* XXX This should be per-LWP.
*/
ss1 = p->p_sigpend.sp_set;
sigemptyset(&ss2);
LIST_FOREACH(l0, &p->p_lwps, l_sibling) {
sigplusset(&l0->l_sigpend.sp_set, &ss1);
sigplusset(&l0->l_sigmask, &ss2);
}
memcpy(&cpi.cpi_sigpend, &ss1, sizeof(cpi.cpi_sigpend));
memcpy(&cpi.cpi_sigmask, &ss2, sizeof(cpi.cpi_sigmask));
memcpy(&cpi.cpi_sigignore, &p->p_sigctx.ps_sigignore,
sizeof(cpi.cpi_sigignore));
memcpy(&cpi.cpi_sigcatch, &p->p_sigctx.ps_sigcatch,
sizeof(cpi.cpi_sigcatch));
cpi.cpi_pid = p->p_pid;
mutex_enter(proc_lock);
cpi.cpi_ppid = p->p_pptr->p_pid;
cpi.cpi_pgrp = p->p_pgid;
cpi.cpi_sid = p->p_session->s_sid;
mutex_exit(proc_lock);
cpi.cpi_ruid = kauth_cred_getuid(l->l_cred);
cpi.cpi_euid = kauth_cred_geteuid(l->l_cred);
cpi.cpi_svuid = kauth_cred_getsvuid(l->l_cred);
cpi.cpi_rgid = kauth_cred_getgid(l->l_cred);
cpi.cpi_egid = kauth_cred_getegid(l->l_cred);
cpi.cpi_svgid = kauth_cred_getsvgid(l->l_cred);
cpi.cpi_nlwps = p->p_nlwps;
(void)strncpy(cpi.cpi_name, p->p_comm, sizeof(cpi.cpi_name));
cpi.cpi_name[sizeof(cpi.cpi_name) - 1] = '\0';
ELFNAMEEND(coredump_savenote)(ns, ELF_NOTE_NETBSD_CORE_PROCINFO,
ELF_NOTE_NETBSD_CORE_NAME, &cpi, sizeof(cpi));
/* XXX Add hook for machdep per-proc notes. */
/*
* Now write the register info for the thread that caused the
* coredump.
*/
error = ELFNAMEEND(coredump_note)(l, ns);
if (error)
return (error);
/*
* Now, for each LWP, write the register info and any other
* per-LWP notes.
* Lock in case this is a gcore requested dump.
*/
mutex_enter(p->p_lock);
LIST_FOREACH(l0, &p->p_lwps, l_sibling) {
if (l0 == l) /* we've taken care of this thread */
continue;
error = ELFNAMEEND(coredump_note)(l0, ns);
if (error)
break;
}
mutex_exit(p->p_lock);
return error;
}
static int
ELFNAMEEND(coredump_note)(struct lwp *l, struct note_state *ns)
{
int error;
char name[64];
elf_reg intreg;
#ifdef PT_GETFPREGS
elf_fpreg freg;
size_t freglen;
#endif
snprintf(name, sizeof(name), "%s@%d",
ELF_NOTE_NETBSD_CORE_NAME, l->l_lid);
error = elf_process_read_regs(l, &intreg);
if (error)
return (error);
ELFNAMEEND(coredump_savenote)(ns, PT_GETREGS, name, &intreg,
sizeof(intreg));
#ifdef PT_GETFPREGS
freglen = sizeof(freg);
error = elf_process_read_fpregs(l, &freg, &freglen);
if (error)
return (error);
ELFNAMEEND(coredump_savenote)(ns, PT_GETFPREGS, name, &freg, freglen);
#endif
/* XXX Add hook for machdep per-LWP notes. */
return (0);
}
static void
save_note_bytes(struct note_state *ns, const void *data, size_t len)
{
struct note_buf *nb = ns->ns_last;
size_t copylen;
unsigned char *wp;
/*
* Just copy the data into a buffer list.
* All but the last buffer is full.
*/
for (;;) {
copylen = min(len, sizeof nb->nb_data - ns->ns_offset);
wp = nb->nb_data + ns->ns_offset;
memcpy(wp, data, copylen);
if (copylen == len)
break;
nb->nb_next = kmem_alloc(sizeof *nb->nb_next, KM_SLEEP);
nb = nb->nb_next;
ns->ns_last = nb;
ns->ns_count++;
ns->ns_offset = 0;
len -= copylen;
data = (const unsigned char *)data + copylen;
}
while (copylen & (ELFROUNDSIZE - 1))
wp[copylen++] = 0;
ns->ns_offset += copylen;
}
void
ELFNAMEEND(coredump_savenote)(struct note_state *ns, unsigned int type,
const char *name, void *data, size_t data_len)
{
Elf_Nhdr nhdr;
nhdr.n_namesz = strlen(name) + 1;
nhdr.n_descsz = data_len;
nhdr.n_type = type;
save_note_bytes(ns, &nhdr, sizeof (nhdr));
save_note_bytes(ns, name, nhdr.n_namesz);
save_note_bytes(ns, data, data_len);
}
#else /* COREDUMP */
int
ELFNAMEEND(coredump)(struct lwp *l, void *cookie)
{
return ENOSYS;
}
#endif /* COREDUMP */