static int
dtrace_getustack_common(uint64_t *pcstack, int pcstack_limit, uintptr_t pc,
uintptr_t sp)
{
proc_t *p = curproc;
int ret = 0;
ASSERT(pcstack == NULL || pcstack_limit > 0);
while (pc != 0) {
ret++;
if (pcstack != NULL) {
*pcstack++ = (uint64_t)pc;
pcstack_limit--;
if (pcstack_limit <= 0)
break;
}
if (sp == 0)
break;
if (SV_PROC_FLAG(p, SV_ILP32)) {
pc = dtrace_fuword32((void *)(sp + RETURN_OFFSET));
sp = dtrace_fuword32((void *)sp);
}
else {
pc = dtrace_fuword64((void *)(sp + RETURN_OFFSET64));
sp = dtrace_fuword64((void *)sp);
}
}
return (ret);
}
/*
* Set that machine state for performing an upcall that starts
* the entry function with the given argument.
*/
void
cpu_set_upcall(struct thread *td, void (*entry)(void *), void *arg,
stack_t *stack)
{
/*
* Do any extra cleaning that needs to be done.
* The thread may have optional components
* that are not present in a fresh thread.
* This may be a recycled thread so make it look
* as though it's newly allocated.
*/
cpu_thread_clean(td);
#ifdef COMPAT_FREEBSD32
if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
/*
* Set the trap frame to point at the beginning of the entry
* function.
*/
td->td_frame->tf_rbp = 0;
td->td_frame->tf_rsp =
(((uintptr_t)stack->ss_sp + stack->ss_size - 4) & ~0x0f) - 4;
td->td_frame->tf_rip = (uintptr_t)entry;
/* Return address sentinel value to stop stack unwinding. */
suword32((void *)td->td_frame->tf_rsp, 0);
/* Pass the argument to the entry point. */
suword32((void *)(td->td_frame->tf_rsp + sizeof(int32_t)),
(uint32_t)(uintptr_t)arg);
return;
}
#endif
/*
* Set the trap frame to point at the beginning of the uts
* function.
*/
td->td_frame->tf_rbp = 0;
td->td_frame->tf_rsp =
((register_t)stack->ss_sp + stack->ss_size) & ~0x0f;
td->td_frame->tf_rsp -= 8;
td->td_frame->tf_rip = (register_t)entry;
td->td_frame->tf_ds = _udatasel;
td->td_frame->tf_es = _udatasel;
td->td_frame->tf_fs = _ufssel;
td->td_frame->tf_gs = _ugssel;
td->td_frame->tf_flags = TF_HASSEGS;
/* Return address sentinel value to stop stack unwinding. */
suword((void *)td->td_frame->tf_rsp, 0);
/* Pass the argument to the entry point. */
td->td_frame->tf_rdi = (register_t)arg;
}
int
procfs_doprocfpregs(PFS_FILL_ARGS)
{
int error;
struct fpreg r;
struct thread *td2;
#ifdef COMPAT_FREEBSD32
struct fpreg32 r32;
int wrap32 = 0;
#endif
if (uio->uio_offset != 0)
return (0);
PROC_LOCK(p);
PROC_ASSERT_HELD(p);
if (p_candebug(td, p)) {
PROC_UNLOCK(p);
return (EPERM);
}
if (!P_SHOULDSTOP(p)) {
PROC_UNLOCK(p);
return (EBUSY);
}
td2 = FIRST_THREAD_IN_PROC(p);
#ifdef COMPAT_FREEBSD32
if (SV_CURPROC_FLAG(SV_ILP32)) {
if (SV_PROC_FLAG(td2->td_proc, SV_ILP32) == 0) {
PROC_UNLOCK(p);
return (EINVAL);
}
wrap32 = 1;
memset(&r32, 0, sizeof(r32));
} else
#endif
memset(&r, 0, sizeof(r));
error = PROC(read, fpregs, td2, &r);
if (error == 0) {
PROC_UNLOCK(p);
error = UIOMOVE_FROMBUF(r, uio);
PROC_LOCK(p);
}
if (error == 0 && uio->uio_rw == UIO_WRITE) {
if (!P_SHOULDSTOP(p))
error = EBUSY;
else
/* XXXKSE: */
error = PROC(write, fpregs, td2, &r);
}
PROC_UNLOCK(p);
return (error);
}
static void
linux_fixup_prot(struct thread *td, int *prot)
{
struct linux_pemuldata *pem;
if (SV_PROC_FLAG(td->td_proc, SV_ILP32) && *prot & PROT_READ) {
pem = pem_find(td->td_proc);
if (pem->persona & LINUX_READ_IMPLIES_EXEC)
*prot |= PROT_EXEC;
}
}
int
procfs_doprocdbregs(PFS_FILL_ARGS)
{
int error;
struct dbreg r;
struct thread *td2;
#ifdef COMPAT_FREEBSD32
struct dbreg32 r32;
int wrap32 = 0;
#endif
if (uio->uio_offset != 0)
return (0);
PROC_LOCK(p);
KASSERT(p->p_lock > 0, ("proc not held"));
if (p_candebug(td, p) != 0) {
PROC_UNLOCK(p);
return (EPERM);
}
td2 = FIRST_THREAD_IN_PROC(p);
#ifdef COMPAT_FREEBSD32
if (SV_CURPROC_FLAG(SV_ILP32)) {
if (SV_PROC_FLAG(td2->td_proc, SV_ILP32) == 0) {
PROC_UNLOCK(p);
return (EINVAL);
}
wrap32 = 1;
}
#endif
error = PROC(read, dbregs, td2, &r);
if (error == 0) {
PROC_UNLOCK(p);
error = UIOMOVE_FROMBUF(r, uio);
PROC_LOCK(p);
}
if (error == 0 && uio->uio_rw == UIO_WRITE) {
if (!P_SHOULDSTOP(p)) /* XXXKSE should be P_TRACED? */
error = EBUSY;
else
/* XXXKSE: */
error = PROC(write, dbregs, td2, &r);
}
PROC_UNLOCK(p);
return (error);
}
int
cpu_set_user_tls(struct thread *td, void *tls_base)
{
#if defined(__mips_n64) && defined(COMPAT_FREEBSD32)
if (td->td_proc && SV_PROC_FLAG(td->td_proc, SV_ILP32))
td->td_md.md_tls_tcb_offset = TLS_TP_OFFSET + TLS_TCB_SIZE32;
else
#endif
td->td_md.md_tls_tcb_offset = TLS_TP_OFFSET + TLS_TCB_SIZE;
td->td_md.md_tls = (char*)tls_base;
if (td == curthread && cpuinfo.userlocal_reg == true) {
mips_wr_userlocal((unsigned long)tls_base +
td->td_md.md_tls_tcb_offset);
}
return (0);
}
int
cpu_set_user_tls(struct thread *td, void *tls_base)
{
struct pcb *pcb;
if ((u_int64_t)tls_base >= VM_MAXUSER_ADDRESS)
return (EINVAL);
pcb = td->td_pcb;
set_pcb_flags(pcb, PCB_FULL_IRET);
#ifdef COMPAT_FREEBSD32
if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) {
pcb->pcb_gsbase = (register_t)tls_base;
return (0);
}
#endif
pcb->pcb_fsbase = (register_t)tls_base;
return (0);
}
int
dtrace_getustackdepth(void)
{
proc_t *p = curproc;
struct trapframe *tf;
uintptr_t pc, sp;
int n = 0;
if (p == NULL || (tf = curthread->td_frame) == NULL)
return (0);
if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT))
return (-1);
pc = tf->srr0;
sp = tf->fixreg[1];
if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) {
/*
* In an entry probe. The frame pointer has not yet been
* pushed (that happens in the function prologue). The
* best approach is to add the current pc as a missing top
* of stack and back the pc up to the caller, which is stored
* at the current stack pointer address since the call
* instruction puts it there right before the branch.
*/
if (SV_PROC_FLAG(p, SV_ILP32)) {
pc = dtrace_fuword32((void *) sp);
}
else
pc = dtrace_fuword64((void *) sp);
n++;
}
n += dtrace_getustack_common(NULL, 0, pc, sp);
return (n);
}
void
dtrace_getufpstack(uint64_t *pcstack, uint64_t *fpstack, int pcstack_limit)
{
proc_t *p = curproc;
struct trapframe *tf;
uintptr_t pc, sp;
volatile uint16_t *flags =
(volatile uint16_t *)&cpu_core[curcpu].cpuc_dtrace_flags;
#ifdef notyet /* XXX signal stack */
uintptr_t oldcontext;
size_t s1, s2;
#endif
if (*flags & CPU_DTRACE_FAULT)
return;
if (pcstack_limit <= 0)
return;
/*
* If there's no user context we still need to zero the stack.
*/
if (p == NULL || (tf = curthread->td_frame) == NULL)
goto zero;
*pcstack++ = (uint64_t)p->p_pid;
pcstack_limit--;
if (pcstack_limit <= 0)
return;
pc = tf->srr0;
sp = tf->fixreg[1];
#ifdef notyet /* XXX signal stack */
oldcontext = lwp->lwp_oldcontext;
s1 = sizeof (struct xframe) + 2 * sizeof (long);
s2 = s1 + sizeof (siginfo_t);
#endif
if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_ENTRY)) {
*pcstack++ = (uint64_t)pc;
*fpstack++ = 0;
pcstack_limit--;
if (pcstack_limit <= 0)
return;
if (SV_PROC_FLAG(p, SV_ILP32)) {
pc = dtrace_fuword32((void *)sp);
}
else {
pc = dtrace_fuword64((void *)sp);
}
}
while (pc != 0) {
*pcstack++ = (uint64_t)pc;
*fpstack++ = sp;
pcstack_limit--;
if (pcstack_limit <= 0)
break;
if (sp == 0)
break;
#ifdef notyet /* XXX signal stack */
if (oldcontext == sp + s1 || oldcontext == sp + s2) {
ucontext_t *ucp = (ucontext_t *)oldcontext;
greg_t *gregs = ucp->uc_mcontext.gregs;
sp = dtrace_fulword(&gregs[REG_FP]);
pc = dtrace_fulword(&gregs[REG_PC]);
oldcontext = dtrace_fulword(&ucp->uc_link);
} else
#endif /* XXX */
{
if (SV_PROC_FLAG(p, SV_ILP32)) {
pc = dtrace_fuword32((void *)(sp + RETURN_OFFSET));
sp = dtrace_fuword32((void *)sp);
}
else {
pc = dtrace_fuword64((void *)(sp + RETURN_OFFSET64));
sp = dtrace_fuword64((void *)sp);
}
}
/*
* This is totally bogus: if we faulted, we're going to clear
* the fault and break. This is to deal with the apparently
* broken Java stacks on x86.
*/
if (*flags & CPU_DTRACE_FAULT) {
*flags &= ~CPU_DTRACE_FAULT;
break;
}
}
zero:
while (pcstack_limit-- > 0)
*pcstack++ = 0;
}
/*
* In-kernel implementation of execve(). All arguments are assumed to be
* userspace pointers from the passed thread.
*/
static int
do_execve(struct thread *td, struct image_args *args, struct mac *mac_p)
{
struct proc *p = td->td_proc;
struct nameidata nd;
struct ucred *oldcred;
struct uidinfo *euip = NULL;
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 = NULL, *newsigacts = NULL;
#ifdef KTRACE
struct vnode *tracevp = NULL;
struct ucred *tracecred = NULL;
#endif
struct vnode *oldtextvp = NULL, *newtextvp;
int credential_changing;
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)";
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
*/
bzero(imgp, sizeof(*imgp));
imgp->proc = p;
imgp->attr = &attr;
imgp->args = args;
oldcred = p->p_ucred;
#ifdef MAC
error = mac_execve_enter(imgp, mac_p);
if (error)
goto exec_fail;
#endif
/*
* Translate the file name. namei() returns a vnode pointer
* in ni_vp among 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
| AUDITVNODE1, UIO_SYSSPACE, args->fname, td);
}
SDT_PROBE1(proc, , , exec, args->fname);
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;
newtextvp = nd.ni_vp;
imgp->vp = newtextvp;
} else {
AUDIT_ARG_FD(args->fd);
/*
* Descriptors opened only with O_EXEC or O_RDONLY are allowed.
*/
error = fgetvp_exec(td, args->fd, &cap_fexecve_rights, &newtextvp);
if (error)
goto exec_fail;
vn_lock(newtextvp, LK_EXCLUSIVE | LK_RETRY);
AUDIT_ARG_VNODE1(newtextvp);
imgp->vp = newtextvp;
}
/*
* 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 = VOP_IS_TEXT(imgp->vp);
VOP_SET_TEXT(imgp->vp);
error = exec_map_first_page(imgp);
if (error)
goto exec_fail_dealloc;
imgp->proc->p_osrel = 0;
imgp->proc->p_fctl0 = 0;
/*
* Implement image setuid/setgid.
*
* Determine new credentials before attempting image activators
* so that it can be used by process_exec handlers to determine
* credential/setid changes.
*
* Don't honor setuid/setgid if the filesystem prohibits it or if
* the process is being traced.
*
* We disable setuid/setgid/etc in capability 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
/* Don't inherit PROC_PDEATHSIG_CTL value if setuid/setgid. */
if (credential_changing)
imgp->proc->p_pdeathsig = 0;
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) {
imgp->credential_setid = true;
VOP_UNLOCK(imgp->vp, 0);
imgp->newcred = crdup(oldcred);
if (attr.va_mode & S_ISUID) {
euip = uifind(attr.va_uid);
change_euid(imgp->newcred, euip);
}
vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
if (attr.va_mode & S_ISGID)
change_egid(imgp->newcred, attr.va_gid);
/*
* 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(imgp->newcred, imgp->newcred->cr_uid);
change_svgid(imgp->newcred, imgp->newcred->cr_gid);
} else {
/*
* 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) {
VOP_UNLOCK(imgp->vp, 0);
imgp->newcred = crdup(oldcred);
vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
change_svuid(imgp->newcred, imgp->newcred->cr_uid);
change_svgid(imgp->newcred, imgp->newcred->cr_gid);
}
}
/* The new credentials are installed into the process later. */
/*
* Do the best to calculate the full path to the image file.
*/
if (args->fname != NULL && args->fname[0] == '/')
imgp->execpath = args->fname;
else {
VOP_UNLOCK(imgp->vp, 0);
if (vn_fullpath(td, imgp->vp, &imgp->execpath,
&imgp->freepath) != 0)
imgp->execpath = args->fname;
vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY);
}
/*
* 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)
VOP_UNSET_TEXT(imgp->vp);
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.
*/
VOP_UNSET_TEXT(imgp->vp);
/* free name buffer and old vnode */
if (args->fname != NULL)
NDFREE(&nd, NDF_ONLY_PNBUF);
#ifdef MAC
mac_execve_interpreter_enter(newtextvp, &interpvplabel);
#endif
if (imgp->opened) {
VOP_CLOSE(newtextvp, FREAD, td->td_ucred, td);
imgp->opened = 0;
}
vput(newtextvp);
vm_object_deallocate(imgp->object);
imgp->object = NULL;
imgp->credential_setid = false;
if (imgp->newcred != NULL) {
crfree(imgp->newcred);
imgp->newcred = NULL;
}
imgp->execpath = NULL;
free(imgp->freepath, M_TEMP);
imgp->freepath = NULL;
/* set new name to that of the interpreter */
NDINIT(&nd, LOOKUP, LOCKLEAF | FOLLOW | SAVENAME,
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);
if (disallow_high_osrel &&
P_OSREL_MAJOR(p->p_osrel) > P_OSREL_MAJOR(__FreeBSD_version)) {
error = ENOEXEC;
uprintf("Osrel %d for image %s too high\n", p->p_osrel,
imgp->execpath != NULL ? imgp->execpath : "<unresolved>");
vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
goto exec_fail_dealloc;
}
/* ABI enforces the use of Capsicum. Switch into capabilities mode. */
if (SV_PROC_FLAG(p, SV_CAPSICUM))
sys_cap_enter(td, NULL);
/*
* Copy out strings (args and env) and initialize stack base.
*/
stack_base = (*p->p_sysent->sv_copyout_strings)(imgp);
/*
* Stack setup.
*/
error = (*p->p_sysent->sv_fixup)(&stack_base, imgp);
if (error != 0) {
vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
goto exec_fail_dealloc;
}
if (args->fdp != NULL) {
/* Install a brand new file descriptor table. */
fdinstall_remapped(td, args->fdp);
args->fdp = NULL;
} else {
/*
* Keep on using the existing file descriptor table. For
* security and other reasons, the file descriptor table
* cannot be shared after an exec.
*/
fdunshare(td);
/* close files on exec */
fdcloseexec(td);
}
/*
* Malloc things before we need locks.
*/
i = exec_args_get_begin_envv(imgp->args) - 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);
}
/*
* 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.
*/
if (sigacts_shared(p->p_sigacts)) {
oldsigacts = p->p_sigacts;
newsigacts = sigacts_alloc();
sigacts_copy(newsigacts, oldsigacts);
}
vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
PROC_LOCK(p);
if (oldsigacts)
p->p_sigacts = newsigacts;
/* 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(newtextvp, 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_flag2 & P2_NOTRACE_EXEC) == 0)
p->p_flag2 &= ~P2_NOTRACE;
if (p->p_flag & P_PPWAIT) {
p->p_flag &= ~(P_PPWAIT | P_PPTRACE);
cv_broadcast(&p->p_pwait);
/* STOPs are no longer ignored, arrange for AST */
signotify(td);
}
/*
* Implement image setuid/setgid installation.
*/
if (imgp->credential_setid) {
/*
* 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 (p->p_tracecred != NULL &&
priv_check_cred(p->p_tracecred, PRIV_DEBUG_DIFFCRED))
ktrprocexec(p, &tracecred, &tracevp);
#endif
/*
* Close any file descriptors 0..2 that reference procfs,
* then make sure file descriptors 0..2 are in use.
*
* Both fdsetugidsafety() and fdcheckstd() may call functions
* taking sleepable locks, so temporarily drop our locks.
*/
PROC_UNLOCK(p);
VOP_UNLOCK(imgp->vp, 0);
fdsetugidsafety(td);
error = fdcheckstd(td);
vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
if (error != 0)
goto exec_fail_dealloc;
PROC_LOCK(p);
#ifdef MAC
if (will_transition) {
mac_vnode_execve_transition(oldcred, imgp->newcred,
imgp->vp, interpvplabel, imgp);
}
#endif
} else {
if (oldcred->cr_uid == oldcred->cr_ruid &&
oldcred->cr_gid == oldcred->cr_rgid)
p->p_flag &= ~P_SUGID;
}
/*
* Set the new credentials.
*/
if (imgp->newcred != NULL) {
proc_set_cred(p, imgp->newcred);
crfree(oldcred);
oldcred = NULL;
}
/*
* Store the vp for use in procfs. This vnode was referenced by namei
* or fgetvp_exec.
*/
oldtextvp = p->p_textvp;
p->p_textvp = newtextvp;
#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;
/*
* Free any previous argument cache and replace it with
* the new argument cache, if any.
*/
oldargs = p->p_args;
p->p_args = newargs;
newargs = NULL;
PROC_UNLOCK(p);
#ifdef HWPMC_HOOKS
/*
* Check if system-wide sampling is in effect or if the
* current process is using PMCs. If so, do exec() time
* processing. This processing needs to happen AFTER the
* P_INEXEC flag is cleared.
*/
if (PMC_SYSTEM_SAMPLING_ACTIVE() || PMC_PROC_IS_USING_PMCS(p)) {
VOP_UNLOCK(imgp->vp, 0);
pe.pm_credentialschanged = credential_changing;
pe.pm_entryaddr = imgp->entry_addr;
PMC_CALL_HOOK_X(td, PMC_FN_PROCESS_EXEC, (void *) &pe);
vn_lock(imgp->vp, LK_SHARED | LK_RETRY);
}
#endif
/* Set values passed into the program in registers. */
(*p->p_sysent->sv_setregs)(td, imgp, (u_long)(uintptr_t)stack_base);
vfs_mark_atime(imgp->vp, td->td_ucred);
SDT_PROBE1(proc, , , exec__success, args->fname);
exec_fail_dealloc:
if (imgp->firstpage != NULL)
exec_unmap_first_page(imgp);
if (imgp->vp != NULL) {
if (args->fname)
NDFREE(&nd, NDF_ONLY_PNBUF);
if (imgp->opened)
VOP_CLOSE(imgp->vp, FREAD, td->td_ucred, td);
if (error != 0)
vput(imgp->vp);
else
VOP_UNLOCK(imgp->vp, 0);
}
if (imgp->object != NULL)
vm_object_deallocate(imgp->object);
free(imgp->freepath, M_TEMP);
if (error == 0) {
if (p->p_ptevents & PTRACE_EXEC) {
PROC_LOCK(p);
if (p->p_ptevents & PTRACE_EXEC)
td->td_dbgflags |= TDB_EXEC;
PROC_UNLOCK(p);
}
/*
* Stop the process here if its stop event mask has
* the S_EXEC bit set.
*/
STOPEVENT(p, S_EXEC, 0);
} else {
exec_fail:
/* we're done here, clear P_INEXEC */
PROC_LOCK(p);
p->p_flag &= ~P_INEXEC;
PROC_UNLOCK(p);
SDT_PROBE1(proc, , , exec__failure, error);
}
if (imgp->newcred != NULL && oldcred != NULL)
crfree(imgp->newcred);
#ifdef MAC
mac_execve_exit(imgp);
mac_execve_interpreter_exit(interpvplabel);
#endif
exec_free_args(args);
/*
* Handle deferred decrement of ref counts.
*/
if (oldtextvp != NULL)
vrele(oldtextvp);
#ifdef KTRACE
if (tracevp != NULL)
vrele(tracevp);
if (tracecred != NULL)
crfree(tracecred);
#endif
pargs_drop(oldargs);
pargs_drop(newargs);
if (oldsigacts != NULL)
sigacts_free(oldsigacts);
if (euip != NULL)
uifree(euip);
if (error && imgp->vmspace_destroyed) {
/* sorry, no more process anymore. exit gracefully */
exit1(td, 0, SIGABRT);
/* NOT REACHED */
}
#ifdef KTRACE
if (error == 0)
ktrprocctor(p);
#endif
/*
* We don't want cpu_set_syscall_retval() to overwrite any of
* the register values put in place by exec_setregs().
* Implementations of cpu_set_syscall_retval() will leave
* registers unmodified when returning EJUSTRETURN.
*/
return (error == 0 ? EJUSTRETURN : error);
}
/*
* The map entries can *almost* be read with programs like cat. However,
* large maps need special programs to read. It is not easy to implement
* a program that can sense the required size of the buffer, and then
* subsequently do a read with the appropriate size. This operation cannot
* be atomic. The best that we can do is to allow the program to do a read
* with an arbitrarily large buffer, and return as much as we can. We can
* return an error code if the buffer is too small (EFBIG), then the program
* can try a bigger buffer.
*/
int
procfs_doprocmap(PFS_FILL_ARGS)
{
struct vmspace *vm;
vm_map_t map;
vm_map_entry_t entry, tmp_entry;
struct vnode *vp;
char *fullpath, *freepath;
struct ucred *cred;
int error;
unsigned int last_timestamp;
#ifdef COMPAT_FREEBSD32
int wrap32 = 0;
#endif
PROC_LOCK(p);
error = p_candebug(td, p);
PROC_UNLOCK(p);
if (error)
return (error);
if (uio->uio_rw != UIO_READ)
return (EOPNOTSUPP);
#ifdef COMPAT_FREEBSD32
if (SV_CURPROC_FLAG(SV_ILP32)) {
if (!(SV_PROC_FLAG(p, SV_ILP32)))
return (EOPNOTSUPP);
wrap32 = 1;
}
#endif
vm = vmspace_acquire_ref(p);
if (vm == NULL)
return (ESRCH);
map = &vm->vm_map;
vm_map_lock_read(map);
for (entry = map->header.next; entry != &map->header;
entry = entry->next) {
vm_object_t obj, tobj, lobj;
int ref_count, shadow_count, flags;
vm_offset_t e_start, e_end, addr;
int resident, privateresident;
char *type;
vm_eflags_t e_eflags;
vm_prot_t e_prot;
if (entry->eflags & MAP_ENTRY_IS_SUB_MAP)
continue;
e_eflags = entry->eflags;
e_prot = entry->protection;
e_start = entry->start;
e_end = entry->end;
privateresident = 0;
obj = entry->object.vm_object;
if (obj != NULL) {
VM_OBJECT_RLOCK(obj);
if (obj->shadow_count == 1)
privateresident = obj->resident_page_count;
}
cred = (entry->cred) ? entry->cred : (obj ? obj->cred : NULL);
resident = 0;
addr = entry->start;
while (addr < entry->end) {
if (pmap_extract(map->pmap, addr))
resident++;
addr += PAGE_SIZE;
}
for (lobj = tobj = obj; tobj; tobj = tobj->backing_object) {
if (tobj != obj)
VM_OBJECT_RLOCK(tobj);
if (lobj != obj)
VM_OBJECT_RUNLOCK(lobj);
lobj = tobj;
}
last_timestamp = map->timestamp;
vm_map_unlock_read(map);
freepath = NULL;
fullpath = "-";
if (lobj) {
vp = NULL;
switch (lobj->type) {
default:
case OBJT_DEFAULT:
type = "default";
break;
case OBJT_VNODE:
type = "vnode";
vp = lobj->handle;
vref(vp);
break;
case OBJT_SWAP:
if ((lobj->flags & OBJ_TMPFS_NODE) != 0) {
type = "vnode";
if ((lobj->flags & OBJ_TMPFS) != 0) {
vp = lobj->un_pager.swp.swp_tmpfs;
vref(vp);
}
} else {
type = "swap";
}
break;
case OBJT_SG:
case OBJT_DEVICE:
type = "device";
break;
}
if (lobj != obj)
VM_OBJECT_RUNLOCK(lobj);
flags = obj->flags;
ref_count = obj->ref_count;
shadow_count = obj->shadow_count;
VM_OBJECT_RUNLOCK(obj);
if (vp != NULL) {
vn_fullpath(td, vp, &fullpath, &freepath);
vrele(vp);
}
} else {
type = "none";
flags = 0;
ref_count = 0;
shadow_count = 0;
}
/*
* format:
* start, end, resident, private resident, cow, access, type,
* charged, charged uid.
*/
error = sbuf_printf(sb,
"0x%lx 0x%lx %d %d %p %s%s%s %d %d 0x%x %s %s %s %s %s %d\n",
(u_long)e_start, (u_long)e_end,
resident, privateresident,
#ifdef COMPAT_FREEBSD32
wrap32 ? NULL : obj, /* Hide 64 bit value */
#else
obj,
#endif
(e_prot & VM_PROT_READ)?"r":"-",
(e_prot & VM_PROT_WRITE)?"w":"-",
(e_prot & VM_PROT_EXECUTE)?"x":"-",
ref_count, shadow_count, flags,
(e_eflags & MAP_ENTRY_COW)?"COW":"NCOW",
(e_eflags & MAP_ENTRY_NEEDS_COPY)?"NC":"NNC",
type, fullpath,
cred ? "CH":"NCH", cred ? cred->cr_ruid : -1);
if (freepath != NULL)
free(freepath, M_TEMP);
vm_map_lock_read(map);
if (error == -1) {
error = 0;
break;
}
if (last_timestamp != map->timestamp) {
/*
* Look again for the entry because the map was
* modified while it was unlocked. Specifically,
* the entry may have been clipped, merged, or deleted.
*/
vm_map_lookup_entry(map, e_end - 1, &tmp_entry);
entry = tmp_entry;
}
}
vm_map_unlock_read(map);
vmspace_free(vm);
return (error);
}
void
cpu_set_syscall_retval(struct thread *td, int error)
{
struct trapframe *locr0 = td->td_frame;
unsigned int code;
int quad_syscall;
code = locr0->v0;
quad_syscall = 0;
#if defined(__mips_n32) || defined(__mips_n64)
#ifdef COMPAT_FREEBSD32
if (code == SYS___syscall && SV_PROC_FLAG(td->td_proc, SV_ILP32))
quad_syscall = 1;
#endif
#else
if (code == SYS___syscall)
quad_syscall = 1;
#endif
if (code == SYS_syscall)
code = locr0->a0;
else if (code == SYS___syscall) {
if (quad_syscall)
code = _QUAD_LOWWORD ? locr0->a1 : locr0->a0;
else
code = locr0->a0;
}
switch (error) {
case 0:
if (quad_syscall && code != SYS_lseek) {
/*
* System call invoked through the
* SYS___syscall interface but the
* return value is really just 32
* bits.
*/
locr0->v0 = td->td_retval[0];
if (_QUAD_LOWWORD)
locr0->v1 = td->td_retval[0];
locr0->a3 = 0;
} else {
locr0->v0 = td->td_retval[0];
locr0->v1 = td->td_retval[1];
locr0->a3 = 0;
}
break;
case ERESTART:
locr0->pc = td->td_pcb->pcb_tpc;
break;
case EJUSTRETURN:
break; /* nothing to do */
default:
if (quad_syscall && code != SYS_lseek) {
locr0->v0 = error;
if (_QUAD_LOWWORD)
locr0->v1 = error;
locr0->a3 = 1;
} else {
locr0->v0 = error;
locr0->a3 = 1;
}
}
}
