void
unix_syscall_return(int error)
{
thread_act_t thread;
volatile int *rval;
struct i386_saved_state *regs;
struct proc *p;
struct proc *current_proc();
unsigned short code;
vm_offset_t params;
struct sysent *callp;
extern int nsysent;
thread = current_act();
rval = (int *)get_bsduthreadrval(thread);
p = current_proc();
regs = USER_REGS(thread);
/* reconstruct code for tracing before blasting eax */
code = regs->eax;
params = (vm_offset_t) ((caddr_t)regs->uesp + sizeof (int));
callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
if (callp == sysent) {
code = fuword(params);
}
if (error == ERESTART) {
regs->eip -= 7;
}
else if (error != EJUSTRETURN) {
if (error) {
regs->eax = error;
regs->efl |= EFL_CF; /* carry bit */
} else { /* (not error) */
regs->eax = rval[0];
regs->edx = rval[1];
regs->efl &= ~EFL_CF;
}
}
ktrsysret(p, code, error, rval[0], callp->sy_funnel);
KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_END,
error, rval[0], rval[1], 0, 0);
if (callp->sy_funnel != NO_FUNNEL)
(void) thread_funnel_set(current_thread()->funnel_lock, FALSE);
thread_exception_return();
/* NOTREACHED */
}
static int
sd_callback3(proc_t p, void * args)
{
struct sd_iterargs * sd = (struct sd_iterargs *)args;
vfs_context_t ctx = vfs_context_current();
int setsdstate = sd->setsdstate;
proc_lock(p);
p->p_shutdownstate = setsdstate;
if (p->p_stat != SZOMB) {
/*
* NOTE: following code ignores sig_lock and plays
* with exit_thread correctly. This is OK unless we
* are a multiprocessor, in which case I do not
* understand the sig_lock. This needs to be fixed.
* XXX
*/
if (p->exit_thread) { /* someone already doing it */
proc_unlock(p);
/* give him a chance */
thread_block(THREAD_CONTINUE_NULL);
} else {
p->exit_thread = current_thread();
printf(".");
sd_log(ctx, "%s[%d] had to be forced closed with exit1().\n", p->p_comm, p->p_pid);
proc_unlock(p);
KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_FRCEXIT) | DBG_FUNC_NONE,
p->p_pid, 0, 1, 0, 0);
sd->activecount++;
exit1(p, 1, (int *)NULL);
}
} else {
proc_unlock(p);
}
return PROC_RETURNED;
}
/*
* Function: unix_syscall
*
* Inputs: regs - pointer to i386 save area
*
* Outputs: none
*/
void
unix_syscall(x86_saved_state_t *state)
{
thread_t thread;
void *vt;
unsigned int code;
struct sysent *callp;
int error;
vm_offset_t params;
struct proc *p;
struct uthread *uthread;
x86_saved_state32_t *regs;
boolean_t is_vfork;
assert(is_saved_state32(state));
regs = saved_state32(state);
#if DEBUG
if (regs->eax == 0x800)
thread_exception_return();
#endif
thread = current_thread();
uthread = get_bsdthread_info(thread);
/* Get the approriate proc; may be different from task's for vfork() */
is_vfork = uthread->uu_flag & UT_VFORK;
if (__improbable(is_vfork != 0))
p = current_proc();
else
p = (struct proc *)get_bsdtask_info(current_task());
/* Verify that we are not being called from a task without a proc */
if (__improbable(p == NULL)) {
regs->eax = EPERM;
regs->efl |= EFL_CF;
task_terminate_internal(current_task());
thread_exception_return();
/* NOTREACHED */
}
code = regs->eax & I386_SYSCALL_NUMBER_MASK;
DEBUG_KPRINT_SYSCALL_UNIX("unix_syscall: code=%d(%s) eip=%u\n",
code, syscallnames[code >= NUM_SYSENT ? 63 : code], (uint32_t)regs->eip);
params = (vm_offset_t) (regs->uesp + sizeof (int));
regs->efl &= ~(EFL_CF);
callp = (code >= NUM_SYSENT) ? &sysent[63] : &sysent[code];
if (__improbable(callp == sysent)) {
code = fuword(params);
params += sizeof(int);
callp = (code >= NUM_SYSENT) ? &sysent[63] : &sysent[code];
}
vt = (void *)uthread->uu_arg;
if (callp->sy_arg_bytes != 0) {
#if CONFIG_REQUIRES_U32_MUNGING
sy_munge_t *mungerp;
#else
#error U32 syscalls on x86_64 kernel requires munging
#endif
uint32_t nargs;
assert((unsigned) callp->sy_arg_bytes <= sizeof (uthread->uu_arg));
nargs = callp->sy_arg_bytes;
error = copyin((user_addr_t) params, (char *) vt, nargs);
if (error) {
regs->eax = error;
regs->efl |= EFL_CF;
thread_exception_return();
/* NOTREACHED */
}
if (__probable(code != 180)) {
int *ip = (int *)vt;
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_START,
*ip, *(ip+1), *(ip+2), *(ip+3), 0);
}
#if CONFIG_REQUIRES_U32_MUNGING
mungerp = callp->sy_arg_munge32;
if (mungerp != NULL)
(*mungerp)(vt);
#endif
} else
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_START,
0, 0, 0, 0, 0);
/*
* Delayed binding of thread credential to process credential, if we
* are not running with an explicitly set thread credential.
*/
kauth_cred_uthread_update(uthread, p);
uthread->uu_rval[0] = 0;
uthread->uu_rval[1] = 0;
uthread->uu_flag |= UT_NOTCANCELPT;
uthread->syscall_code = code;
#ifdef JOE_DEBUG
uthread->uu_iocount = 0;
uthread->uu_vpindex = 0;
#endif
AUDIT_SYSCALL_ENTER(code, p, uthread);
error = (*(callp->sy_call))((void *) p, (void *) vt, &(uthread->uu_rval[0]));
AUDIT_SYSCALL_EXIT(code, p, uthread, error);
#ifdef JOE_DEBUG
if (uthread->uu_iocount)
printf("system call returned with uu_iocount != 0\n");
#endif
#if CONFIG_DTRACE
uthread->t_dtrace_errno = error;
#endif /* CONFIG_DTRACE */
if (__improbable(error == ERESTART)) {
/*
* Move the user's pc back to repeat the syscall:
* 5 bytes for a sysenter, or 2 for an int 8x.
* The SYSENTER_TF_CS covers single-stepping over a sysenter
* - see debug trap handler in idt.s/idt64.s
*/
pal_syscall_restart(thread, state);
}
else if (error != EJUSTRETURN) {
if (__improbable(error)) {
regs->eax = error;
regs->efl |= EFL_CF; /* carry bit */
} else { /* (not error) */
/*
* We split retval across two registers, in case the
* syscall had a 64-bit return value, in which case
* eax/edx matches the function call ABI.
*/
regs->eax = uthread->uu_rval[0];
regs->edx = uthread->uu_rval[1];
}
}
DEBUG_KPRINT_SYSCALL_UNIX(
"unix_syscall: error=%d retval=(%u,%u)\n",
error, regs->eax, regs->edx);
uthread->uu_flag &= ~UT_NOTCANCELPT;
if (__improbable(uthread->uu_lowpri_window)) {
/*
* task is marked as a low priority I/O type
* and the I/O we issued while in this system call
* collided with normal I/O operations... we'll
* delay in order to mitigate the impact of this
* task on the normal operation of the system
*/
throttle_lowpri_io(1);
}
if (__probable(code != 180))
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_END,
error, uthread->uu_rval[0], uthread->uu_rval[1], p->p_pid, 0);
if (__improbable(!is_vfork && callp->sy_call == (sy_call_t *)execve && !error)) {
pal_execve_return(thread);
}
thread_exception_return();
/* NOTREACHED */
}
void
unix_syscall_return(int error)
{
thread_t thread;
struct uthread *uthread;
struct proc *p;
unsigned int code;
struct sysent *callp;
thread = current_thread();
uthread = get_bsdthread_info(thread);
pal_register_cache_state(thread, DIRTY);
p = current_proc();
if (proc_is64bit(p)) {
x86_saved_state64_t *regs;
regs = saved_state64(find_user_regs(thread));
code = uthread->syscall_code;
callp = (code >= NUM_SYSENT) ? &sysent[63] : &sysent[code];
#if CONFIG_DTRACE
if (callp->sy_call == dtrace_systrace_syscall)
dtrace_systrace_syscall_return( code, error, uthread->uu_rval );
#endif /* CONFIG_DTRACE */
AUDIT_SYSCALL_EXIT(code, p, uthread, error);
if (error == ERESTART) {
/*
* repeat the syscall
*/
pal_syscall_restart( thread, find_user_regs(thread) );
}
else if (error != EJUSTRETURN) {
if (error) {
regs->rax = error;
regs->isf.rflags |= EFL_CF; /* carry bit */
} else { /* (not error) */
switch (callp->sy_return_type) {
case _SYSCALL_RET_INT_T:
regs->rax = uthread->uu_rval[0];
regs->rdx = uthread->uu_rval[1];
break;
case _SYSCALL_RET_UINT_T:
regs->rax = ((u_int)uthread->uu_rval[0]);
regs->rdx = ((u_int)uthread->uu_rval[1]);
break;
case _SYSCALL_RET_OFF_T:
case _SYSCALL_RET_ADDR_T:
case _SYSCALL_RET_SIZE_T:
case _SYSCALL_RET_SSIZE_T:
case _SYSCALL_RET_UINT64_T:
regs->rax = *((uint64_t *)(&uthread->uu_rval[0]));
regs->rdx = 0;
break;
case _SYSCALL_RET_NONE:
break;
default:
panic("unix_syscall: unknown return type");
break;
}
regs->isf.rflags &= ~EFL_CF;
}
}
DEBUG_KPRINT_SYSCALL_UNIX(
"unix_syscall_return: error=%d retval=(%llu,%llu)\n",
error, regs->rax, regs->rdx);
} else {
x86_saved_state32_t *regs;
regs = saved_state32(find_user_regs(thread));
regs->efl &= ~(EFL_CF);
code = uthread->syscall_code;
callp = (code >= NUM_SYSENT) ? &sysent[63] : &sysent[code];
#if CONFIG_DTRACE
if (callp->sy_call == dtrace_systrace_syscall)
dtrace_systrace_syscall_return( code, error, uthread->uu_rval );
#endif /* CONFIG_DTRACE */
AUDIT_SYSCALL_EXIT(code, p, uthread, error);
if (error == ERESTART) {
pal_syscall_restart( thread, find_user_regs(thread) );
}
else if (error != EJUSTRETURN) {
if (error) {
regs->eax = error;
regs->efl |= EFL_CF; /* carry bit */
} else { /* (not error) */
regs->eax = uthread->uu_rval[0];
regs->edx = uthread->uu_rval[1];
}
}
DEBUG_KPRINT_SYSCALL_UNIX(
"unix_syscall_return: error=%d retval=(%u,%u)\n",
error, regs->eax, regs->edx);
}
uthread->uu_flag &= ~UT_NOTCANCELPT;
if (uthread->uu_lowpri_window) {
/*
* task is marked as a low priority I/O type
* and the I/O we issued while in this system call
* collided with normal I/O operations... we'll
* delay in order to mitigate the impact of this
* task on the normal operation of the system
*/
throttle_lowpri_io(1);
}
if (code != 180)
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_END,
error, uthread->uu_rval[0], uthread->uu_rval[1], p->p_pid, 0);
thread_exception_return();
/* NOTREACHED */
}
void
unix_syscall64(x86_saved_state_t *state)
{
thread_t thread;
void *vt;
unsigned int code;
struct sysent *callp;
int args_in_regs;
boolean_t args_start_at_rdi;
int error;
struct proc *p;
struct uthread *uthread;
x86_saved_state64_t *regs;
assert(is_saved_state64(state));
regs = saved_state64(state);
#if DEBUG
if (regs->rax == 0x2000800)
thread_exception_return();
#endif
thread = current_thread();
uthread = get_bsdthread_info(thread);
/* Get the approriate proc; may be different from task's for vfork() */
if (__probable(!(uthread->uu_flag & UT_VFORK)))
p = (struct proc *)get_bsdtask_info(current_task());
else
p = current_proc();
/* Verify that we are not being called from a task without a proc */
if (__improbable(p == NULL)) {
regs->rax = EPERM;
regs->isf.rflags |= EFL_CF;
task_terminate_internal(current_task());
thread_exception_return();
/* NOTREACHED */
}
code = regs->rax & SYSCALL_NUMBER_MASK;
DEBUG_KPRINT_SYSCALL_UNIX(
"unix_syscall64: code=%d(%s) rip=%llx\n",
code, syscallnames[code >= NUM_SYSENT ? 63 : code], regs->isf.rip);
callp = (code >= NUM_SYSENT) ? &sysent[63] : &sysent[code];
vt = (void *)uthread->uu_arg;
if (__improbable(callp == sysent)) {
/*
* indirect system call... system call number
* passed as 'arg0'
*/
code = regs->rdi;
callp = (code >= NUM_SYSENT) ? &sysent[63] : &sysent[code];
args_start_at_rdi = FALSE;
args_in_regs = 5;
} else {
args_start_at_rdi = TRUE;
args_in_regs = 6;
}
if (callp->sy_narg != 0) {
assert(callp->sy_narg <= 8); /* size of uu_arg */
args_in_regs = MIN(args_in_regs, callp->sy_narg);
memcpy(vt, args_start_at_rdi ? ®s->rdi : ®s->rsi, args_in_regs * sizeof(syscall_arg_t));
if (code != 180) {
uint64_t *ip = (uint64_t *)vt;
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_START,
(int)(*ip), (int)(*(ip+1)), (int)(*(ip+2)), (int)(*(ip+3)), 0);
}
if (__improbable(callp->sy_narg > args_in_regs)) {
int copyin_count;
copyin_count = (callp->sy_narg - args_in_regs) * sizeof(syscall_arg_t);
error = copyin((user_addr_t)(regs->isf.rsp + sizeof(user_addr_t)), (char *)&uthread->uu_arg[args_in_regs], copyin_count);
if (error) {
regs->rax = error;
regs->isf.rflags |= EFL_CF;
thread_exception_return();
/* NOTREACHED */
}
}
} else
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_START,
0, 0, 0, 0, 0);
/*
* Delayed binding of thread credential to process credential, if we
* are not running with an explicitly set thread credential.
*/
kauth_cred_uthread_update(uthread, p);
uthread->uu_rval[0] = 0;
uthread->uu_rval[1] = 0;
uthread->uu_flag |= UT_NOTCANCELPT;
uthread->syscall_code = code;
#ifdef JOE_DEBUG
uthread->uu_iocount = 0;
uthread->uu_vpindex = 0;
#endif
AUDIT_SYSCALL_ENTER(code, p, uthread);
error = (*(callp->sy_call))((void *) p, vt, &(uthread->uu_rval[0]));
AUDIT_SYSCALL_EXIT(code, p, uthread, error);
#ifdef JOE_DEBUG
if (uthread->uu_iocount)
printf("system call returned with uu_iocount != 0\n");
#endif
#if CONFIG_DTRACE
uthread->t_dtrace_errno = error;
#endif /* CONFIG_DTRACE */
if (__improbable(error == ERESTART)) {
/*
* all system calls come through via the syscall instruction
* in 64 bit mode... its 2 bytes in length
* move the user's pc back to repeat the syscall:
*/
pal_syscall_restart( thread, state );
}
else if (error != EJUSTRETURN) {
if (__improbable(error)) {
regs->rax = error;
regs->isf.rflags |= EFL_CF; /* carry bit */
} else { /* (not error) */
switch (callp->sy_return_type) {
case _SYSCALL_RET_INT_T:
regs->rax = uthread->uu_rval[0];
regs->rdx = uthread->uu_rval[1];
break;
case _SYSCALL_RET_UINT_T:
regs->rax = ((u_int)uthread->uu_rval[0]);
regs->rdx = ((u_int)uthread->uu_rval[1]);
break;
case _SYSCALL_RET_OFF_T:
case _SYSCALL_RET_ADDR_T:
case _SYSCALL_RET_SIZE_T:
case _SYSCALL_RET_SSIZE_T:
case _SYSCALL_RET_UINT64_T:
regs->rax = *((uint64_t *)(&uthread->uu_rval[0]));
regs->rdx = 0;
break;
case _SYSCALL_RET_NONE:
break;
default:
panic("unix_syscall: unknown return type");
break;
}
regs->isf.rflags &= ~EFL_CF;
}
}
DEBUG_KPRINT_SYSCALL_UNIX(
"unix_syscall64: error=%d retval=(%llu,%llu)\n",
error, regs->rax, regs->rdx);
uthread->uu_flag &= ~UT_NOTCANCELPT;
if (__improbable(uthread->uu_lowpri_window)) {
/*
* task is marked as a low priority I/O type
* and the I/O we issued while in this system call
* collided with normal I/O operations... we'll
* delay in order to mitigate the impact of this
* task on the normal operation of the system
*/
throttle_lowpri_io(1);
}
if (__probable(code != 180))
KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE,
BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_END,
error, uthread->uu_rval[0], uthread->uu_rval[1], p->p_pid, 0);
thread_exception_return();
/* NOTREACHED */
}
int
msync_nocancel(__unused proc_t p, struct msync_nocancel_args *uap, __unused register_t *retval)
{
mach_vm_offset_t addr;
mach_vm_size_t size;
int flags;
vm_map_t user_map;
int rv;
vm_sync_t sync_flags=0;
addr = (mach_vm_offset_t) uap->addr;
size = (mach_vm_size_t)uap->len;
KERNEL_DEBUG_CONSTANT((BSDDBG_CODE(DBG_BSD_SC_EXTENDED_INFO, SYS_msync) | DBG_FUNC_NONE), (uint32_t)(addr >> 32), (uint32_t)(size >> 32), 0, 0, 0);
if (addr & PAGE_MASK_64) {
/* UNIX SPEC: user address is not page-aligned, return EINVAL */
return EINVAL;
}
if (size == 0) {
/*
* We cannot support this properly without maintaining
* list all mmaps done. Cannot use vm_map_entry as they could be
* split or coalesced by indepenedant actions. So instead of
* inaccurate results, lets just return error as invalid size
* specified
*/
return (EINVAL); /* XXX breaks posix apps */
}
flags = uap->flags;
/* disallow contradictory flags */
if ((flags & (MS_SYNC|MS_ASYNC)) == (MS_SYNC|MS_ASYNC))
return (EINVAL);
if (flags & MS_KILLPAGES)
sync_flags |= VM_SYNC_KILLPAGES;
if (flags & MS_DEACTIVATE)
sync_flags |= VM_SYNC_DEACTIVATE;
if (flags & MS_INVALIDATE)
sync_flags |= VM_SYNC_INVALIDATE;
if ( !(flags & (MS_KILLPAGES | MS_DEACTIVATE))) {
if (flags & MS_ASYNC)
sync_flags |= VM_SYNC_ASYNCHRONOUS;
else
sync_flags |= VM_SYNC_SYNCHRONOUS;
}
sync_flags |= VM_SYNC_CONTIGUOUS; /* complain if holes */
user_map = current_map();
rv = mach_vm_msync(user_map, addr, size, sync_flags);
switch (rv) {
case KERN_SUCCESS:
break;
case KERN_INVALID_ADDRESS: /* hole in region being sync'ed */
return (ENOMEM);
case KERN_FAILURE:
return (EIO);
default:
return (EINVAL);
}
return (0);
}
/*
* XXX Internally, we use VM_PROT_* somewhat interchangeably, but the correct
* XXX usage is PROT_* from an interface perspective. Thus the values of
* XXX VM_PROT_* and PROT_* need to correspond.
*/
int
mmap(proc_t p, struct mmap_args *uap, user_addr_t *retval)
{
/*
* Map in special device (must be SHARED) or file
*/
struct fileproc *fp;
register struct vnode *vp;
int flags;
int prot, file_prot;
int err=0;
vm_map_t user_map;
kern_return_t result;
mach_vm_offset_t user_addr;
mach_vm_size_t user_size;
vm_object_offset_t pageoff;
vm_object_offset_t file_pos;
int alloc_flags=0;
boolean_t docow;
vm_prot_t maxprot;
void *handle;
vm_pager_t pager;
int mapanon=0;
int fpref=0;
int error =0;
int fd = uap->fd;
user_addr = (mach_vm_offset_t)uap->addr;
user_size = (mach_vm_size_t) uap->len;
AUDIT_ARG(addr, user_addr);
AUDIT_ARG(len, user_size);
AUDIT_ARG(fd, uap->fd);
prot = (uap->prot & VM_PROT_ALL);
#if 3777787
/*
* Since the hardware currently does not support writing without
* read-before-write, or execution-without-read, if the request is
* for write or execute access, we must imply read access as well;
* otherwise programs expecting this to work will fail to operate.
*/
if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
prot |= VM_PROT_READ;
#endif /* radar 3777787 */
flags = uap->flags;
vp = NULLVP;
/*
* The vm code does not have prototypes & compiler doesn't do the'
* the right thing when you cast 64bit value and pass it in function
* call. So here it is.
*/
file_pos = (vm_object_offset_t)uap->pos;
/* make sure mapping fits into numeric range etc */
if (file_pos + user_size > (vm_object_offset_t)-PAGE_SIZE_64)
return (EINVAL);
/*
* Align the file position to a page boundary,
* and save its page offset component.
*/
pageoff = (file_pos & PAGE_MASK);
file_pos -= (vm_object_offset_t)pageoff;
/* Adjust size for rounding (on both ends). */
user_size += pageoff; /* low end... */
user_size = mach_vm_round_page(user_size); /* hi end */
/*
* Check for illegal addresses. Watch out for address wrap... Note
* that VM_*_ADDRESS are not constants due to casts (argh).
*/
if (flags & MAP_FIXED) {
/*
* The specified address must have the same remainder
* as the file offset taken modulo PAGE_SIZE, so it
* should be aligned after adjustment by pageoff.
*/
user_addr -= pageoff;
if (user_addr & PAGE_MASK)
return (EINVAL);
}
#ifdef notyet
/* DO not have apis to get this info, need to wait till then*/
/*
* XXX for non-fixed mappings where no hint is provided or
* the hint would fall in the potential heap space,
* place it after the end of the largest possible heap.
*
* There should really be a pmap call to determine a reasonable
* location.
*/
else if (addr < mach_vm_round_page(p->p_vmspace->vm_daddr + MAXDSIZ))
addr = mach_vm_round_page(p->p_vmspace->vm_daddr + MAXDSIZ);
#endif
alloc_flags = 0;
if (flags & MAP_ANON) {
/*
* Mapping blank space is trivial. Use positive fds as the alias
* value for memory tracking.
*/
if (fd != -1) {
/*
* Use "fd" to pass (some) Mach VM allocation flags,
* (see the VM_FLAGS_* definitions).
*/
alloc_flags = fd & (VM_FLAGS_ALIAS_MASK |
VM_FLAGS_PURGABLE);
if (alloc_flags != fd) {
/* reject if there are any extra flags */
return EINVAL;
}
}
handle = NULL;
maxprot = VM_PROT_ALL;
file_pos = 0;
mapanon = 1;
} else {
struct vnode_attr va;
vfs_context_t ctx = vfs_context_current();
/*
* Mapping file, get fp for validation. Obtain vnode and make
* sure it is of appropriate type.
*/
err = fp_lookup(p, fd, &fp, 0);
if (err)
return(err);
fpref = 1;
if(fp->f_fglob->fg_type == DTYPE_PSXSHM) {
uap->addr = (user_addr_t)user_addr;
uap->len = (user_size_t)user_size;
uap->prot = prot;
uap->flags = flags;
uap->pos = file_pos;
error = pshm_mmap(p, uap, retval, fp, (off_t)pageoff);
goto bad;
}
if (fp->f_fglob->fg_type != DTYPE_VNODE) {
error = EINVAL;
goto bad;
}
vp = (struct vnode *)fp->f_fglob->fg_data;
error = vnode_getwithref(vp);
if(error != 0)
goto bad;
if (vp->v_type != VREG && vp->v_type != VCHR) {
(void)vnode_put(vp);
error = EINVAL;
goto bad;
}
AUDIT_ARG(vnpath, vp, ARG_VNODE1);
/*
* POSIX: mmap needs to update access time for mapped files
*/
if ((vnode_vfsvisflags(vp) & MNT_NOATIME) == 0) {
VATTR_INIT(&va);
nanotime(&va.va_access_time);
VATTR_SET_ACTIVE(&va, va_access_time);
vnode_setattr(vp, &va, ctx);
}
/*
* XXX hack to handle use of /dev/zero to map anon memory (ala
* SunOS).
*/
if (vp->v_type == VCHR || vp->v_type == VSTR) {
(void)vnode_put(vp);
error = ENODEV;
goto bad;
} else {
/*
* Ensure that file and memory protections are
* compatible. Note that we only worry about
* writability if mapping is shared; in this case,
* current and max prot are dictated by the open file.
* XXX use the vnode instead? Problem is: what
* credentials do we use for determination? What if
* proc does a setuid?
*/
maxprot = VM_PROT_EXECUTE; /* ??? */
if (fp->f_fglob->fg_flag & FREAD)
maxprot |= VM_PROT_READ;
else if (prot & PROT_READ) {
(void)vnode_put(vp);
error = EACCES;
goto bad;
}
/*
* If we are sharing potential changes (either via
* MAP_SHARED or via the implicit sharing of character
* device mappings), and we are trying to get write
* permission although we opened it without asking
* for it, bail out.
*/
if ((flags & MAP_SHARED) != 0) {
if ((fp->f_fglob->fg_flag & FWRITE) != 0) {
/*
* check for write access
*
* Note that we already made this check when granting FWRITE
* against the file, so it seems redundant here.
*/
error = vnode_authorize(vp, NULL, KAUTH_VNODE_CHECKIMMUTABLE, ctx);
/* if not granted for any reason, but we wanted it, bad */
if ((prot & PROT_WRITE) && (error != 0)) {
vnode_put(vp);
goto bad;
}
/* if writable, remember */
if (error == 0)
maxprot |= VM_PROT_WRITE;
} else if ((prot & PROT_WRITE) != 0) {
(void)vnode_put(vp);
error = EACCES;
goto bad;
}
} else
maxprot |= VM_PROT_WRITE;
handle = (void *)vp;
#if CONFIG_MACF
error = mac_file_check_mmap(vfs_context_ucred(ctx),
fp->f_fglob, prot, flags, &maxprot);
if (error) {
(void)vnode_put(vp);
goto bad;
}
#endif /* MAC */
}
}
if (user_size == 0) {
if (!mapanon)
(void)vnode_put(vp);
error = 0;
goto bad;
}
/*
* We bend a little - round the start and end addresses
* to the nearest page boundary.
*/
user_size = mach_vm_round_page(user_size);
if (file_pos & PAGE_MASK_64) {
if (!mapanon)
(void)vnode_put(vp);
error = EINVAL;
goto bad;
}
user_map = current_map();
if ((flags & MAP_FIXED) == 0) {
alloc_flags |= VM_FLAGS_ANYWHERE;
user_addr = mach_vm_round_page(user_addr);
} else {
if (user_addr != mach_vm_trunc_page(user_addr)) {
if (!mapanon)
(void)vnode_put(vp);
error = EINVAL;
goto bad;
}
/*
* mmap(MAP_FIXED) will replace any existing mappings in the
* specified range, if the new mapping is successful.
* If we just deallocate the specified address range here,
* another thread might jump in and allocate memory in that
* range before we get a chance to establish the new mapping,
* and we won't have a chance to restore the old mappings.
* So we use VM_FLAGS_OVERWRITE to let Mach VM know that it
* has to deallocate the existing mappings and establish the
* new ones atomically.
*/
alloc_flags |= VM_FLAGS_FIXED | VM_FLAGS_OVERWRITE;
}
if (flags & MAP_NOCACHE)
alloc_flags |= VM_FLAGS_NO_CACHE;
/*
* Lookup/allocate object.
*/
if (handle == NULL) {
pager = NULL;
#ifdef notyet
/* Hmm .. */
#if defined(VM_PROT_READ_IS_EXEC)
if (prot & VM_PROT_READ)
prot |= VM_PROT_EXECUTE;
if (maxprot & VM_PROT_READ)
maxprot |= VM_PROT_EXECUTE;
#endif
#endif
#if 3777787
if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
prot |= VM_PROT_READ;
if (maxprot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
maxprot |= VM_PROT_READ;
#endif /* radar 3777787 */
result = vm_map_enter_mem_object(user_map,
&user_addr, user_size,
0, alloc_flags,
IPC_PORT_NULL, 0, FALSE,
prot, maxprot,
(flags & MAP_SHARED) ?
VM_INHERIT_SHARE :
VM_INHERIT_DEFAULT);
if (result != KERN_SUCCESS)
goto out;
} else {
pager = (vm_pager_t)ubc_getpager(vp);
if (pager == NULL) {
(void)vnode_put(vp);
error = ENOMEM;
goto bad;
}
/*
* Set credentials:
* FIXME: if we're writing the file we need a way to
* ensure that someone doesn't replace our R/W creds
* with ones that only work for read.
*/
ubc_setthreadcred(vp, p, current_thread());
docow = FALSE;
if ((flags & (MAP_ANON|MAP_SHARED)) == 0) {
docow = TRUE;
}
#ifdef notyet
/* Hmm .. */
#if defined(VM_PROT_READ_IS_EXEC)
if (prot & VM_PROT_READ)
prot |= VM_PROT_EXECUTE;
if (maxprot & VM_PROT_READ)
maxprot |= VM_PROT_EXECUTE;
#endif
#endif /* notyet */
#if 3777787
if (prot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
prot |= VM_PROT_READ;
if (maxprot & (VM_PROT_EXECUTE | VM_PROT_WRITE))
maxprot |= VM_PROT_READ;
#endif /* radar 3777787 */
result = vm_map_enter_mem_object(user_map,
&user_addr, user_size,
0, alloc_flags,
(ipc_port_t)pager, file_pos,
docow, prot, maxprot,
(flags & MAP_SHARED) ?
VM_INHERIT_SHARE :
VM_INHERIT_DEFAULT);
if (result != KERN_SUCCESS) {
(void)vnode_put(vp);
goto out;
}
file_prot = prot & (PROT_READ | PROT_WRITE | PROT_EXEC);
if (docow) {
/* private mapping: won't write to the file */
file_prot &= ~PROT_WRITE;
}
(void) ubc_map(vp, file_prot);
}
if (!mapanon)
(void)vnode_put(vp);
out:
switch (result) {
case KERN_SUCCESS:
*retval = user_addr + pageoff;
error = 0;
break;
case KERN_INVALID_ADDRESS:
case KERN_NO_SPACE:
error = ENOMEM;
break;
case KERN_PROTECTION_FAILURE:
error = EACCES;
break;
default:
error = EINVAL;
break;
}
bad:
if (fpref)
fp_drop(p, fd, fp, 0);
KERNEL_DEBUG_CONSTANT((BSDDBG_CODE(DBG_BSD_SC_EXTENDED_INFO, SYS_mmap) | DBG_FUNC_NONE), fd, (uint32_t)(*retval), (uint32_t)user_size, error, 0);
KERNEL_DEBUG_CONSTANT((BSDDBG_CODE(DBG_BSD_SC_EXTENDED_INFO2, SYS_mmap) | DBG_FUNC_NONE), (uint32_t)(*retval >> 32), (uint32_t)(user_size >> 32),
(uint32_t)(file_pos >> 32), (uint32_t)file_pos, 0);
return(error);
}
void
unix_syscall(struct i386_saved_state *regs)
{
thread_act_t thread;
void *vt;
unsigned short code;
struct sysent *callp;
int nargs, error;
volatile int *rval;
int funnel_type;
vm_offset_t params;
extern int nsysent;
struct proc *p;
struct proc *current_proc();
thread = current_act();
p = current_proc();
rval = (int *)get_bsduthreadrval(thread);
//printf("[scall : eax %x]", regs->eax);
code = regs->eax;
params = (vm_offset_t) ((caddr_t)regs->uesp + sizeof (int));
callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
if (callp == sysent) {
code = fuword(params);
params += sizeof (int);
callp = (code >= nsysent) ? &sysent[63] : &sysent[code];
}
vt = get_bsduthreadarg(thread);
if ((nargs = (callp->sy_narg * sizeof (int))) &&
(error = copyin((char *) params, (char *)vt , nargs)) != 0) {
regs->eax = error;
regs->efl |= EFL_CF;
thread_exception_return();
/* NOTREACHED */
}
rval[0] = 0;
rval[1] = regs->edx;
funnel_type = callp->sy_funnel;
if(funnel_type == KERNEL_FUNNEL)
(void) thread_funnel_set(kernel_flock, TRUE);
else if (funnel_type == NETWORK_FUNNEL)
(void) thread_funnel_set(network_flock, TRUE);
set_bsduthreadargs(thread, regs, NULL);
if (callp->sy_narg > 8)
panic("unix_syscall max arg count exceeded (%d)", callp->sy_narg);
ktrsyscall(p, code, callp->sy_narg, vt, funnel_type);
{
int *ip = (int *)vt;
KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_START,
*ip, *(ip+1), *(ip+2), *(ip+3), 0);
}
error = (*(callp->sy_call))(p, (void *) vt, (int *) &rval[0]);
#if 0
/* May be needed with vfork changes */
regs = USER_REGS(thread);
#endif
if (error == ERESTART) {
regs->eip -= 7;
}
else if (error != EJUSTRETURN) {
if (error) {
regs->eax = error;
regs->efl |= EFL_CF; /* carry bit */
} else { /* (not error) */
regs->eax = rval[0];
regs->edx = rval[1];
regs->efl &= ~EFL_CF;
}
}
ktrsysret(p, code, error, rval[0], funnel_type);
KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_EXCP_SC, code) | DBG_FUNC_END,
error, rval[0], rval[1], 0, 0);
if(funnel_type != NO_FUNNEL)
(void) thread_funnel_set(current_thread()->funnel_lock, FALSE);
thread_exception_return();
/* NOTREACHED */
}
int
ptrace(struct proc *p, struct ptrace_args *uap, int32_t *retval)
{
struct proc *t = current_proc(); /* target process */
task_t task;
thread_t th_act;
struct uthread *ut;
int tr_sigexc = 0;
int error = 0;
int stopped = 0;
AUDIT_ARG(cmd, uap->req);
AUDIT_ARG(pid, uap->pid);
AUDIT_ARG(addr, uap->addr);
AUDIT_ARG(value32, uap->data);
if (uap->req == PT_DENY_ATTACH) {
proc_lock(p);
if (ISSET(p->p_lflag, P_LTRACED)) {
proc_unlock(p);
KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_FRCEXIT) | DBG_FUNC_NONE,
p->p_pid, W_EXITCODE(ENOTSUP, 0), 4, 0, 0);
exit1(p, W_EXITCODE(ENOTSUP, 0), retval);
thread_exception_return();
/* NOTREACHED */
}
SET(p->p_lflag, P_LNOATTACH);
proc_unlock(p);
return(0);
}
if (uap->req == PT_FORCEQUOTA) {
if (kauth_cred_issuser(kauth_cred_get())) {
OSBitOrAtomic(P_FORCEQUOTA, &t->p_flag);
return (0);
} else
return (EPERM);
}
/*
* Intercept and deal with "please trace me" request.
*/
if (uap->req == PT_TRACE_ME) {
retry_trace_me:;
proc_t pproc = proc_parent(p);
if (pproc == NULL)
return (EINVAL);
#if CONFIG_MACF
/*
* NB: Cannot call kauth_authorize_process(..., KAUTH_PROCESS_CANTRACE, ...)
* since that assumes the process being checked is the current process
* when, in this case, it is the current process's parent.
* Most of the other checks in cantrace() don't apply either.
*/
if ((error = mac_proc_check_debug(pproc, p)) == 0) {
#endif
proc_lock(p);
/* Make sure the process wasn't re-parented. */
if (p->p_ppid != pproc->p_pid) {
proc_unlock(p);
proc_rele(pproc);
goto retry_trace_me;
}
SET(p->p_lflag, P_LTRACED);
/* Non-attached case, our tracer is our parent. */
p->p_oppid = p->p_ppid;
proc_unlock(p);
/* Child and parent will have to be able to run modified code. */
cs_allow_invalid(p);
cs_allow_invalid(pproc);
#if CONFIG_MACF
}
#endif
proc_rele(pproc);
return (error);
}
if (uap->req == PT_SIGEXC) {
proc_lock(p);
if (ISSET(p->p_lflag, P_LTRACED)) {
SET(p->p_lflag, P_LSIGEXC);
proc_unlock(p);
return(0);
} else {
proc_unlock(p);
return(EINVAL);
}
}
/*
* We do not want ptrace to do anything with kernel or launchd
*/
if (uap->pid < 2) {
return(EPERM);
}
/*
* Locate victim, and make sure it is traceable.
*/
if ((t = proc_find(uap->pid)) == NULL)
return (ESRCH);
AUDIT_ARG(process, t);
task = t->task;
if (uap->req == PT_ATTACHEXC) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
uap->req = PT_ATTACH;
tr_sigexc = 1;
}
if (uap->req == PT_ATTACH) {
#pragma clang diagnostic pop
int err;
if ( kauth_authorize_process(proc_ucred(p), KAUTH_PROCESS_CANTRACE,
t, (uintptr_t)&err, 0, 0) == 0 ) {
/* it's OK to attach */
proc_lock(t);
SET(t->p_lflag, P_LTRACED);
if (tr_sigexc)
SET(t->p_lflag, P_LSIGEXC);
t->p_oppid = t->p_ppid;
/* Check whether child and parent are allowed to run modified
* code (they'll have to) */
proc_unlock(t);
cs_allow_invalid(t);
cs_allow_invalid(p);
if (t->p_pptr != p)
proc_reparentlocked(t, p, 1, 0);
proc_lock(t);
if (get_task_userstop(task) > 0 ) {
stopped = 1;
}
t->p_xstat = 0;
proc_unlock(t);
psignal(t, SIGSTOP);
/*
* If the process was stopped, wake up and run through
* issignal() again to properly connect to the tracing
* process.
*/
if (stopped)
task_resume(task);
error = 0;
goto out;
}
else {
/* not allowed to attach, proper error code returned by kauth_authorize_process */
if (ISSET(t->p_lflag, P_LNOATTACH)) {
psignal(p, SIGSEGV);
}
error = err;
goto out;
}
}
/*
* You can't do what you want to the process if:
* (1) It's not being traced at all,
*/
proc_lock(t);
if (!ISSET(t->p_lflag, P_LTRACED)) {
proc_unlock(t);
error = EPERM;
goto out;
}
/*
* (2) it's not being traced by _you_, or
*/
if (t->p_pptr != p) {
proc_unlock(t);
error = EBUSY;
goto out;
}
/*
* (3) it's not currently stopped.
*/
if (t->p_stat != SSTOP) {
proc_unlock(t);
error = EBUSY;
goto out;
}
/*
* Mach version of ptrace executes request directly here,
* thus simplifying the interaction of ptrace and signals.
*/
/* proc lock is held here */
switch (uap->req) {
case PT_DETACH:
if (t->p_oppid != t->p_ppid) {
struct proc *pp;
proc_unlock(t);
pp = proc_find(t->p_oppid);
if (pp != PROC_NULL) {
proc_reparentlocked(t, pp, 1, 0);
proc_rele(pp);
} else {
/* original parent exited while traced */
proc_list_lock();
t->p_listflag |= P_LIST_DEADPARENT;
proc_list_unlock();
proc_reparentlocked(t, initproc, 1, 0);
}
proc_lock(t);
}
t->p_oppid = 0;
CLR(t->p_lflag, P_LTRACED);
CLR(t->p_lflag, P_LSIGEXC);
proc_unlock(t);
goto resume;
case PT_KILL:
/*
* Tell child process to kill itself after it
* is resumed by adding NSIG to p_cursig. [see issig]
*/
proc_unlock(t);
#if CONFIG_MACF
error = mac_proc_check_signal(p, t, SIGKILL);
if (0 != error)
goto resume;
#endif
psignal(t, SIGKILL);
goto resume;
case PT_STEP: /* single step the child */
case PT_CONTINUE: /* continue the child */
proc_unlock(t);
th_act = (thread_t)get_firstthread(task);
if (th_act == THREAD_NULL) {
error = EINVAL;
goto out;
}
/* force use of Mach SPIs (and task_for_pid security checks) to adjust PC */
if (uap->addr != (user_addr_t)1) {
error = ENOTSUP;
goto out;
}
if ((unsigned)uap->data >= NSIG) {
error = EINVAL;
goto out;
}
if (uap->data != 0) {
#if CONFIG_MACF
error = mac_proc_check_signal(p, t, uap->data);
if (0 != error)
goto out;
#endif
psignal(t, uap->data);
}
if (uap->req == PT_STEP) {
/*
* set trace bit
* we use sending SIGSTOP as a comparable security check.
*/
#if CONFIG_MACF
error = mac_proc_check_signal(p, t, SIGSTOP);
if (0 != error) {
goto out;
}
#endif
if (thread_setsinglestep(th_act, 1) != KERN_SUCCESS) {
error = ENOTSUP;
goto out;
}
} else {
/*
* clear trace bit if on
* we use sending SIGCONT as a comparable security check.
*/
#if CONFIG_MACF
error = mac_proc_check_signal(p, t, SIGCONT);
if (0 != error) {
goto out;
}
#endif
if (thread_setsinglestep(th_act, 0) != KERN_SUCCESS) {
error = ENOTSUP;
goto out;
}
}
resume:
proc_lock(t);
t->p_xstat = uap->data;
t->p_stat = SRUN;
if (t->sigwait) {
wakeup((caddr_t)&(t->sigwait));
proc_unlock(t);
if ((t->p_lflag & P_LSIGEXC) == 0) {
task_resume(task);
}
} else
proc_unlock(t);
break;
case PT_THUPDATE: {
proc_unlock(t);
if ((unsigned)uap->data >= NSIG) {
error = EINVAL;
goto out;
}
th_act = port_name_to_thread(CAST_MACH_PORT_TO_NAME(uap->addr));
if (th_act == THREAD_NULL) {
error = ESRCH;
goto out;
}
ut = (uthread_t)get_bsdthread_info(th_act);
if (uap->data)
ut->uu_siglist |= sigmask(uap->data);
proc_lock(t);
t->p_xstat = uap->data;
t->p_stat = SRUN;
proc_unlock(t);
thread_deallocate(th_act);
error = 0;
}
break;
default:
proc_unlock(t);
error = EINVAL;
goto out;
}
error = 0;
out:
proc_rele(t);
return(error);
}
