alistair23-linux/arch/powerpc/kernel/ptrace.c
Michael Ellerman 2449acc534 powerpc/kernel: Enable seccomp filter
This commit enables seccomp filter on powerpc, now that we have all the
necessary pieces in place.

To support seccomp's desire to modify the syscall return value under
some circumstances, we use a different ABI to the ptrace ABI. That is we
use r3 as the syscall return value, and orig_gpr3 is the first syscall
parameter.

This means the seccomp code, or a ptracer via SECCOMP_RET_TRACE, will
see -ENOSYS preloaded in r3. This is identical to the behaviour on x86,
and allows seccomp or the ptracer to either leave the -ENOSYS or change
it to something else, as well as rejecting or not the syscall by
modifying r0.

If seccomp does not reject the syscall, we restore the register state to
match what ptrace and audit expect, ie. r3 is the first syscall
parameter again. We do this restore using orig_gpr3, which may have been
modified by seccomp, which allows seccomp to modify the first syscall
paramater and allow the syscall to proceed.

We need to #ifdef the the additional handling of r3 for seccomp, so move
it all out of line.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Kees Cook <keescook@chromium.org>
2015-07-30 14:34:44 +10:00

1884 lines
48 KiB
C

/*
* PowerPC version
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
*
* Derived from "arch/m68k/kernel/ptrace.c"
* Copyright (C) 1994 by Hamish Macdonald
* Taken from linux/kernel/ptrace.c and modified for M680x0.
* linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
*
* Modified by Cort Dougan (cort@hq.fsmlabs.com)
* and Paul Mackerras (paulus@samba.org).
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file README.legal in the main directory of
* this archive for more details.
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/regset.h>
#include <linux/tracehook.h>
#include <linux/elf.h>
#include <linux/user.h>
#include <linux/security.h>
#include <linux/signal.h>
#include <linux/seccomp.h>
#include <linux/audit.h>
#include <trace/syscall.h>
#include <linux/hw_breakpoint.h>
#include <linux/perf_event.h>
#include <linux/context_tracking.h>
#include <asm/uaccess.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/switch_to.h>
#define CREATE_TRACE_POINTS
#include <trace/events/syscalls.h>
/*
* The parameter save area on the stack is used to store arguments being passed
* to callee function and is located at fixed offset from stack pointer.
*/
#ifdef CONFIG_PPC32
#define PARAMETER_SAVE_AREA_OFFSET 24 /* bytes */
#else /* CONFIG_PPC32 */
#define PARAMETER_SAVE_AREA_OFFSET 48 /* bytes */
#endif
struct pt_regs_offset {
const char *name;
int offset;
};
#define STR(s) #s /* convert to string */
#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
#define GPR_OFFSET_NAME(num) \
{.name = STR(gpr##num), .offset = offsetof(struct pt_regs, gpr[num])}
#define REG_OFFSET_END {.name = NULL, .offset = 0}
static const struct pt_regs_offset regoffset_table[] = {
GPR_OFFSET_NAME(0),
GPR_OFFSET_NAME(1),
GPR_OFFSET_NAME(2),
GPR_OFFSET_NAME(3),
GPR_OFFSET_NAME(4),
GPR_OFFSET_NAME(5),
GPR_OFFSET_NAME(6),
GPR_OFFSET_NAME(7),
GPR_OFFSET_NAME(8),
GPR_OFFSET_NAME(9),
GPR_OFFSET_NAME(10),
GPR_OFFSET_NAME(11),
GPR_OFFSET_NAME(12),
GPR_OFFSET_NAME(13),
GPR_OFFSET_NAME(14),
GPR_OFFSET_NAME(15),
GPR_OFFSET_NAME(16),
GPR_OFFSET_NAME(17),
GPR_OFFSET_NAME(18),
GPR_OFFSET_NAME(19),
GPR_OFFSET_NAME(20),
GPR_OFFSET_NAME(21),
GPR_OFFSET_NAME(22),
GPR_OFFSET_NAME(23),
GPR_OFFSET_NAME(24),
GPR_OFFSET_NAME(25),
GPR_OFFSET_NAME(26),
GPR_OFFSET_NAME(27),
GPR_OFFSET_NAME(28),
GPR_OFFSET_NAME(29),
GPR_OFFSET_NAME(30),
GPR_OFFSET_NAME(31),
REG_OFFSET_NAME(nip),
REG_OFFSET_NAME(msr),
REG_OFFSET_NAME(ctr),
REG_OFFSET_NAME(link),
REG_OFFSET_NAME(xer),
REG_OFFSET_NAME(ccr),
#ifdef CONFIG_PPC64
REG_OFFSET_NAME(softe),
#else
REG_OFFSET_NAME(mq),
#endif
REG_OFFSET_NAME(trap),
REG_OFFSET_NAME(dar),
REG_OFFSET_NAME(dsisr),
REG_OFFSET_END,
};
/**
* regs_query_register_offset() - query register offset from its name
* @name: the name of a register
*
* regs_query_register_offset() returns the offset of a register in struct
* pt_regs from its name. If the name is invalid, this returns -EINVAL;
*/
int regs_query_register_offset(const char *name)
{
const struct pt_regs_offset *roff;
for (roff = regoffset_table; roff->name != NULL; roff++)
if (!strcmp(roff->name, name))
return roff->offset;
return -EINVAL;
}
/**
* regs_query_register_name() - query register name from its offset
* @offset: the offset of a register in struct pt_regs.
*
* regs_query_register_name() returns the name of a register from its
* offset in struct pt_regs. If the @offset is invalid, this returns NULL;
*/
const char *regs_query_register_name(unsigned int offset)
{
const struct pt_regs_offset *roff;
for (roff = regoffset_table; roff->name != NULL; roff++)
if (roff->offset == offset)
return roff->name;
return NULL;
}
/*
* does not yet catch signals sent when the child dies.
* in exit.c or in signal.c.
*/
/*
* Set of msr bits that gdb can change on behalf of a process.
*/
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
#define MSR_DEBUGCHANGE 0
#else
#define MSR_DEBUGCHANGE (MSR_SE | MSR_BE)
#endif
/*
* Max register writeable via put_reg
*/
#ifdef CONFIG_PPC32
#define PT_MAX_PUT_REG PT_MQ
#else
#define PT_MAX_PUT_REG PT_CCR
#endif
static unsigned long get_user_msr(struct task_struct *task)
{
return task->thread.regs->msr | task->thread.fpexc_mode;
}
static int set_user_msr(struct task_struct *task, unsigned long msr)
{
task->thread.regs->msr &= ~MSR_DEBUGCHANGE;
task->thread.regs->msr |= msr & MSR_DEBUGCHANGE;
return 0;
}
#ifdef CONFIG_PPC64
static int get_user_dscr(struct task_struct *task, unsigned long *data)
{
*data = task->thread.dscr;
return 0;
}
static int set_user_dscr(struct task_struct *task, unsigned long dscr)
{
task->thread.dscr = dscr;
task->thread.dscr_inherit = 1;
return 0;
}
#else
static int get_user_dscr(struct task_struct *task, unsigned long *data)
{
return -EIO;
}
static int set_user_dscr(struct task_struct *task, unsigned long dscr)
{
return -EIO;
}
#endif
/*
* We prevent mucking around with the reserved area of trap
* which are used internally by the kernel.
*/
static int set_user_trap(struct task_struct *task, unsigned long trap)
{
task->thread.regs->trap = trap & 0xfff0;
return 0;
}
/*
* Get contents of register REGNO in task TASK.
*/
int ptrace_get_reg(struct task_struct *task, int regno, unsigned long *data)
{
if ((task->thread.regs == NULL) || !data)
return -EIO;
if (regno == PT_MSR) {
*data = get_user_msr(task);
return 0;
}
if (regno == PT_DSCR)
return get_user_dscr(task, data);
if (regno < (sizeof(struct pt_regs) / sizeof(unsigned long))) {
*data = ((unsigned long *)task->thread.regs)[regno];
return 0;
}
return -EIO;
}
/*
* Write contents of register REGNO in task TASK.
*/
int ptrace_put_reg(struct task_struct *task, int regno, unsigned long data)
{
if (task->thread.regs == NULL)
return -EIO;
if (regno == PT_MSR)
return set_user_msr(task, data);
if (regno == PT_TRAP)
return set_user_trap(task, data);
if (regno == PT_DSCR)
return set_user_dscr(task, data);
if (regno <= PT_MAX_PUT_REG) {
((unsigned long *)task->thread.regs)[regno] = data;
return 0;
}
return -EIO;
}
static int gpr_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
int i, ret;
if (target->thread.regs == NULL)
return -EIO;
if (!FULL_REGS(target->thread.regs)) {
/* We have a partial register set. Fill 14-31 with bogus values */
for (i = 14; i < 32; i++)
target->thread.regs->gpr[i] = NV_REG_POISON;
}
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
target->thread.regs,
0, offsetof(struct pt_regs, msr));
if (!ret) {
unsigned long msr = get_user_msr(target);
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &msr,
offsetof(struct pt_regs, msr),
offsetof(struct pt_regs, msr) +
sizeof(msr));
}
BUILD_BUG_ON(offsetof(struct pt_regs, orig_gpr3) !=
offsetof(struct pt_regs, msr) + sizeof(long));
if (!ret)
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.regs->orig_gpr3,
offsetof(struct pt_regs, orig_gpr3),
sizeof(struct pt_regs));
if (!ret)
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
sizeof(struct pt_regs), -1);
return ret;
}
static int gpr_set(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
unsigned long reg;
int ret;
if (target->thread.regs == NULL)
return -EIO;
CHECK_FULL_REGS(target->thread.regs);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
target->thread.regs,
0, PT_MSR * sizeof(reg));
if (!ret && count > 0) {
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &reg,
PT_MSR * sizeof(reg),
(PT_MSR + 1) * sizeof(reg));
if (!ret)
ret = set_user_msr(target, reg);
}
BUILD_BUG_ON(offsetof(struct pt_regs, orig_gpr3) !=
offsetof(struct pt_regs, msr) + sizeof(long));
if (!ret)
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.regs->orig_gpr3,
PT_ORIG_R3 * sizeof(reg),
(PT_MAX_PUT_REG + 1) * sizeof(reg));
if (PT_MAX_PUT_REG + 1 < PT_TRAP && !ret)
ret = user_regset_copyin_ignore(
&pos, &count, &kbuf, &ubuf,
(PT_MAX_PUT_REG + 1) * sizeof(reg),
PT_TRAP * sizeof(reg));
if (!ret && count > 0) {
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &reg,
PT_TRAP * sizeof(reg),
(PT_TRAP + 1) * sizeof(reg));
if (!ret)
ret = set_user_trap(target, reg);
}
if (!ret)
ret = user_regset_copyin_ignore(
&pos, &count, &kbuf, &ubuf,
(PT_TRAP + 1) * sizeof(reg), -1);
return ret;
}
static int fpr_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
#ifdef CONFIG_VSX
u64 buf[33];
int i;
#endif
flush_fp_to_thread(target);
#ifdef CONFIG_VSX
/* copy to local buffer then write that out */
for (i = 0; i < 32 ; i++)
buf[i] = target->thread.TS_FPR(i);
buf[32] = target->thread.fp_state.fpscr;
return user_regset_copyout(&pos, &count, &kbuf, &ubuf, buf, 0, -1);
#else
BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
offsetof(struct thread_fp_state, fpr[32][0]));
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.fp_state, 0, -1);
#endif
}
static int fpr_set(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
#ifdef CONFIG_VSX
u64 buf[33];
int i;
#endif
flush_fp_to_thread(target);
#ifdef CONFIG_VSX
/* copy to local buffer then write that out */
i = user_regset_copyin(&pos, &count, &kbuf, &ubuf, buf, 0, -1);
if (i)
return i;
for (i = 0; i < 32 ; i++)
target->thread.TS_FPR(i) = buf[i];
target->thread.fp_state.fpscr = buf[32];
return 0;
#else
BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
offsetof(struct thread_fp_state, fpr[32][0]));
return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.fp_state, 0, -1);
#endif
}
#ifdef CONFIG_ALTIVEC
/*
* Get/set all the altivec registers vr0..vr31, vscr, vrsave, in one go.
* The transfer totals 34 quadword. Quadwords 0-31 contain the
* corresponding vector registers. Quadword 32 contains the vscr as the
* last word (offset 12) within that quadword. Quadword 33 contains the
* vrsave as the first word (offset 0) within the quadword.
*
* This definition of the VMX state is compatible with the current PPC32
* ptrace interface. This allows signal handling and ptrace to use the
* same structures. This also simplifies the implementation of a bi-arch
* (combined (32- and 64-bit) gdb.
*/
static int vr_active(struct task_struct *target,
const struct user_regset *regset)
{
flush_altivec_to_thread(target);
return target->thread.used_vr ? regset->n : 0;
}
static int vr_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
int ret;
flush_altivec_to_thread(target);
BUILD_BUG_ON(offsetof(struct thread_vr_state, vscr) !=
offsetof(struct thread_vr_state, vr[32]));
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.vr_state, 0,
33 * sizeof(vector128));
if (!ret) {
/*
* Copy out only the low-order word of vrsave.
*/
union {
elf_vrreg_t reg;
u32 word;
} vrsave;
memset(&vrsave, 0, sizeof(vrsave));
vrsave.word = target->thread.vrsave;
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &vrsave,
33 * sizeof(vector128), -1);
}
return ret;
}
static int vr_set(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
int ret;
flush_altivec_to_thread(target);
BUILD_BUG_ON(offsetof(struct thread_vr_state, vscr) !=
offsetof(struct thread_vr_state, vr[32]));
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.vr_state, 0,
33 * sizeof(vector128));
if (!ret && count > 0) {
/*
* We use only the first word of vrsave.
*/
union {
elf_vrreg_t reg;
u32 word;
} vrsave;
memset(&vrsave, 0, sizeof(vrsave));
vrsave.word = target->thread.vrsave;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &vrsave,
33 * sizeof(vector128), -1);
if (!ret)
target->thread.vrsave = vrsave.word;
}
return ret;
}
#endif /* CONFIG_ALTIVEC */
#ifdef CONFIG_VSX
/*
* Currently to set and and get all the vsx state, you need to call
* the fp and VMX calls as well. This only get/sets the lower 32
* 128bit VSX registers.
*/
static int vsr_active(struct task_struct *target,
const struct user_regset *regset)
{
flush_vsx_to_thread(target);
return target->thread.used_vsr ? regset->n : 0;
}
static int vsr_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
u64 buf[32];
int ret, i;
flush_vsx_to_thread(target);
for (i = 0; i < 32 ; i++)
buf[i] = target->thread.fp_state.fpr[i][TS_VSRLOWOFFSET];
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
buf, 0, 32 * sizeof(double));
return ret;
}
static int vsr_set(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
u64 buf[32];
int ret,i;
flush_vsx_to_thread(target);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
buf, 0, 32 * sizeof(double));
for (i = 0; i < 32 ; i++)
target->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i];
return ret;
}
#endif /* CONFIG_VSX */
#ifdef CONFIG_SPE
/*
* For get_evrregs/set_evrregs functions 'data' has the following layout:
*
* struct {
* u32 evr[32];
* u64 acc;
* u32 spefscr;
* }
*/
static int evr_active(struct task_struct *target,
const struct user_regset *regset)
{
flush_spe_to_thread(target);
return target->thread.used_spe ? regset->n : 0;
}
static int evr_get(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
int ret;
flush_spe_to_thread(target);
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.evr,
0, sizeof(target->thread.evr));
BUILD_BUG_ON(offsetof(struct thread_struct, acc) + sizeof(u64) !=
offsetof(struct thread_struct, spefscr));
if (!ret)
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.acc,
sizeof(target->thread.evr), -1);
return ret;
}
static int evr_set(struct task_struct *target, const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
int ret;
flush_spe_to_thread(target);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.evr,
0, sizeof(target->thread.evr));
BUILD_BUG_ON(offsetof(struct thread_struct, acc) + sizeof(u64) !=
offsetof(struct thread_struct, spefscr));
if (!ret)
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.acc,
sizeof(target->thread.evr), -1);
return ret;
}
#endif /* CONFIG_SPE */
/*
* These are our native regset flavors.
*/
enum powerpc_regset {
REGSET_GPR,
REGSET_FPR,
#ifdef CONFIG_ALTIVEC
REGSET_VMX,
#endif
#ifdef CONFIG_VSX
REGSET_VSX,
#endif
#ifdef CONFIG_SPE
REGSET_SPE,
#endif
};
static const struct user_regset native_regsets[] = {
[REGSET_GPR] = {
.core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
.size = sizeof(long), .align = sizeof(long),
.get = gpr_get, .set = gpr_set
},
[REGSET_FPR] = {
.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
.size = sizeof(double), .align = sizeof(double),
.get = fpr_get, .set = fpr_set
},
#ifdef CONFIG_ALTIVEC
[REGSET_VMX] = {
.core_note_type = NT_PPC_VMX, .n = 34,
.size = sizeof(vector128), .align = sizeof(vector128),
.active = vr_active, .get = vr_get, .set = vr_set
},
#endif
#ifdef CONFIG_VSX
[REGSET_VSX] = {
.core_note_type = NT_PPC_VSX, .n = 32,
.size = sizeof(double), .align = sizeof(double),
.active = vsr_active, .get = vsr_get, .set = vsr_set
},
#endif
#ifdef CONFIG_SPE
[REGSET_SPE] = {
.core_note_type = NT_PPC_SPE, .n = 35,
.size = sizeof(u32), .align = sizeof(u32),
.active = evr_active, .get = evr_get, .set = evr_set
},
#endif
};
static const struct user_regset_view user_ppc_native_view = {
.name = UTS_MACHINE, .e_machine = ELF_ARCH, .ei_osabi = ELF_OSABI,
.regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
};
#ifdef CONFIG_PPC64
#include <linux/compat.h>
static int gpr32_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
const unsigned long *regs = &target->thread.regs->gpr[0];
compat_ulong_t *k = kbuf;
compat_ulong_t __user *u = ubuf;
compat_ulong_t reg;
int i;
if (target->thread.regs == NULL)
return -EIO;
if (!FULL_REGS(target->thread.regs)) {
/* We have a partial register set. Fill 14-31 with bogus values */
for (i = 14; i < 32; i++)
target->thread.regs->gpr[i] = NV_REG_POISON;
}
pos /= sizeof(reg);
count /= sizeof(reg);
if (kbuf)
for (; count > 0 && pos < PT_MSR; --count)
*k++ = regs[pos++];
else
for (; count > 0 && pos < PT_MSR; --count)
if (__put_user((compat_ulong_t) regs[pos++], u++))
return -EFAULT;
if (count > 0 && pos == PT_MSR) {
reg = get_user_msr(target);
if (kbuf)
*k++ = reg;
else if (__put_user(reg, u++))
return -EFAULT;
++pos;
--count;
}
if (kbuf)
for (; count > 0 && pos < PT_REGS_COUNT; --count)
*k++ = regs[pos++];
else
for (; count > 0 && pos < PT_REGS_COUNT; --count)
if (__put_user((compat_ulong_t) regs[pos++], u++))
return -EFAULT;
kbuf = k;
ubuf = u;
pos *= sizeof(reg);
count *= sizeof(reg);
return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
PT_REGS_COUNT * sizeof(reg), -1);
}
static int gpr32_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
unsigned long *regs = &target->thread.regs->gpr[0];
const compat_ulong_t *k = kbuf;
const compat_ulong_t __user *u = ubuf;
compat_ulong_t reg;
if (target->thread.regs == NULL)
return -EIO;
CHECK_FULL_REGS(target->thread.regs);
pos /= sizeof(reg);
count /= sizeof(reg);
if (kbuf)
for (; count > 0 && pos < PT_MSR; --count)
regs[pos++] = *k++;
else
for (; count > 0 && pos < PT_MSR; --count) {
if (__get_user(reg, u++))
return -EFAULT;
regs[pos++] = reg;
}
if (count > 0 && pos == PT_MSR) {
if (kbuf)
reg = *k++;
else if (__get_user(reg, u++))
return -EFAULT;
set_user_msr(target, reg);
++pos;
--count;
}
if (kbuf) {
for (; count > 0 && pos <= PT_MAX_PUT_REG; --count)
regs[pos++] = *k++;
for (; count > 0 && pos < PT_TRAP; --count, ++pos)
++k;
} else {
for (; count > 0 && pos <= PT_MAX_PUT_REG; --count) {
if (__get_user(reg, u++))
return -EFAULT;
regs[pos++] = reg;
}
for (; count > 0 && pos < PT_TRAP; --count, ++pos)
if (__get_user(reg, u++))
return -EFAULT;
}
if (count > 0 && pos == PT_TRAP) {
if (kbuf)
reg = *k++;
else if (__get_user(reg, u++))
return -EFAULT;
set_user_trap(target, reg);
++pos;
--count;
}
kbuf = k;
ubuf = u;
pos *= sizeof(reg);
count *= sizeof(reg);
return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
(PT_TRAP + 1) * sizeof(reg), -1);
}
/*
* These are the regset flavors matching the CONFIG_PPC32 native set.
*/
static const struct user_regset compat_regsets[] = {
[REGSET_GPR] = {
.core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
.size = sizeof(compat_long_t), .align = sizeof(compat_long_t),
.get = gpr32_get, .set = gpr32_set
},
[REGSET_FPR] = {
.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
.size = sizeof(double), .align = sizeof(double),
.get = fpr_get, .set = fpr_set
},
#ifdef CONFIG_ALTIVEC
[REGSET_VMX] = {
.core_note_type = NT_PPC_VMX, .n = 34,
.size = sizeof(vector128), .align = sizeof(vector128),
.active = vr_active, .get = vr_get, .set = vr_set
},
#endif
#ifdef CONFIG_SPE
[REGSET_SPE] = {
.core_note_type = NT_PPC_SPE, .n = 35,
.size = sizeof(u32), .align = sizeof(u32),
.active = evr_active, .get = evr_get, .set = evr_set
},
#endif
};
static const struct user_regset_view user_ppc_compat_view = {
.name = "ppc", .e_machine = EM_PPC, .ei_osabi = ELF_OSABI,
.regsets = compat_regsets, .n = ARRAY_SIZE(compat_regsets)
};
#endif /* CONFIG_PPC64 */
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
#ifdef CONFIG_PPC64
if (test_tsk_thread_flag(task, TIF_32BIT))
return &user_ppc_compat_view;
#endif
return &user_ppc_native_view;
}
void user_enable_single_step(struct task_struct *task)
{
struct pt_regs *regs = task->thread.regs;
if (regs != NULL) {
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
task->thread.debug.dbcr0 &= ~DBCR0_BT;
task->thread.debug.dbcr0 |= DBCR0_IDM | DBCR0_IC;
regs->msr |= MSR_DE;
#else
regs->msr &= ~MSR_BE;
regs->msr |= MSR_SE;
#endif
}
set_tsk_thread_flag(task, TIF_SINGLESTEP);
}
void user_enable_block_step(struct task_struct *task)
{
struct pt_regs *regs = task->thread.regs;
if (regs != NULL) {
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
task->thread.debug.dbcr0 &= ~DBCR0_IC;
task->thread.debug.dbcr0 = DBCR0_IDM | DBCR0_BT;
regs->msr |= MSR_DE;
#else
regs->msr &= ~MSR_SE;
regs->msr |= MSR_BE;
#endif
}
set_tsk_thread_flag(task, TIF_SINGLESTEP);
}
void user_disable_single_step(struct task_struct *task)
{
struct pt_regs *regs = task->thread.regs;
if (regs != NULL) {
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
/*
* The logic to disable single stepping should be as
* simple as turning off the Instruction Complete flag.
* And, after doing so, if all debug flags are off, turn
* off DBCR0(IDM) and MSR(DE) .... Torez
*/
task->thread.debug.dbcr0 &= ~(DBCR0_IC|DBCR0_BT);
/*
* Test to see if any of the DBCR_ACTIVE_EVENTS bits are set.
*/
if (!DBCR_ACTIVE_EVENTS(task->thread.debug.dbcr0,
task->thread.debug.dbcr1)) {
/*
* All debug events were off.....
*/
task->thread.debug.dbcr0 &= ~DBCR0_IDM;
regs->msr &= ~MSR_DE;
}
#else
regs->msr &= ~(MSR_SE | MSR_BE);
#endif
}
clear_tsk_thread_flag(task, TIF_SINGLESTEP);
}
#ifdef CONFIG_HAVE_HW_BREAKPOINT
void ptrace_triggered(struct perf_event *bp,
struct perf_sample_data *data, struct pt_regs *regs)
{
struct perf_event_attr attr;
/*
* Disable the breakpoint request here since ptrace has defined a
* one-shot behaviour for breakpoint exceptions in PPC64.
* The SIGTRAP signal is generated automatically for us in do_dabr().
* We don't have to do anything about that here
*/
attr = bp->attr;
attr.disabled = true;
modify_user_hw_breakpoint(bp, &attr);
}
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
static int ptrace_set_debugreg(struct task_struct *task, unsigned long addr,
unsigned long data)
{
#ifdef CONFIG_HAVE_HW_BREAKPOINT
int ret;
struct thread_struct *thread = &(task->thread);
struct perf_event *bp;
struct perf_event_attr attr;
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
#ifndef CONFIG_PPC_ADV_DEBUG_REGS
struct arch_hw_breakpoint hw_brk;
#endif
/* For ppc64 we support one DABR and no IABR's at the moment (ppc64).
* For embedded processors we support one DAC and no IAC's at the
* moment.
*/
if (addr > 0)
return -EINVAL;
/* The bottom 3 bits in dabr are flags */
if ((data & ~0x7UL) >= TASK_SIZE)
return -EIO;
#ifndef CONFIG_PPC_ADV_DEBUG_REGS
/* For processors using DABR (i.e. 970), the bottom 3 bits are flags.
* It was assumed, on previous implementations, that 3 bits were
* passed together with the data address, fitting the design of the
* DABR register, as follows:
*
* bit 0: Read flag
* bit 1: Write flag
* bit 2: Breakpoint translation
*
* Thus, we use them here as so.
*/
/* Ensure breakpoint translation bit is set */
if (data && !(data & HW_BRK_TYPE_TRANSLATE))
return -EIO;
hw_brk.address = data & (~HW_BRK_TYPE_DABR);
hw_brk.type = (data & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;
hw_brk.len = 8;
#ifdef CONFIG_HAVE_HW_BREAKPOINT
bp = thread->ptrace_bps[0];
if ((!data) || !(hw_brk.type & HW_BRK_TYPE_RDWR)) {
if (bp) {
unregister_hw_breakpoint(bp);
thread->ptrace_bps[0] = NULL;
}
return 0;
}
if (bp) {
attr = bp->attr;
attr.bp_addr = hw_brk.address;
arch_bp_generic_fields(hw_brk.type, &attr.bp_type);
/* Enable breakpoint */
attr.disabled = false;
ret = modify_user_hw_breakpoint(bp, &attr);
if (ret) {
return ret;
}
thread->ptrace_bps[0] = bp;
thread->hw_brk = hw_brk;
return 0;
}
/* Create a new breakpoint request if one doesn't exist already */
hw_breakpoint_init(&attr);
attr.bp_addr = hw_brk.address;
arch_bp_generic_fields(hw_brk.type,
&attr.bp_type);
thread->ptrace_bps[0] = bp = register_user_hw_breakpoint(&attr,
ptrace_triggered, NULL, task);
if (IS_ERR(bp)) {
thread->ptrace_bps[0] = NULL;
return PTR_ERR(bp);
}
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
task->thread.hw_brk = hw_brk;
#else /* CONFIG_PPC_ADV_DEBUG_REGS */
/* As described above, it was assumed 3 bits were passed with the data
* address, but we will assume only the mode bits will be passed
* as to not cause alignment restrictions for DAC-based processors.
*/
/* DAC's hold the whole address without any mode flags */
task->thread.debug.dac1 = data & ~0x3UL;
if (task->thread.debug.dac1 == 0) {
dbcr_dac(task) &= ~(DBCR_DAC1R | DBCR_DAC1W);
if (!DBCR_ACTIVE_EVENTS(task->thread.debug.dbcr0,
task->thread.debug.dbcr1)) {
task->thread.regs->msr &= ~MSR_DE;
task->thread.debug.dbcr0 &= ~DBCR0_IDM;
}
return 0;
}
/* Read or Write bits must be set */
if (!(data & 0x3UL))
return -EINVAL;
/* Set the Internal Debugging flag (IDM bit 1) for the DBCR0
register */
task->thread.debug.dbcr0 |= DBCR0_IDM;
/* Check for write and read flags and set DBCR0
accordingly */
dbcr_dac(task) &= ~(DBCR_DAC1R|DBCR_DAC1W);
if (data & 0x1UL)
dbcr_dac(task) |= DBCR_DAC1R;
if (data & 0x2UL)
dbcr_dac(task) |= DBCR_DAC1W;
task->thread.regs->msr |= MSR_DE;
#endif /* CONFIG_PPC_ADV_DEBUG_REGS */
return 0;
}
/*
* Called by kernel/ptrace.c when detaching..
*
* Make sure single step bits etc are not set.
*/
void ptrace_disable(struct task_struct *child)
{
/* make sure the single step bit is not set. */
user_disable_single_step(child);
}
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
static long set_instruction_bp(struct task_struct *child,
struct ppc_hw_breakpoint *bp_info)
{
int slot;
int slot1_in_use = ((child->thread.debug.dbcr0 & DBCR0_IAC1) != 0);
int slot2_in_use = ((child->thread.debug.dbcr0 & DBCR0_IAC2) != 0);
int slot3_in_use = ((child->thread.debug.dbcr0 & DBCR0_IAC3) != 0);
int slot4_in_use = ((child->thread.debug.dbcr0 & DBCR0_IAC4) != 0);
if (dbcr_iac_range(child) & DBCR_IAC12MODE)
slot2_in_use = 1;
if (dbcr_iac_range(child) & DBCR_IAC34MODE)
slot4_in_use = 1;
if (bp_info->addr >= TASK_SIZE)
return -EIO;
if (bp_info->addr_mode != PPC_BREAKPOINT_MODE_EXACT) {
/* Make sure range is valid. */
if (bp_info->addr2 >= TASK_SIZE)
return -EIO;
/* We need a pair of IAC regsisters */
if ((!slot1_in_use) && (!slot2_in_use)) {
slot = 1;
child->thread.debug.iac1 = bp_info->addr;
child->thread.debug.iac2 = bp_info->addr2;
child->thread.debug.dbcr0 |= DBCR0_IAC1;
if (bp_info->addr_mode ==
PPC_BREAKPOINT_MODE_RANGE_EXCLUSIVE)
dbcr_iac_range(child) |= DBCR_IAC12X;
else
dbcr_iac_range(child) |= DBCR_IAC12I;
#if CONFIG_PPC_ADV_DEBUG_IACS > 2
} else if ((!slot3_in_use) && (!slot4_in_use)) {
slot = 3;
child->thread.debug.iac3 = bp_info->addr;
child->thread.debug.iac4 = bp_info->addr2;
child->thread.debug.dbcr0 |= DBCR0_IAC3;
if (bp_info->addr_mode ==
PPC_BREAKPOINT_MODE_RANGE_EXCLUSIVE)
dbcr_iac_range(child) |= DBCR_IAC34X;
else
dbcr_iac_range(child) |= DBCR_IAC34I;
#endif
} else
return -ENOSPC;
} else {
/* We only need one. If possible leave a pair free in
* case a range is needed later
*/
if (!slot1_in_use) {
/*
* Don't use iac1 if iac1-iac2 are free and either
* iac3 or iac4 (but not both) are free
*/
if (slot2_in_use || (slot3_in_use == slot4_in_use)) {
slot = 1;
child->thread.debug.iac1 = bp_info->addr;
child->thread.debug.dbcr0 |= DBCR0_IAC1;
goto out;
}
}
if (!slot2_in_use) {
slot = 2;
child->thread.debug.iac2 = bp_info->addr;
child->thread.debug.dbcr0 |= DBCR0_IAC2;
#if CONFIG_PPC_ADV_DEBUG_IACS > 2
} else if (!slot3_in_use) {
slot = 3;
child->thread.debug.iac3 = bp_info->addr;
child->thread.debug.dbcr0 |= DBCR0_IAC3;
} else if (!slot4_in_use) {
slot = 4;
child->thread.debug.iac4 = bp_info->addr;
child->thread.debug.dbcr0 |= DBCR0_IAC4;
#endif
} else
return -ENOSPC;
}
out:
child->thread.debug.dbcr0 |= DBCR0_IDM;
child->thread.regs->msr |= MSR_DE;
return slot;
}
static int del_instruction_bp(struct task_struct *child, int slot)
{
switch (slot) {
case 1:
if ((child->thread.debug.dbcr0 & DBCR0_IAC1) == 0)
return -ENOENT;
if (dbcr_iac_range(child) & DBCR_IAC12MODE) {
/* address range - clear slots 1 & 2 */
child->thread.debug.iac2 = 0;
dbcr_iac_range(child) &= ~DBCR_IAC12MODE;
}
child->thread.debug.iac1 = 0;
child->thread.debug.dbcr0 &= ~DBCR0_IAC1;
break;
case 2:
if ((child->thread.debug.dbcr0 & DBCR0_IAC2) == 0)
return -ENOENT;
if (dbcr_iac_range(child) & DBCR_IAC12MODE)
/* used in a range */
return -EINVAL;
child->thread.debug.iac2 = 0;
child->thread.debug.dbcr0 &= ~DBCR0_IAC2;
break;
#if CONFIG_PPC_ADV_DEBUG_IACS > 2
case 3:
if ((child->thread.debug.dbcr0 & DBCR0_IAC3) == 0)
return -ENOENT;
if (dbcr_iac_range(child) & DBCR_IAC34MODE) {
/* address range - clear slots 3 & 4 */
child->thread.debug.iac4 = 0;
dbcr_iac_range(child) &= ~DBCR_IAC34MODE;
}
child->thread.debug.iac3 = 0;
child->thread.debug.dbcr0 &= ~DBCR0_IAC3;
break;
case 4:
if ((child->thread.debug.dbcr0 & DBCR0_IAC4) == 0)
return -ENOENT;
if (dbcr_iac_range(child) & DBCR_IAC34MODE)
/* Used in a range */
return -EINVAL;
child->thread.debug.iac4 = 0;
child->thread.debug.dbcr0 &= ~DBCR0_IAC4;
break;
#endif
default:
return -EINVAL;
}
return 0;
}
static int set_dac(struct task_struct *child, struct ppc_hw_breakpoint *bp_info)
{
int byte_enable =
(bp_info->condition_mode >> PPC_BREAKPOINT_CONDITION_BE_SHIFT)
& 0xf;
int condition_mode =
bp_info->condition_mode & PPC_BREAKPOINT_CONDITION_MODE;
int slot;
if (byte_enable && (condition_mode == 0))
return -EINVAL;
if (bp_info->addr >= TASK_SIZE)
return -EIO;
if ((dbcr_dac(child) & (DBCR_DAC1R | DBCR_DAC1W)) == 0) {
slot = 1;
if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_READ)
dbcr_dac(child) |= DBCR_DAC1R;
if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE)
dbcr_dac(child) |= DBCR_DAC1W;
child->thread.debug.dac1 = (unsigned long)bp_info->addr;
#if CONFIG_PPC_ADV_DEBUG_DVCS > 0
if (byte_enable) {
child->thread.debug.dvc1 =
(unsigned long)bp_info->condition_value;
child->thread.debug.dbcr2 |=
((byte_enable << DBCR2_DVC1BE_SHIFT) |
(condition_mode << DBCR2_DVC1M_SHIFT));
}
#endif
#ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE
} else if (child->thread.debug.dbcr2 & DBCR2_DAC12MODE) {
/* Both dac1 and dac2 are part of a range */
return -ENOSPC;
#endif
} else if ((dbcr_dac(child) & (DBCR_DAC2R | DBCR_DAC2W)) == 0) {
slot = 2;
if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_READ)
dbcr_dac(child) |= DBCR_DAC2R;
if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE)
dbcr_dac(child) |= DBCR_DAC2W;
child->thread.debug.dac2 = (unsigned long)bp_info->addr;
#if CONFIG_PPC_ADV_DEBUG_DVCS > 0
if (byte_enable) {
child->thread.debug.dvc2 =
(unsigned long)bp_info->condition_value;
child->thread.debug.dbcr2 |=
((byte_enable << DBCR2_DVC2BE_SHIFT) |
(condition_mode << DBCR2_DVC2M_SHIFT));
}
#endif
} else
return -ENOSPC;
child->thread.debug.dbcr0 |= DBCR0_IDM;
child->thread.regs->msr |= MSR_DE;
return slot + 4;
}
static int del_dac(struct task_struct *child, int slot)
{
if (slot == 1) {
if ((dbcr_dac(child) & (DBCR_DAC1R | DBCR_DAC1W)) == 0)
return -ENOENT;
child->thread.debug.dac1 = 0;
dbcr_dac(child) &= ~(DBCR_DAC1R | DBCR_DAC1W);
#ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE
if (child->thread.debug.dbcr2 & DBCR2_DAC12MODE) {
child->thread.debug.dac2 = 0;
child->thread.debug.dbcr2 &= ~DBCR2_DAC12MODE;
}
child->thread.debug.dbcr2 &= ~(DBCR2_DVC1M | DBCR2_DVC1BE);
#endif
#if CONFIG_PPC_ADV_DEBUG_DVCS > 0
child->thread.debug.dvc1 = 0;
#endif
} else if (slot == 2) {
if ((dbcr_dac(child) & (DBCR_DAC2R | DBCR_DAC2W)) == 0)
return -ENOENT;
#ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE
if (child->thread.debug.dbcr2 & DBCR2_DAC12MODE)
/* Part of a range */
return -EINVAL;
child->thread.debug.dbcr2 &= ~(DBCR2_DVC2M | DBCR2_DVC2BE);
#endif
#if CONFIG_PPC_ADV_DEBUG_DVCS > 0
child->thread.debug.dvc2 = 0;
#endif
child->thread.debug.dac2 = 0;
dbcr_dac(child) &= ~(DBCR_DAC2R | DBCR_DAC2W);
} else
return -EINVAL;
return 0;
}
#endif /* CONFIG_PPC_ADV_DEBUG_REGS */
#ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE
static int set_dac_range(struct task_struct *child,
struct ppc_hw_breakpoint *bp_info)
{
int mode = bp_info->addr_mode & PPC_BREAKPOINT_MODE_MASK;
/* We don't allow range watchpoints to be used with DVC */
if (bp_info->condition_mode)
return -EINVAL;
/*
* Best effort to verify the address range. The user/supervisor bits
* prevent trapping in kernel space, but let's fail on an obvious bad
* range. The simple test on the mask is not fool-proof, and any
* exclusive range will spill over into kernel space.
*/
if (bp_info->addr >= TASK_SIZE)
return -EIO;
if (mode == PPC_BREAKPOINT_MODE_MASK) {
/*
* dac2 is a bitmask. Don't allow a mask that makes a
* kernel space address from a valid dac1 value
*/
if (~((unsigned long)bp_info->addr2) >= TASK_SIZE)
return -EIO;
} else {
/*
* For range breakpoints, addr2 must also be a valid address
*/
if (bp_info->addr2 >= TASK_SIZE)
return -EIO;
}
if (child->thread.debug.dbcr0 &
(DBCR0_DAC1R | DBCR0_DAC1W | DBCR0_DAC2R | DBCR0_DAC2W))
return -ENOSPC;
if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_READ)
child->thread.debug.dbcr0 |= (DBCR0_DAC1R | DBCR0_IDM);
if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE)
child->thread.debug.dbcr0 |= (DBCR0_DAC1W | DBCR0_IDM);
child->thread.debug.dac1 = bp_info->addr;
child->thread.debug.dac2 = bp_info->addr2;
if (mode == PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE)
child->thread.debug.dbcr2 |= DBCR2_DAC12M;
else if (mode == PPC_BREAKPOINT_MODE_RANGE_EXCLUSIVE)
child->thread.debug.dbcr2 |= DBCR2_DAC12MX;
else /* PPC_BREAKPOINT_MODE_MASK */
child->thread.debug.dbcr2 |= DBCR2_DAC12MM;
child->thread.regs->msr |= MSR_DE;
return 5;
}
#endif /* CONFIG_PPC_ADV_DEBUG_DAC_RANGE */
static long ppc_set_hwdebug(struct task_struct *child,
struct ppc_hw_breakpoint *bp_info)
{
#ifdef CONFIG_HAVE_HW_BREAKPOINT
int len = 0;
struct thread_struct *thread = &(child->thread);
struct perf_event *bp;
struct perf_event_attr attr;
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
#ifndef CONFIG_PPC_ADV_DEBUG_REGS
struct arch_hw_breakpoint brk;
#endif
if (bp_info->version != 1)
return -ENOTSUPP;
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
/*
* Check for invalid flags and combinations
*/
if ((bp_info->trigger_type == 0) ||
(bp_info->trigger_type & ~(PPC_BREAKPOINT_TRIGGER_EXECUTE |
PPC_BREAKPOINT_TRIGGER_RW)) ||
(bp_info->addr_mode & ~PPC_BREAKPOINT_MODE_MASK) ||
(bp_info->condition_mode &
~(PPC_BREAKPOINT_CONDITION_MODE |
PPC_BREAKPOINT_CONDITION_BE_ALL)))
return -EINVAL;
#if CONFIG_PPC_ADV_DEBUG_DVCS == 0
if (bp_info->condition_mode != PPC_BREAKPOINT_CONDITION_NONE)
return -EINVAL;
#endif
if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_EXECUTE) {
if ((bp_info->trigger_type != PPC_BREAKPOINT_TRIGGER_EXECUTE) ||
(bp_info->condition_mode != PPC_BREAKPOINT_CONDITION_NONE))
return -EINVAL;
return set_instruction_bp(child, bp_info);
}
if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_EXACT)
return set_dac(child, bp_info);
#ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE
return set_dac_range(child, bp_info);
#else
return -EINVAL;
#endif
#else /* !CONFIG_PPC_ADV_DEBUG_DVCS */
/*
* We only support one data breakpoint
*/
if ((bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_RW) == 0 ||
(bp_info->trigger_type & ~PPC_BREAKPOINT_TRIGGER_RW) != 0 ||
bp_info->condition_mode != PPC_BREAKPOINT_CONDITION_NONE)
return -EINVAL;
if ((unsigned long)bp_info->addr >= TASK_SIZE)
return -EIO;
brk.address = bp_info->addr & ~7UL;
brk.type = HW_BRK_TYPE_TRANSLATE;
brk.len = 8;
if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_READ)
brk.type |= HW_BRK_TYPE_READ;
if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE)
brk.type |= HW_BRK_TYPE_WRITE;
#ifdef CONFIG_HAVE_HW_BREAKPOINT
/*
* Check if the request is for 'range' breakpoints. We can
* support it if range < 8 bytes.
*/
if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE)
len = bp_info->addr2 - bp_info->addr;
else if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_EXACT)
len = 1;
else
return -EINVAL;
bp = thread->ptrace_bps[0];
if (bp)
return -ENOSPC;
/* Create a new breakpoint request if one doesn't exist already */
hw_breakpoint_init(&attr);
attr.bp_addr = (unsigned long)bp_info->addr & ~HW_BREAKPOINT_ALIGN;
attr.bp_len = len;
arch_bp_generic_fields(brk.type, &attr.bp_type);
thread->ptrace_bps[0] = bp = register_user_hw_breakpoint(&attr,
ptrace_triggered, NULL, child);
if (IS_ERR(bp)) {
thread->ptrace_bps[0] = NULL;
return PTR_ERR(bp);
}
return 1;
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
if (bp_info->addr_mode != PPC_BREAKPOINT_MODE_EXACT)
return -EINVAL;
if (child->thread.hw_brk.address)
return -ENOSPC;
child->thread.hw_brk = brk;
return 1;
#endif /* !CONFIG_PPC_ADV_DEBUG_DVCS */
}
static long ppc_del_hwdebug(struct task_struct *child, long data)
{
#ifdef CONFIG_HAVE_HW_BREAKPOINT
int ret = 0;
struct thread_struct *thread = &(child->thread);
struct perf_event *bp;
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
int rc;
if (data <= 4)
rc = del_instruction_bp(child, (int)data);
else
rc = del_dac(child, (int)data - 4);
if (!rc) {
if (!DBCR_ACTIVE_EVENTS(child->thread.debug.dbcr0,
child->thread.debug.dbcr1)) {
child->thread.debug.dbcr0 &= ~DBCR0_IDM;
child->thread.regs->msr &= ~MSR_DE;
}
}
return rc;
#else
if (data != 1)
return -EINVAL;
#ifdef CONFIG_HAVE_HW_BREAKPOINT
bp = thread->ptrace_bps[0];
if (bp) {
unregister_hw_breakpoint(bp);
thread->ptrace_bps[0] = NULL;
} else
ret = -ENOENT;
return ret;
#else /* CONFIG_HAVE_HW_BREAKPOINT */
if (child->thread.hw_brk.address == 0)
return -ENOENT;
child->thread.hw_brk.address = 0;
child->thread.hw_brk.type = 0;
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
return 0;
#endif
}
long arch_ptrace(struct task_struct *child, long request,
unsigned long addr, unsigned long data)
{
int ret = -EPERM;
void __user *datavp = (void __user *) data;
unsigned long __user *datalp = datavp;
switch (request) {
/* read the word at location addr in the USER area. */
case PTRACE_PEEKUSR: {
unsigned long index, tmp;
ret = -EIO;
/* convert to index and check */
#ifdef CONFIG_PPC32
index = addr >> 2;
if ((addr & 3) || (index > PT_FPSCR)
|| (child->thread.regs == NULL))
#else
index = addr >> 3;
if ((addr & 7) || (index > PT_FPSCR))
#endif
break;
CHECK_FULL_REGS(child->thread.regs);
if (index < PT_FPR0) {
ret = ptrace_get_reg(child, (int) index, &tmp);
if (ret)
break;
} else {
unsigned int fpidx = index - PT_FPR0;
flush_fp_to_thread(child);
if (fpidx < (PT_FPSCR - PT_FPR0))
memcpy(&tmp, &child->thread.TS_FPR(fpidx),
sizeof(long));
else
tmp = child->thread.fp_state.fpscr;
}
ret = put_user(tmp, datalp);
break;
}
/* write the word at location addr in the USER area */
case PTRACE_POKEUSR: {
unsigned long index;
ret = -EIO;
/* convert to index and check */
#ifdef CONFIG_PPC32
index = addr >> 2;
if ((addr & 3) || (index > PT_FPSCR)
|| (child->thread.regs == NULL))
#else
index = addr >> 3;
if ((addr & 7) || (index > PT_FPSCR))
#endif
break;
CHECK_FULL_REGS(child->thread.regs);
if (index < PT_FPR0) {
ret = ptrace_put_reg(child, index, data);
} else {
unsigned int fpidx = index - PT_FPR0;
flush_fp_to_thread(child);
if (fpidx < (PT_FPSCR - PT_FPR0))
memcpy(&child->thread.TS_FPR(fpidx), &data,
sizeof(long));
else
child->thread.fp_state.fpscr = data;
ret = 0;
}
break;
}
case PPC_PTRACE_GETHWDBGINFO: {
struct ppc_debug_info dbginfo;
dbginfo.version = 1;
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
dbginfo.num_instruction_bps = CONFIG_PPC_ADV_DEBUG_IACS;
dbginfo.num_data_bps = CONFIG_PPC_ADV_DEBUG_DACS;
dbginfo.num_condition_regs = CONFIG_PPC_ADV_DEBUG_DVCS;
dbginfo.data_bp_alignment = 4;
dbginfo.sizeof_condition = 4;
dbginfo.features = PPC_DEBUG_FEATURE_INSN_BP_RANGE |
PPC_DEBUG_FEATURE_INSN_BP_MASK;
#ifdef CONFIG_PPC_ADV_DEBUG_DAC_RANGE
dbginfo.features |=
PPC_DEBUG_FEATURE_DATA_BP_RANGE |
PPC_DEBUG_FEATURE_DATA_BP_MASK;
#endif
#else /* !CONFIG_PPC_ADV_DEBUG_REGS */
dbginfo.num_instruction_bps = 0;
dbginfo.num_data_bps = 1;
dbginfo.num_condition_regs = 0;
#ifdef CONFIG_PPC64
dbginfo.data_bp_alignment = 8;
#else
dbginfo.data_bp_alignment = 4;
#endif
dbginfo.sizeof_condition = 0;
#ifdef CONFIG_HAVE_HW_BREAKPOINT
dbginfo.features = PPC_DEBUG_FEATURE_DATA_BP_RANGE;
if (cpu_has_feature(CPU_FTR_DAWR))
dbginfo.features |= PPC_DEBUG_FEATURE_DATA_BP_DAWR;
#else
dbginfo.features = 0;
#endif /* CONFIG_HAVE_HW_BREAKPOINT */
#endif /* CONFIG_PPC_ADV_DEBUG_REGS */
if (!access_ok(VERIFY_WRITE, datavp,
sizeof(struct ppc_debug_info)))
return -EFAULT;
ret = __copy_to_user(datavp, &dbginfo,
sizeof(struct ppc_debug_info)) ?
-EFAULT : 0;
break;
}
case PPC_PTRACE_SETHWDEBUG: {
struct ppc_hw_breakpoint bp_info;
if (!access_ok(VERIFY_READ, datavp,
sizeof(struct ppc_hw_breakpoint)))
return -EFAULT;
ret = __copy_from_user(&bp_info, datavp,
sizeof(struct ppc_hw_breakpoint)) ?
-EFAULT : 0;
if (!ret)
ret = ppc_set_hwdebug(child, &bp_info);
break;
}
case PPC_PTRACE_DELHWDEBUG: {
ret = ppc_del_hwdebug(child, data);
break;
}
case PTRACE_GET_DEBUGREG: {
#ifndef CONFIG_PPC_ADV_DEBUG_REGS
unsigned long dabr_fake;
#endif
ret = -EINVAL;
/* We only support one DABR and no IABRS at the moment */
if (addr > 0)
break;
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
ret = put_user(child->thread.debug.dac1, datalp);
#else
dabr_fake = ((child->thread.hw_brk.address & (~HW_BRK_TYPE_DABR)) |
(child->thread.hw_brk.type & HW_BRK_TYPE_DABR));
ret = put_user(dabr_fake, datalp);
#endif
break;
}
case PTRACE_SET_DEBUGREG:
ret = ptrace_set_debugreg(child, addr, data);
break;
#ifdef CONFIG_PPC64
case PTRACE_GETREGS64:
#endif
case PTRACE_GETREGS: /* Get all pt_regs from the child. */
return copy_regset_to_user(child, &user_ppc_native_view,
REGSET_GPR,
0, sizeof(struct pt_regs),
datavp);
#ifdef CONFIG_PPC64
case PTRACE_SETREGS64:
#endif
case PTRACE_SETREGS: /* Set all gp regs in the child. */
return copy_regset_from_user(child, &user_ppc_native_view,
REGSET_GPR,
0, sizeof(struct pt_regs),
datavp);
case PTRACE_GETFPREGS: /* Get the child FPU state (FPR0...31 + FPSCR) */
return copy_regset_to_user(child, &user_ppc_native_view,
REGSET_FPR,
0, sizeof(elf_fpregset_t),
datavp);
case PTRACE_SETFPREGS: /* Set the child FPU state (FPR0...31 + FPSCR) */
return copy_regset_from_user(child, &user_ppc_native_view,
REGSET_FPR,
0, sizeof(elf_fpregset_t),
datavp);
#ifdef CONFIG_ALTIVEC
case PTRACE_GETVRREGS:
return copy_regset_to_user(child, &user_ppc_native_view,
REGSET_VMX,
0, (33 * sizeof(vector128) +
sizeof(u32)),
datavp);
case PTRACE_SETVRREGS:
return copy_regset_from_user(child, &user_ppc_native_view,
REGSET_VMX,
0, (33 * sizeof(vector128) +
sizeof(u32)),
datavp);
#endif
#ifdef CONFIG_VSX
case PTRACE_GETVSRREGS:
return copy_regset_to_user(child, &user_ppc_native_view,
REGSET_VSX,
0, 32 * sizeof(double),
datavp);
case PTRACE_SETVSRREGS:
return copy_regset_from_user(child, &user_ppc_native_view,
REGSET_VSX,
0, 32 * sizeof(double),
datavp);
#endif
#ifdef CONFIG_SPE
case PTRACE_GETEVRREGS:
/* Get the child spe register state. */
return copy_regset_to_user(child, &user_ppc_native_view,
REGSET_SPE, 0, 35 * sizeof(u32),
datavp);
case PTRACE_SETEVRREGS:
/* Set the child spe register state. */
return copy_regset_from_user(child, &user_ppc_native_view,
REGSET_SPE, 0, 35 * sizeof(u32),
datavp);
#endif
default:
ret = ptrace_request(child, request, addr, data);
break;
}
return ret;
}
#ifdef CONFIG_SECCOMP
static int do_seccomp(struct pt_regs *regs)
{
if (!test_thread_flag(TIF_SECCOMP))
return 0;
/*
* The ABI we present to seccomp tracers is that r3 contains
* the syscall return value and orig_gpr3 contains the first
* syscall parameter. This is different to the ptrace ABI where
* both r3 and orig_gpr3 contain the first syscall parameter.
*/
regs->gpr[3] = -ENOSYS;
/*
* We use the __ version here because we have already checked
* TIF_SECCOMP. If this fails, there is nothing left to do, we
* have already loaded -ENOSYS into r3, or seccomp has put
* something else in r3 (via SECCOMP_RET_ERRNO/TRACE).
*/
if (__secure_computing())
return -1;
/*
* The syscall was allowed by seccomp, restore the register
* state to what ptrace and audit expect.
* Note that we use orig_gpr3, which means a seccomp tracer can
* modify the first syscall parameter (in orig_gpr3) and also
* allow the syscall to proceed.
*/
regs->gpr[3] = regs->orig_gpr3;
return 0;
}
#else
static inline int do_seccomp(struct pt_regs *regs) { return 0; }
#endif /* CONFIG_SECCOMP */
/**
* do_syscall_trace_enter() - Do syscall tracing on kernel entry.
* @regs: the pt_regs of the task to trace (current)
*
* Performs various types of tracing on syscall entry. This includes seccomp,
* ptrace, syscall tracepoints and audit.
*
* The pt_regs are potentially visible to userspace via ptrace, so their
* contents is ABI.
*
* One or more of the tracers may modify the contents of pt_regs, in particular
* to modify arguments or even the syscall number itself.
*
* It's also possible that a tracer can choose to reject the system call. In
* that case this function will return an illegal syscall number, and will put
* an appropriate return value in regs->r3.
*
* Return: the (possibly changed) syscall number.
*/
long do_syscall_trace_enter(struct pt_regs *regs)
{
bool abort = false;
user_exit();
if (do_seccomp(regs))
return -1;
if (test_thread_flag(TIF_SYSCALL_TRACE)) {
/*
* The tracer may decide to abort the syscall, if so tracehook
* will return !0. Note that the tracer may also just change
* regs->gpr[0] to an invalid syscall number, that is handled
* below on the exit path.
*/
abort = tracehook_report_syscall_entry(regs) != 0;
}
if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
trace_sys_enter(regs, regs->gpr[0]);
#ifdef CONFIG_PPC64
if (!is_32bit_task())
audit_syscall_entry(regs->gpr[0], regs->gpr[3], regs->gpr[4],
regs->gpr[5], regs->gpr[6]);
else
#endif
audit_syscall_entry(regs->gpr[0],
regs->gpr[3] & 0xffffffff,
regs->gpr[4] & 0xffffffff,
regs->gpr[5] & 0xffffffff,
regs->gpr[6] & 0xffffffff);
if (abort || regs->gpr[0] >= NR_syscalls) {
/*
* If we are aborting explicitly, or if the syscall number is
* now invalid, set the return value to -ENOSYS.
*/
regs->gpr[3] = -ENOSYS;
return -1;
}
/* Return the possibly modified but valid syscall number */
return regs->gpr[0];
}
void do_syscall_trace_leave(struct pt_regs *regs)
{
int step;
audit_syscall_exit(regs);
if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
trace_sys_exit(regs, regs->result);
step = test_thread_flag(TIF_SINGLESTEP);
if (step || test_thread_flag(TIF_SYSCALL_TRACE))
tracehook_report_syscall_exit(regs, step);
user_enter();
}