svn commit: r237477 - in head/sys: conf kern

Konstantin Belousov kib at FreeBSD.org
Sat Jun 23 10:15:24 UTC 2012


Author: kib
Date: Sat Jun 23 10:15:23 2012
New Revision: 237477
URL: http://svn.freebsd.org/changeset/base/237477

Log:
  Move the code dealing with shared page into a dedicated
  kern_sharedpage.c source file from kern_exec.c.
  
  MFC after:	  29 days

Added:
  head/sys/kern/kern_sharedpage.c
     - copied, changed from r237475, head/sys/kern/kern_exec.c
Modified:
  head/sys/conf/files
  head/sys/kern/kern_exec.c

Modified: head/sys/conf/files
==============================================================================
--- head/sys/conf/files	Sat Jun 23 10:14:51 2012	(r237476)
+++ head/sys/conf/files	Sat Jun 23 10:15:23 2012	(r237477)
@@ -2567,6 +2567,7 @@ kern/kern_rmlock.c		standard
 kern/kern_rwlock.c		standard
 kern/kern_sdt.c			optional kdtrace_hooks
 kern/kern_sema.c		standard
+kern/kern_sharedpage.c		standard
 kern/kern_shutdown.c		standard
 kern/kern_sig.c			standard
 kern/kern_switch.c		standard

Modified: head/sys/kern/kern_exec.c
==============================================================================
--- head/sys/kern/kern_exec.c	Sat Jun 23 10:14:51 2012	(r237476)
+++ head/sys/kern/kern_exec.c	Sat Jun 23 10:15:23 2012	(r237477)
@@ -28,7 +28,6 @@
 __FBSDID("$FreeBSD$");
 
 #include "opt_capsicum.h"
-#include "opt_compat.h"
 #include "opt_hwpmc_hooks.h"
 #include "opt_kdtrace.h"
 #include "opt_ktrace.h"
@@ -65,7 +64,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/sysent.h>
 #include <sys/shm.h>
 #include <sys/sysctl.h>
-#include <sys/vdso.h>
 #include <sys/vnode.h>
 #include <sys/stat.h>
 #ifdef KTRACE
@@ -1513,193 +1511,3 @@ exec_unregister(execsw_arg)
 	execsw = newexecsw;
 	return (0);
 }
-
-static struct sx shared_page_alloc_sx;
-static vm_object_t shared_page_obj;
-static int shared_page_free;
-char *shared_page_mapping;
-
-void
-shared_page_write(int base, int size, const void *data)
-{
-
-	bcopy(data, shared_page_mapping + base, size);
-}
-
-static int
-shared_page_alloc_locked(int size, int align)
-{
-	int res;
-
-	res = roundup(shared_page_free, align);
-	if (res + size >= IDX_TO_OFF(shared_page_obj->size))
-		res = -1;
-	else
-		shared_page_free = res + size;
-	return (res);
-}
-
-int
-shared_page_alloc(int size, int align)
-{
-	int res;
-
-	sx_xlock(&shared_page_alloc_sx);
-	res = shared_page_alloc_locked(size, align);
-	sx_xunlock(&shared_page_alloc_sx);
-	return (res);
-}
-
-int
-shared_page_fill(int size, int align, const void *data)
-{
-	int res;
-
-	sx_xlock(&shared_page_alloc_sx);
-	res = shared_page_alloc_locked(size, align);
-	if (res != -1)
-		shared_page_write(res, size, data);
-	sx_xunlock(&shared_page_alloc_sx);
-	return (res);
-}
-
-static void
-shared_page_init(void *dummy __unused)
-{
-	vm_page_t m;
-	vm_offset_t addr;
-
-	sx_init(&shared_page_alloc_sx, "shpsx");
-	shared_page_obj = vm_pager_allocate(OBJT_PHYS, 0, PAGE_SIZE,
-	    VM_PROT_DEFAULT, 0, NULL);
-	VM_OBJECT_LOCK(shared_page_obj);
-	m = vm_page_grab(shared_page_obj, 0, VM_ALLOC_RETRY | VM_ALLOC_NOBUSY |
-	    VM_ALLOC_ZERO);
-	m->valid = VM_PAGE_BITS_ALL;
-	VM_OBJECT_UNLOCK(shared_page_obj);
-	addr = kmem_alloc_nofault(kernel_map, PAGE_SIZE);
-	pmap_qenter(addr, &m, 1);
-	shared_page_mapping = (char *)addr;
-}
-
-SYSINIT(shp, SI_SUB_EXEC, SI_ORDER_FIRST, (sysinit_cfunc_t)shared_page_init,
-    NULL);
-
-static void
-timehands_update(struct sysentvec *sv)
-{
-	struct vdso_timehands th;
-	struct vdso_timekeep *tk;
-	uint32_t enabled, idx;
-
-	enabled = tc_fill_vdso_timehands(&th);
-	tk = (struct vdso_timekeep *)(shared_page_mapping +
-	    sv->sv_timekeep_off);
-	idx = sv->sv_timekeep_curr;
-	atomic_store_rel_32(&tk->tk_th[idx].th_gen, 0);
-	if (++idx >= VDSO_TH_NUM)
-		idx = 0;
-	sv->sv_timekeep_curr = idx;
-	if (++sv->sv_timekeep_gen == 0)
-		sv->sv_timekeep_gen = 1;
-	th.th_gen = 0;
-	if (enabled)
-		tk->tk_th[idx] = th;
-	tk->tk_enabled = enabled;
-	atomic_store_rel_32(&tk->tk_th[idx].th_gen, sv->sv_timekeep_gen);
-	tk->tk_current = idx;
-}
-
-#ifdef COMPAT_FREEBSD32
-static void
-timehands_update32(struct sysentvec *sv)
-{
-	struct vdso_timekeep32 *tk;
-	struct vdso_timehands32 th;
-	uint32_t enabled, idx;
-
-	enabled = tc_fill_vdso_timehands32(&th);
-	tk = (struct vdso_timekeep32 *)(shared_page_mapping +
-	    sv->sv_timekeep_off);
-	idx = sv->sv_timekeep_curr;
-	atomic_store_rel_32(&tk->tk_th[idx].th_gen, 0);
-	if (++idx >= VDSO_TH_NUM)
-		idx = 0;
-	sv->sv_timekeep_curr = idx;
-	if (++sv->sv_timekeep_gen == 0)
-		sv->sv_timekeep_gen = 1;
-	th.th_gen = 0;
-	if (enabled)
-		tk->tk_th[idx] = th;
-	tk->tk_enabled = enabled;
-	atomic_store_rel_32(&tk->tk_th[idx].th_gen, sv->sv_timekeep_gen);
-	tk->tk_current = idx;
-}
-#endif
-
-/*
- * This is hackish, but easiest way to avoid creating list structures
- * that needs to be iterated over from the hardclock interrupt
- * context.
- */
-static struct sysentvec *host_sysentvec;
-#ifdef COMPAT_FREEBSD32
-static struct sysentvec *compat32_sysentvec;
-#endif
-
-void
-timekeep_push_vdso(void)
-{
-
-	if (host_sysentvec != NULL && host_sysentvec->sv_timekeep_base != 0)
-		timehands_update(host_sysentvec);
-#ifdef COMPAT_FREEBSD32
-	if (compat32_sysentvec != NULL &&
-	    compat32_sysentvec->sv_timekeep_base != 0)
-		timehands_update32(compat32_sysentvec);
-#endif
-}
-
-void
-exec_sysvec_init(void *param)
-{
-	struct sysentvec *sv;
-	int tk_base;
-	uint32_t tk_ver;
-
-	sv = (struct sysentvec *)param;
-
-	if ((sv->sv_flags & SV_SHP) == 0)
-		return;
-	sv->sv_shared_page_obj = shared_page_obj;
-	sv->sv_sigcode_base = sv->sv_shared_page_base +
-	    shared_page_fill(*(sv->sv_szsigcode), 16, sv->sv_sigcode);
-	if ((sv->sv_flags & SV_ABI_MASK) != SV_ABI_FREEBSD)
-		return;
-	tk_ver = VDSO_TK_VER_CURR;
-#ifdef COMPAT_FREEBSD32
-	if ((sv->sv_flags & SV_ILP32) != 0) {
-		tk_base = shared_page_alloc(sizeof(struct vdso_timekeep32) +
-		    sizeof(struct vdso_timehands32) * VDSO_TH_NUM, 16);
-		KASSERT(tk_base != -1, ("tk_base -1 for 32bit"));
-		shared_page_write(tk_base + offsetof(struct vdso_timekeep32,
-		    tk_ver), sizeof(uint32_t), &tk_ver);
-		KASSERT(compat32_sysentvec == 0,
-		    ("Native compat32 already registered"));
-		compat32_sysentvec = sv;
-	} else {
-#endif
-		tk_base = shared_page_alloc(sizeof(struct vdso_timekeep) +
-		    sizeof(struct vdso_timehands) * VDSO_TH_NUM, 16);
-		KASSERT(tk_base != -1, ("tk_base -1 for native"));
-		shared_page_write(tk_base + offsetof(struct vdso_timekeep,
-		    tk_ver), sizeof(uint32_t), &tk_ver);
-		KASSERT(host_sysentvec == 0, ("Native already registered"));
-		host_sysentvec = sv;
-#ifdef COMPAT_FREEBSD32
-	}
-#endif
-	sv->sv_timekeep_base = sv->sv_shared_page_base + tk_base;
-	sv->sv_timekeep_off = tk_base;
-	timekeep_push_vdso();
-}

Copied and modified: head/sys/kern/kern_sharedpage.c (from r237475, head/sys/kern/kern_exec.c)
==============================================================================
--- head/sys/kern/kern_exec.c	Sat Jun 23 09:50:41 2012	(r237475, copy source)
+++ head/sys/kern/kern_sharedpage.c	Sat Jun 23 10:15:23 2012	(r237477)
@@ -1,5 +1,5 @@
 /*-
- * Copyright (c) 1993, David Greenman
+ * Copyright (c) 2010, 2012 Konstantin Belousov <kib at FreeBSD.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -27,1493 +27,28 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
-#include "opt_capsicum.h"
 #include "opt_compat.h"
-#include "opt_hwpmc_hooks.h"
-#include "opt_kdtrace.h"
-#include "opt_ktrace.h"
 #include "opt_vm.h"
 
 #include <sys/param.h>
-#include <sys/capability.h>
 #include <sys/systm.h>
-#include <sys/capability.h>
-#include <sys/eventhandler.h>
+#include <sys/kernel.h>
 #include <sys/lock.h>
 #include <sys/mutex.h>
-#include <sys/sysproto.h>
-#include <sys/signalvar.h>
-#include <sys/kernel.h>
-#include <sys/mount.h>
-#include <sys/filedesc.h>
-#include <sys/fcntl.h>
-#include <sys/acct.h>
-#include <sys/exec.h>
-#include <sys/imgact.h>
-#include <sys/imgact_elf.h>
-#include <sys/wait.h>
-#include <sys/malloc.h>
-#include <sys/priv.h>
-#include <sys/proc.h>
-#include <sys/pioctl.h>
-#include <sys/namei.h>
-#include <sys/resourcevar.h>
-#include <sys/sched.h>
-#include <sys/sdt.h>
-#include <sys/sf_buf.h>
-#include <sys/syscallsubr.h>
 #include <sys/sysent.h>
-#include <sys/shm.h>
 #include <sys/sysctl.h>
 #include <sys/vdso.h>
-#include <sys/vnode.h>
-#include <sys/stat.h>
-#ifdef KTRACE
-#include <sys/ktrace.h>
-#endif
 
 #include <vm/vm.h>
 #include <vm/vm_param.h>
 #include <vm/pmap.h>
-#include <vm/vm_page.h>
-#include <vm/vm_map.h>
-#include <vm/vm_kern.h>
 #include <vm/vm_extern.h>
+#include <vm/vm_kern.h>
+#include <vm/vm_map.h>
 #include <vm/vm_object.h>
+#include <vm/vm_page.h>
 #include <vm/vm_pager.h>
 
-#ifdef	HWPMC_HOOKS
-#include <sys/pmckern.h>
-#endif
-
-#include <machine/reg.h>
-
-#include <security/audit/audit.h>
-#include <security/mac/mac_framework.h>
-
-#ifdef KDTRACE_HOOKS
-#include <sys/dtrace_bsd.h>
-dtrace_execexit_func_t	dtrace_fasttrap_exec;
-#endif
-
-SDT_PROVIDER_DECLARE(proc);
-SDT_PROBE_DEFINE(proc, kernel, , exec, exec);
-SDT_PROBE_ARGTYPE(proc, kernel, , exec, 0, "char *");
-SDT_PROBE_DEFINE(proc, kernel, , exec_failure, exec-failure);
-SDT_PROBE_ARGTYPE(proc, kernel, , exec_failure, 0, "int");
-SDT_PROBE_DEFINE(proc, kernel, , exec_success, exec-success);
-SDT_PROBE_ARGTYPE(proc, kernel, , exec_success, 0, "char *");
-
-MALLOC_DEFINE(M_PARGS, "proc-args", "Process arguments");
-
-static int sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS);
-static int sysctl_kern_usrstack(SYSCTL_HANDLER_ARGS);
-static int sysctl_kern_stackprot(SYSCTL_HANDLER_ARGS);
-static int do_execve(struct thread *td, struct image_args *args,
-    struct mac *mac_p);
-
-/* XXX This should be vm_size_t. */
-SYSCTL_PROC(_kern, KERN_PS_STRINGS, ps_strings, CTLTYPE_ULONG|CTLFLAG_RD,
-    NULL, 0, sysctl_kern_ps_strings, "LU", "");
-
-/* XXX This should be vm_size_t. */
-SYSCTL_PROC(_kern, KERN_USRSTACK, usrstack, CTLTYPE_ULONG|CTLFLAG_RD|
-    CTLFLAG_CAPRD, NULL, 0, sysctl_kern_usrstack, "LU", "");
-
-SYSCTL_PROC(_kern, OID_AUTO, stackprot, CTLTYPE_INT|CTLFLAG_RD,
-    NULL, 0, sysctl_kern_stackprot, "I", "");
-
-u_long ps_arg_cache_limit = PAGE_SIZE / 16;
-SYSCTL_ULONG(_kern, OID_AUTO, ps_arg_cache_limit, CTLFLAG_RW, 
-    &ps_arg_cache_limit, 0, "");
-
-static int map_at_zero = 0;
-TUNABLE_INT("security.bsd.map_at_zero", &map_at_zero);
-SYSCTL_INT(_security_bsd, OID_AUTO, map_at_zero, CTLFLAG_RW, &map_at_zero, 0,
-    "Permit processes to map an object at virtual address 0.");
-
-static int
-sysctl_kern_ps_strings(SYSCTL_HANDLER_ARGS)
-{
-	struct proc *p;
-	int error;
-
-	p = curproc;
-#ifdef SCTL_MASK32
-	if (req->flags & SCTL_MASK32) {
-		unsigned int val;
-		val = (unsigned int)p->p_sysent->sv_psstrings;
-		error = SYSCTL_OUT(req, &val, sizeof(val));
-	} else
-#endif
-		error = SYSCTL_OUT(req, &p->p_sysent->sv_psstrings,
-		   sizeof(p->p_sysent->sv_psstrings));
-	return error;
-}
-
-static int
-sysctl_kern_usrstack(SYSCTL_HANDLER_ARGS)
-{
-	struct proc *p;
-	int error;
-
-	p = curproc;
-#ifdef SCTL_MASK32
-	if (req->flags & SCTL_MASK32) {
-		unsigned int val;
-		val = (unsigned int)p->p_sysent->sv_usrstack;
-		error = SYSCTL_OUT(req, &val, sizeof(val));
-	} else
-#endif
-		error = SYSCTL_OUT(req, &p->p_sysent->sv_usrstack,
-		    sizeof(p->p_sysent->sv_usrstack));
-	return error;
-}
-
-static int
-sysctl_kern_stackprot(SYSCTL_HANDLER_ARGS)
-{
-	struct proc *p;
-
-	p = curproc;
-	return (SYSCTL_OUT(req, &p->p_sysent->sv_stackprot,
-	    sizeof(p->p_sysent->sv_stackprot)));
-}
-
-/*
- * Each of the items is a pointer to a `const struct execsw', hence the
- * double pointer here.
- */
-static const struct execsw **execsw;
-
-#ifndef _SYS_SYSPROTO_H_
-struct execve_args {
-	char    *fname; 
-	char    **argv;
-	char    **envv; 
-};
-#endif
-
-int
-sys_execve(td, uap)
-	struct thread *td;
-	struct execve_args /* {
-		char *fname;
-		char **argv;
-		char **envv;
-	} */ *uap;
-{
-	int error;
-	struct image_args args;
-
-	error = exec_copyin_args(&args, uap->fname, UIO_USERSPACE,
-	    uap->argv, uap->envv);
-	if (error == 0)
-		error = kern_execve(td, &args, NULL);
-	return (error);
-}
-
-#ifndef _SYS_SYSPROTO_H_
-struct fexecve_args {
-	int	fd;
-	char	**argv;
-	char	**envv;
-}
-#endif
-int
-sys_fexecve(struct thread *td, struct fexecve_args *uap)
-{
-	int error;
-	struct image_args args;
-
-	error = exec_copyin_args(&args, NULL, UIO_SYSSPACE,
-	    uap->argv, uap->envv);
-	if (error == 0) {
-		args.fd = uap->fd;
-		error = kern_execve(td, &args, NULL);
-	}
-	return (error);
-}
-
-#ifndef _SYS_SYSPROTO_H_
-struct __mac_execve_args {
-	char	*fname;
-	char	**argv;
-	char	**envv;
-	struct mac	*mac_p;
-};
-#endif
-
-int
-sys___mac_execve(td, uap)
-	struct thread *td;
-	struct __mac_execve_args /* {
-		char *fname;
-		char **argv;
-		char **envv;
-		struct mac *mac_p;
-	} */ *uap;
-{
-#ifdef MAC
-	int error;
-	struct image_args args;
-
-	error = exec_copyin_args(&args, uap->fname, UIO_USERSPACE,
-	    uap->argv, uap->envv);
-	if (error == 0)
-		error = kern_execve(td, &args, uap->mac_p);
-	return (error);
-#else
-	return (ENOSYS);
-#endif
-}
-
-/*
- * XXX: kern_execve has the astonishing property of not always returning to
- * the caller.  If sufficiently bad things happen during the call to
- * do_execve(), it can end up calling exit1(); as a result, callers must
- * avoid doing anything which they might need to undo (e.g., allocating
- * memory).
- */
-int
-kern_execve(td, args, mac_p)
-	struct thread *td;
-	struct image_args *args;
-	struct mac *mac_p;
-{
-	struct proc *p = td->td_proc;
-	int error;
-
-	AUDIT_ARG_ARGV(args->begin_argv, args->argc,
-	    args->begin_envv - args->begin_argv);
-	AUDIT_ARG_ENVV(args->begin_envv, args->envc,
-	    args->endp - args->begin_envv);
-	if (p->p_flag & P_HADTHREADS) {
-		PROC_LOCK(p);
-		if (thread_single(SINGLE_BOUNDARY)) {
-			PROC_UNLOCK(p);
-	       		exec_free_args(args);
-			return (ERESTART);	/* Try again later. */
-		}
-		PROC_UNLOCK(p);
-	}
-
-	error = do_execve(td, args, mac_p);
-
-	if (p->p_flag & P_HADTHREADS) {
-		PROC_LOCK(p);
-		/*
-		 * If success, we upgrade to SINGLE_EXIT state to
-		 * force other threads to suicide.
-		 */
-		if (error == 0)
-			thread_single(SINGLE_EXIT);
-		else
-			thread_single_end();
-		PROC_UNLOCK(p);
-	}
-
-	return (error);
-}
-
-/*
- * In-kernel implementation of execve().  All arguments are assumed to be
- * userspace pointers from the passed thread.
- */
-static int
-do_execve(td, args, mac_p)
-	struct thread *td;
-	struct image_args *args;
-	struct mac *mac_p;
-{
-	struct proc *p = td->td_proc;
-	struct nameidata nd;
-	struct ucred *newcred = NULL, *oldcred;
-	struct uidinfo *euip;
-	register_t *stack_base;
-	int error, i;
-	struct image_params image_params, *imgp;
-	struct vattr attr;
-	int (*img_first)(struct image_params *);
-	struct pargs *oldargs = NULL, *newargs = NULL;
-	struct sigacts *oldsigacts, *newsigacts;
-#ifdef KTRACE
-	struct vnode *tracevp = NULL;
-	struct ucred *tracecred = NULL;
-#endif
-	struct vnode *textvp = NULL, *binvp = NULL;
-	int credential_changing;
-	int vfslocked;
-	int textset;
-#ifdef MAC
-	struct label *interpvplabel = NULL;
-	int will_transition;
-#endif
-#ifdef HWPMC_HOOKS
-	struct pmckern_procexec pe;
-#endif
-	static const char fexecv_proc_title[] = "(fexecv)";
-
-	vfslocked = 0;
-	imgp = &image_params;
-
-	/*
-	 * Lock the process and set the P_INEXEC flag to indicate that
-	 * it should be left alone until we're done here.  This is
-	 * necessary to avoid race conditions - e.g. in ptrace() -
-	 * that might allow a local user to illicitly obtain elevated
-	 * privileges.
-	 */
-	PROC_LOCK(p);
-	KASSERT((p->p_flag & P_INEXEC) == 0,
-	    ("%s(): process already has P_INEXEC flag", __func__));
-	p->p_flag |= P_INEXEC;
-	PROC_UNLOCK(p);
-
-	/*
-	 * Initialize part of the common data
-	 */
-	imgp->proc = p;
-	imgp->execlabel = NULL;
-	imgp->attr = &attr;
-	imgp->entry_addr = 0;
-	imgp->reloc_base = 0;
-	imgp->vmspace_destroyed = 0;
-	imgp->interpreted = 0;
-	imgp->opened = 0;
-	imgp->interpreter_name = NULL;
-	imgp->auxargs = NULL;
-	imgp->vp = NULL;
-	imgp->object = NULL;
-	imgp->firstpage = NULL;
-	imgp->ps_strings = 0;
-	imgp->auxarg_size = 0;
-	imgp->args = args;
-	imgp->execpath = imgp->freepath = NULL;
-	imgp->execpathp = 0;
-	imgp->canary = 0;
-	imgp->canarylen = 0;
-	imgp->pagesizes = 0;
-	imgp->pagesizeslen = 0;
-	imgp->stack_prot = 0;
-
-#ifdef MAC
-	error = mac_execve_enter(imgp, mac_p);
-	if (error)
-		goto exec_fail;
-#endif
-
-	imgp->image_header = NULL;
-
-	/*
-	 * Translate the file name. namei() returns a vnode pointer
-	 *	in ni_vp amoung other things.
-	 *
-	 * XXXAUDIT: It would be desirable to also audit the name of the
-	 * interpreter if this is an interpreted binary.
-	 */
-	if (args->fname != NULL) {
-		NDINIT(&nd, LOOKUP, ISOPEN | LOCKLEAF | FOLLOW | SAVENAME
-		    | MPSAFE | AUDITVNODE1, UIO_SYSSPACE, args->fname, td);
-	}
-
-	SDT_PROBE(proc, kernel, , exec, args->fname, 0, 0, 0, 0 );
-
-interpret:
-	if (args->fname != NULL) {
-#ifdef CAPABILITY_MODE
-		/*
-		 * While capability mode can't reach this point via direct
-		 * path arguments to execve(), we also don't allow
-		 * interpreters to be used in capability mode (for now).
-		 * Catch indirect lookups and return a permissions error.
-		 */
-		if (IN_CAPABILITY_MODE(td)) {
-			error = ECAPMODE;
-			goto exec_fail;
-		}
-#endif
-		error = namei(&nd);
-		if (error)
-			goto exec_fail;
-
-		vfslocked = NDHASGIANT(&nd);
-		binvp  = nd.ni_vp;
-		imgp->vp = binvp;
-	} else {
-		AUDIT_ARG_FD(args->fd);
-		/*
-		 * Some might argue that CAP_READ and/or CAP_MMAP should also
-		 * be required here; such arguments will be entertained.
-		 */
-		error = fgetvp_read(td, args->fd, CAP_FEXECVE, &binvp);
-		if (error)
-			goto exec_fail;
-		vfslocked = VFS_LOCK_GIANT(binvp->v_mount);
-		vn_lock(binvp, LK_EXCLUSIVE | LK_RETRY);
-		AUDIT_ARG_VNODE1(binvp);
-		imgp->vp = binvp;
-	}
-
-	/*
-	 * Check file permissions (also 'opens' file)
-	 */
-	error = exec_check_permissions(imgp);
-	if (error)
-		goto exec_fail_dealloc;
-
-	imgp->object = imgp->vp->v_object;
-	if (imgp->object != NULL)
-		vm_object_reference(imgp->object);
-
-	/*
-	 * Set VV_TEXT now so no one can write to the executable while we're
-	 * activating it.
-	 *
-	 * Remember if this was set before and unset it in case this is not
-	 * actually an executable image.
-	 */
-	textset = imgp->vp->v_vflag & VV_TEXT;
-	ASSERT_VOP_ELOCKED(imgp->vp, "vv_text");
-	imgp->vp->v_vflag |= VV_TEXT;
-
-	error = exec_map_first_page(imgp);
-	if (error)
-		goto exec_fail_dealloc;
-
-	imgp->proc->p_osrel = 0;
-	/*
-	 *	If the current process has a special image activator it
-	 *	wants to try first, call it.   For example, emulating shell
-	 *	scripts differently.
-	 */
-	error = -1;
-	if ((img_first = imgp->proc->p_sysent->sv_imgact_try) != NULL)
-		error = img_first(imgp);
-
-	/*
-	 *	Loop through the list of image activators, calling each one.
-	 *	An activator returns -1 if there is no match, 0 on success,
-	 *	and an error otherwise.
-	 */
-	for (i = 0; error == -1 && execsw[i]; ++i) {
-		if (execsw[i]->ex_imgact == NULL ||
-		    execsw[i]->ex_imgact == img_first) {
-			continue;
-		}
-		error = (*execsw[i]->ex_imgact)(imgp);
-	}
-
-	if (error) {
-		if (error == -1) {
-			if (textset == 0) {
-				ASSERT_VOP_ELOCKED(imgp->vp, "vv_text");
-				imgp->vp->v_vflag &= ~VV_TEXT;
-			}
-			error = ENOEXEC;
-		}
-		goto exec_fail_dealloc;
-	}
-
-	/*
-	 * Special interpreter operation, cleanup and loop up to try to
-	 * activate the interpreter.
-	 */
-	if (imgp->interpreted) {
-		exec_unmap_first_page(imgp);
-		/*
-		 * VV_TEXT needs to be unset for scripts.  There is a short
-		 * period before we determine that something is a script where
-		 * VV_TEXT will be set. The vnode lock is held over this
-		 * entire period so nothing should illegitimately be blocked.
-		 */
-		imgp->vp->v_vflag &= ~VV_TEXT;
-		/* free name buffer and old vnode */
-		if (args->fname != NULL)
-			NDFREE(&nd, NDF_ONLY_PNBUF);
-#ifdef MAC
-		mac_execve_interpreter_enter(binvp, &interpvplabel);
-#endif
-		if (imgp->opened) {
-			VOP_CLOSE(binvp, FREAD, td->td_ucred, td);
-			imgp->opened = 0;
-		}
-		vput(binvp);
-		vm_object_deallocate(imgp->object);
-		imgp->object = NULL;
-		VFS_UNLOCK_GIANT(vfslocked);
-		vfslocked = 0;
-		/* set new name to that of the interpreter */
-		NDINIT(&nd, LOOKUP, LOCKLEAF | FOLLOW | SAVENAME | MPSAFE,
-		    UIO_SYSSPACE, imgp->interpreter_name, td);
-		args->fname = imgp->interpreter_name;
-		goto interpret;
-	}
-
-	/*
-	 * NB: We unlock the vnode here because it is believed that none
-	 * of the sv_copyout_strings/sv_fixup operations require the vnode.
-	 */
-	VOP_UNLOCK(imgp->vp, 0);
-
-	/*
-	 * Do the best to calculate the full path to the image file.
-	 */
-	if (imgp->auxargs != NULL &&
-	    ((args->fname != NULL && args->fname[0] == '/') ||
-	     vn_fullpath(td, imgp->vp, &imgp->execpath, &imgp->freepath) != 0))
-		imgp->execpath = args->fname;
-
-	/*
-	 * Copy out strings (args and env) and initialize stack base
-	 */
-	if (p->p_sysent->sv_copyout_strings)
-		stack_base = (*p->p_sysent->sv_copyout_strings)(imgp);
-	else
-		stack_base = exec_copyout_strings(imgp);
-
-	/*
-	 * If custom stack fixup routine present for this process
-	 * let it do the stack setup.
-	 * Else stuff argument count as first item on stack
-	 */
-	if (p->p_sysent->sv_fixup != NULL)
-		(*p->p_sysent->sv_fixup)(&stack_base, imgp);
-	else
-		suword(--stack_base, imgp->args->argc);
-
-	/*
-	 * For security and other reasons, the file descriptor table cannot
-	 * be shared after an exec.
-	 */
-	fdunshare(p, td);
-
-	/*
-	 * Malloc things before we need locks.
-	 */
-	newcred = crget();
-	euip = uifind(attr.va_uid);
-	i = imgp->args->begin_envv - imgp->args->begin_argv;
-	/* Cache arguments if they fit inside our allowance */
-	if (ps_arg_cache_limit >= i + sizeof(struct pargs)) {
-		newargs = pargs_alloc(i);
-		bcopy(imgp->args->begin_argv, newargs->ar_args, i);
-	}
-
-	/* close files on exec */
-	fdcloseexec(td);
-	vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
-
-	/* Get a reference to the vnode prior to locking the proc */
-	VREF(binvp);
-
-	/*
-	 * For security and other reasons, signal handlers cannot
-	 * be shared after an exec. The new process gets a copy of the old
-	 * handlers. In execsigs(), the new process will have its signals
-	 * reset.
-	 */
-	PROC_LOCK(p);
-	oldcred = crcopysafe(p, newcred);
-	if (sigacts_shared(p->p_sigacts)) {
-		oldsigacts = p->p_sigacts;
-		PROC_UNLOCK(p);
-		newsigacts = sigacts_alloc();
-		sigacts_copy(newsigacts, oldsigacts);
-		PROC_LOCK(p);
-		p->p_sigacts = newsigacts;
-	} else
-		oldsigacts = NULL;
-
-	/* Stop profiling */
-	stopprofclock(p);
-
-	/* reset caught signals */
-	execsigs(p);
-
-	/* name this process - nameiexec(p, ndp) */
-	bzero(p->p_comm, sizeof(p->p_comm));
-	if (args->fname)
-		bcopy(nd.ni_cnd.cn_nameptr, p->p_comm,
-		    min(nd.ni_cnd.cn_namelen, MAXCOMLEN));
-	else if (vn_commname(binvp, p->p_comm, sizeof(p->p_comm)) != 0)
-		bcopy(fexecv_proc_title, p->p_comm, sizeof(fexecv_proc_title));
-	bcopy(p->p_comm, td->td_name, sizeof(td->td_name));
-#ifdef KTR
-	sched_clear_tdname(td);
-#endif
-
-	/*
-	 * mark as execed, wakeup the process that vforked (if any) and tell
-	 * it that it now has its own resources back
-	 */
-	p->p_flag |= P_EXEC;
-	if (p->p_pptr && (p->p_flag & P_PPWAIT)) {
-		p->p_flag &= ~P_PPWAIT;
-		cv_broadcast(&p->p_pwait);
-	}
-
-	/*
-	 * Implement image setuid/setgid.
-	 *
-	 * Don't honor setuid/setgid if the filesystem prohibits it or if
-	 * the process is being traced.
-	 *
-	 * We disable setuid/setgid/etc in compatibility mode on the basis
-	 * that most setugid applications are not written with that
-	 * environment in mind, and will therefore almost certainly operate
-	 * incorrectly. In principle there's no reason that setugid
-	 * applications might not be useful in capability mode, so we may want
-	 * to reconsider this conservative design choice in the future.
-	 *
-	 * XXXMAC: For the time being, use NOSUID to also prohibit
-	 * transitions on the file system.
-	 */
-	credential_changing = 0;
-	credential_changing |= (attr.va_mode & S_ISUID) && oldcred->cr_uid !=
-	    attr.va_uid;
-	credential_changing |= (attr.va_mode & S_ISGID) && oldcred->cr_gid !=
-	    attr.va_gid;
-#ifdef MAC
-	will_transition = mac_vnode_execve_will_transition(oldcred, imgp->vp,
-	    interpvplabel, imgp);
-	credential_changing |= will_transition;
-#endif
-
-	if (credential_changing &&
-#ifdef CAPABILITY_MODE
-	    ((oldcred->cr_flags & CRED_FLAG_CAPMODE) == 0) &&
-#endif
-	    (imgp->vp->v_mount->mnt_flag & MNT_NOSUID) == 0 &&
-	    (p->p_flag & P_TRACED) == 0) {
-		/*
-		 * Turn off syscall tracing for set-id programs, except for
-		 * root.  Record any set-id flags first to make sure that
-		 * we do not regain any tracing during a possible block.
-		 */
-		setsugid(p);
-
-#ifdef KTRACE
-		if (priv_check_cred(oldcred, PRIV_DEBUG_DIFFCRED, 0))
-			ktrprocexec(p, &tracecred, &tracevp);
-#endif
-		/*
-		 * Close any file descriptors 0..2 that reference procfs,
-		 * then make sure file descriptors 0..2 are in use.
-		 *
-		 * setugidsafety() may call closef() and then pfind()
-		 * which may grab the process lock.
-		 * fdcheckstd() may call falloc() which may block to
-		 * allocate memory, so temporarily drop the process lock.
-		 */
-		PROC_UNLOCK(p);
-		VOP_UNLOCK(imgp->vp, 0);
-		setugidsafety(td);
-		error = fdcheckstd(td);
-		vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
-		if (error != 0)
-			goto done1;
-		PROC_LOCK(p);
-		/*
-		 * Set the new credentials.
-		 */
-		if (attr.va_mode & S_ISUID)
-			change_euid(newcred, euip);
-		if (attr.va_mode & S_ISGID)
-			change_egid(newcred, attr.va_gid);
-#ifdef MAC
-		if (will_transition) {
-			mac_vnode_execve_transition(oldcred, newcred, imgp->vp,
-			    interpvplabel, imgp);
-		}
-#endif
-		/*
-		 * Implement correct POSIX saved-id behavior.
-		 *
-		 * XXXMAC: Note that the current logic will save the
-		 * uid and gid if a MAC domain transition occurs, even
-		 * though maybe it shouldn't.
-		 */
-		change_svuid(newcred, newcred->cr_uid);
-		change_svgid(newcred, newcred->cr_gid);
-		p->p_ucred = newcred;
-		newcred = NULL;
-	} else {
-		if (oldcred->cr_uid == oldcred->cr_ruid &&
-		    oldcred->cr_gid == oldcred->cr_rgid)
-			p->p_flag &= ~P_SUGID;
-		/*
-		 * Implement correct POSIX saved-id behavior.
-		 *
-		 * XXX: It's not clear that the existing behavior is
-		 * POSIX-compliant.  A number of sources indicate that the
-		 * saved uid/gid should only be updated if the new ruid is
-		 * not equal to the old ruid, or the new euid is not equal
-		 * to the old euid and the new euid is not equal to the old
-		 * ruid.  The FreeBSD code always updates the saved uid/gid.
-		 * Also, this code uses the new (replaced) euid and egid as
-		 * the source, which may or may not be the right ones to use.
-		 */
-		if (oldcred->cr_svuid != oldcred->cr_uid ||
-		    oldcred->cr_svgid != oldcred->cr_gid) {
-			change_svuid(newcred, newcred->cr_uid);
-			change_svgid(newcred, newcred->cr_gid);
-			p->p_ucred = newcred;
-			newcred = NULL;
-		}
-	}
-
-	/*
-	 * Store the vp for use in procfs.  This vnode was referenced prior
-	 * to locking the proc lock.
-	 */
-	textvp = p->p_textvp;
-	p->p_textvp = binvp;
-
-#ifdef KDTRACE_HOOKS
-	/*
-	 * Tell the DTrace fasttrap provider about the exec if it
-	 * has declared an interest.
-	 */
-	if (dtrace_fasttrap_exec)
-		dtrace_fasttrap_exec(p);
-#endif
-
-	/*
-	 * Notify others that we exec'd, and clear the P_INEXEC flag
-	 * as we're now a bona fide freshly-execed process.
-	 */
-	KNOTE_LOCKED(&p->p_klist, NOTE_EXEC);
-	p->p_flag &= ~P_INEXEC;
-
-	/* clear "fork but no exec" flag, as we _are_ execing */
-	p->p_acflag &= ~AFORK;

*** DIFF OUTPUT TRUNCATED AT 1000 LINES ***


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