aout.c revision be10f7d91e42e379302ee5ead703b5f0bf8b47c6
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (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 2003 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/fpu/fpusystm.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/cmn_err.h>
#include <sys/debug.h>
#include <sys/exec.h>
#include <sys/exechdr.h>
#include <sys/auxv.h>
#include <sys/core.h>
#include <sys/vmparam.h>
#include <sys/archsystm.h>
#include <sys/fs/swapnode.h>
#include <sys/modctl.h>
#include <vm/anon.h>
#include <vm/as.h>
#include <vm/seg.h>
static int aoutexec(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);
static int get_aout_head(struct vnode **vpp, struct exdata *edp, long *execsz,
int *isdyn);
static int aoutcore(vnode_t *vp, proc_t *pp, cred_t *credp,
rlim64_t rlimit, int sig, core_content_t content);
#ifdef _LP64
extern int elf32exec(vnode_t *, execa_t *, uarg_t *, intpdata_t *, int,
long *, int, caddr_t, cred_t *);
extern int elf32core(vnode_t *, proc_t *, cred_t *, rlim64_t, int,
core_content_t);
#else /* _LP64 */
extern int elfexec(vnode_t *, execa_t *, uarg_t *, intpdata_t *, int,
long *, int, caddr_t, cred_t *);
extern int elfcore(vnode_t *, proc_t *, cred_t *, rlim64_t, int,
core_content_t);
#endif /* _LP64 */
char _depends_on[] = "exec/elfexec";
static struct execsw nesw = {
aout_nmagicstr,
2,
2,
aoutexec,
aoutcore
};
static struct execsw zesw = {
aout_zmagicstr,
2,
2,
aoutexec,
aoutcore
};
static struct execsw oesw = {
aout_omagicstr,
2,
2,
aoutexec,
aoutcore
};
/*
* Module linkage information for the kernel.
*/
static struct modlexec nexec = {
&mod_execops, "exec for NMAGIC", &nesw
};
static struct modlexec zexec = {
&mod_execops, "exec for ZMAGIC", &zesw
};
static struct modlexec oexec = {
&mod_execops, "exec for OMAGIC", &oesw
};
static struct modlinkage modlinkage = {
MODREV_1, &nexec, &zexec, &oexec, 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));
}
/*ARGSUSED*/
static int
aoutexec(vnode_t *vp, struct execa *uap, struct uarg *args,
struct intpdata *idatap, int level, long *execsz, int setid,
caddr_t exec_file, cred_t *cred)
{
int error;
struct exdata edp, edpout;
struct execenv exenv;
proc_t *pp = ttoproc(curthread);
struct vnode *nvp;
int pagetext, pagedata;
int dataprot = PROT_ALL;
int textprot = PROT_ALL & ~PROT_WRITE;
int isdyn;
args->to_model = DATAMODEL_ILP32;
*execsz = btopr(SINCR) + btopr(SSIZE) + btopr(NCARGS32-1);
/*
* Read in and validate the file header.
*/
if (error = get_aout_head(&vp, &edp, execsz, &isdyn))
return (error);
if (error = chkaout(&edp))
return (error);
/*
* Take a quick look to see if it looks like we will have
* enough swap space for the program to get started. This
* is not a guarantee that we will succeed, but it is definitely
* better than finding this out after we are committed to the
* new memory image. Maybe what is needed is a way to "prereserve"
* swap space for some segment mappings here.
*
* But with shared libraries the process can make it through
* the exec only to have ld.so fail to get the program going
* because its mmap's will not be able to succeed if the system
* is running low on swap space. In fact this is a far more
* common failure mode, but we cannot do much about this here
* other than add some slop to our anonymous memory resources
* requirements estimate based on some guess since we cannot know
* what else the program will really need to get to a useful state.
*
* XXX - The stack size (clrnd(SSIZE + btopr(nargc))) should also
* be used when checking for swap space. This requires some work
* since nargc is actually determined in exec_args() which is done
* after this check and hence we punt for now.
*
* nargc = SA(nc + (na + 4) * NBPW) + sizeof (struct rwindow);
*/
if (CURRENT_TOTAL_AVAILABLE_SWAP < btopr(edp.ux_dsize) + btopr(SSIZE))
return (ENOMEM);
/*
* Load the trap 0 interpreter.
*/
if (error = lookupname("/usr/4lib/sbcp", UIO_SYSSPACE, FOLLOW,
NULLVPP, &nvp)) {
goto done;
}
#ifdef _LP64
if (error = elf32exec(nvp, uap, args, idatap, level, execsz,
setid, exec_file, cred))
#else /* _LP64 */
if (error = elfexec(nvp, uap, args, idatap, level, execsz,
setid, exec_file, cred))
#endif /* _LP64 */
{
VN_RELE(nvp);
return (error);
}
VN_RELE(nvp);
/*
* Determine the a.out's characteristics.
*/
getexinfo(&edp, &edpout, &pagetext, &pagedata);
/*
* Load the a.out's text and data.
*/
if (error = execmap(edp.vp, edp.ux_txtorg, edp.ux_tsize,
(size_t)0, edp.ux_toffset, textprot, pagetext, 0))
goto done;
if (error = execmap(edp.vp, edp.ux_datorg, edp.ux_dsize,
edp.ux_bsize, edp.ux_doffset, dataprot, pagedata, 0))
goto done;
exenv.ex_brkbase = (caddr_t)edp.ux_datorg;
exenv.ex_brksize = edp.ux_dsize + edp.ux_bsize;
exenv.ex_magic = edp.ux_mag;
exenv.ex_vp = edp.vp;
setexecenv(&exenv);
done:
if (error != 0)
psignal(pp, SIGKILL);
else {
/*
* Ensure that the max fds do not exceed 256 (this is
* applicable to 4.x binaries, which is why we only
* do it on a.out files).
*/
struct rlimit64 fdno_rlim;
rctl_alloc_gp_t *gp = rctl_rlimit_set_prealloc(1);
mutex_enter(&curproc->p_lock);
(void) rctl_rlimit_get(rctlproc_legacy[RLIMIT_NOFILE], curproc,
&fdno_rlim);
if (fdno_rlim.rlim_cur > 256) {
fdno_rlim.rlim_cur = fdno_rlim.rlim_max = 256;
(void) rctl_rlimit_set(rctlproc_legacy[RLIMIT_NOFILE],
curproc, &fdno_rlim, gp,
rctlproc_flags[RLIMIT_NOFILE],
rctlproc_signals[RLIMIT_NOFILE], CRED());
} else if (fdno_rlim.rlim_max > 256) {
fdno_rlim.rlim_max = 256;
(void) rctl_rlimit_set(rctlproc_legacy[RLIMIT_NOFILE],
curproc, &fdno_rlim, gp,
rctlproc_flags[RLIMIT_NOFILE],
rctlproc_signals[RLIMIT_NOFILE], CRED());
}
mutex_exit(&curproc->p_lock);
rctl_prealloc_destroy(gp);
}
return (error);
}
/*
* Read in and validate the file header.
*/
static int
get_aout_head(struct vnode **vpp, struct exdata *edp, long *execsz, int *isdyn)
{
struct vnode *vp = *vpp;
struct exec filhdr;
int error;
ssize_t resid;
rlim64_t limit;
rlim64_t roundlimit;
if (error = vn_rdwr(UIO_READ, vp, (caddr_t)&filhdr,
(ssize_t)sizeof (filhdr), (offset_t)0, UIO_SYSSPACE, 0,
(rlim64_t)0, CRED(), &resid))
return (error);
if (resid != 0)
return (ENOEXEC);
switch (filhdr.a_magic) {
case OMAGIC:
filhdr.a_data += filhdr.a_text;
filhdr.a_text = 0;
break;
case ZMAGIC:
case NMAGIC:
break;
default:
return (ENOEXEC);
}
/*
* Check total memory requirements (in pages) for a new process
* against the available memory or upper limit of memory allowed.
*
* For the 64-bit kernel, the limit can be set large enough so that
* rounding it up to a page can overflow, so we check for btopr()
* overflowing here by comparing it with the unrounded limit in pages.
*/
*execsz += btopr(filhdr.a_text + filhdr.a_data);
limit = btop(curproc->p_vmem_ctl);
roundlimit = btopr(curproc->p_vmem_ctl);
if ((roundlimit > limit && *execsz > roundlimit) ||
(roundlimit < limit && *execsz > limit)) {
mutex_enter(&curproc->p_lock);
(void) rctl_action(rctlproc_legacy[RLIMIT_VMEM],
curproc->p_rctls, curproc, RCA_SAFE);
mutex_exit(&curproc->p_lock);
return (ENOMEM);
}
edp->ux_mach = filhdr.a_machtype;
edp->ux_tsize = filhdr.a_text;
edp->ux_dsize = filhdr.a_data;
edp->ux_bsize = filhdr.a_bss;
edp->ux_mag = filhdr.a_magic;
edp->ux_toffset = gettfile(&filhdr);
edp->ux_doffset = getdfile(&filhdr);
edp->ux_txtorg = gettmem(&filhdr);
edp->ux_datorg = getdmem(&filhdr);
edp->ux_entloc = (caddr_t)(uintptr_t)filhdr.a_entry;
edp->vp = vp;
*isdyn = filhdr.a_dynamic;
return (0);
}
static int
aoutcore(vnode_t *vp, proc_t *pp, struct cred *credp, rlim64_t rlimit, int sig,
core_content_t content)
{
#ifdef _LP64
return (elf32core(vp, pp, credp, rlimit, sig, content));
#else
return (elfcore(vp, pp, credp, rlimit, sig, content));
#endif
}