elf.c revision d2a70789f056fc6c9ce3ab047b52126d80b0e3da
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright (c) 2013, Joyent, Inc. All rights reserved.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/thread.h>
#include <sys/sysmacros.h>
#include <sys/signal.h>
#include <sys/cred.h>
#include <sys/user.h>
#include <sys/errno.h>
#include <sys/vnode.h>
#include <sys/mman.h>
#include <sys/kmem.h>
#include <sys/proc.h>
#include <sys/pathname.h>
#include <sys/policy.h>
#include <sys/cmn_err.h>
#include <sys/systm.h>
#include <sys/elf.h>
#include <sys/vmsystm.h>
#include <sys/debug.h>
#include <sys/auxv.h>
#include <sys/exec.h>
#include <sys/prsystm.h>
#include <vm/as.h>
#include <vm/rm.h>
#include <vm/seg.h>
#include <vm/seg_vn.h>
#include <sys/modctl.h>
#include <sys/systeminfo.h>
#include <sys/vmparam.h>
#include <sys/machelf.h>
#include <sys/shm_impl.h>
#include <sys/archsystm.h>
#include <sys/fasttrap.h>
#include <sys/brand.h>
#include "elf_impl.h"
#include <sys/sdt.h>
#include <sys/siginfo.h>
#include <sys/random.h>
extern int at_flags;
extern volatile size_t aslr_max_brk_skew;
#define ORIGIN_STR "ORIGIN"
#define ORIGIN_STR_SIZE 6
static int getelfhead(vnode_t *, cred_t *, Ehdr *, int *, int *, int *);
static int getelfphdr(vnode_t *, cred_t *, const Ehdr *, int, caddr_t *,
ssize_t *);
static int getelfshdr(vnode_t *, cred_t *, const Ehdr *, int, int, caddr_t *,
ssize_t *, caddr_t *, ssize_t *);
static size_t elfsize(Ehdr *, int, caddr_t, uintptr_t *);
static int mapelfexec(vnode_t *, Ehdr *, int, caddr_t,
Phdr **, Phdr **, Phdr **, Phdr **, Phdr *,
caddr_t *, caddr_t *, intptr_t *, intptr_t *, size_t, long *, size_t *);
typedef enum {
STR_CTF,
STR_SYMTAB,
STR_DYNSYM,
STR_STRTAB,
STR_DYNSTR,
STR_SHSTRTAB,
STR_NUM
} shstrtype_t;
static const char *shstrtab_data[] = {
".SUNW_ctf",
".symtab",
".dynsym",
".strtab",
".dynstr",
".shstrtab"
};
typedef struct shstrtab {
int sst_ndx[STR_NUM];
int sst_cur;
} shstrtab_t;
static void
shstrtab_init(shstrtab_t *s)
{
bzero(&s->sst_ndx, sizeof (s->sst_ndx));
s->sst_cur = 1;
}
static int
shstrtab_ndx(shstrtab_t *s, shstrtype_t type)
{
int ret;
if ((ret = s->sst_ndx[type]) != 0)
return (ret);
ret = s->sst_ndx[type] = s->sst_cur;
s->sst_cur += strlen(shstrtab_data[type]) + 1;
return (ret);
}
static size_t
shstrtab_size(const shstrtab_t *s)
{
return (s->sst_cur);
}
static void
shstrtab_dump(const shstrtab_t *s, char *buf)
{
int i, ndx;
*buf = '\0';
for (i = 0; i < STR_NUM; i++) {
if ((ndx = s->sst_ndx[i]) != 0)
(void) strcpy(buf + ndx, shstrtab_data[i]);
}
}
static int
dtrace_safe_phdr(Phdr *phdrp, struct uarg *args, uintptr_t base)
{
ASSERT(phdrp->p_type == PT_SUNWDTRACE);
/*
* See the comment in fasttrap.h for information on how to safely
* update this program header.
*/
if (phdrp->p_memsz < PT_SUNWDTRACE_SIZE ||
(phdrp->p_flags & (PF_R | PF_W | PF_X)) != (PF_R | PF_W | PF_X))
return (-1);
args->thrptr = phdrp->p_vaddr + base;
return (0);
}
static int
handle_secflag_dt(proc_t *p, uint_t dt, uint_t val)
{
uint_t flag;
switch (dt) {
case DT_SUNW_ASLR:
flag = PROC_SEC_ASLR;
break;
default:
return (EINVAL);
}
if (val == 0) {
if (secflag_isset(p->p_secflags.psf_lower, flag))
return (EPERM);
if ((secpolicy_psecflags(CRED(), p, p) != 0) &&
secflag_isset(p->p_secflags.psf_inherit, flag))
return (EPERM);
secflag_clear(&p->p_secflags.psf_effective, flag);
} else {
if (!secflag_isset(p->p_secflags.psf_upper, flag))
return (EPERM);
if ((secpolicy_psecflags(CRED(), p, p) != 0) &&
!secflag_isset(p->p_secflags.psf_inherit, flag))
return (EPERM);
secflag_set(&p->p_secflags.psf_effective, flag);
}
return (0);
}
/*
* Map in the executable pointed to by vp. Returns 0 on success.
*/
int
mapexec_brand(vnode_t *vp, uarg_t *args, Ehdr *ehdr, Addr *uphdr_vaddr,
intptr_t *voffset, caddr_t exec_file, int *interp, caddr_t *bssbase,
caddr_t *brkbase, size_t *brksize, uintptr_t *lddatap)
{
size_t len;
struct vattr vat;
caddr_t phdrbase = NULL;
ssize_t phdrsize;
int nshdrs, shstrndx, nphdrs;
int error = 0;
Phdr *uphdr = NULL;
Phdr *junk = NULL;
Phdr *dynphdr = NULL;
Phdr *dtrphdr = NULL;
uintptr_t lddata;
long execsz;
intptr_t minaddr;
if (lddatap != NULL)
*lddatap = NULL;
if (error = execpermissions(vp, &vat, args)) {
uprintf("%s: Cannot execute %s\n", exec_file, args->pathname);
return (error);
}
if ((error = getelfhead(vp, CRED(), ehdr, &nshdrs, &shstrndx,
&nphdrs)) != 0 ||
(error = getelfphdr(vp, CRED(), ehdr, nphdrs, &phdrbase,
&phdrsize)) != 0) {
uprintf("%s: Cannot read %s\n", exec_file, args->pathname);
return (error);
}
if ((len = elfsize(ehdr, nphdrs, phdrbase, &lddata)) == 0) {
uprintf("%s: Nothing to load in %s", exec_file, args->pathname);
kmem_free(phdrbase, phdrsize);
return (ENOEXEC);
}
if (lddatap != NULL)
*lddatap = lddata;
if (error = mapelfexec(vp, ehdr, nphdrs, phdrbase, &uphdr, &dynphdr,
&junk, &dtrphdr, NULL, bssbase, brkbase, voffset, &minaddr,
len, &execsz, brksize)) {
uprintf("%s: Cannot map %s\n", exec_file, args->pathname);
kmem_free(phdrbase, phdrsize);
return (error);
}
/*
* Inform our caller if the executable needs an interpreter.
*/
*interp = (dynphdr == NULL) ? 0 : 1;
/*
* If this is a statically linked executable, voffset should indicate
* the address of the executable itself (it normally holds the address
* of the interpreter).
*/
if (ehdr->e_type == ET_EXEC && *interp == 0)
*voffset = minaddr;
if (uphdr != NULL) {
*uphdr_vaddr = uphdr->p_vaddr;
} else {
*uphdr_vaddr = (Addr)-1;
}
kmem_free(phdrbase, phdrsize);
return (error);
}
/*ARGSUSED*/
int
elfexec(vnode_t *vp, execa_t *uap, uarg_t *args, intpdata_t *idatap,
int level, long *execsz, int setid, caddr_t exec_file, cred_t *cred,
int brand_action)
{
caddr_t phdrbase = NULL;
caddr_t bssbase = 0;
caddr_t brkbase = 0;
size_t brksize = 0;
ssize_t dlnsize;
aux_entry_t *aux;
int error;
ssize_t resid;
int fd = -1;
intptr_t voffset;
Phdr *intphdr = NULL;
Phdr *dynamicphdr = NULL;
Phdr *stphdr = NULL;
Phdr *uphdr = NULL;
Phdr *junk = NULL;
size_t len;
ssize_t phdrsize;
int postfixsize = 0;
int i, hsize;
Phdr *phdrp;
Phdr *dataphdrp = NULL;
Phdr *dtrphdr;
Phdr *capphdr = NULL;
Cap *cap = NULL;
ssize_t capsize;
Dyn *dyn = NULL;
int hasu = 0;
int hasauxv = 0;
int hasintp = 0;
int branded = 0;
struct proc *p = ttoproc(curthread);
struct user *up = PTOU(p);
struct bigwad {
Ehdr ehdr;
aux_entry_t elfargs[__KERN_NAUXV_IMPL];
char dl_name[MAXPATHLEN];
char pathbuf[MAXPATHLEN];
struct vattr vattr;
struct execenv exenv;
} *bigwad; /* kmem_alloc this behemoth so we don't blow stack */
Ehdr *ehdrp;
int nshdrs, shstrndx, nphdrs;
char *dlnp;
char *pathbufp;
rlim64_t limit;
rlim64_t roundlimit;
ASSERT(p->p_model == DATAMODEL_ILP32 || p->p_model == DATAMODEL_LP64);
bigwad = kmem_alloc(sizeof (struct bigwad), KM_SLEEP);
ehdrp = &bigwad->ehdr;
dlnp = bigwad->dl_name;
pathbufp = bigwad->pathbuf;
/*
* Obtain ELF and program header information.
*/
if ((error = getelfhead(vp, CRED(), ehdrp, &nshdrs, &shstrndx,
&nphdrs)) != 0 ||
(error = getelfphdr(vp, CRED(), ehdrp, nphdrs, &phdrbase,
&phdrsize)) != 0)
goto out;
/*
* Prevent executing an ELF file that has no entry point.
*/
if (ehdrp->e_entry == 0) {
uprintf("%s: Bad entry point\n", exec_file);
goto bad;
}
/*
* Put data model that we're exec-ing to into the args passed to
* exec_args(), so it will know what it is copying to on new stack.
* Now that we know whether we are exec-ing a 32-bit or 64-bit
* executable, we can set execsz with the appropriate NCARGS.
*/
#ifdef _LP64
if (ehdrp->e_ident[EI_CLASS] == ELFCLASS32) {
args->to_model = DATAMODEL_ILP32;
*execsz = btopr(SINCR) + btopr(SSIZE) + btopr(NCARGS32-1);
} else {
args->to_model = DATAMODEL_LP64;
args->stk_prot &= ~PROT_EXEC;
#if defined(__i386) || defined(__amd64)
args->dat_prot &= ~PROT_EXEC;
#endif
*execsz = btopr(SINCR) + btopr(SSIZE) + btopr(NCARGS64-1);
}
#else /* _LP64 */
args->to_model = DATAMODEL_ILP32;
*execsz = btopr(SINCR) + btopr(SSIZE) + btopr(NCARGS-1);
#endif /* _LP64 */
/*
* We delay invoking the brand callback until we've figured out
* what kind of elf binary we're trying to run, 32-bit or 64-bit.
* We do this because now the brand library can just check
* args->to_model to see if the target is 32-bit or 64-bit without
* having do duplicate all the code above.
*
* The level checks associated with brand handling below are used to
* prevent a loop since the brand elfexec function typically comes back
* through this function. We must check <= here since the nested
* handling in the #! interpreter code will increment the level before
* calling gexec to run the final elfexec interpreter.
*/
if ((level <= INTP_MAXDEPTH) &&
(brand_action != EBA_NATIVE) && (PROC_IS_BRANDED(p))) {
error = BROP(p)->b_elfexec(vp, uap, args,
idatap, level + 1, execsz, setid, exec_file, cred,
brand_action);
goto out;
}
/*
* Determine aux size now so that stack can be built
* in one shot (except actual copyout of aux image),
* determine any non-default stack protections,
* and still have this code be machine independent.
*/
hsize = ehdrp->e_phentsize;
phdrp = (Phdr *)phdrbase;
for (i = nphdrs; i > 0; i--) {
switch (phdrp->p_type) {
case PT_INTERP:
hasauxv = hasintp = 1;
break;
case PT_PHDR:
hasu = 1;
break;
case PT_SUNWSTACK:
args->stk_prot = PROT_USER;
if (phdrp->p_flags & PF_R)
args->stk_prot |= PROT_READ;
if (phdrp->p_flags & PF_W)
args->stk_prot |= PROT_WRITE;
if (phdrp->p_flags & PF_X)
args->stk_prot |= PROT_EXEC;
break;
case PT_LOAD:
dataphdrp = phdrp;
break;
case PT_SUNWCAP:
capphdr = phdrp;
break;
case PT_DYNAMIC:
dynamicphdr = phdrp;
break;
}
phdrp = (Phdr *)((caddr_t)phdrp + hsize);
}
if (ehdrp->e_type != ET_EXEC) {
dataphdrp = NULL;
hasauxv = 1;
}
/* Copy BSS permissions to args->dat_prot */
if (dataphdrp != NULL) {
args->dat_prot = PROT_USER;
if (dataphdrp->p_flags & PF_R)
args->dat_prot |= PROT_READ;
if (dataphdrp->p_flags & PF_W)
args->dat_prot |= PROT_WRITE;
if (dataphdrp->p_flags & PF_X)
args->dat_prot |= PROT_EXEC;
}
/*
* If a auxvector will be required - reserve the space for
* it now. This may be increased by exec_args if there are
* ISA-specific types (included in __KERN_NAUXV_IMPL).
*/
if (hasauxv) {
/*
* If a AUX vector is being built - the base AUX
* entries are:
*
* AT_BASE
* AT_FLAGS
* AT_PAGESZ
* AT_SUN_AUXFLAGS
* AT_SUN_HWCAP
* AT_SUN_HWCAP2
* AT_SUN_PLATFORM (added in stk_copyout)
* AT_SUN_EXECNAME (added in stk_copyout)
* AT_NULL
*
* total == 9
*/
if (hasintp && hasu) {
/*
* Has PT_INTERP & PT_PHDR - the auxvectors that
* will be built are:
*
* AT_PHDR
* AT_PHENT
* AT_PHNUM
* AT_ENTRY
* AT_LDDATA
*
* total = 5
*/
args->auxsize = (9 + 5) * sizeof (aux_entry_t);
} else if (hasintp) {
/*
* Has PT_INTERP but no PT_PHDR
*
* AT_EXECFD
* AT_LDDATA
*
* total = 2
*/
args->auxsize = (9 + 2) * sizeof (aux_entry_t);
} else {
args->auxsize = 9 * sizeof (aux_entry_t);
}
} else {
args->auxsize = 0;
}
/*
* If this binary is using an emulator, we need to add an
* AT_SUN_EMULATOR aux entry.
*/
if (args->emulator != NULL)
args->auxsize += sizeof (aux_entry_t);
if ((brand_action != EBA_NATIVE) && (PROC_IS_BRANDED(p))) {
branded = 1;
/*
* We will be adding 4 entries to the aux vectors. One for
* the the brandname and 3 for the brand specific aux vectors.
*/
args->auxsize += 4 * sizeof (aux_entry_t);
}
/* If the binary has an explicit ASLR flag, it must be honoured */
if ((dynamicphdr != NULL) &&
(dynamicphdr->p_filesz > 0)) {
Dyn *dp;
off_t i = 0;
#define DYN_STRIDE 100
for (i = 0; i < dynamicphdr->p_filesz;
i += sizeof (*dyn) * DYN_STRIDE) {
int ndyns = (dynamicphdr->p_filesz - i) / sizeof (*dyn);
size_t dynsize;
ndyns = MIN(DYN_STRIDE, ndyns);
dynsize = ndyns * sizeof (*dyn);
dyn = kmem_alloc(dynsize, KM_SLEEP);
if ((error = vn_rdwr(UIO_READ, vp, (caddr_t)dyn,
dynsize, (offset_t)(dynamicphdr->p_offset + i),
UIO_SYSSPACE, 0, (rlim64_t)0,
CRED(), &resid)) != 0) {
uprintf("%s: cannot read .dynamic section\n",
exec_file);
goto out;
}
for (dp = dyn; dp < (dyn + ndyns); dp++) {
if (dp->d_tag == DT_SUNW_ASLR) {
if ((error = handle_secflag_dt(p,
DT_SUNW_ASLR,
dp->d_un.d_val)) != 0) {
uprintf("%s: error setting "
"security-flag from "
"DT_SUNW_ASLR: %d\n",
exec_file, error);
goto out;
}
}
}
kmem_free(dyn, dynsize);
}
}
/* Hardware/Software capabilities */
if (capphdr != NULL &&
(capsize = capphdr->p_filesz) > 0 &&
capsize <= 16 * sizeof (*cap)) {
int ncaps = capsize / sizeof (*cap);
Cap *cp;
cap = kmem_alloc(capsize, KM_SLEEP);
if ((error = vn_rdwr(UIO_READ, vp, (caddr_t)cap,
capsize, (offset_t)capphdr->p_offset,
UIO_SYSSPACE, 0, (rlim64_t)0, CRED(), &resid)) != 0) {
uprintf("%s: Cannot read capabilities section\n",
exec_file);
goto out;
}
for (cp = cap; cp < cap + ncaps; cp++) {
if (cp->c_tag == CA_SUNW_SF_1 &&
(cp->c_un.c_val & SF1_SUNW_ADDR32)) {
if (args->to_model == DATAMODEL_LP64)
args->addr32 = 1;
break;
}
}
}
aux = bigwad->elfargs;
/*
* Move args to the user's stack.
* This can fill in the AT_SUN_PLATFORM and AT_SUN_EXECNAME aux entries.
*/
if ((error = exec_args(uap, args, idatap, (void **)&aux)) != 0) {
if (error == -1) {
error = ENOEXEC;
goto bad;
}
goto out;
}
/* we're single threaded after this point */
/*
* If this is an ET_DYN executable (shared object),
* determine its memory size so that mapelfexec() can load it.
*/
if (ehdrp->e_type == ET_DYN)
len = elfsize(ehdrp, nphdrs, phdrbase, NULL);
else
len = 0;
dtrphdr = NULL;
if ((error = mapelfexec(vp, ehdrp, nphdrs, phdrbase, &uphdr, &intphdr,
&stphdr, &dtrphdr, dataphdrp, &bssbase, &brkbase, &voffset, NULL,
len, execsz, &brksize)) != 0)
goto bad;
if (uphdr != NULL && intphdr == NULL)
goto bad;
if (dtrphdr != NULL && dtrace_safe_phdr(dtrphdr, args, voffset) != 0) {
uprintf("%s: Bad DTrace phdr in %s\n", exec_file, exec_file);
goto bad;
}
if (intphdr != NULL) {
size_t len;
uintptr_t lddata;
char *p;
struct vnode *nvp;
dlnsize = intphdr->p_filesz;
if (dlnsize > MAXPATHLEN || dlnsize <= 0)
goto bad;
/*
* Read in "interpreter" pathname.
*/
if ((error = vn_rdwr(UIO_READ, vp, dlnp, intphdr->p_filesz,
(offset_t)intphdr->p_offset, UIO_SYSSPACE, 0, (rlim64_t)0,
CRED(), &resid)) != 0) {
uprintf("%s: Cannot obtain interpreter pathname\n",
exec_file);
goto bad;
}
if (resid != 0 || dlnp[dlnsize - 1] != '\0')
goto bad;
/*
* Search for '$ORIGIN' token in interpreter path.
* If found, expand it.
*/
for (p = dlnp; p = strchr(p, '$'); ) {
uint_t len, curlen;
char *_ptr;
if (strncmp(++p, ORIGIN_STR, ORIGIN_STR_SIZE))
continue;
/*
* We don't support $ORIGIN on setid programs to close
* a potential attack vector.
*/
if ((setid & EXECSETID_SETID) != 0) {
error = ENOEXEC;
goto bad;
}
curlen = 0;
len = p - dlnp - 1;
if (len) {
bcopy(dlnp, pathbufp, len);
curlen += len;
}
if (_ptr = strrchr(args->pathname, '/')) {
len = _ptr - args->pathname;
if ((curlen + len) > MAXPATHLEN)
break;
bcopy(args->pathname, &pathbufp[curlen], len);
curlen += len;
} else {
/*
* executable is a basename found in the
* current directory. So - just substitue
* '.' for ORIGIN.
*/
pathbufp[curlen] = '.';
curlen++;
}
p += ORIGIN_STR_SIZE;
len = strlen(p);
if ((curlen + len) > MAXPATHLEN)
break;
bcopy(p, &pathbufp[curlen], len);
curlen += len;
pathbufp[curlen++] = '\0';
bcopy(pathbufp, dlnp, curlen);
}
/*
* /usr/lib/ld.so.1 is known to be a symlink to /lib/ld.so.1
* (and /usr/lib/64/ld.so.1 is a symlink to /lib/64/ld.so.1).
* Just in case /usr is not mounted, change it now.
*/
if (strcmp(dlnp, USR_LIB_RTLD) == 0)
dlnp += 4;
error = lookupname(dlnp, UIO_SYSSPACE, FOLLOW, NULLVPP, &nvp);
if (error && dlnp != bigwad->dl_name) {
/* new kernel, old user-level */
error = lookupname(dlnp -= 4, UIO_SYSSPACE, FOLLOW,
NULLVPP, &nvp);
}
if (error) {
uprintf("%s: Cannot find %s\n", exec_file, dlnp);
goto bad;
}
/*
* Setup the "aux" vector.
*/
if (uphdr) {
if (ehdrp->e_type == ET_DYN) {
/* don't use the first page */
bigwad->exenv.ex_brkbase = (caddr_t)PAGESIZE;
bigwad->exenv.ex_bssbase = (caddr_t)PAGESIZE;
} else {
bigwad->exenv.ex_bssbase = bssbase;
bigwad->exenv.ex_brkbase = brkbase;
}
bigwad->exenv.ex_brksize = brksize;
bigwad->exenv.ex_magic = elfmagic;
bigwad->exenv.ex_vp = vp;
setexecenv(&bigwad->exenv);
ADDAUX(aux, AT_PHDR, uphdr->p_vaddr + voffset)
ADDAUX(aux, AT_PHENT, ehdrp->e_phentsize)
ADDAUX(aux, AT_PHNUM, nphdrs)
ADDAUX(aux, AT_ENTRY, ehdrp->e_entry + voffset)
} else {
if ((error = execopen(&vp, &fd)) != 0) {
VN_RELE(nvp);
goto bad;
}
ADDAUX(aux, AT_EXECFD, fd)
}
if ((error = execpermissions(nvp, &bigwad->vattr, args)) != 0) {
VN_RELE(nvp);
uprintf("%s: Cannot execute %s\n", exec_file, dlnp);
goto bad;
}
/*
* Now obtain the ELF header along with the entire program
* header contained in "nvp".
*/
kmem_free(phdrbase, phdrsize);
phdrbase = NULL;
if ((error = getelfhead(nvp, CRED(), ehdrp, &nshdrs,
&shstrndx, &nphdrs)) != 0 ||
(error = getelfphdr(nvp, CRED(), ehdrp, nphdrs, &phdrbase,
&phdrsize)) != 0) {
VN_RELE(nvp);
uprintf("%s: Cannot read %s\n", exec_file, dlnp);
goto bad;
}
/*
* Determine memory size of the "interpreter's" loadable
* sections. This size is then used to obtain the virtual
* address of a hole, in the user's address space, large
* enough to map the "interpreter".
*/
if ((len = elfsize(ehdrp, nphdrs, phdrbase, &lddata)) == 0) {
VN_RELE(nvp);
uprintf("%s: Nothing to load in %s\n", exec_file, dlnp);
goto bad;
}
dtrphdr = NULL;
error = mapelfexec(nvp, ehdrp, nphdrs, phdrbase, &junk, &junk,
&junk, &dtrphdr, NULL, NULL, NULL, &voffset, NULL, len,
execsz, NULL);
if (error || junk != NULL) {
VN_RELE(nvp);
uprintf("%s: Cannot map %s\n", exec_file, dlnp);
goto bad;
}
/*
* We use the DTrace program header to initialize the
* architecture-specific user per-LWP location. The dtrace
* fasttrap provider requires ready access to per-LWP scratch
* space. We assume that there is only one such program header
* in the interpreter.
*/
if (dtrphdr != NULL &&
dtrace_safe_phdr(dtrphdr, args, voffset) != 0) {
VN_RELE(nvp);
uprintf("%s: Bad DTrace phdr in %s\n", exec_file, dlnp);
goto bad;
}
VN_RELE(nvp);
ADDAUX(aux, AT_SUN_LDDATA, voffset + lddata)
}
if (hasauxv) {
int auxf = AF_SUN_HWCAPVERIFY;
/*
* Note: AT_SUN_PLATFORM and AT_SUN_EXECNAME were filled in via
* exec_args()
*/
ADDAUX(aux, AT_BASE, voffset)
ADDAUX(aux, AT_FLAGS, at_flags)
ADDAUX(aux, AT_PAGESZ, PAGESIZE)
/*
* Linker flags. (security)
* p_flag not yet set at this time.
* We rely on gexec() to provide us with the information.
* If the application is set-uid but this is not reflected
* in a mismatch between real/effective uids/gids, then
* don't treat this as a set-uid exec. So we care about
* the EXECSETID_UGIDS flag but not the ...SETID flag.
*/
if ((setid &= ~EXECSETID_SETID) != 0)
auxf |= AF_SUN_SETUGID;
/*
* If we're running a native process from within a branded
* zone under pfexec then we clear the AF_SUN_SETUGID flag so
* that the native ld.so.1 is able to link with the native
* libraries instead of using the brand libraries that are
* installed in the zone. We only do this for processes
* which we trust because we see they are already running
* under pfexec (where uid != euid). This prevents a
* malicious user within the zone from crafting a wrapper to
* run native suid commands with unsecure libraries interposed.
*/
if ((brand_action == EBA_NATIVE) && (PROC_IS_BRANDED(p) &&
(setid &= ~EXECSETID_SETID) != 0))
auxf &= ~AF_SUN_SETUGID;
/*
* Record the user addr of the auxflags aux vector entry
* since brands may optionally want to manipulate this field.
*/
args->auxp_auxflags =
(char *)((char *)args->stackend +
((char *)&aux->a_type -
(char *)bigwad->elfargs));
ADDAUX(aux, AT_SUN_AUXFLAGS, auxf);
/*
* Hardware capability flag word (performance hints)
* Used for choosing faster library routines.
* (Potentially different between 32-bit and 64-bit ABIs)
*/
#if defined(_LP64)
if (args->to_model == DATAMODEL_NATIVE) {
ADDAUX(aux, AT_SUN_HWCAP, auxv_hwcap)
ADDAUX(aux, AT_SUN_HWCAP2, auxv_hwcap_2)
} else {
ADDAUX(aux, AT_SUN_HWCAP, auxv_hwcap32)
ADDAUX(aux, AT_SUN_HWCAP2, auxv_hwcap32_2)
}
#else
ADDAUX(aux, AT_SUN_HWCAP, auxv_hwcap)
ADDAUX(aux, AT_SUN_HWCAP2, auxv_hwcap_2)
#endif
if (branded) {
/*
* Reserve space for the brand-private aux vectors,
* and record the user addr of that space.
*/
args->auxp_brand =
(char *)((char *)args->stackend +
((char *)&aux->a_type -
(char *)bigwad->elfargs));
ADDAUX(aux, AT_SUN_BRAND_AUX1, 0)
ADDAUX(aux, AT_SUN_BRAND_AUX2, 0)
ADDAUX(aux, AT_SUN_BRAND_AUX3, 0)
}
ADDAUX(aux, AT_NULL, 0)
postfixsize = (char *)aux - (char *)bigwad->elfargs;
/*
* We make assumptions above when we determine how many aux
* vector entries we will be adding. However, if we have an
* invalid elf file, it is possible that mapelfexec might
* behave differently (but not return an error), in which case
* the number of aux entries we actually add will be different.
* We detect that now and error out.
*/
if (postfixsize != args->auxsize) {
DTRACE_PROBE2(elfexec_badaux, int, postfixsize,
int, args->auxsize);
goto bad;
}
ASSERT(postfixsize <= __KERN_NAUXV_IMPL * sizeof (aux_entry_t));
}
/*
* For the 64-bit kernel, the limit is big enough that rounding it up
* to a page can overflow the 64-bit limit, so we check for btopr()
* overflowing here by comparing it with the unrounded limit in pages.
* If it hasn't overflowed, compare the exec size with the rounded up
* limit in pages. Otherwise, just compare with the unrounded limit.
*/
limit = btop(p->p_vmem_ctl);
roundlimit = btopr(p->p_vmem_ctl);
if ((roundlimit > limit && *execsz > roundlimit) ||
(roundlimit < limit && *execsz > limit)) {
mutex_enter(&p->p_lock);
(void) rctl_action(rctlproc_legacy[RLIMIT_VMEM], p->p_rctls, p,
RCA_SAFE);
mutex_exit(&p->p_lock);
error = ENOMEM;
goto bad;
}
bzero(up->u_auxv, sizeof (up->u_auxv));
if (postfixsize) {
int num_auxv;
/*
* Copy the aux vector to the user stack.
*/
error = execpoststack(args, bigwad->elfargs, postfixsize);
if (error)
goto bad;
/*
* Copy auxv to the process's user structure for use by /proc.
* If this is a branded process, the brand's exec routine will
* copy it's private entries to the user structure later. It
* relies on the fact that the blank entries are at the end.
*/
num_auxv = postfixsize / sizeof (aux_entry_t);
ASSERT(num_auxv <= sizeof (up->u_auxv) / sizeof (auxv_t));
aux = bigwad->elfargs;
for (i = 0; i < num_auxv; i++) {
up->u_auxv[i].a_type = aux[i].a_type;
up->u_auxv[i].a_un.a_val = (aux_val_t)aux[i].a_un.a_val;
}
}
/*
* Pass back the starting address so we can set the program counter.
*/
args->entry = (uintptr_t)(ehdrp->e_entry + voffset);
if (!uphdr) {
if (ehdrp->e_type == ET_DYN) {
/*
* If we are executing a shared library which doesn't
* have a interpreter (probably ld.so.1) then
* we don't set the brkbase now. Instead we
* delay it's setting until the first call
* via grow.c::brk(). This permits ld.so.1 to
* initialize brkbase to the tail of the executable it
* loads (which is where it needs to be).
*/
bigwad->exenv.ex_brkbase = (caddr_t)0;
bigwad->exenv.ex_bssbase = (caddr_t)0;
bigwad->exenv.ex_brksize = 0;
} else {
bigwad->exenv.ex_brkbase = brkbase;
bigwad->exenv.ex_bssbase = bssbase;
bigwad->exenv.ex_brksize = brksize;
}
bigwad->exenv.ex_magic = elfmagic;
bigwad->exenv.ex_vp = vp;
setexecenv(&bigwad->exenv);
}
ASSERT(error == 0);
goto out;
bad:
if (fd != -1) /* did we open the a.out yet */
(void) execclose(fd);
psignal(p, SIGKILL);
if (error == 0)
error = ENOEXEC;
out:
if (phdrbase != NULL)
kmem_free(phdrbase, phdrsize);
if (cap != NULL)
kmem_free(cap, capsize);
kmem_free(bigwad, sizeof (struct bigwad));
return (error);
}
/*
* Compute the memory size requirement for the ELF file.
*/
static size_t
elfsize(Ehdr *ehdrp, int nphdrs, caddr_t phdrbase, uintptr_t *lddata)
{
size_t len;
Phdr *phdrp = (Phdr *)phdrbase;
int hsize = ehdrp->e_phentsize;
int first = 1;
int dfirst = 1; /* first data segment */
uintptr_t loaddr = 0;
uintptr_t hiaddr = 0;
uintptr_t lo, hi;
int i;
for (i = nphdrs; i > 0; i--) {
if (phdrp->p_type == PT_LOAD) {
lo = phdrp->p_vaddr;
hi = lo + phdrp->p_memsz;
if (first) {
loaddr = lo;
hiaddr = hi;
first = 0;
} else {
if (loaddr > lo)
loaddr = lo;
if (hiaddr < hi)
hiaddr = hi;
}
/*
* save the address of the first data segment
* of a object - used for the AT_SUNW_LDDATA
* aux entry.
*/
if ((lddata != NULL) && dfirst &&
(phdrp->p_flags & PF_W)) {
*lddata = lo;
dfirst = 0;
}
}
phdrp = (Phdr *)((caddr_t)phdrp + hsize);
}
len = hiaddr - (loaddr & PAGEMASK);
len = roundup(len, PAGESIZE);
return (len);
}
/*
* Read in the ELF header and program header table.
* SUSV3 requires:
* ENOEXEC File format is not recognized
* EINVAL Format recognized but execution not supported
*/
static int
getelfhead(vnode_t *vp, cred_t *credp, Ehdr *ehdr, int *nshdrs, int *shstrndx,
int *nphdrs)
{
int error;
ssize_t resid;
/*
* We got here by the first two bytes in ident,
* now read the entire ELF header.
*/
if ((error = vn_rdwr(UIO_READ, vp, (caddr_t)ehdr,
sizeof (Ehdr), (offset_t)0, UIO_SYSSPACE, 0,
(rlim64_t)0, credp, &resid)) != 0)
return (error);
/*
* Since a separate version is compiled for handling 32-bit and
* 64-bit ELF executables on a 64-bit kernel, the 64-bit version
* doesn't need to be able to deal with 32-bit ELF files.
*/
if (resid != 0 ||
ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
ehdr->e_ident[EI_MAG3] != ELFMAG3)
return (ENOEXEC);
if ((ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) ||
#if defined(_ILP32) || defined(_ELF32_COMPAT)
ehdr->e_ident[EI_CLASS] != ELFCLASS32 ||
#else
ehdr->e_ident[EI_CLASS] != ELFCLASS64 ||
#endif
!elfheadcheck(ehdr->e_ident[EI_DATA], ehdr->e_machine,
ehdr->e_flags))
return (EINVAL);
*nshdrs = ehdr->e_shnum;
*shstrndx = ehdr->e_shstrndx;
*nphdrs = ehdr->e_phnum;
/*
* If e_shnum, e_shstrndx, or e_phnum is its sentinel value, we need
* to read in the section header at index zero to acces the true
* values for those fields.
*/
if ((*nshdrs == 0 && ehdr->e_shoff != 0) ||
*shstrndx == SHN_XINDEX || *nphdrs == PN_XNUM) {
Shdr shdr;
if (ehdr->e_shoff == 0)
return (EINVAL);
if ((error = vn_rdwr(UIO_READ, vp, (caddr_t)&shdr,
sizeof (shdr), (offset_t)ehdr->e_shoff, UIO_SYSSPACE, 0,
(rlim64_t)0, credp, &resid)) != 0)
return (error);
if (*nshdrs == 0)
*nshdrs = shdr.sh_size;
if (*shstrndx == SHN_XINDEX)
*shstrndx = shdr.sh_link;
if (*nphdrs == PN_XNUM && shdr.sh_info != 0)
*nphdrs = shdr.sh_info;
}
return (0);
}
#ifdef _ELF32_COMPAT
extern size_t elf_nphdr_max;
#else
size_t elf_nphdr_max = 1000;
#endif
static int
getelfphdr(vnode_t *vp, cred_t *credp, const Ehdr *ehdr, int nphdrs,
caddr_t *phbasep, ssize_t *phsizep)
{
ssize_t resid, minsize;
int err;
/*
* Since we're going to be using e_phentsize to iterate down the
* array of program headers, it must be 8-byte aligned or else
* a we might cause a misaligned access. We use all members through
* p_flags on 32-bit ELF files and p_memsz on 64-bit ELF files so
* e_phentsize must be at least large enough to include those
* members.
*/
#if !defined(_LP64) || defined(_ELF32_COMPAT)
minsize = offsetof(Phdr, p_flags) + sizeof (((Phdr *)NULL)->p_flags);
#else
minsize = offsetof(Phdr, p_memsz) + sizeof (((Phdr *)NULL)->p_memsz);
#endif
if (ehdr->e_phentsize < minsize || (ehdr->e_phentsize & 3))
return (EINVAL);
*phsizep = nphdrs * ehdr->e_phentsize;
if (*phsizep > sizeof (Phdr) * elf_nphdr_max) {
if ((*phbasep = kmem_alloc(*phsizep, KM_NOSLEEP)) == NULL)
return (ENOMEM);
} else {
*phbasep = kmem_alloc(*phsizep, KM_SLEEP);
}
if ((err = vn_rdwr(UIO_READ, vp, *phbasep, *phsizep,
(offset_t)ehdr->e_phoff, UIO_SYSSPACE, 0, (rlim64_t)0,
credp, &resid)) != 0) {
kmem_free(*phbasep, *phsizep);
*phbasep = NULL;
return (err);
}
return (0);
}
#ifdef _ELF32_COMPAT
extern size_t elf_nshdr_max;
extern size_t elf_shstrtab_max;
#else
size_t elf_nshdr_max = 10000;
size_t elf_shstrtab_max = 100 * 1024;
#endif
static int
getelfshdr(vnode_t *vp, cred_t *credp, const Ehdr *ehdr,
int nshdrs, int shstrndx, caddr_t *shbasep, ssize_t *shsizep,
char **shstrbasep, ssize_t *shstrsizep)
{
ssize_t resid, minsize;
int err;
Shdr *shdr;
/*
* Since we're going to be using e_shentsize to iterate down the
* array of section headers, it must be 8-byte aligned or else
* a we might cause a misaligned access. We use all members through
* sh_entsize (on both 32- and 64-bit ELF files) so e_shentsize
* must be at least large enough to include that member. The index
* of the string table section must also be valid.
*/
minsize = offsetof(Shdr, sh_entsize) + sizeof (shdr->sh_entsize);
if (ehdr->e_shentsize < minsize || (ehdr->e_shentsize & 3) ||
shstrndx >= nshdrs)
return (EINVAL);
*shsizep = nshdrs * ehdr->e_shentsize;
if (*shsizep > sizeof (Shdr) * elf_nshdr_max) {
if ((*shbasep = kmem_alloc(*shsizep, KM_NOSLEEP)) == NULL)
return (ENOMEM);
} else {
*shbasep = kmem_alloc(*shsizep, KM_SLEEP);
}
if ((err = vn_rdwr(UIO_READ, vp, *shbasep, *shsizep,
(offset_t)ehdr->e_shoff, UIO_SYSSPACE, 0, (rlim64_t)0,
credp, &resid)) != 0) {
kmem_free(*shbasep, *shsizep);
return (err);
}
/*
* Pull the section string table out of the vnode; fail if the size
* is zero.
*/
shdr = (Shdr *)(*shbasep + shstrndx * ehdr->e_shentsize);
if ((*shstrsizep = shdr->sh_size) == 0) {
kmem_free(*shbasep, *shsizep);
return (EINVAL);
}
if (*shstrsizep > elf_shstrtab_max) {
if ((*shstrbasep = kmem_alloc(*shstrsizep,
KM_NOSLEEP)) == NULL) {
kmem_free(*shbasep, *shsizep);
return (ENOMEM);
}
} else {
*shstrbasep = kmem_alloc(*shstrsizep, KM_SLEEP);
}
if ((err = vn_rdwr(UIO_READ, vp, *shstrbasep, *shstrsizep,
(offset_t)shdr->sh_offset, UIO_SYSSPACE, 0, (rlim64_t)0,
credp, &resid)) != 0) {
kmem_free(*shbasep, *shsizep);
kmem_free(*shstrbasep, *shstrsizep);
return (err);
}
/*
* Make sure the strtab is null-terminated to make sure we
* don't run off the end of the table.
*/
(*shstrbasep)[*shstrsizep - 1] = '\0';
return (0);
}
static int
mapelfexec(
vnode_t *vp,
Ehdr *ehdr,
int nphdrs,
caddr_t phdrbase,
Phdr **uphdr,
Phdr **intphdr,
Phdr **stphdr,
Phdr **dtphdr,
Phdr *dataphdrp,
caddr_t *bssbase,
caddr_t *brkbase,
intptr_t *voffset,
intptr_t *minaddr,
size_t len,
long *execsz,
size_t *brksize)
{
Phdr *phdr;
int i, prot, error;
caddr_t addr = NULL;
size_t zfodsz;
int ptload = 0;
int page;
off_t offset;
int hsize = ehdr->e_phentsize;
caddr_t mintmp = (caddr_t)-1;
extern int use_brk_lpg;
if (ehdr->e_type == ET_DYN) {
secflagset_t flags = 0;
/*
* Obtain the virtual address of a hole in the
* address space to map the "interpreter".
*/
if (secflag_enabled(curproc, PROC_SEC_ASLR))
flags |= _MAP_RANDOMIZE;
map_addr(&addr, len, (offset_t)0, 1, flags);
if (addr == NULL)
return (ENOMEM);
*voffset = (intptr_t)addr;
/*
* Calculate the minimum vaddr so it can be subtracted out.
* According to the ELF specification, since PT_LOAD sections
* must be sorted by increasing p_vaddr values, this is
* guaranteed to be the first PT_LOAD section.
*/
phdr = (Phdr *)phdrbase;
for (i = nphdrs; i > 0; i--) {
if (phdr->p_type == PT_LOAD) {
*voffset -= (uintptr_t)phdr->p_vaddr;
break;
}
phdr = (Phdr *)((caddr_t)phdr + hsize);
}
} else {
*voffset = 0;
}
phdr = (Phdr *)phdrbase;
for (i = nphdrs; i > 0; i--) {
switch (phdr->p_type) {
case PT_LOAD:
if ((*intphdr != NULL) && (*uphdr == NULL))
return (0);
ptload = 1;
prot = PROT_USER;
if (phdr->p_flags & PF_R)
prot |= PROT_READ;
if (phdr->p_flags & PF_W)
prot |= PROT_WRITE;
if (phdr->p_flags & PF_X)
prot |= PROT_EXEC;
addr = (caddr_t)((uintptr_t)phdr->p_vaddr + *voffset);
/*
* Keep track of the segment with the lowest starting
* address.
*/
if (addr < mintmp)
mintmp = addr;
zfodsz = (size_t)phdr->p_memsz - phdr->p_filesz;
offset = phdr->p_offset;
if (((uintptr_t)offset & PAGEOFFSET) ==
((uintptr_t)addr & PAGEOFFSET) &&
(!(vp->v_flag & VNOMAP))) {
page = 1;
} else {
page = 0;
}
/*
* Set the heap pagesize for OOB when the bss size
* is known and use_brk_lpg is not 0.
*/
if (brksize != NULL && use_brk_lpg &&
zfodsz != 0 && phdr == dataphdrp &&
(prot & PROT_WRITE)) {
size_t tlen = P2NPHASE((uintptr_t)addr +
phdr->p_filesz, PAGESIZE);
if (zfodsz > tlen) {
curproc->p_brkpageszc =
page_szc(map_pgsz(MAPPGSZ_HEAP,
curproc, addr + phdr->p_filesz +
tlen, zfodsz - tlen, 0));
}
}
if (curproc->p_brkpageszc != 0 && phdr == dataphdrp &&
(prot & PROT_WRITE)) {
uint_t szc = curproc->p_brkpageszc;
size_t pgsz = page_get_pagesize(szc);
caddr_t ebss = addr + phdr->p_memsz;
/*
* If we need extra space to keep the BSS an
* integral number of pages in size, some of
* that space may fall beyond p_brkbase, so we
* need to set p_brksize to account for it
* being (logically) part of the brk.
*/
size_t extra_zfodsz;
ASSERT(pgsz > PAGESIZE);
extra_zfodsz = P2NPHASE((uintptr_t)ebss, pgsz);
if (error = execmap(vp, addr, phdr->p_filesz,
zfodsz + extra_zfodsz, phdr->p_offset,
prot, page, szc))
goto bad;
if (brksize != NULL)
*brksize = extra_zfodsz;
} else {
if (error = execmap(vp, addr, phdr->p_filesz,
zfodsz, phdr->p_offset, prot, page, 0))
goto bad;
}
if (bssbase != NULL && addr >= *bssbase &&
phdr == dataphdrp) {
*bssbase = addr + phdr->p_filesz;
}
if (brkbase != NULL && addr >= *brkbase) {
*brkbase = addr + phdr->p_memsz;
}
*execsz += btopr(phdr->p_memsz);
break;
case PT_INTERP:
if (ptload)
goto bad;
*intphdr = phdr;
break;
case PT_SHLIB:
*stphdr = phdr;
break;
case PT_PHDR:
if (ptload)
goto bad;
*uphdr = phdr;
break;
case PT_NULL:
case PT_DYNAMIC:
case PT_NOTE:
break;
case PT_SUNWDTRACE:
if (dtphdr != NULL)
*dtphdr = phdr;
break;
default:
break;
}
phdr = (Phdr *)((caddr_t)phdr + hsize);
}
if (minaddr != NULL) {
ASSERT(mintmp != (caddr_t)-1);
*minaddr = (intptr_t)mintmp;
}
if (brkbase != NULL && secflag_enabled(curproc, PROC_SEC_ASLR)) {
size_t off;
uintptr_t base = (uintptr_t)*brkbase;
uintptr_t oend = base + *brksize;
ASSERT(ISP2(aslr_max_brk_skew));
(void) random_get_pseudo_bytes((uint8_t *)&off, sizeof (off));
base += P2PHASE(off, aslr_max_brk_skew);
base = P2ROUNDUP(base, PAGESIZE);
*brkbase = (caddr_t)base;
/*
* Above, we set *brksize to account for the possibility we
* had to grow the 'brk' in padding out the BSS to a page
* boundary.
*
* We now need to adjust that based on where we now are
* actually putting the brk.
*/
if (oend > base)
*brksize = oend - base;
else
*brksize = 0;
}
return (0);
bad:
if (error == 0)
error = EINVAL;
return (error);
}
int
elfnote(vnode_t *vp, offset_t *offsetp, int type, int descsz, void *desc,
rlim64_t rlimit, cred_t *credp)
{
Note note;
int error;
bzero(&note, sizeof (note));
bcopy("CORE", note.name, 4);
note.nhdr.n_type = type;
/*
* The System V ABI states that n_namesz must be the length of the
* string that follows the Nhdr structure including the terminating
* null. The ABI also specifies that sufficient padding should be
* included so that the description that follows the name string
* begins on a 4- or 8-byte boundary for 32- and 64-bit binaries
* respectively. However, since this change was not made correctly
* at the time of the 64-bit port, both 32- and 64-bit binaries
* descriptions are only guaranteed to begin on a 4-byte boundary.
*/
note.nhdr.n_namesz = 5;
note.nhdr.n_descsz = roundup(descsz, sizeof (Word));
if (error = core_write(vp, UIO_SYSSPACE, *offsetp, &note,
sizeof (note), rlimit, credp))
return (error);
*offsetp += sizeof (note);
if (error = core_write(vp, UIO_SYSSPACE, *offsetp, desc,
note.nhdr.n_descsz, rlimit, credp))
return (error);
*offsetp += note.nhdr.n_descsz;
return (0);
}
/*
* Copy the section data from one vnode to the section of another vnode.
*/
static void
copy_scn(Shdr *src, vnode_t *src_vp, Shdr *dst, vnode_t *dst_vp, Off *doffset,
void *buf, size_t size, cred_t *credp, rlim64_t rlimit)
{
ssize_t resid;
size_t len, n = src->sh_size;
offset_t off = 0;
while (n != 0) {
len = MIN(size, n);
if (vn_rdwr(UIO_READ, src_vp, buf, len, src->sh_offset + off,
UIO_SYSSPACE, 0, (rlim64_t)0, credp, &resid) != 0 ||
resid >= len ||
core_write(dst_vp, UIO_SYSSPACE, *doffset + off,
buf, len - resid, rlimit, credp) != 0) {
dst->sh_size = 0;
dst->sh_offset = 0;
return;
}
ASSERT(n >= len - resid);
n -= len - resid;
off += len - resid;
}
*doffset += src->sh_size;
}
#ifdef _ELF32_COMPAT
extern size_t elf_datasz_max;
#else
size_t elf_datasz_max = 1 * 1024 * 1024;
#endif
/*
* This function processes mappings that correspond to load objects to
* examine their respective sections for elfcore(). It's called once with
* v set to NULL to count the number of sections that we're going to need
* and then again with v set to some allocated buffer that we fill in with
* all the section data.
*/
static int
process_scns(core_content_t content, proc_t *p, cred_t *credp, vnode_t *vp,
Shdr *v, int nv, rlim64_t rlimit, Off *doffsetp, int *nshdrsp)
{
vnode_t *lastvp = NULL;
struct seg *seg;
int i, j;
void *data = NULL;
size_t datasz = 0;
shstrtab_t shstrtab;
struct as *as = p->p_as;
int error = 0;
if (v != NULL)
shstrtab_init(&shstrtab);
i = 1;
for (seg = AS_SEGFIRST(as); seg != NULL; seg = AS_SEGNEXT(as, seg)) {
uint_t prot;
vnode_t *mvp;
void *tmp = NULL;
caddr_t saddr = seg->s_base;
caddr_t naddr;
caddr_t eaddr;
size_t segsize;
Ehdr ehdr;
int nshdrs, shstrndx, nphdrs;
caddr_t shbase;
ssize_t shsize;
char *shstrbase;
ssize_t shstrsize;
Shdr *shdr;
const char *name;
size_t sz;
uintptr_t off;
int ctf_ndx = 0;
int symtab_ndx = 0;
/*
* Since we're just looking for text segments of load
* objects, we only care about the protection bits; we don't
* care about the actual size of the segment so we use the
* reserved size. If the segment's size is zero, there's
* something fishy going on so we ignore this segment.
*/
if (seg->s_ops != &segvn_ops ||
SEGOP_GETVP(seg, seg->s_base, &mvp) != 0 ||
mvp == lastvp || mvp == NULL || mvp->v_type != VREG ||
(segsize = pr_getsegsize(seg, 1)) == 0)
continue;
eaddr = saddr + segsize;
prot = pr_getprot(seg, 1, &tmp, &saddr, &naddr, eaddr);
pr_getprot_done(&tmp);
/*
* Skip this segment unless the protection bits look like
* what we'd expect for a text segment.
*/
if ((prot & (PROT_WRITE | PROT_EXEC)) != PROT_EXEC)
continue;
if (getelfhead(mvp, credp, &ehdr, &nshdrs, &shstrndx,
&nphdrs) != 0 ||
getelfshdr(mvp, credp, &ehdr, nshdrs, shstrndx,
&shbase, &shsize, &shstrbase, &shstrsize) != 0)
continue;
off = ehdr.e_shentsize;
for (j = 1; j < nshdrs; j++, off += ehdr.e_shentsize) {
Shdr *symtab = NULL, *strtab;
shdr = (Shdr *)(shbase + off);
if (shdr->sh_name >= shstrsize)
continue;
name = shstrbase + shdr->sh_name;
if (strcmp(name, shstrtab_data[STR_CTF]) == 0) {
if ((content & CC_CONTENT_CTF) == 0 ||
ctf_ndx != 0)
continue;
if (shdr->sh_link > 0 &&
shdr->sh_link < nshdrs) {
symtab = (Shdr *)(shbase +
shdr->sh_link * ehdr.e_shentsize);
}
if (v != NULL && i < nv - 1) {
if (shdr->sh_size > datasz &&
shdr->sh_size <= elf_datasz_max) {
if (data != NULL)
kmem_free(data, datasz);
datasz = shdr->sh_size;
data = kmem_alloc(datasz,
KM_SLEEP);
}
v[i].sh_name = shstrtab_ndx(&shstrtab,
STR_CTF);
v[i].sh_addr = (Addr)(uintptr_t)saddr;
v[i].sh_type = SHT_PROGBITS;
v[i].sh_addralign = 4;
*doffsetp = roundup(*doffsetp,
v[i].sh_addralign);
v[i].sh_offset = *doffsetp;
v[i].sh_size = shdr->sh_size;
if (symtab == NULL) {
v[i].sh_link = 0;
} else if (symtab->sh_type ==
SHT_SYMTAB &&
symtab_ndx != 0) {
v[i].sh_link =
symtab_ndx;
} else {
v[i].sh_link = i + 1;
}
copy_scn(shdr, mvp, &v[i], vp,
doffsetp, data, datasz, credp,
rlimit);
}
ctf_ndx = i++;
/*
* We've already dumped the symtab.
*/
if (symtab != NULL &&
symtab->sh_type == SHT_SYMTAB &&
symtab_ndx != 0)
continue;
} else if (strcmp(name,
shstrtab_data[STR_SYMTAB]) == 0) {
if ((content & CC_CONTENT_SYMTAB) == 0 ||
symtab != 0)
continue;
symtab = shdr;
}
if (symtab != NULL) {
if ((symtab->sh_type != SHT_DYNSYM &&
symtab->sh_type != SHT_SYMTAB) ||
symtab->sh_link == 0 ||
symtab->sh_link >= nshdrs)
continue;
strtab = (Shdr *)(shbase +
symtab->sh_link * ehdr.e_shentsize);
if (strtab->sh_type != SHT_STRTAB)
continue;
if (v != NULL && i < nv - 2) {
sz = MAX(symtab->sh_size,
strtab->sh_size);
if (sz > datasz &&
sz <= elf_datasz_max) {
if (data != NULL)
kmem_free(data, datasz);
datasz = sz;
data = kmem_alloc(datasz,
KM_SLEEP);
}
if (symtab->sh_type == SHT_DYNSYM) {
v[i].sh_name = shstrtab_ndx(
&shstrtab, STR_DYNSYM);
v[i + 1].sh_name = shstrtab_ndx(
&shstrtab, STR_DYNSTR);
} else {
v[i].sh_name = shstrtab_ndx(
&shstrtab, STR_SYMTAB);
v[i + 1].sh_name = shstrtab_ndx(
&shstrtab, STR_STRTAB);
}
v[i].sh_type = symtab->sh_type;
v[i].sh_addr = symtab->sh_addr;
if (ehdr.e_type == ET_DYN ||
v[i].sh_addr == 0)
v[i].sh_addr +=
(Addr)(uintptr_t)saddr;
v[i].sh_addralign =
symtab->sh_addralign;
*doffsetp = roundup(*doffsetp,
v[i].sh_addralign);
v[i].sh_offset = *doffsetp;
v[i].sh_size = symtab->sh_size;
v[i].sh_link = i + 1;
v[i].sh_entsize = symtab->sh_entsize;
v[i].sh_info = symtab->sh_info;
copy_scn(symtab, mvp, &v[i], vp,
doffsetp, data, datasz, credp,
rlimit);
v[i + 1].sh_type = SHT_STRTAB;
v[i + 1].sh_flags = SHF_STRINGS;
v[i + 1].sh_addr = symtab->sh_addr;
if (ehdr.e_type == ET_DYN ||
v[i + 1].sh_addr == 0)
v[i + 1].sh_addr +=
(Addr)(uintptr_t)saddr;
v[i + 1].sh_addralign =
strtab->sh_addralign;
*doffsetp = roundup(*doffsetp,
v[i + 1].sh_addralign);
v[i + 1].sh_offset = *doffsetp;
v[i + 1].sh_size = strtab->sh_size;
copy_scn(strtab, mvp, &v[i + 1], vp,
doffsetp, data, datasz, credp,
rlimit);
}
if (symtab->sh_type == SHT_SYMTAB)
symtab_ndx = i;
i += 2;
}
}
kmem_free(shstrbase, shstrsize);
kmem_free(shbase, shsize);
lastvp = mvp;
}
if (v == NULL) {
if (i == 1)
*nshdrsp = 0;
else
*nshdrsp = i + 1;
goto done;
}
if (i != nv - 1) {
cmn_err(CE_WARN, "elfcore: core dump failed for "
"process %d; address space is changing", p->p_pid);
error = EIO;
goto done;
}
v[i].sh_name = shstrtab_ndx(&shstrtab, STR_SHSTRTAB);
v[i].sh_size = shstrtab_size(&shstrtab);
v[i].sh_addralign = 1;
*doffsetp = roundup(*doffsetp, v[i].sh_addralign);
v[i].sh_offset = *doffsetp;
v[i].sh_flags = SHF_STRINGS;
v[i].sh_type = SHT_STRTAB;
if (v[i].sh_size > datasz) {
if (data != NULL)
kmem_free(data, datasz);
datasz = v[i].sh_size;
data = kmem_alloc(datasz,
KM_SLEEP);
}
shstrtab_dump(&shstrtab, data);
if ((error = core_write(vp, UIO_SYSSPACE, *doffsetp,
data, v[i].sh_size, rlimit, credp)) != 0)
goto done;
*doffsetp += v[i].sh_size;
done:
if (data != NULL)
kmem_free(data, datasz);
return (error);
}
int
elfcore(vnode_t *vp, proc_t *p, cred_t *credp, rlim64_t rlimit, int sig,
core_content_t content)
{
offset_t poffset, soffset;
Off doffset;
int error, i, nphdrs, nshdrs;
int overflow = 0;
struct seg *seg;
struct as *as = p->p_as;
union {
Ehdr ehdr;
Phdr phdr[1];
Shdr shdr[1];
} *bigwad;
size_t bigsize;
size_t phdrsz, shdrsz;
Ehdr *ehdr;
Phdr *v;
caddr_t brkbase;
size_t brksize;
caddr_t stkbase;
size_t stksize;
int ntries = 0;
klwp_t *lwp = ttolwp(curthread);
top:
/*
* Make sure we have everything we need (registers, etc.).
* All other lwps have already stopped and are in an orderly state.
*/
ASSERT(p == ttoproc(curthread));
prstop(0, 0);
AS_LOCK_ENTER(as, RW_WRITER);
nphdrs = prnsegs(as, 0) + 2; /* two CORE note sections */
/*
* Count the number of section headers we're going to need.
*/
nshdrs = 0;
if (content & (CC_CONTENT_CTF | CC_CONTENT_SYMTAB)) {
(void) process_scns(content, p, credp, NULL, NULL, NULL, 0,
NULL, &nshdrs);
}
AS_LOCK_EXIT(as);
ASSERT(nshdrs == 0 || nshdrs > 1);
/*
* The core file contents may required zero section headers, but if
* we overflow the 16 bits allotted to the program header count in
* the ELF header, we'll need that program header at index zero.
*/
if (nshdrs == 0 && nphdrs >= PN_XNUM)
nshdrs = 1;
phdrsz = nphdrs * sizeof (Phdr);
shdrsz = nshdrs * sizeof (Shdr);
bigsize = MAX(sizeof (*bigwad), MAX(phdrsz, shdrsz));
bigwad = kmem_alloc(bigsize, KM_SLEEP);
ehdr = &bigwad->ehdr;
bzero(ehdr, sizeof (*ehdr));
ehdr->e_ident[EI_MAG0] = ELFMAG0;
ehdr->e_ident[EI_MAG1] = ELFMAG1;
ehdr->e_ident[EI_MAG2] = ELFMAG2;
ehdr->e_ident[EI_MAG3] = ELFMAG3;
ehdr->e_ident[EI_CLASS] = ELFCLASS;
ehdr->e_type = ET_CORE;
#if !defined(_LP64) || defined(_ELF32_COMPAT)
#if defined(__sparc)
ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
ehdr->e_machine = EM_SPARC;
#elif defined(__i386) || defined(__i386_COMPAT)
ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
ehdr->e_machine = EM_386;
#else
#error "no recognized machine type is defined"
#endif
#else /* !defined(_LP64) || defined(_ELF32_COMPAT) */
#if defined(__sparc)
ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
ehdr->e_machine = EM_SPARCV9;
#elif defined(__amd64)
ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
ehdr->e_machine = EM_AMD64;
#else
#error "no recognized 64-bit machine type is defined"
#endif
#endif /* !defined(_LP64) || defined(_ELF32_COMPAT) */
/*
* If the count of program headers or section headers or the index
* of the section string table can't fit in the mere 16 bits
* shortsightedly allotted to them in the ELF header, we use the
* extended formats and put the real values in the section header
* as index 0.
*/
ehdr->e_version = EV_CURRENT;
ehdr->e_ehsize = sizeof (Ehdr);
if (nphdrs >= PN_XNUM)
ehdr->e_phnum = PN_XNUM;
else
ehdr->e_phnum = (unsigned short)nphdrs;
ehdr->e_phoff = sizeof (Ehdr);
ehdr->e_phentsize = sizeof (Phdr);
if (nshdrs > 0) {
if (nshdrs >= SHN_LORESERVE)
ehdr->e_shnum = 0;
else
ehdr->e_shnum = (unsigned short)nshdrs;
if (nshdrs - 1 >= SHN_LORESERVE)
ehdr->e_shstrndx = SHN_XINDEX;
else
ehdr->e_shstrndx = (unsigned short)(nshdrs - 1);
ehdr->e_shoff = ehdr->e_phoff + ehdr->e_phentsize * nphdrs;
ehdr->e_shentsize = sizeof (Shdr);
}
if (error = core_write(vp, UIO_SYSSPACE, (offset_t)0, ehdr,
sizeof (Ehdr), rlimit, credp))
goto done;
poffset = sizeof (Ehdr);
soffset = sizeof (Ehdr) + phdrsz;
doffset = sizeof (Ehdr) + phdrsz + shdrsz;
v = &bigwad->phdr[0];
bzero(v, phdrsz);
setup_old_note_header(&v[0], p);
v[0].p_offset = doffset = roundup(doffset, sizeof (Word));
doffset += v[0].p_filesz;
setup_note_header(&v[1], p);
v[1].p_offset = doffset = roundup(doffset, sizeof (Word));
doffset += v[1].p_filesz;
mutex_enter(&p->p_lock);
brkbase = p->p_brkbase;
brksize = p->p_brksize;
stkbase = p->p_usrstack - p->p_stksize;
stksize = p->p_stksize;
mutex_exit(&p->p_lock);
AS_LOCK_ENTER(as, RW_WRITER);
i = 2;
for (seg = AS_SEGFIRST(as); seg != NULL; seg = AS_SEGNEXT(as, seg)) {
caddr_t eaddr = seg->s_base + pr_getsegsize(seg, 0);
caddr_t saddr, naddr;
void *tmp = NULL;
extern struct seg_ops segspt_shmops;
for (saddr = seg->s_base; saddr < eaddr; saddr = naddr) {
uint_t prot;
size_t size;
int type;
vnode_t *mvp;
prot = pr_getprot(seg, 0, &tmp, &saddr, &naddr, eaddr);
prot &= PROT_READ | PROT_WRITE | PROT_EXEC;
if ((size = (size_t)(naddr - saddr)) == 0)
continue;
if (i == nphdrs) {
overflow++;
continue;
}
v[i].p_type = PT_LOAD;
v[i].p_vaddr = (Addr)(uintptr_t)saddr;
v[i].p_memsz = size;
if (prot & PROT_READ)
v[i].p_flags |= PF_R;
if (prot & PROT_WRITE)
v[i].p_flags |= PF_W;
if (prot & PROT_EXEC)
v[i].p_flags |= PF_X;
/*
* Figure out which mappings to include in the core.
*/
type = SEGOP_GETTYPE(seg, saddr);
if (saddr == stkbase && size == stksize) {
if (!(content & CC_CONTENT_STACK))
goto exclude;
} else if (saddr == brkbase && size == brksize) {
if (!(content & CC_CONTENT_HEAP))
goto exclude;
} else if (seg->s_ops == &segspt_shmops) {
if (type & MAP_NORESERVE) {
if (!(content & CC_CONTENT_DISM))
goto exclude;
} else {
if (!(content & CC_CONTENT_ISM))
goto exclude;
}
} else if (seg->s_ops != &segvn_ops) {
goto exclude;
} else if (type & MAP_SHARED) {
if (shmgetid(p, saddr) != SHMID_NONE) {
if (!(content & CC_CONTENT_SHM))
goto exclude;
} else if (SEGOP_GETVP(seg, seg->s_base,
&mvp) != 0 || mvp == NULL ||
mvp->v_type != VREG) {
if (!(content & CC_CONTENT_SHANON))
goto exclude;
} else {
if (!(content & CC_CONTENT_SHFILE))
goto exclude;
}
} else if (SEGOP_GETVP(seg, seg->s_base, &mvp) != 0 ||
mvp == NULL || mvp->v_type != VREG) {
if (!(content & CC_CONTENT_ANON))
goto exclude;
} else if (prot == (PROT_READ | PROT_EXEC)) {
if (!(content & CC_CONTENT_TEXT))
goto exclude;
} else if (prot == PROT_READ) {
if (!(content & CC_CONTENT_RODATA))
goto exclude;
} else {
if (!(content & CC_CONTENT_DATA))
goto exclude;
}
doffset = roundup(doffset, sizeof (Word));
v[i].p_offset = doffset;
v[i].p_filesz = size;
doffset += size;
exclude:
i++;
}
ASSERT(tmp == NULL);
}
AS_LOCK_EXIT(as);
if (overflow || i != nphdrs) {
if (ntries++ == 0) {
kmem_free(bigwad, bigsize);
overflow = 0;
goto top;
}
cmn_err(CE_WARN, "elfcore: core dump failed for "
"process %d; address space is changing", p->p_pid);
error = EIO;
goto done;
}
if ((error = core_write(vp, UIO_SYSSPACE, poffset,
v, phdrsz, rlimit, credp)) != 0)
goto done;
if ((error = write_old_elfnotes(p, sig, vp, v[0].p_offset, rlimit,
credp)) != 0)
goto done;
if ((error = write_elfnotes(p, sig, vp, v[1].p_offset, rlimit,
credp, content)) != 0)
goto done;
for (i = 2; i < nphdrs; i++) {
prkillinfo_t killinfo;
sigqueue_t *sq;
int sig, j;
if (v[i].p_filesz == 0)
continue;
/*
* If dumping out this segment fails, rather than failing
* the core dump entirely, we reset the size of the mapping
* to zero to indicate that the data is absent from the core
* file and or in the PF_SUNW_FAILURE flag to differentiate
* this from mappings that were excluded due to the core file
* content settings.
*/
if ((error = core_seg(p, vp, v[i].p_offset,
(caddr_t)(uintptr_t)v[i].p_vaddr, v[i].p_filesz,
rlimit, credp)) == 0) {
continue;
}
if ((sig = lwp->lwp_cursig) == 0) {
/*
* We failed due to something other than a signal.
* Since the space reserved for the segment is now
* unused, we stash the errno in the first four
* bytes. This undocumented interface will let us
* understand the nature of the failure.
*/
(void) core_write(vp, UIO_SYSSPACE, v[i].p_offset,
&error, sizeof (error), rlimit, credp);
v[i].p_filesz = 0;
v[i].p_flags |= PF_SUNW_FAILURE;
if ((error = core_write(vp, UIO_SYSSPACE,
poffset + sizeof (v[i]) * i, &v[i], sizeof (v[i]),
rlimit, credp)) != 0)
goto done;
continue;
}
/*
* We took a signal. We want to abort the dump entirely, but
* we also want to indicate what failed and why. We therefore
* use the space reserved for the first failing segment to
* write our error (which, for purposes of compatability with
* older core dump readers, we set to EINTR) followed by any
* siginfo associated with the signal.
*/
bzero(&killinfo, sizeof (killinfo));
killinfo.prk_error = EINTR;
sq = sig == SIGKILL ? curproc->p_killsqp : lwp->lwp_curinfo;
if (sq != NULL) {
bcopy(&sq->sq_info, &killinfo.prk_info,
sizeof (sq->sq_info));
} else {
killinfo.prk_info.si_signo = lwp->lwp_cursig;
killinfo.prk_info.si_code = SI_NOINFO;
}
#if (defined(_SYSCALL32_IMPL) || defined(_LP64))
/*
* If this is a 32-bit process, we need to translate from the
* native siginfo to the 32-bit variant. (Core readers must
* always have the same data model as their target or must
* be aware of -- and compensate for -- data model differences.)
*/
if (curproc->p_model == DATAMODEL_ILP32) {
siginfo32_t si32;
siginfo_kto32((k_siginfo_t *)&killinfo.prk_info, &si32);
bcopy(&si32, &killinfo.prk_info, sizeof (si32));
}
#endif
(void) core_write(vp, UIO_SYSSPACE, v[i].p_offset,
&killinfo, sizeof (killinfo), rlimit, credp);
/*
* For the segment on which we took the signal, indicate that
* its data now refers to a siginfo.
*/
v[i].p_filesz = 0;
v[i].p_flags |= PF_SUNW_FAILURE | PF_SUNW_KILLED |
PF_SUNW_SIGINFO;
/*
* And for every other segment, indicate that its absence
* is due to a signal.
*/
for (j = i + 1; j < nphdrs; j++) {
v[j].p_filesz = 0;
v[j].p_flags |= PF_SUNW_FAILURE | PF_SUNW_KILLED;
}
/*
* Finally, write out our modified program headers.
*/
if ((error = core_write(vp, UIO_SYSSPACE,
poffset + sizeof (v[i]) * i, &v[i],
sizeof (v[i]) * (nphdrs - i), rlimit, credp)) != 0)
goto done;
break;
}
if (nshdrs > 0) {
bzero(&bigwad->shdr[0], shdrsz);
if (nshdrs >= SHN_LORESERVE)
bigwad->shdr[0].sh_size = nshdrs;
if (nshdrs - 1 >= SHN_LORESERVE)
bigwad->shdr[0].sh_link = nshdrs - 1;
if (nphdrs >= PN_XNUM)
bigwad->shdr[0].sh_info = nphdrs;
if (nshdrs > 1) {
AS_LOCK_ENTER(as, RW_WRITER);
if ((error = process_scns(content, p, credp, vp,
&bigwad->shdr[0], nshdrs, rlimit, &doffset,
NULL)) != 0) {
AS_LOCK_EXIT(as);
goto done;
}
AS_LOCK_EXIT(as);
}
if ((error = core_write(vp, UIO_SYSSPACE, soffset,
&bigwad->shdr[0], shdrsz, rlimit, credp)) != 0)
goto done;
}
done:
kmem_free(bigwad, bigsize);
return (error);
}
#ifndef _ELF32_COMPAT
static struct execsw esw = {
#ifdef _LP64
elf64magicstr,
#else /* _LP64 */
elf32magicstr,
#endif /* _LP64 */
0,
5,
elfexec,
elfcore
};
static struct modlexec modlexec = {
&mod_execops, "exec module for elf", &esw
};
#ifdef _LP64
extern int elf32exec(vnode_t *vp, execa_t *uap, uarg_t *args,
intpdata_t *idatap, int level, long *execsz,
int setid, caddr_t exec_file, cred_t *cred,
int brand_action);
extern int elf32core(vnode_t *vp, proc_t *p, cred_t *credp,
rlim64_t rlimit, int sig, core_content_t content);
static struct execsw esw32 = {
elf32magicstr,
0,
5,
elf32exec,
elf32core
};
static struct modlexec modlexec32 = {
&mod_execops, "32-bit exec module for elf", &esw32
};
#endif /* _LP64 */
static struct modlinkage modlinkage = {
MODREV_1,
(void *)&modlexec,
#ifdef _LP64
(void *)&modlexec32,
#endif /* _LP64 */
NULL
};
int
_init(void)
{
return (mod_install(&modlinkage));
}
int
_fini(void)
{
return (mod_remove(&modlinkage));
}
int
_info(struct modinfo *modinfop)
{
return (mod_info(&modlinkage, modinfop));
}
#endif /* !_ELF32_COMPAT */