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kernel/arch/ia64/kernel/ptrace.c
tqcq e5480701d3 init repo.
2024-07-22 17:22:30 +08:00

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// SPDX-License-Identifier: GPL-2.0
/*
* Kernel support for the ptrace() and syscall tracing interfaces.
*
* Copyright (C) 1999-2005 Hewlett-Packard Co
* David Mosberger-Tang <davidm@hpl.hp.com>
* Copyright (C) 2006 Intel Co
* 2006-08-12 - IA64 Native Utrace implementation support added by
* Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
*
* Derived from the x86 and Alpha versions.
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/sched/task.h>
#include <linux/sched/task_stack.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/security.h>
#include <linux/audit.h>
#include <linux/signal.h>
#include <linux/regset.h>
#include <linux/elf.h>
#include <linux/tracehook.h>
#include <asm/processor.h>
#include <asm/ptrace_offsets.h>
#include <asm/rse.h>
#include <linux/uaccess.h>
#include <asm/unwind.h>
#include "entry.h"
/*
* Bits in the PSR that we allow ptrace() to change:
* be, up, ac, mfl, mfh (the user mask; five bits total)
* db (debug breakpoint fault; one bit)
* id (instruction debug fault disable; one bit)
* dd (data debug fault disable; one bit)
* ri (restart instruction; two bits)
* is (instruction set; one bit)
*/
#define IPSR_MASK (IA64_PSR_UM | IA64_PSR_DB | IA64_PSR_IS \
| IA64_PSR_ID | IA64_PSR_DD | IA64_PSR_RI)
#define MASK(nbits) ((1UL << (nbits)) - 1) /* mask with NBITS bits set */
#define PFM_MASK MASK(38)
#define PTRACE_DEBUG 0
#if PTRACE_DEBUG
# define dprintk(format...) printk(format)
# define inline
#else
# define dprintk(format...)
#endif
/* Return TRUE if PT was created due to kernel-entry via a system-call. */
static inline int
in_syscall (struct pt_regs *pt)
{
return (long) pt->cr_ifs >= 0;
}
/*
* Collect the NaT bits for r1-r31 from scratch_unat and return a NaT
* bitset where bit i is set iff the NaT bit of register i is set.
*/
unsigned long
ia64_get_scratch_nat_bits (struct pt_regs *pt, unsigned long scratch_unat)
{
# define GET_BITS(first, last, unat) \
({ \
unsigned long bit = ia64_unat_pos(&pt->r##first); \
unsigned long nbits = (last - first + 1); \
unsigned long mask = MASK(nbits) << first; \
unsigned long dist; \
if (bit < first) \
dist = 64 + bit - first; \
else \
dist = bit - first; \
ia64_rotr(unat, dist) & mask; \
})
unsigned long val;
/*
* Registers that are stored consecutively in struct pt_regs
* can be handled in parallel. If the register order in
* struct_pt_regs changes, this code MUST be updated.
*/
val = GET_BITS( 1, 1, scratch_unat);
val |= GET_BITS( 2, 3, scratch_unat);
val |= GET_BITS(12, 13, scratch_unat);
val |= GET_BITS(14, 14, scratch_unat);
val |= GET_BITS(15, 15, scratch_unat);
val |= GET_BITS( 8, 11, scratch_unat);
val |= GET_BITS(16, 31, scratch_unat);
return val;
# undef GET_BITS
}
/*
* Set the NaT bits for the scratch registers according to NAT and
* return the resulting unat (assuming the scratch registers are
* stored in PT).
*/
unsigned long
ia64_put_scratch_nat_bits (struct pt_regs *pt, unsigned long nat)
{
# define PUT_BITS(first, last, nat) \
({ \
unsigned long bit = ia64_unat_pos(&pt->r##first); \
unsigned long nbits = (last - first + 1); \
unsigned long mask = MASK(nbits) << first; \
long dist; \
if (bit < first) \
dist = 64 + bit - first; \
else \
dist = bit - first; \
ia64_rotl(nat & mask, dist); \
})
unsigned long scratch_unat;
/*
* Registers that are stored consecutively in struct pt_regs
* can be handled in parallel. If the register order in
* struct_pt_regs changes, this code MUST be updated.
*/
scratch_unat = PUT_BITS( 1, 1, nat);
scratch_unat |= PUT_BITS( 2, 3, nat);
scratch_unat |= PUT_BITS(12, 13, nat);
scratch_unat |= PUT_BITS(14, 14, nat);
scratch_unat |= PUT_BITS(15, 15, nat);
scratch_unat |= PUT_BITS( 8, 11, nat);
scratch_unat |= PUT_BITS(16, 31, nat);
return scratch_unat;
# undef PUT_BITS
}
#define IA64_MLX_TEMPLATE 0x2
#define IA64_MOVL_OPCODE 6
void
ia64_increment_ip (struct pt_regs *regs)
{
unsigned long w0, ri = ia64_psr(regs)->ri + 1;
if (ri > 2) {
ri = 0;
regs->cr_iip += 16;
} else if (ri == 2) {
get_user(w0, (char __user *) regs->cr_iip + 0);
if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
/*
* rfi'ing to slot 2 of an MLX bundle causes
* an illegal operation fault. We don't want
* that to happen...
*/
ri = 0;
regs->cr_iip += 16;
}
}
ia64_psr(regs)->ri = ri;
}
void
ia64_decrement_ip (struct pt_regs *regs)
{
unsigned long w0, ri = ia64_psr(regs)->ri - 1;
if (ia64_psr(regs)->ri == 0) {
regs->cr_iip -= 16;
ri = 2;
get_user(w0, (char __user *) regs->cr_iip + 0);
if (((w0 >> 1) & 0xf) == IA64_MLX_TEMPLATE) {
/*
* rfi'ing to slot 2 of an MLX bundle causes
* an illegal operation fault. We don't want
* that to happen...
*/
ri = 1;
}
}
ia64_psr(regs)->ri = ri;
}
/*
* This routine is used to read an rnat bits that are stored on the
* kernel backing store. Since, in general, the alignment of the user
* and kernel are different, this is not completely trivial. In
* essence, we need to construct the user RNAT based on up to two
* kernel RNAT values and/or the RNAT value saved in the child's
* pt_regs.
*
* user rbs
*
* +--------+ <-- lowest address
* | slot62 |
* +--------+
* | rnat | 0x....1f8
* +--------+
* | slot00 | \
* +--------+ |
* | slot01 | > child_regs->ar_rnat
* +--------+ |
* | slot02 | / kernel rbs
* +--------+ +--------+
* <- child_regs->ar_bspstore | slot61 | <-- krbs
* +- - - - + +--------+
* | slot62 |
* +- - - - + +--------+
* | rnat |
* +- - - - + +--------+
* vrnat | slot00 |
* +- - - - + +--------+
* = =
* +--------+
* | slot00 | \
* +--------+ |
* | slot01 | > child_stack->ar_rnat
* +--------+ |
* | slot02 | /
* +--------+
* <--- child_stack->ar_bspstore
*
* The way to think of this code is as follows: bit 0 in the user rnat
* corresponds to some bit N (0 <= N <= 62) in one of the kernel rnat
* value. The kernel rnat value holding this bit is stored in
* variable rnat0. rnat1 is loaded with the kernel rnat value that
* form the upper bits of the user rnat value.
*
* Boundary cases:
*
* o when reading the rnat "below" the first rnat slot on the kernel
* backing store, rnat0/rnat1 are set to 0 and the low order bits are
* merged in from pt->ar_rnat.
*
* o when reading the rnat "above" the last rnat slot on the kernel
* backing store, rnat0/rnat1 gets its value from sw->ar_rnat.
*/
static unsigned long
get_rnat (struct task_struct *task, struct switch_stack *sw,
unsigned long *krbs, unsigned long *urnat_addr,
unsigned long *urbs_end)
{
unsigned long rnat0 = 0, rnat1 = 0, urnat = 0, *slot0_kaddr;
unsigned long umask = 0, mask, m;
unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
long num_regs, nbits;
struct pt_regs *pt;
pt = task_pt_regs(task);
kbsp = (unsigned long *) sw->ar_bspstore;
ubspstore = (unsigned long *) pt->ar_bspstore;
if (urbs_end < urnat_addr)
nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_end);
else
nbits = 63;
mask = MASK(nbits);
/*
* First, figure out which bit number slot 0 in user-land maps
* to in the kernel rnat. Do this by figuring out how many
* register slots we're beyond the user's backingstore and
* then computing the equivalent address in kernel space.
*/
num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
shift = ia64_rse_slot_num(slot0_kaddr);
rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
rnat0_kaddr = rnat1_kaddr - 64;
if (ubspstore + 63 > urnat_addr) {
/* some bits need to be merged in from pt->ar_rnat */
umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
urnat = (pt->ar_rnat & umask);
mask &= ~umask;
if (!mask)
return urnat;
}
m = mask << shift;
if (rnat0_kaddr >= kbsp)
rnat0 = sw->ar_rnat;
else if (rnat0_kaddr > krbs)
rnat0 = *rnat0_kaddr;
urnat |= (rnat0 & m) >> shift;
m = mask >> (63 - shift);
if (rnat1_kaddr >= kbsp)
rnat1 = sw->ar_rnat;
else if (rnat1_kaddr > krbs)
rnat1 = *rnat1_kaddr;
urnat |= (rnat1 & m) << (63 - shift);
return urnat;
}
/*
* The reverse of get_rnat.
*/
static void
put_rnat (struct task_struct *task, struct switch_stack *sw,
unsigned long *krbs, unsigned long *urnat_addr, unsigned long urnat,
unsigned long *urbs_end)
{
unsigned long rnat0 = 0, rnat1 = 0, *slot0_kaddr, umask = 0, mask, m;
unsigned long *kbsp, *ubspstore, *rnat0_kaddr, *rnat1_kaddr, shift;
long num_regs, nbits;
struct pt_regs *pt;
unsigned long cfm, *urbs_kargs;
pt = task_pt_regs(task);
kbsp = (unsigned long *) sw->ar_bspstore;
ubspstore = (unsigned long *) pt->ar_bspstore;
urbs_kargs = urbs_end;
if (in_syscall(pt)) {
/*
* If entered via syscall, don't allow user to set rnat bits
* for syscall args.
*/
cfm = pt->cr_ifs;
urbs_kargs = ia64_rse_skip_regs(urbs_end, -(cfm & 0x7f));
}
if (urbs_kargs >= urnat_addr)
nbits = 63;
else {
if ((urnat_addr - 63) >= urbs_kargs)
return;
nbits = ia64_rse_num_regs(urnat_addr - 63, urbs_kargs);
}
mask = MASK(nbits);
/*
* First, figure out which bit number slot 0 in user-land maps
* to in the kernel rnat. Do this by figuring out how many
* register slots we're beyond the user's backingstore and
* then computing the equivalent address in kernel space.
*/
num_regs = ia64_rse_num_regs(ubspstore, urnat_addr + 1);
slot0_kaddr = ia64_rse_skip_regs(krbs, num_regs);
shift = ia64_rse_slot_num(slot0_kaddr);
rnat1_kaddr = ia64_rse_rnat_addr(slot0_kaddr);
rnat0_kaddr = rnat1_kaddr - 64;
if (ubspstore + 63 > urnat_addr) {
/* some bits need to be place in pt->ar_rnat: */
umask = MASK(ia64_rse_slot_num(ubspstore)) & mask;
pt->ar_rnat = (pt->ar_rnat & ~umask) | (urnat & umask);
mask &= ~umask;
if (!mask)
return;
}
/*
* Note: Section 11.1 of the EAS guarantees that bit 63 of an
* rnat slot is ignored. so we don't have to clear it here.
*/
rnat0 = (urnat << shift);
m = mask << shift;
if (rnat0_kaddr >= kbsp)
sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat0 & m);
else if (rnat0_kaddr > krbs)
*rnat0_kaddr = ((*rnat0_kaddr & ~m) | (rnat0 & m));
rnat1 = (urnat >> (63 - shift));
m = mask >> (63 - shift);
if (rnat1_kaddr >= kbsp)
sw->ar_rnat = (sw->ar_rnat & ~m) | (rnat1 & m);
else if (rnat1_kaddr > krbs)
*rnat1_kaddr = ((*rnat1_kaddr & ~m) | (rnat1 & m));
}
static inline int
on_kernel_rbs (unsigned long addr, unsigned long bspstore,
unsigned long urbs_end)
{
unsigned long *rnat_addr = ia64_rse_rnat_addr((unsigned long *)
urbs_end);
return (addr >= bspstore && addr <= (unsigned long) rnat_addr);
}
/*
* Read a word from the user-level backing store of task CHILD. ADDR
* is the user-level address to read the word from, VAL a pointer to
* the return value, and USER_BSP gives the end of the user-level
* backing store (i.e., it's the address that would be in ar.bsp after
* the user executed a "cover" instruction).
*
* This routine takes care of accessing the kernel register backing
* store for those registers that got spilled there. It also takes
* care of calculating the appropriate RNaT collection words.
*/
long
ia64_peek (struct task_struct *child, struct switch_stack *child_stack,
unsigned long user_rbs_end, unsigned long addr, long *val)
{
unsigned long *bspstore, *krbs, regnum, *laddr, *urbs_end, *rnat_addr;
struct pt_regs *child_regs;
size_t copied;
long ret;
urbs_end = (long *) user_rbs_end;
laddr = (unsigned long *) addr;
child_regs = task_pt_regs(child);
bspstore = (unsigned long *) child_regs->ar_bspstore;
krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
if (on_kernel_rbs(addr, (unsigned long) bspstore,
(unsigned long) urbs_end))
{
/*
* Attempt to read the RBS in an area that's actually
* on the kernel RBS => read the corresponding bits in
* the kernel RBS.
*/
rnat_addr = ia64_rse_rnat_addr(laddr);
ret = get_rnat(child, child_stack, krbs, rnat_addr, urbs_end);
if (laddr == rnat_addr) {
/* return NaT collection word itself */
*val = ret;
return 0;
}
if (((1UL << ia64_rse_slot_num(laddr)) & ret) != 0) {
/*
* It is implementation dependent whether the
* data portion of a NaT value gets saved on a
* st8.spill or RSE spill (e.g., see EAS 2.6,
* 4.4.4.6 Register Spill and Fill). To get
* consistent behavior across all possible
* IA-64 implementations, we return zero in
* this case.
*/
*val = 0;
return 0;
}
if (laddr < urbs_end) {
/*
* The desired word is on the kernel RBS and
* is not a NaT.
*/
regnum = ia64_rse_num_regs(bspstore, laddr);
*val = *ia64_rse_skip_regs(krbs, regnum);
return 0;
}
}
copied = access_process_vm(child, addr, &ret, sizeof(ret), FOLL_FORCE);
if (copied != sizeof(ret))
return -EIO;
*val = ret;
return 0;
}
long
ia64_poke (struct task_struct *child, struct switch_stack *child_stack,
unsigned long user_rbs_end, unsigned long addr, long val)
{
unsigned long *bspstore, *krbs, regnum, *laddr;
unsigned long *urbs_end = (long *) user_rbs_end;
struct pt_regs *child_regs;
laddr = (unsigned long *) addr;
child_regs = task_pt_regs(child);
bspstore = (unsigned long *) child_regs->ar_bspstore;
krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
if (on_kernel_rbs(addr, (unsigned long) bspstore,
(unsigned long) urbs_end))
{
/*
* Attempt to write the RBS in an area that's actually
* on the kernel RBS => write the corresponding bits
* in the kernel RBS.
*/
if (ia64_rse_is_rnat_slot(laddr))
put_rnat(child, child_stack, krbs, laddr, val,
urbs_end);
else {
if (laddr < urbs_end) {
regnum = ia64_rse_num_regs(bspstore, laddr);
*ia64_rse_skip_regs(krbs, regnum) = val;
}
}
} else if (access_process_vm(child, addr, &val, sizeof(val),
FOLL_FORCE | FOLL_WRITE)
!= sizeof(val))
return -EIO;
return 0;
}
/*
* Calculate the address of the end of the user-level register backing
* store. This is the address that would have been stored in ar.bsp
* if the user had executed a "cover" instruction right before
* entering the kernel. If CFMP is not NULL, it is used to return the
* "current frame mask" that was active at the time the kernel was
* entered.
*/
unsigned long
ia64_get_user_rbs_end (struct task_struct *child, struct pt_regs *pt,
unsigned long *cfmp)
{
unsigned long *krbs, *bspstore, cfm = pt->cr_ifs;
long ndirty;
krbs = (unsigned long *) child + IA64_RBS_OFFSET/8;
bspstore = (unsigned long *) pt->ar_bspstore;
ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
if (in_syscall(pt))
ndirty += (cfm & 0x7f);
else
cfm &= ~(1UL << 63); /* clear valid bit */
if (cfmp)
*cfmp = cfm;
return (unsigned long) ia64_rse_skip_regs(bspstore, ndirty);
}
/*
* Synchronize (i.e, write) the RSE backing store living in kernel
* space to the VM of the CHILD task. SW and PT are the pointers to
* the switch_stack and pt_regs structures, respectively.
* USER_RBS_END is the user-level address at which the backing store
* ends.
*/
long
ia64_sync_user_rbs (struct task_struct *child, struct switch_stack *sw,
unsigned long user_rbs_start, unsigned long user_rbs_end)
{
unsigned long addr, val;
long ret;
/* now copy word for word from kernel rbs to user rbs: */
for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
ret = ia64_peek(child, sw, user_rbs_end, addr, &val);
if (ret < 0)
return ret;
if (access_process_vm(child, addr, &val, sizeof(val),
FOLL_FORCE | FOLL_WRITE)
!= sizeof(val))
return -EIO;
}
return 0;
}
static long
ia64_sync_kernel_rbs (struct task_struct *child, struct switch_stack *sw,
unsigned long user_rbs_start, unsigned long user_rbs_end)
{
unsigned long addr, val;
long ret;
/* now copy word for word from user rbs to kernel rbs: */
for (addr = user_rbs_start; addr < user_rbs_end; addr += 8) {
if (access_process_vm(child, addr, &val, sizeof(val),
FOLL_FORCE)
!= sizeof(val))
return -EIO;
ret = ia64_poke(child, sw, user_rbs_end, addr, val);
if (ret < 0)
return ret;
}
return 0;
}
typedef long (*syncfunc_t)(struct task_struct *, struct switch_stack *,
unsigned long, unsigned long);
static void do_sync_rbs(struct unw_frame_info *info, void *arg)
{
struct pt_regs *pt;
unsigned long urbs_end;
syncfunc_t fn = arg;
if (unw_unwind_to_user(info) < 0)
return;
pt = task_pt_regs(info->task);
urbs_end = ia64_get_user_rbs_end(info->task, pt, NULL);
fn(info->task, info->sw, pt->ar_bspstore, urbs_end);
}
/*
* when a thread is stopped (ptraced), debugger might change thread's user
* stack (change memory directly), and we must avoid the RSE stored in kernel
* to override user stack (user space's RSE is newer than kernel's in the
* case). To workaround the issue, we copy kernel RSE to user RSE before the
* task is stopped, so user RSE has updated data. we then copy user RSE to
* kernel after the task is resummed from traced stop and kernel will use the
* newer RSE to return to user. TIF_RESTORE_RSE is the flag to indicate we need
* synchronize user RSE to kernel.
*/
void ia64_ptrace_stop(void)
{
if (test_and_set_tsk_thread_flag(current, TIF_RESTORE_RSE))
return;
set_notify_resume(current);
unw_init_running(do_sync_rbs, ia64_sync_user_rbs);
}
/*
* This is called to read back the register backing store.
*/
void ia64_sync_krbs(void)
{
clear_tsk_thread_flag(current, TIF_RESTORE_RSE);
unw_init_running(do_sync_rbs, ia64_sync_kernel_rbs);
}
/*
* After PTRACE_ATTACH, a thread's register backing store area in user
* space is assumed to contain correct data whenever the thread is
* stopped. arch_ptrace_stop takes care of this on tracing stops.
* But if the child was already stopped for job control when we attach
* to it, then it might not ever get into ptrace_stop by the time we
* want to examine the user memory containing the RBS.
*/
void
ptrace_attach_sync_user_rbs (struct task_struct *child)
{
int stopped = 0;
struct unw_frame_info info;
/*
* If the child is in TASK_STOPPED, we need to change that to
* TASK_TRACED momentarily while we operate on it. This ensures
* that the child won't be woken up and return to user mode while
* we are doing the sync. (It can only be woken up for SIGKILL.)
*/
read_lock(&tasklist_lock);
if (child->sighand) {
spin_lock_irq(&child->sighand->siglock);
if (READ_ONCE(child->__state) == TASK_STOPPED &&
!test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
set_notify_resume(child);
WRITE_ONCE(child->__state, TASK_TRACED);
stopped = 1;
}
spin_unlock_irq(&child->sighand->siglock);
}
read_unlock(&tasklist_lock);
if (!stopped)
return;
unw_init_from_blocked_task(&info, child);
do_sync_rbs(&info, ia64_sync_user_rbs);
/*
* Now move the child back into TASK_STOPPED if it should be in a
* job control stop, so that SIGCONT can be used to wake it up.
*/
read_lock(&tasklist_lock);
if (child->sighand) {
spin_lock_irq(&child->sighand->siglock);
if (READ_ONCE(child->__state) == TASK_TRACED &&
(child->signal->flags & SIGNAL_STOP_STOPPED)) {
WRITE_ONCE(child->__state, TASK_STOPPED);
}
spin_unlock_irq(&child->sighand->siglock);
}
read_unlock(&tasklist_lock);
}
/*
* Write f32-f127 back to task->thread.fph if it has been modified.
*/
inline void
ia64_flush_fph (struct task_struct *task)
{
struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
/*
* Prevent migrating this task while
* we're fiddling with the FPU state
*/
preempt_disable();
if (ia64_is_local_fpu_owner(task) && psr->mfh) {
psr->mfh = 0;
task->thread.flags |= IA64_THREAD_FPH_VALID;
ia64_save_fpu(&task->thread.fph[0]);
}
preempt_enable();
}
/*
* Sync the fph state of the task so that it can be manipulated
* through thread.fph. If necessary, f32-f127 are written back to
* thread.fph or, if the fph state hasn't been used before, thread.fph
* is cleared to zeroes. Also, access to f32-f127 is disabled to
* ensure that the task picks up the state from thread.fph when it
* executes again.
*/
void
ia64_sync_fph (struct task_struct *task)
{
struct ia64_psr *psr = ia64_psr(task_pt_regs(task));
ia64_flush_fph(task);
if (!(task->thread.flags & IA64_THREAD_FPH_VALID)) {
task->thread.flags |= IA64_THREAD_FPH_VALID;
memset(&task->thread.fph, 0, sizeof(task->thread.fph));
}
ia64_drop_fpu(task);
psr->dfh = 1;
}
/*
* Change the machine-state of CHILD such that it will return via the normal
* kernel exit-path, rather than the syscall-exit path.
*/
static void
convert_to_non_syscall (struct task_struct *child, struct pt_regs *pt,
unsigned long cfm)
{
struct unw_frame_info info, prev_info;
unsigned long ip, sp, pr;
unw_init_from_blocked_task(&info, child);
while (1) {
prev_info = info;
if (unw_unwind(&info) < 0)
return;
unw_get_sp(&info, &sp);
if ((long)((unsigned long)child + IA64_STK_OFFSET - sp)
< IA64_PT_REGS_SIZE) {
dprintk("ptrace.%s: ran off the top of the kernel "
"stack\n", __func__);
return;
}
if (unw_get_pr (&prev_info, &pr) < 0) {
unw_get_rp(&prev_info, &ip);
dprintk("ptrace.%s: failed to read "
"predicate register (ip=0x%lx)\n",
__func__, ip);
return;
}
if (unw_is_intr_frame(&info)
&& (pr & (1UL << PRED_USER_STACK)))
break;
}
/*
* Note: at the time of this call, the target task is blocked
* in notify_resume_user() and by clearling PRED_LEAVE_SYSCALL
* (aka, "pLvSys") we redirect execution from
* .work_pending_syscall_end to .work_processed_kernel.
*/
unw_get_pr(&prev_info, &pr);
pr &= ~((1UL << PRED_SYSCALL) | (1UL << PRED_LEAVE_SYSCALL));
pr |= (1UL << PRED_NON_SYSCALL);
unw_set_pr(&prev_info, pr);
pt->cr_ifs = (1UL << 63) | cfm;
/*
* Clear the memory that is NOT written on syscall-entry to
* ensure we do not leak kernel-state to user when execution
* resumes.
*/
pt->r2 = 0;
pt->r3 = 0;
pt->r14 = 0;
memset(&pt->r16, 0, 16*8); /* clear r16-r31 */
memset(&pt->f6, 0, 6*16); /* clear f6-f11 */
pt->b7 = 0;
pt->ar_ccv = 0;
pt->ar_csd = 0;
pt->ar_ssd = 0;
}
static int
access_nat_bits (struct task_struct *child, struct pt_regs *pt,
struct unw_frame_info *info,
unsigned long *data, int write_access)
{
unsigned long regnum, nat_bits, scratch_unat, dummy = 0;
char nat = 0;
if (write_access) {
nat_bits = *data;
scratch_unat = ia64_put_scratch_nat_bits(pt, nat_bits);
if (unw_set_ar(info, UNW_AR_UNAT, scratch_unat) < 0) {
dprintk("ptrace: failed to set ar.unat\n");
return -1;
}
for (regnum = 4; regnum <= 7; ++regnum) {
unw_get_gr(info, regnum, &dummy, &nat);
unw_set_gr(info, regnum, dummy,
(nat_bits >> regnum) & 1);
}
} else {
if (unw_get_ar(info, UNW_AR_UNAT, &scratch_unat) < 0) {
dprintk("ptrace: failed to read ar.unat\n");
return -1;
}
nat_bits = ia64_get_scratch_nat_bits(pt, scratch_unat);
for (regnum = 4; regnum <= 7; ++regnum) {
unw_get_gr(info, regnum, &dummy, &nat);
nat_bits |= (nat != 0) << regnum;
}
*data = nat_bits;
}
return 0;
}
static int
access_elf_reg(struct task_struct *target, struct unw_frame_info *info,
unsigned long addr, unsigned long *data, int write_access);
static long
ptrace_getregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
{
unsigned long psr, ec, lc, rnat, bsp, cfm, nat_bits, val;
struct unw_frame_info info;
struct ia64_fpreg fpval;
struct switch_stack *sw;
struct pt_regs *pt;
long ret, retval = 0;
char nat = 0;
int i;
if (!access_ok(ppr, sizeof(struct pt_all_user_regs)))
return -EIO;
pt = task_pt_regs(child);
sw = (struct switch_stack *) (child->thread.ksp + 16);
unw_init_from_blocked_task(&info, child);
if (unw_unwind_to_user(&info) < 0) {
return -EIO;
}
if (((unsigned long) ppr & 0x7) != 0) {
dprintk("ptrace:unaligned register address %p\n", ppr);
return -EIO;
}
if (access_elf_reg(child, &info, ELF_CR_IPSR_OFFSET, &psr, 0) < 0 ||
access_elf_reg(child, &info, ELF_AR_EC_OFFSET, &ec, 0) < 0 ||
access_elf_reg(child, &info, ELF_AR_LC_OFFSET, &lc, 0) < 0 ||
access_elf_reg(child, &info, ELF_AR_RNAT_OFFSET, &rnat, 0) < 0 ||
access_elf_reg(child, &info, ELF_AR_BSP_OFFSET, &bsp, 0) < 0 ||
access_elf_reg(child, &info, ELF_CFM_OFFSET, &cfm, 0) < 0 ||
access_elf_reg(child, &info, ELF_NAT_OFFSET, &nat_bits, 0) < 0)
return -EIO;
/* control regs */
retval |= __put_user(pt->cr_iip, &ppr->cr_iip);
retval |= __put_user(psr, &ppr->cr_ipsr);
/* app regs */
retval |= __put_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
retval |= __put_user(pt->ar_rsc, &ppr->ar[PT_AUR_RSC]);
retval |= __put_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
retval |= __put_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
retval |= __put_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
retval |= __put_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
retval |= __put_user(ec, &ppr->ar[PT_AUR_EC]);
retval |= __put_user(lc, &ppr->ar[PT_AUR_LC]);
retval |= __put_user(rnat, &ppr->ar[PT_AUR_RNAT]);
retval |= __put_user(bsp, &ppr->ar[PT_AUR_BSP]);
retval |= __put_user(cfm, &ppr->cfm);
/* gr1-gr3 */
retval |= __copy_to_user(&ppr->gr[1], &pt->r1, sizeof(long));
retval |= __copy_to_user(&ppr->gr[2], &pt->r2, sizeof(long) *2);
/* gr4-gr7 */
for (i = 4; i < 8; i++) {
if (unw_access_gr(&info, i, &val, &nat, 0) < 0)
return -EIO;
retval |= __put_user(val, &ppr->gr[i]);
}
/* gr8-gr11 */
retval |= __copy_to_user(&ppr->gr[8], &pt->r8, sizeof(long) * 4);
/* gr12-gr15 */
retval |= __copy_to_user(&ppr->gr[12], &pt->r12, sizeof(long) * 2);
retval |= __copy_to_user(&ppr->gr[14], &pt->r14, sizeof(long));
retval |= __copy_to_user(&ppr->gr[15], &pt->r15, sizeof(long));
/* gr16-gr31 */
retval |= __copy_to_user(&ppr->gr[16], &pt->r16, sizeof(long) * 16);
/* b0 */
retval |= __put_user(pt->b0, &ppr->br[0]);
/* b1-b5 */
for (i = 1; i < 6; i++) {
if (unw_access_br(&info, i, &val, 0) < 0)
return -EIO;
__put_user(val, &ppr->br[i]);
}
/* b6-b7 */
retval |= __put_user(pt->b6, &ppr->br[6]);
retval |= __put_user(pt->b7, &ppr->br[7]);
/* fr2-fr5 */
for (i = 2; i < 6; i++) {
if (unw_get_fr(&info, i, &fpval) < 0)
return -EIO;
retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
}
/* fr6-fr11 */
retval |= __copy_to_user(&ppr->fr[6], &pt->f6,
sizeof(struct ia64_fpreg) * 6);
/* fp scratch regs(12-15) */
retval |= __copy_to_user(&ppr->fr[12], &sw->f12,
sizeof(struct ia64_fpreg) * 4);
/* fr16-fr31 */
for (i = 16; i < 32; i++) {
if (unw_get_fr(&info, i, &fpval) < 0)
return -EIO;
retval |= __copy_to_user(&ppr->fr[i], &fpval, sizeof (fpval));
}
/* fph */
ia64_flush_fph(child);
retval |= __copy_to_user(&ppr->fr[32], &child->thread.fph,
sizeof(ppr->fr[32]) * 96);
/* preds */
retval |= __put_user(pt->pr, &ppr->pr);
/* nat bits */
retval |= __put_user(nat_bits, &ppr->nat);
ret = retval ? -EIO : 0;
return ret;
}
static long
ptrace_setregs (struct task_struct *child, struct pt_all_user_regs __user *ppr)
{
unsigned long psr, rsc, ec, lc, rnat, bsp, cfm, nat_bits, val = 0;
struct unw_frame_info info;
struct switch_stack *sw;
struct ia64_fpreg fpval;
struct pt_regs *pt;
long retval = 0;
int i;
memset(&fpval, 0, sizeof(fpval));
if (!access_ok(ppr, sizeof(struct pt_all_user_regs)))
return -EIO;
pt = task_pt_regs(child);
sw = (struct switch_stack *) (child->thread.ksp + 16);
unw_init_from_blocked_task(&info, child);
if (unw_unwind_to_user(&info) < 0) {
return -EIO;
}
if (((unsigned long) ppr & 0x7) != 0) {
dprintk("ptrace:unaligned register address %p\n", ppr);
return -EIO;
}
/* control regs */
retval |= __get_user(pt->cr_iip, &ppr->cr_iip);
retval |= __get_user(psr, &ppr->cr_ipsr);
/* app regs */
retval |= __get_user(pt->ar_pfs, &ppr->ar[PT_AUR_PFS]);
retval |= __get_user(rsc, &ppr->ar[PT_AUR_RSC]);
retval |= __get_user(pt->ar_bspstore, &ppr->ar[PT_AUR_BSPSTORE]);
retval |= __get_user(pt->ar_unat, &ppr->ar[PT_AUR_UNAT]);
retval |= __get_user(pt->ar_ccv, &ppr->ar[PT_AUR_CCV]);
retval |= __get_user(pt->ar_fpsr, &ppr->ar[PT_AUR_FPSR]);
retval |= __get_user(ec, &ppr->ar[PT_AUR_EC]);
retval |= __get_user(lc, &ppr->ar[PT_AUR_LC]);
retval |= __get_user(rnat, &ppr->ar[PT_AUR_RNAT]);
retval |= __get_user(bsp, &ppr->ar[PT_AUR_BSP]);
retval |= __get_user(cfm, &ppr->cfm);
/* gr1-gr3 */
retval |= __copy_from_user(&pt->r1, &ppr->gr[1], sizeof(long));
retval |= __copy_from_user(&pt->r2, &ppr->gr[2], sizeof(long) * 2);
/* gr4-gr7 */
for (i = 4; i < 8; i++) {
retval |= __get_user(val, &ppr->gr[i]);
/* NaT bit will be set via PT_NAT_BITS: */
if (unw_set_gr(&info, i, val, 0) < 0)
return -EIO;
}
/* gr8-gr11 */
retval |= __copy_from_user(&pt->r8, &ppr->gr[8], sizeof(long) * 4);
/* gr12-gr15 */
retval |= __copy_from_user(&pt->r12, &ppr->gr[12], sizeof(long) * 2);
retval |= __copy_from_user(&pt->r14, &ppr->gr[14], sizeof(long));
retval |= __copy_from_user(&pt->r15, &ppr->gr[15], sizeof(long));
/* gr16-gr31 */
retval |= __copy_from_user(&pt->r16, &ppr->gr[16], sizeof(long) * 16);
/* b0 */
retval |= __get_user(pt->b0, &ppr->br[0]);
/* b1-b5 */
for (i = 1; i < 6; i++) {
retval |= __get_user(val, &ppr->br[i]);
unw_set_br(&info, i, val);
}
/* b6-b7 */
retval |= __get_user(pt->b6, &ppr->br[6]);
retval |= __get_user(pt->b7, &ppr->br[7]);
/* fr2-fr5 */
for (i = 2; i < 6; i++) {
retval |= __copy_from_user(&fpval, &ppr->fr[i], sizeof(fpval));
if (unw_set_fr(&info, i, fpval) < 0)
return -EIO;
}
/* fr6-fr11 */
retval |= __copy_from_user(&pt->f6, &ppr->fr[6],
sizeof(ppr->fr[6]) * 6);
/* fp scratch regs(12-15) */
retval |= __copy_from_user(&sw->f12, &ppr->fr[12],
sizeof(ppr->fr[12]) * 4);
/* fr16-fr31 */
for (i = 16; i < 32; i++) {
retval |= __copy_from_user(&fpval, &ppr->fr[i],
sizeof(fpval));
if (unw_set_fr(&info, i, fpval) < 0)
return -EIO;
}
/* fph */
ia64_sync_fph(child);
retval |= __copy_from_user(&child->thread.fph, &ppr->fr[32],
sizeof(ppr->fr[32]) * 96);
/* preds */
retval |= __get_user(pt->pr, &ppr->pr);
/* nat bits */
retval |= __get_user(nat_bits, &ppr->nat);
retval |= access_elf_reg(child, &info, ELF_CR_IPSR_OFFSET, &psr, 1);
retval |= access_elf_reg(child, &info, ELF_AR_RSC_OFFSET, &rsc, 1);
retval |= access_elf_reg(child, &info, ELF_AR_EC_OFFSET, &ec, 1);
retval |= access_elf_reg(child, &info, ELF_AR_LC_OFFSET, &lc, 1);
retval |= access_elf_reg(child, &info, ELF_AR_RNAT_OFFSET, &rnat, 1);
retval |= access_elf_reg(child, &info, ELF_AR_BSP_OFFSET, &bsp, 1);
retval |= access_elf_reg(child, &info, ELF_CFM_OFFSET, &cfm, 1);
retval |= access_elf_reg(child, &info, ELF_NAT_OFFSET, &nat_bits, 1);
return retval ? -EIO : 0;
}
void
user_enable_single_step (struct task_struct *child)
{
struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
set_tsk_thread_flag(child, TIF_SINGLESTEP);
child_psr->ss = 1;
}
void
user_enable_block_step (struct task_struct *child)
{
struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
set_tsk_thread_flag(child, TIF_SINGLESTEP);
child_psr->tb = 1;
}
void
user_disable_single_step (struct task_struct *child)
{
struct ia64_psr *child_psr = ia64_psr(task_pt_regs(child));
/* make sure the single step/taken-branch trap bits are not set: */
clear_tsk_thread_flag(child, TIF_SINGLESTEP);
child_psr->ss = 0;
child_psr->tb = 0;
}
/*
* Called by kernel/ptrace.c when detaching..
*
* Make sure the single step bit is not set.
*/
void
ptrace_disable (struct task_struct *child)
{
user_disable_single_step(child);
}
static int
access_uarea (struct task_struct *child, unsigned long addr,
unsigned long *data, int write_access);
long
arch_ptrace (struct task_struct *child, long request,
unsigned long addr, unsigned long data)
{
switch (request) {
case PTRACE_PEEKTEXT:
case PTRACE_PEEKDATA:
/* read word at location addr */
if (ptrace_access_vm(child, addr, &data, sizeof(data),
FOLL_FORCE)
!= sizeof(data))
return -EIO;
/* ensure return value is not mistaken for error code */
force_successful_syscall_return();
return data;
/* PTRACE_POKETEXT and PTRACE_POKEDATA is handled
* by the generic ptrace_request().
*/
case PTRACE_PEEKUSR:
/* read the word at addr in the USER area */
if (access_uarea(child, addr, &data, 0) < 0)
return -EIO;
/* ensure return value is not mistaken for error code */
force_successful_syscall_return();
return data;
case PTRACE_POKEUSR:
/* write the word at addr in the USER area */
if (access_uarea(child, addr, &data, 1) < 0)
return -EIO;
return 0;
case PTRACE_OLD_GETSIGINFO:
/* for backwards-compatibility */
return ptrace_request(child, PTRACE_GETSIGINFO, addr, data);
case PTRACE_OLD_SETSIGINFO:
/* for backwards-compatibility */
return ptrace_request(child, PTRACE_SETSIGINFO, addr, data);
case PTRACE_GETREGS:
return ptrace_getregs(child,
(struct pt_all_user_regs __user *) data);
case PTRACE_SETREGS:
return ptrace_setregs(child,
(struct pt_all_user_regs __user *) data);
default:
return ptrace_request(child, request, addr, data);
}
}
/* "asmlinkage" so the input arguments are preserved... */
asmlinkage long
syscall_trace_enter (long arg0, long arg1, long arg2, long arg3,
long arg4, long arg5, long arg6, long arg7,
struct pt_regs regs)
{
if (test_thread_flag(TIF_SYSCALL_TRACE))
if (tracehook_report_syscall_entry(&regs))
return -ENOSYS;
/* copy user rbs to kernel rbs */
if (test_thread_flag(TIF_RESTORE_RSE))
ia64_sync_krbs();
audit_syscall_entry(regs.r15, arg0, arg1, arg2, arg3);
return 0;
}
/* "asmlinkage" so the input arguments are preserved... */
asmlinkage void
syscall_trace_leave (long arg0, long arg1, long arg2, long arg3,
long arg4, long arg5, long arg6, long arg7,
struct pt_regs regs)
{
int step;
audit_syscall_exit(&regs);
step = test_thread_flag(TIF_SINGLESTEP);
if (step || test_thread_flag(TIF_SYSCALL_TRACE))
tracehook_report_syscall_exit(&regs, step);
/* copy user rbs to kernel rbs */
if (test_thread_flag(TIF_RESTORE_RSE))
ia64_sync_krbs();
}
/* Utrace implementation starts here */
struct regset_get {
void *kbuf;
void __user *ubuf;
};
struct regset_set {
const void *kbuf;
const void __user *ubuf;
};
struct regset_getset {
struct task_struct *target;
const struct user_regset *regset;
union {
struct regset_get get;
struct regset_set set;
} u;
unsigned int pos;
unsigned int count;
int ret;
};
static const ptrdiff_t pt_offsets[32] =
{
#define R(n) offsetof(struct pt_regs, r##n)
[0] = -1, R(1), R(2), R(3),
[4] = -1, [5] = -1, [6] = -1, [7] = -1,
R(8), R(9), R(10), R(11), R(12), R(13), R(14), R(15),
R(16), R(17), R(18), R(19), R(20), R(21), R(22), R(23),
R(24), R(25), R(26), R(27), R(28), R(29), R(30), R(31),
#undef R
};
static int
access_elf_gpreg(struct task_struct *target, struct unw_frame_info *info,
unsigned long addr, unsigned long *data, int write_access)
{
struct pt_regs *pt = task_pt_regs(target);
unsigned reg = addr / sizeof(unsigned long);
ptrdiff_t d = pt_offsets[reg];
if (d >= 0) {
unsigned long *ptr = (void *)pt + d;
if (write_access)
*ptr = *data;
else
*data = *ptr;
return 0;
} else {
char nat = 0;
if (write_access) {
/* read NaT bit first: */
unsigned long dummy;
int ret = unw_get_gr(info, reg, &dummy, &nat);
if (ret < 0)
return ret;
}
return unw_access_gr(info, reg, data, &nat, write_access);
}
}
static int
access_elf_breg(struct task_struct *target, struct unw_frame_info *info,
unsigned long addr, unsigned long *data, int write_access)
{
struct pt_regs *pt;
unsigned long *ptr = NULL;
pt = task_pt_regs(target);
switch (addr) {
case ELF_BR_OFFSET(0):
ptr = &pt->b0;
break;
case ELF_BR_OFFSET(1) ... ELF_BR_OFFSET(5):
return unw_access_br(info, (addr - ELF_BR_OFFSET(0))/8,
data, write_access);
case ELF_BR_OFFSET(6):
ptr = &pt->b6;
break;
case ELF_BR_OFFSET(7):
ptr = &pt->b7;
}
if (write_access)
*ptr = *data;
else
*data = *ptr;
return 0;
}
static int
access_elf_areg(struct task_struct *target, struct unw_frame_info *info,
unsigned long addr, unsigned long *data, int write_access)
{
struct pt_regs *pt;
unsigned long cfm, urbs_end;
unsigned long *ptr = NULL;
pt = task_pt_regs(target);
if (addr >= ELF_AR_RSC_OFFSET && addr <= ELF_AR_SSD_OFFSET) {
switch (addr) {
case ELF_AR_RSC_OFFSET:
/* force PL3 */
if (write_access)
pt->ar_rsc = *data | (3 << 2);
else
*data = pt->ar_rsc;
return 0;
case ELF_AR_BSP_OFFSET:
/*
* By convention, we use PT_AR_BSP to refer to
* the end of the user-level backing store.
* Use ia64_rse_skip_regs(PT_AR_BSP, -CFM.sof)
* to get the real value of ar.bsp at the time
* the kernel was entered.
*
* Furthermore, when changing the contents of
* PT_AR_BSP (or PT_CFM) while the task is
* blocked in a system call, convert the state
* so that the non-system-call exit
* path is used. This ensures that the proper
* state will be picked up when resuming
* execution. However, it *also* means that
* once we write PT_AR_BSP/PT_CFM, it won't be
* possible to modify the syscall arguments of
* the pending system call any longer. This
* shouldn't be an issue because modifying
* PT_AR_BSP/PT_CFM generally implies that
* we're either abandoning the pending system
* call or that we defer it's re-execution
* (e.g., due to GDB doing an inferior
* function call).
*/
urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
if (write_access) {
if (*data != urbs_end) {
if (in_syscall(pt))
convert_to_non_syscall(target,
pt,
cfm);
/*
* Simulate user-level write
* of ar.bsp:
*/
pt->loadrs = 0;
pt->ar_bspstore = *data;
}
} else
*data = urbs_end;
return 0;
case ELF_AR_BSPSTORE_OFFSET:
ptr = &pt->ar_bspstore;
break;
case ELF_AR_RNAT_OFFSET:
ptr = &pt->ar_rnat;
break;
case ELF_AR_CCV_OFFSET:
ptr = &pt->ar_ccv;
break;
case ELF_AR_UNAT_OFFSET:
ptr = &pt->ar_unat;
break;
case ELF_AR_FPSR_OFFSET:
ptr = &pt->ar_fpsr;
break;
case ELF_AR_PFS_OFFSET:
ptr = &pt->ar_pfs;
break;
case ELF_AR_LC_OFFSET:
return unw_access_ar(info, UNW_AR_LC, data,
write_access);
case ELF_AR_EC_OFFSET:
return unw_access_ar(info, UNW_AR_EC, data,
write_access);
case ELF_AR_CSD_OFFSET:
ptr = &pt->ar_csd;
break;
case ELF_AR_SSD_OFFSET:
ptr = &pt->ar_ssd;
}
} else if (addr >= ELF_CR_IIP_OFFSET && addr <= ELF_CR_IPSR_OFFSET) {
switch (addr) {
case ELF_CR_IIP_OFFSET:
ptr = &pt->cr_iip;
break;
case ELF_CFM_OFFSET:
urbs_end = ia64_get_user_rbs_end(target, pt, &cfm);
if (write_access) {
if (((cfm ^ *data) & PFM_MASK) != 0) {
if (in_syscall(pt))
convert_to_non_syscall(target,
pt,
cfm);
pt->cr_ifs = ((pt->cr_ifs & ~PFM_MASK)
| (*data & PFM_MASK));
}
} else
*data = cfm;
return 0;
case ELF_CR_IPSR_OFFSET:
if (write_access) {
unsigned long tmp = *data;
/* psr.ri==3 is a reserved value: SDM 2:25 */
if ((tmp & IA64_PSR_RI) == IA64_PSR_RI)
tmp &= ~IA64_PSR_RI;
pt->cr_ipsr = ((tmp & IPSR_MASK)
| (pt->cr_ipsr & ~IPSR_MASK));
} else
*data = (pt->cr_ipsr & IPSR_MASK);
return 0;
}
} else if (addr == ELF_NAT_OFFSET)
return access_nat_bits(target, pt, info,
data, write_access);
else if (addr == ELF_PR_OFFSET)
ptr = &pt->pr;
else
return -1;
if (write_access)
*ptr = *data;
else
*data = *ptr;
return 0;
}
static int
access_elf_reg(struct task_struct *target, struct unw_frame_info *info,
unsigned long addr, unsigned long *data, int write_access)
{
if (addr >= ELF_GR_OFFSET(1) && addr <= ELF_GR_OFFSET(31))
return access_elf_gpreg(target, info, addr, data, write_access);
else if (addr >= ELF_BR_OFFSET(0) && addr <= ELF_BR_OFFSET(7))
return access_elf_breg(target, info, addr, data, write_access);
else
return access_elf_areg(target, info, addr, data, write_access);
}
struct regset_membuf {
struct membuf to;
int ret;
};
static void do_gpregs_get(struct unw_frame_info *info, void *arg)
{
struct regset_membuf *dst = arg;
struct membuf to = dst->to;
unsigned int n;
elf_greg_t reg;
if (unw_unwind_to_user(info) < 0)
return;
/*
* coredump format:
* r0-r31
* NaT bits (for r0-r31; bit N == 1 iff rN is a NaT)
* predicate registers (p0-p63)
* b0-b7
* ip cfm user-mask
* ar.rsc ar.bsp ar.bspstore ar.rnat
* ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec
*/
/* Skip r0 */
membuf_zero(&to, 8);
for (n = 8; to.left && n < ELF_AR_END_OFFSET; n += 8) {
if (access_elf_reg(info->task, info, n, &reg, 0) < 0) {
dst->ret = -EIO;
return;
}
membuf_store(&to, reg);
}
}
static void do_gpregs_set(struct unw_frame_info *info, void *arg)
{
struct regset_getset *dst = arg;
if (unw_unwind_to_user(info) < 0)
return;
if (!dst->count)
return;
/* Skip r0 */
if (dst->pos < ELF_GR_OFFSET(1)) {
dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
&dst->u.set.kbuf,
&dst->u.set.ubuf,
0, ELF_GR_OFFSET(1));
if (dst->ret)
return;
}
while (dst->count && dst->pos < ELF_AR_END_OFFSET) {
unsigned int n, from, to;
elf_greg_t tmp[16];
from = dst->pos;
to = from + sizeof(tmp);
if (to > ELF_AR_END_OFFSET)
to = ELF_AR_END_OFFSET;
/* get up to 16 values */
dst->ret = user_regset_copyin(&dst->pos, &dst->count,
&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
from, to);
if (dst->ret)
return;
/* now copy them into registers */
for (n = 0; from < dst->pos; from += sizeof(elf_greg_t), n++)
if (access_elf_reg(dst->target, info, from,
&tmp[n], 1) < 0) {
dst->ret = -EIO;
return;
}
}
}
#define ELF_FP_OFFSET(i) (i * sizeof(elf_fpreg_t))
static void do_fpregs_get(struct unw_frame_info *info, void *arg)
{
struct task_struct *task = info->task;
struct regset_membuf *dst = arg;
struct membuf to = dst->to;
elf_fpreg_t reg;
unsigned int n;
if (unw_unwind_to_user(info) < 0)
return;
/* Skip pos 0 and 1 */
membuf_zero(&to, 2 * sizeof(elf_fpreg_t));
/* fr2-fr31 */
for (n = 2; to.left && n < 32; n++) {
if (unw_get_fr(info, n, &reg)) {
dst->ret = -EIO;
return;
}
membuf_write(&to, &reg, sizeof(reg));
}
/* fph */
if (!to.left)
return;
ia64_flush_fph(task);
if (task->thread.flags & IA64_THREAD_FPH_VALID)
membuf_write(&to, &task->thread.fph, 96 * sizeof(reg));
else
membuf_zero(&to, 96 * sizeof(reg));
}
static void do_fpregs_set(struct unw_frame_info *info, void *arg)
{
struct regset_getset *dst = arg;
elf_fpreg_t fpreg, tmp[30];
int index, start, end;
if (unw_unwind_to_user(info) < 0)
return;
/* Skip pos 0 and 1 */
if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(2)) {
dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
&dst->u.set.kbuf,
&dst->u.set.ubuf,
0, ELF_FP_OFFSET(2));
if (dst->count == 0 || dst->ret)
return;
}
/* fr2-fr31 */
if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(32)) {
start = dst->pos;
end = min(((unsigned int)ELF_FP_OFFSET(32)),
dst->pos + dst->count);
dst->ret = user_regset_copyin(&dst->pos, &dst->count,
&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
ELF_FP_OFFSET(2), ELF_FP_OFFSET(32));
if (dst->ret)
return;
if (start & 0xF) { /* only write high part */
if (unw_get_fr(info, start / sizeof(elf_fpreg_t),
&fpreg)) {
dst->ret = -EIO;
return;
}
tmp[start / sizeof(elf_fpreg_t) - 2].u.bits[0]
= fpreg.u.bits[0];
start &= ~0xFUL;
}
if (end & 0xF) { /* only write low part */
if (unw_get_fr(info, end / sizeof(elf_fpreg_t),
&fpreg)) {
dst->ret = -EIO;
return;
}
tmp[end / sizeof(elf_fpreg_t) - 2].u.bits[1]
= fpreg.u.bits[1];
end = (end + 0xF) & ~0xFUL;
}
for ( ; start < end ; start += sizeof(elf_fpreg_t)) {
index = start / sizeof(elf_fpreg_t);
if (unw_set_fr(info, index, tmp[index - 2])) {
dst->ret = -EIO;
return;
}
}
if (dst->ret || dst->count == 0)
return;
}
/* fph */
if (dst->count > 0 && dst->pos < ELF_FP_OFFSET(128)) {
ia64_sync_fph(dst->target);
dst->ret = user_regset_copyin(&dst->pos, &dst->count,
&dst->u.set.kbuf,
&dst->u.set.ubuf,
&dst->target->thread.fph,
ELF_FP_OFFSET(32), -1);
}
}
static void
unwind_and_call(void (*call)(struct unw_frame_info *, void *),
struct task_struct *target, void *data)
{
if (target == current)
unw_init_running(call, data);
else {
struct unw_frame_info info;
memset(&info, 0, sizeof(info));
unw_init_from_blocked_task(&info, target);
(*call)(&info, data);
}
}
static int
do_regset_call(void (*call)(struct unw_frame_info *, void *),
struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
struct regset_getset info = { .target = target, .regset = regset,
.pos = pos, .count = count,
.u.set = { .kbuf = kbuf, .ubuf = ubuf },
.ret = 0 };
unwind_and_call(call, target, &info);
return info.ret;
}
static int
gpregs_get(struct task_struct *target,
const struct user_regset *regset,
struct membuf to)
{
struct regset_membuf info = {.to = to};
unwind_and_call(do_gpregs_get, target, &info);
return info.ret;
}
static int gpregs_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
return do_regset_call(do_gpregs_set, target, regset, pos, count,
kbuf, ubuf);
}
static void do_gpregs_writeback(struct unw_frame_info *info, void *arg)
{
do_sync_rbs(info, ia64_sync_user_rbs);
}
/*
* This is called to write back the register backing store.
* ptrace does this before it stops, so that a tracer reading the user
* memory after the thread stops will get the current register data.
*/
static int
gpregs_writeback(struct task_struct *target,
const struct user_regset *regset,
int now)
{
if (test_and_set_tsk_thread_flag(target, TIF_RESTORE_RSE))
return 0;
set_notify_resume(target);
return do_regset_call(do_gpregs_writeback, target, regset, 0, 0,
NULL, NULL);
}
static int
fpregs_active(struct task_struct *target, const struct user_regset *regset)
{
return (target->thread.flags & IA64_THREAD_FPH_VALID) ? 128 : 32;
}
static int fpregs_get(struct task_struct *target,
const struct user_regset *regset,
struct membuf to)
{
struct regset_membuf info = {.to = to};
unwind_and_call(do_fpregs_get, target, &info);
return info.ret;
}
static int fpregs_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
return do_regset_call(do_fpregs_set, target, regset, pos, count,
kbuf, ubuf);
}
static int
access_uarea(struct task_struct *child, unsigned long addr,
unsigned long *data, int write_access)
{
unsigned int pos = -1; /* an invalid value */
unsigned long *ptr, regnum;
if ((addr & 0x7) != 0) {
dprintk("ptrace: unaligned register address 0x%lx\n", addr);
return -1;
}
if ((addr >= PT_NAT_BITS + 8 && addr < PT_F2) ||
(addr >= PT_R7 + 8 && addr < PT_B1) ||
(addr >= PT_AR_LC + 8 && addr < PT_CR_IPSR) ||
(addr >= PT_AR_SSD + 8 && addr < PT_DBR)) {
dprintk("ptrace: rejecting access to register "
"address 0x%lx\n", addr);
return -1;
}
switch (addr) {
case PT_F32 ... (PT_F127 + 15):
pos = addr - PT_F32 + ELF_FP_OFFSET(32);
break;
case PT_F2 ... (PT_F5 + 15):
pos = addr - PT_F2 + ELF_FP_OFFSET(2);
break;
case PT_F10 ... (PT_F31 + 15):
pos = addr - PT_F10 + ELF_FP_OFFSET(10);
break;
case PT_F6 ... (PT_F9 + 15):
pos = addr - PT_F6 + ELF_FP_OFFSET(6);
break;
}
if (pos != -1) {
unsigned reg = pos / sizeof(elf_fpreg_t);
int which_half = (pos / sizeof(unsigned long)) & 1;
if (reg < 32) { /* fr2-fr31 */
struct unw_frame_info info;
elf_fpreg_t fpreg;
memset(&info, 0, sizeof(info));
unw_init_from_blocked_task(&info, child);
if (unw_unwind_to_user(&info) < 0)
return 0;
if (unw_get_fr(&info, reg, &fpreg))
return -1;
if (write_access) {
fpreg.u.bits[which_half] = *data;
if (unw_set_fr(&info, reg, fpreg))
return -1;
} else {
*data = fpreg.u.bits[which_half];
}
} else { /* fph */
elf_fpreg_t *p = &child->thread.fph[reg - 32];
unsigned long *bits = &p->u.bits[which_half];
ia64_sync_fph(child);
if (write_access)
*bits = *data;
else if (child->thread.flags & IA64_THREAD_FPH_VALID)
*data = *bits;
else
*data = 0;
}
return 0;
}
switch (addr) {
case PT_NAT_BITS:
pos = ELF_NAT_OFFSET;
break;
case PT_R4 ... PT_R7:
pos = addr - PT_R4 + ELF_GR_OFFSET(4);
break;
case PT_B1 ... PT_B5:
pos = addr - PT_B1 + ELF_BR_OFFSET(1);
break;
case PT_AR_EC:
pos = ELF_AR_EC_OFFSET;
break;
case PT_AR_LC:
pos = ELF_AR_LC_OFFSET;
break;
case PT_CR_IPSR:
pos = ELF_CR_IPSR_OFFSET;
break;
case PT_CR_IIP:
pos = ELF_CR_IIP_OFFSET;
break;
case PT_CFM:
pos = ELF_CFM_OFFSET;
break;
case PT_AR_UNAT:
pos = ELF_AR_UNAT_OFFSET;
break;
case PT_AR_PFS:
pos = ELF_AR_PFS_OFFSET;
break;
case PT_AR_RSC:
pos = ELF_AR_RSC_OFFSET;
break;
case PT_AR_RNAT:
pos = ELF_AR_RNAT_OFFSET;
break;
case PT_AR_BSPSTORE:
pos = ELF_AR_BSPSTORE_OFFSET;
break;
case PT_PR:
pos = ELF_PR_OFFSET;
break;
case PT_B6:
pos = ELF_BR_OFFSET(6);
break;
case PT_AR_BSP:
pos = ELF_AR_BSP_OFFSET;
break;
case PT_R1 ... PT_R3:
pos = addr - PT_R1 + ELF_GR_OFFSET(1);
break;
case PT_R12 ... PT_R15:
pos = addr - PT_R12 + ELF_GR_OFFSET(12);
break;
case PT_R8 ... PT_R11:
pos = addr - PT_R8 + ELF_GR_OFFSET(8);
break;
case PT_R16 ... PT_R31:
pos = addr - PT_R16 + ELF_GR_OFFSET(16);
break;
case PT_AR_CCV:
pos = ELF_AR_CCV_OFFSET;
break;
case PT_AR_FPSR:
pos = ELF_AR_FPSR_OFFSET;
break;
case PT_B0:
pos = ELF_BR_OFFSET(0);
break;
case PT_B7:
pos = ELF_BR_OFFSET(7);
break;
case PT_AR_CSD:
pos = ELF_AR_CSD_OFFSET;
break;
case PT_AR_SSD:
pos = ELF_AR_SSD_OFFSET;
break;
}
if (pos != -1) {
struct unw_frame_info info;
memset(&info, 0, sizeof(info));
unw_init_from_blocked_task(&info, child);
if (unw_unwind_to_user(&info) < 0)
return 0;
return access_elf_reg(child, &info, pos, data, write_access);
}
/* access debug registers */
if (addr >= PT_IBR) {
regnum = (addr - PT_IBR) >> 3;
ptr = &child->thread.ibr[0];
} else {
regnum = (addr - PT_DBR) >> 3;
ptr = &child->thread.dbr[0];
}
if (regnum >= 8) {
dprintk("ptrace: rejecting access to register "
"address 0x%lx\n", addr);
return -1;
}
if (!(child->thread.flags & IA64_THREAD_DBG_VALID)) {
child->thread.flags |= IA64_THREAD_DBG_VALID;
memset(child->thread.dbr, 0,
sizeof(child->thread.dbr));
memset(child->thread.ibr, 0,
sizeof(child->thread.ibr));
}
ptr += regnum;
if ((regnum & 1) && write_access) {
/* don't let the user set kernel-level breakpoints: */
*ptr = *data & ~(7UL << 56);
return 0;
}
if (write_access)
*ptr = *data;
else
*data = *ptr;
return 0;
}
static const struct user_regset native_regsets[] = {
{
.core_note_type = NT_PRSTATUS,
.n = ELF_NGREG,
.size = sizeof(elf_greg_t), .align = sizeof(elf_greg_t),
.regset_get = gpregs_get, .set = gpregs_set,
.writeback = gpregs_writeback
},
{
.core_note_type = NT_PRFPREG,
.n = ELF_NFPREG,
.size = sizeof(elf_fpreg_t), .align = sizeof(elf_fpreg_t),
.regset_get = fpregs_get, .set = fpregs_set, .active = fpregs_active
},
};
static const struct user_regset_view user_ia64_view = {
.name = "ia64",
.e_machine = EM_IA_64,
.regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
};
const struct user_regset_view *task_user_regset_view(struct task_struct *tsk)
{
return &user_ia64_view;
}
struct syscall_get_set_args {
unsigned int i;
unsigned int n;
unsigned long *args;
struct pt_regs *regs;
int rw;
};
static void syscall_get_set_args_cb(struct unw_frame_info *info, void *data)
{
struct syscall_get_set_args *args = data;
struct pt_regs *pt = args->regs;
unsigned long *krbs, cfm, ndirty, nlocals, nouts;
int i, count;
if (unw_unwind_to_user(info) < 0)
return;
/*
* We get here via a few paths:
* - break instruction: cfm is shared with caller.
* syscall args are in out= regs, locals are non-empty.
* - epsinstruction: cfm is set by br.call
* locals don't exist.
*
* For both cases argguments are reachable in cfm.sof - cfm.sol.
* CFM: [ ... | sor: 17..14 | sol : 13..7 | sof : 6..0 ]
*/
cfm = pt->cr_ifs;
nlocals = (cfm >> 7) & 0x7f; /* aka sol */
nouts = (cfm & 0x7f) - nlocals; /* aka sof - sol */
krbs = (unsigned long *)info->task + IA64_RBS_OFFSET/8;
ndirty = ia64_rse_num_regs(krbs, krbs + (pt->loadrs >> 19));
count = 0;
if (in_syscall(pt))
count = min_t(int, args->n, nouts);
/* Iterate over outs. */
for (i = 0; i < count; i++) {
int j = ndirty + nlocals + i + args->i;
if (args->rw)
*ia64_rse_skip_regs(krbs, j) = args->args[i];
else
args->args[i] = *ia64_rse_skip_regs(krbs, j);
}
if (!args->rw) {
while (i < args->n) {
args->args[i] = 0;
i++;
}
}
}
void ia64_syscall_get_set_arguments(struct task_struct *task,
struct pt_regs *regs, unsigned long *args, int rw)
{
struct syscall_get_set_args data = {
.i = 0,
.n = 6,
.args = args,
.regs = regs,
.rw = rw,
};
if (task == current)
unw_init_running(syscall_get_set_args_cb, &data);
else {
struct unw_frame_info ufi;
memset(&ufi, 0, sizeof(ufi));
unw_init_from_blocked_task(&ufi, task);
syscall_get_set_args_cb(&ufi, &data);
}
}
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