int
procfs_dofpregs(struct proc *curp, struct lwp *lp, struct pfsnode *pfs,
struct uio *uio)
{
struct proc *p = lp->lwp_proc;
int error;
struct fpreg r;
/* Can't trace a process that's currently exec'ing. */
if ((p->p_flags & P_INEXEC) != 0)
return EAGAIN;
if (!CHECKIO(curp, p) || p_trespass(curp->p_ucred, p->p_ucred))
return EPERM;
LWPHOLD(lp);
error = procfs_read_fpregs(lp, &r);
if (error == 0)
error = uiomove_frombuf(&r, sizeof(r), uio);
if (error == 0 && uio->uio_rw == UIO_WRITE) {
if (lp->lwp_stat != LSSTOP)
error = EBUSY;
else
error = procfs_write_fpregs(lp, &r);
}
LWPRELE(lp);
uio->uio_offset = 0;
return (error);
}
/*
* Kill all LWPs except the current one. Do not try to signal
* LWPs which have exited on their own or have already been
* signaled.
*/
static void
killlwps(struct lwp *lp)
{
struct proc *p = lp->lwp_proc;
struct lwp *tlp;
/*
* Kill the remaining LWPs. We must send the signal before setting
* LWP_WEXIT. The setting of WEXIT is optional but helps reduce
* races. tlp must be held across the call as it might block and
* allow the target lwp to rip itself out from under our loop.
*/
FOREACH_LWP_IN_PROC(tlp, p) {
LWPHOLD(tlp);
if ((tlp->lwp_flag & LWP_WEXIT) == 0) {
lwpsignal(p, tlp, SIGKILL);
tlp->lwp_flag |= LWP_WEXIT;
}
LWPRELE(tlp);
}
/*
* MPALMOSTSAFE
*/
int
sys_linux_ptrace(struct linux_ptrace_args *uap)
{
struct thread *td = curthread;
struct proc *curp = td->td_proc;
union {
struct linux_pt_reg reg;
struct linux_pt_fpreg fpreg;
struct linux_pt_fpxreg fpxreg;
} r;
union {
struct reg bsd_reg;
struct fpreg bsd_fpreg;
struct dbreg bsd_dbreg;
} u;
void *addr;
pid_t pid;
int error, req;
struct proc *p = NULL; /* held process */
error = 0;
/* by default, just copy data intact */
req = uap->req;
pid = (pid_t)uap->pid;
addr = (void *)uap->addr;
switch (req) {
case PTRACE_TRACEME:
case PTRACE_POKETEXT:
case PTRACE_POKEDATA:
case PTRACE_KILL:
error = kern_ptrace(curp, req, pid, addr, uap->data,
&uap->sysmsg_iresult);
break;
case PTRACE_PEEKTEXT:
case PTRACE_PEEKDATA: {
/* need to preserve return value, use dummy */
l_int rval = 0;
error = kern_ptrace(curp, req, pid, addr, 0, &rval);
if (error == 0) {
error = copyout(&rval, (caddr_t)uap->data, sizeof(l_int));
}
break;
}
case PTRACE_DETACH:
error = kern_ptrace(curp, PT_DETACH, pid, (void *)1,
map_signum(uap->data),
&uap->sysmsg_iresult);
break;
case PTRACE_SINGLESTEP:
case PTRACE_CONT:
error = kern_ptrace(curp, req, pid, (void *)1,
map_signum(uap->data),
&uap->sysmsg_iresult);
break;
case PTRACE_ATTACH:
error = kern_ptrace(curp, PT_ATTACH, pid, addr, uap->data,
&uap->sysmsg_iresult);
break;
case PTRACE_GETREGS:
/* Linux is using data where FreeBSD is using addr */
error = kern_ptrace(curp, PT_GETREGS, pid, &u.bsd_reg, 0,
&uap->sysmsg_iresult);
if (error == 0) {
map_regs_to_linux(&u.bsd_reg, &r.reg);
error = copyout(&r.reg, (void *)uap->data,
sizeof(r.reg));
}
break;
case PTRACE_SETREGS:
/* Linux is using data where FreeBSD is using addr */
error = copyin((caddr_t)uap->data, &r.reg, sizeof(r.reg));
if (error == 0) {
map_regs_from_linux(&u.bsd_reg, &r.reg);
error = kern_ptrace(curp, PT_SETREGS, pid, &u.bsd_reg,
0, &uap->sysmsg_iresult);
}
break;
case PTRACE_GETFPREGS:
/* Linux is using data where FreeBSD is using addr */
error = kern_ptrace(curp, PT_GETFPREGS, pid, &u.bsd_fpreg,
0, &uap->sysmsg_iresult);
if (error == 0) {
map_fpregs_to_linux(&u.bsd_fpreg, &r.fpreg);
error = copyout(&r.fpreg, (caddr_t)uap->data,
sizeof(r.fpreg));
}
break;
case PTRACE_SETFPREGS:
/* Linux is using data where FreeBSD is using addr */
error = copyin((caddr_t)uap->data, &r.fpreg, sizeof(r.fpreg));
if (error == 0) {
map_fpregs_from_linux(&u.bsd_fpreg, &r.fpreg);
error = kern_ptrace(curp, PT_SETFPREGS, pid,
&u.bsd_fpreg,
0, &uap->sysmsg_iresult);
}
break;
case PTRACE_SETFPXREGS:
#ifndef CPU_DISABLE_SSE
error = copyin((caddr_t)uap->data, &r.fpxreg,
sizeof(r.fpxreg));
if (error)
break;
#endif
/* FALL THROUGH */
case PTRACE_GETFPXREGS: {
#ifndef CPU_DISABLE_SSE
struct proc *p;
struct lwp *lp;
if (sizeof(struct linux_pt_fpxreg) != sizeof(struct savexmm)) {
static int once = 0;
if (!once) {
kprintf("linux: savexmm != linux_pt_fpxreg\n");
once = 1;
}
error = EIO;
break;
}
if ((p = pfind(uap->pid)) == NULL) {
error = ESRCH;
break;
}
if (!PRISON_CHECK(curp->p_ucred, p->p_ucred)) {
error = ESRCH;
goto fail;
}
/* System processes can't be debugged. */
if ((p->p_flag & P_SYSTEM) != 0) {
error = EINVAL;
goto fail;
}
/* not being traced... */
if ((p->p_flag & P_TRACED) == 0) {
error = EPERM;
goto fail;
}
/* not being traced by YOU */
if (p->p_pptr != curp) {
error = EBUSY;
goto fail;
}
/* not currently stopped */
if ((p->p_flag & (P_TRACED|P_WAITED)) == 0) {
error = EBUSY;
goto fail;
}
/* XXX lwp */
lp = FIRST_LWP_IN_PROC(p);
if (req == PTRACE_GETFPXREGS) {
LWPHOLD(lp);
error = linux_proc_read_fpxregs(lp, &r.fpxreg);
LWPRELE(lp);
if (error == 0)
error = copyout(&r.fpxreg, (caddr_t)uap->data,
sizeof(r.fpxreg));
} else {
/* clear dangerous bits exactly as Linux does*/
r.fpxreg.mxcsr &= 0xffbf;
LWPHOLD(lp);
error = linux_proc_write_fpxregs(lp, &r.fpxreg);
LWPRELE(lp);
}
break;
fail:
#else
error = EIO;
#endif
break;
}
case PTRACE_PEEKUSR:
case PTRACE_POKEUSR: {
error = EIO;
/* check addr for alignment */
if (uap->addr < 0 || uap->addr & (sizeof(l_int) - 1))
break;
/*
* Allow linux programs to access register values in
* user struct. We simulate this through PT_GET/SETREGS
* as necessary.
*/
if (uap->addr < sizeof(struct linux_pt_reg)) {
error = kern_ptrace(curp, PT_GETREGS, pid, &u.bsd_reg,
0, &uap->sysmsg_iresult);
if (error != 0)
break;
map_regs_to_linux(&u.bsd_reg, &r.reg);
if (req == PTRACE_PEEKUSR) {
error = copyout((char *)&r.reg + uap->addr,
(caddr_t)uap->data, sizeof(l_int));
break;
}
*(l_int *)((char *)&r.reg + uap->addr) =
(l_int)uap->data;
map_regs_from_linux(&u.bsd_reg, &r.reg);
error = kern_ptrace(curp, PT_SETREGS, pid, &u.bsd_reg,
0, &uap->sysmsg_iresult);
}
/*
* Simulate debug registers access
*/
if (uap->addr >= LINUX_DBREG_OFFSET &&
uap->addr <= LINUX_DBREG_OFFSET + LINUX_DBREG_SIZE) {
error = kern_ptrace(curp, PT_GETDBREGS, pid,
&u.bsd_dbreg,
0, &uap->sysmsg_iresult);
if (error != 0)
break;
uap->addr -= LINUX_DBREG_OFFSET;
if (req == PTRACE_PEEKUSR) {
error = copyout((char *)&u.bsd_dbreg +
uap->addr, (caddr_t)uap->data,
sizeof(l_int));
break;
}
*(l_int *)((char *)&u.bsd_dbreg + uap->addr) =
uap->data;
error = kern_ptrace(curp, PT_SETDBREGS, pid,
&u.bsd_dbreg,
0, &uap->sysmsg_iresult);
}
break;
}
case PTRACE_SYSCALL:
/* fall through */
default:
kprintf("linux: ptrace(%u, ...) not implemented\n",
(unsigned int)uap->req);
error = EINVAL;
break;
}
/*
* Release held proces (if any) before returning.
*/
if (p)
PRELE(p);
return (error);
}
static int
procfs_control(struct proc *curp, struct lwp *lp, int op)
{
struct proc *p = lp->lwp_proc;
int error;
ASSERT_LWKT_TOKEN_HELD(&p->p_token);
ASSERT_LWKT_TOKEN_HELD(&proc_token);
/* Can't trace a process that's currently exec'ing. */
if ((p->p_flags & P_INEXEC) != 0)
return EAGAIN;
/*
* Authorization check: rely on normal debugging protection, except
* allow processes to disengage debugging on a process onto which
* they have previously attached, but no longer have permission to
* debug.
*/
if (op != PROCFS_CTL_DETACH) {
if (securelevel > 0 && p->p_pid == 1)
return (EPERM);
if (!CHECKIO(curp, p) || p_trespass(curp->p_ucred, p->p_ucred))
return (EPERM);
}
/*
* Attach - attaches the target process for debugging
* by the calling process.
*/
if (op == PROCFS_CTL_ATTACH) {
/* check whether already being traced */
if (p->p_flags & P_TRACED)
return (EBUSY);
/* can't trace yourself! */
if (p->p_pid == curp->p_pid)
return (EINVAL);
/*
* Go ahead and set the trace flag.
* Save the old parent (it's reset in
* _DETACH, and also in kern_exit.c:wait4()
* Reparent the process so that the tracing
* proc gets to see all the action.
* Stop the target.
*/
p->p_flags |= P_TRACED;
faultin(p);
p->p_xstat = 0; /* XXX ? */
if (p->p_pptr != curp) {
p->p_oppid = p->p_pptr->p_pid;
proc_reparent(p, curp);
}
proc_stop(p);
return (0);
}
/*
* Target process must be stopped, owned by (curp) and
* be set up for tracing (P_TRACED flag set).
* Allow DETACH to take place at any time for sanity.
* Allow WAIT any time, of course.
*/
switch (op) {
case PROCFS_CTL_DETACH:
case PROCFS_CTL_WAIT:
break;
default:
if (!TRACE_WAIT_P(curp, p))
return (EBUSY);
}
#ifdef FIX_SSTEP
/*
* do single-step fixup if needed
*/
FIX_SSTEP(lp);
#endif
/*
* Don't deliver any signal by default.
* To continue with a signal, just send
* the signal name to the ctl file
*/
p->p_xstat = 0;
switch (op) {
/*
* Detach. Cleans up the target process, reparent it if possible
* and set it running once more.
*/
case PROCFS_CTL_DETACH:
/* if not being traced, then this is a painless no-op */
if ((p->p_flags & P_TRACED) == 0)
return (0);
/* not being traced any more */
p->p_flags &= ~P_TRACED;
/* remove pending SIGTRAP, else the process will die */
spin_lock(&lp->lwp_spin);
lwp_delsig(lp, SIGTRAP);
spin_unlock(&lp->lwp_spin);
/* give process back to original parent */
if (p->p_oppid != p->p_pptr->p_pid) {
struct proc *pp;
pp = pfs_pfind(p->p_oppid);
if (pp) {
proc_reparent(p, pp);
pfs_pdone(pp);
}
}
p->p_oppid = 0;
p->p_flags &= ~P_WAITED; /* XXX ? */
wakeup((caddr_t) curp); /* XXX for CTL_WAIT below ? */
break;
/*
* Step. Let the target process execute a single instruction.
*/
case PROCFS_CTL_STEP:
LWPHOLD(lp);
error = procfs_sstep(lp);
LWPRELE(lp);
if (error)
return (error);
break;
/*
* Run. Let the target process continue running until a breakpoint
* or some other trap.
*/
case PROCFS_CTL_RUN:
break;
/*
* Wait for the target process to stop.
* If the target is not being traced then just wait
* to enter
*/
case PROCFS_CTL_WAIT:
error = 0;
if (p->p_flags & P_TRACED) {
while (error == 0 &&
p->p_stat != SSTOP &&
(p->p_flags & P_TRACED) &&
(p->p_pptr == curp)) {
error = tsleep((caddr_t) p,
PCATCH, "procfsx", 0);
}
if (error == 0 && !TRACE_WAIT_P(curp, p))
error = EBUSY;
} else {
while (error == 0 && p->p_stat != SSTOP) {
error = tsleep((caddr_t) p,
PCATCH, "procfs", 0);
}
}
return (error);
default:
panic("procfs_control");
}
/*
* If the process is in a stopped state, make it runnable again.
* Do not set LWP_MP_BREAKTSLEEP - that is, do not break a tsleep
* that might be in progress.
*/
if (p->p_stat == SSTOP)
proc_unstop(p);
return (0);
}
