summaryrefslogtreecommitdiff
path: root/arch/sh/kernel/ptrace_64.c
diff options
context:
space:
mode:
authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/sh/kernel/ptrace_64.c
Initial import
Diffstat (limited to 'arch/sh/kernel/ptrace_64.c')
-rw-r--r--arch/sh/kernel/ptrace_64.c578
1 files changed, 578 insertions, 0 deletions
diff --git a/arch/sh/kernel/ptrace_64.c b/arch/sh/kernel/ptrace_64.c
new file mode 100644
index 000000000..5cea973a6
--- /dev/null
+++ b/arch/sh/kernel/ptrace_64.c
@@ -0,0 +1,578 @@
+/*
+ * arch/sh/kernel/ptrace_64.c
+ *
+ * Copyright (C) 2000, 2001 Paolo Alberelli
+ * Copyright (C) 2003 - 2008 Paul Mundt
+ *
+ * Started from SH3/4 version:
+ * SuperH version: Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka
+ *
+ * Original x86 implementation:
+ * By Ross Biro 1/23/92
+ * edited by Linus Torvalds
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/signal.h>
+#include <linux/syscalls.h>
+#include <linux/audit.h>
+#include <linux/seccomp.h>
+#include <linux/tracehook.h>
+#include <linux/elf.h>
+#include <linux/regset.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/mmu_context.h>
+#include <asm/syscalls.h>
+#include <asm/fpu.h>
+#include <asm/traps.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
+/* This mask defines the bits of the SR which the user is not allowed to
+ change, which are everything except S, Q, M, PR, SZ, FR. */
+#define SR_MASK (0xffff8cfd)
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+/*
+ * This routine will get a word from the user area in the process kernel stack.
+ */
+static inline int get_stack_long(struct task_struct *task, int offset)
+{
+ unsigned char *stack;
+
+ stack = (unsigned char *)(task->thread.uregs);
+ stack += offset;
+ return (*((int *)stack));
+}
+
+static inline unsigned long
+get_fpu_long(struct task_struct *task, unsigned long addr)
+{
+ unsigned long tmp;
+ struct pt_regs *regs;
+ regs = (struct pt_regs*)((unsigned char *)task + THREAD_SIZE) - 1;
+
+ if (!tsk_used_math(task)) {
+ if (addr == offsetof(struct user_fpu_struct, fpscr)) {
+ tmp = FPSCR_INIT;
+ } else {
+ tmp = 0xffffffffUL; /* matches initial value in fpu.c */
+ }
+ return tmp;
+ }
+
+ if (last_task_used_math == task) {
+ enable_fpu();
+ save_fpu(task);
+ disable_fpu();
+ last_task_used_math = 0;
+ regs->sr |= SR_FD;
+ }
+
+ tmp = ((long *)task->thread.xstate)[addr / sizeof(unsigned long)];
+ return tmp;
+}
+
+/*
+ * This routine will put a word into the user area in the process kernel stack.
+ */
+static inline int put_stack_long(struct task_struct *task, int offset,
+ unsigned long data)
+{
+ unsigned char *stack;
+
+ stack = (unsigned char *)(task->thread.uregs);
+ stack += offset;
+ *(unsigned long *) stack = data;
+ return 0;
+}
+
+static inline int
+put_fpu_long(struct task_struct *task, unsigned long addr, unsigned long data)
+{
+ struct pt_regs *regs;
+
+ regs = (struct pt_regs*)((unsigned char *)task + THREAD_SIZE) - 1;
+
+ if (!tsk_used_math(task)) {
+ init_fpu(task);
+ } else if (last_task_used_math == task) {
+ enable_fpu();
+ save_fpu(task);
+ disable_fpu();
+ last_task_used_math = 0;
+ regs->sr |= SR_FD;
+ }
+
+ ((long *)task->thread.xstate)[addr / sizeof(unsigned long)] = data;
+ return 0;
+}
+
+void user_enable_single_step(struct task_struct *child)
+{
+ struct pt_regs *regs = child->thread.uregs;
+
+ regs->sr |= SR_SSTEP; /* auto-resetting upon exception */
+
+ set_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+void user_disable_single_step(struct task_struct *child)
+{
+ struct pt_regs *regs = child->thread.uregs;
+
+ regs->sr &= ~SR_SSTEP;
+
+ clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+static int genregs_get(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ const struct pt_regs *regs = task_pt_regs(target);
+ int ret;
+
+ /* PC, SR, SYSCALL */
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ &regs->pc,
+ 0, 3 * sizeof(unsigned long long));
+
+ /* R1 -> R63 */
+ if (!ret)
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ regs->regs,
+ offsetof(struct pt_regs, regs[0]),
+ 63 * sizeof(unsigned long long));
+ /* TR0 -> TR7 */
+ if (!ret)
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ regs->tregs,
+ offsetof(struct pt_regs, tregs[0]),
+ 8 * sizeof(unsigned long long));
+
+ if (!ret)
+ ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
+ sizeof(struct pt_regs), -1);
+
+ return ret;
+}
+
+static int genregs_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ struct pt_regs *regs = task_pt_regs(target);
+ int ret;
+
+ /* PC, SR, SYSCALL */
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &regs->pc,
+ 0, 3 * sizeof(unsigned long long));
+
+ /* R1 -> R63 */
+ if (!ret && count > 0)
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ regs->regs,
+ offsetof(struct pt_regs, regs[0]),
+ 63 * sizeof(unsigned long long));
+
+ /* TR0 -> TR7 */
+ if (!ret && count > 0)
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ regs->tregs,
+ offsetof(struct pt_regs, tregs[0]),
+ 8 * sizeof(unsigned long long));
+
+ if (!ret)
+ ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+ sizeof(struct pt_regs), -1);
+
+ return ret;
+}
+
+#ifdef CONFIG_SH_FPU
+int fpregs_get(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ int ret;
+
+ ret = init_fpu(target);
+ if (ret)
+ return ret;
+
+ return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ &target->thread.xstate->hardfpu, 0, -1);
+}
+
+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)
+{
+ int ret;
+
+ ret = init_fpu(target);
+ if (ret)
+ return ret;
+
+ set_stopped_child_used_math(target);
+
+ return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.xstate->hardfpu, 0, -1);
+}
+
+static int fpregs_active(struct task_struct *target,
+ const struct user_regset *regset)
+{
+ return tsk_used_math(target) ? regset->n : 0;
+}
+#endif
+
+const struct pt_regs_offset regoffset_table[] = {
+ REG_OFFSET_NAME(pc),
+ REG_OFFSET_NAME(sr),
+ REG_OFFSET_NAME(syscall_nr),
+ REGS_OFFSET_NAME(0),
+ REGS_OFFSET_NAME(1),
+ REGS_OFFSET_NAME(2),
+ REGS_OFFSET_NAME(3),
+ REGS_OFFSET_NAME(4),
+ REGS_OFFSET_NAME(5),
+ REGS_OFFSET_NAME(6),
+ REGS_OFFSET_NAME(7),
+ REGS_OFFSET_NAME(8),
+ REGS_OFFSET_NAME(9),
+ REGS_OFFSET_NAME(10),
+ REGS_OFFSET_NAME(11),
+ REGS_OFFSET_NAME(12),
+ REGS_OFFSET_NAME(13),
+ REGS_OFFSET_NAME(14),
+ REGS_OFFSET_NAME(15),
+ REGS_OFFSET_NAME(16),
+ REGS_OFFSET_NAME(17),
+ REGS_OFFSET_NAME(18),
+ REGS_OFFSET_NAME(19),
+ REGS_OFFSET_NAME(20),
+ REGS_OFFSET_NAME(21),
+ REGS_OFFSET_NAME(22),
+ REGS_OFFSET_NAME(23),
+ REGS_OFFSET_NAME(24),
+ REGS_OFFSET_NAME(25),
+ REGS_OFFSET_NAME(26),
+ REGS_OFFSET_NAME(27),
+ REGS_OFFSET_NAME(28),
+ REGS_OFFSET_NAME(29),
+ REGS_OFFSET_NAME(30),
+ REGS_OFFSET_NAME(31),
+ REGS_OFFSET_NAME(32),
+ REGS_OFFSET_NAME(33),
+ REGS_OFFSET_NAME(34),
+ REGS_OFFSET_NAME(35),
+ REGS_OFFSET_NAME(36),
+ REGS_OFFSET_NAME(37),
+ REGS_OFFSET_NAME(38),
+ REGS_OFFSET_NAME(39),
+ REGS_OFFSET_NAME(40),
+ REGS_OFFSET_NAME(41),
+ REGS_OFFSET_NAME(42),
+ REGS_OFFSET_NAME(43),
+ REGS_OFFSET_NAME(44),
+ REGS_OFFSET_NAME(45),
+ REGS_OFFSET_NAME(46),
+ REGS_OFFSET_NAME(47),
+ REGS_OFFSET_NAME(48),
+ REGS_OFFSET_NAME(49),
+ REGS_OFFSET_NAME(50),
+ REGS_OFFSET_NAME(51),
+ REGS_OFFSET_NAME(52),
+ REGS_OFFSET_NAME(53),
+ REGS_OFFSET_NAME(54),
+ REGS_OFFSET_NAME(55),
+ REGS_OFFSET_NAME(56),
+ REGS_OFFSET_NAME(57),
+ REGS_OFFSET_NAME(58),
+ REGS_OFFSET_NAME(59),
+ REGS_OFFSET_NAME(60),
+ REGS_OFFSET_NAME(61),
+ REGS_OFFSET_NAME(62),
+ REGS_OFFSET_NAME(63),
+ TREGS_OFFSET_NAME(0),
+ TREGS_OFFSET_NAME(1),
+ TREGS_OFFSET_NAME(2),
+ TREGS_OFFSET_NAME(3),
+ TREGS_OFFSET_NAME(4),
+ TREGS_OFFSET_NAME(5),
+ TREGS_OFFSET_NAME(6),
+ TREGS_OFFSET_NAME(7),
+ REG_OFFSET_END,
+};
+
+/*
+ * These are our native regset flavours.
+ */
+enum sh_regset {
+ REGSET_GENERAL,
+#ifdef CONFIG_SH_FPU
+ REGSET_FPU,
+#endif
+};
+
+static const struct user_regset sh_regsets[] = {
+ /*
+ * Format is:
+ * PC, SR, SYSCALL,
+ * R1 --> R63,
+ * TR0 --> TR7,
+ */
+ [REGSET_GENERAL] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = ELF_NGREG,
+ .size = sizeof(long long),
+ .align = sizeof(long long),
+ .get = genregs_get,
+ .set = genregs_set,
+ },
+
+#ifdef CONFIG_SH_FPU
+ [REGSET_FPU] = {
+ .core_note_type = NT_PRFPREG,
+ .n = sizeof(struct user_fpu_struct) /
+ sizeof(long long),
+ .size = sizeof(long long),
+ .align = sizeof(long long),
+ .get = fpregs_get,
+ .set = fpregs_set,
+ .active = fpregs_active,
+ },
+#endif
+};
+
+static const struct user_regset_view user_sh64_native_view = {
+ .name = "sh64",
+ .e_machine = EM_SH,
+ .regsets = sh_regsets,
+ .n = ARRAY_SIZE(sh_regsets),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &user_sh64_native_view;
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ int ret;
+ unsigned long __user *datap = (unsigned long __user *) data;
+
+ switch (request) {
+ /* read the word at location addr in the USER area. */
+ case PTRACE_PEEKUSR: {
+ unsigned long tmp;
+
+ ret = -EIO;
+ if ((addr & 3) || addr < 0)
+ break;
+
+ if (addr < sizeof(struct pt_regs))
+ tmp = get_stack_long(child, addr);
+ else if ((addr >= offsetof(struct user, fpu)) &&
+ (addr < offsetof(struct user, u_fpvalid))) {
+ unsigned long index;
+ ret = init_fpu(child);
+ if (ret)
+ break;
+ index = addr - offsetof(struct user, fpu);
+ tmp = get_fpu_long(child, index);
+ } else if (addr == offsetof(struct user, u_fpvalid)) {
+ tmp = !!tsk_used_math(child);
+ } else {
+ break;
+ }
+ ret = put_user(tmp, datap);
+ break;
+ }
+
+ case PTRACE_POKEUSR:
+ /* write the word at location addr in the USER area. We must
+ disallow any changes to certain SR bits or u_fpvalid, since
+ this could crash the kernel or result in a security
+ loophole. */
+ ret = -EIO;
+ if ((addr & 3) || addr < 0)
+ break;
+
+ if (addr < sizeof(struct pt_regs)) {
+ /* Ignore change of top 32 bits of SR */
+ if (addr == offsetof (struct pt_regs, sr)+4)
+ {
+ ret = 0;
+ break;
+ }
+ /* If lower 32 bits of SR, ignore non-user bits */
+ if (addr == offsetof (struct pt_regs, sr))
+ {
+ long cursr = get_stack_long(child, addr);
+ data &= ~(SR_MASK);
+ data |= (cursr & SR_MASK);
+ }
+ ret = put_stack_long(child, addr, data);
+ }
+ else if ((addr >= offsetof(struct user, fpu)) &&
+ (addr < offsetof(struct user, u_fpvalid))) {
+ unsigned long index;
+ ret = init_fpu(child);
+ if (ret)
+ break;
+ index = addr - offsetof(struct user, fpu);
+ ret = put_fpu_long(child, index, data);
+ }
+ break;
+
+ case PTRACE_GETREGS:
+ return copy_regset_to_user(child, &user_sh64_native_view,
+ REGSET_GENERAL,
+ 0, sizeof(struct pt_regs),
+ datap);
+ case PTRACE_SETREGS:
+ return copy_regset_from_user(child, &user_sh64_native_view,
+ REGSET_GENERAL,
+ 0, sizeof(struct pt_regs),
+ datap);
+#ifdef CONFIG_SH_FPU
+ case PTRACE_GETFPREGS:
+ return copy_regset_to_user(child, &user_sh64_native_view,
+ REGSET_FPU,
+ 0, sizeof(struct user_fpu_struct),
+ datap);
+ case PTRACE_SETFPREGS:
+ return copy_regset_from_user(child, &user_sh64_native_view,
+ REGSET_FPU,
+ 0, sizeof(struct user_fpu_struct),
+ datap);
+#endif
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+asmlinkage int sh64_ptrace(long request, long pid,
+ unsigned long addr, unsigned long data)
+{
+#define WPC_DBRMODE 0x0d104008
+ static unsigned long first_call;
+
+ if (!test_and_set_bit(0, &first_call)) {
+ /* Set WPC.DBRMODE to 0. This makes all debug events get
+ * delivered through RESVEC, i.e. into the handlers in entry.S.
+ * (If the kernel was downloaded using a remote gdb, WPC.DBRMODE
+ * would normally be left set to 1, which makes debug events get
+ * delivered through DBRVEC, i.e. into the remote gdb's
+ * handlers. This prevents ptrace getting them, and confuses
+ * the remote gdb.) */
+ printk("DBRMODE set to 0 to permit native debugging\n");
+ poke_real_address_q(WPC_DBRMODE, 0);
+ }
+
+ return sys_ptrace(request, pid, addr, data);
+}
+
+asmlinkage long long do_syscall_trace_enter(struct pt_regs *regs)
+{
+ long long ret = 0;
+
+ secure_computing_strict(regs->regs[9]);
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+ tracehook_report_syscall_entry(regs))
+ /*
+ * Tracing decided this syscall should not happen.
+ * We'll return a bogus call number to get an ENOSYS
+ * error, but leave the original number in regs->regs[0].
+ */
+ ret = -1LL;
+
+ if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
+ trace_sys_enter(regs, regs->regs[9]);
+
+ audit_syscall_entry(regs->regs[1], regs->regs[2], regs->regs[3],
+ regs->regs[4], regs->regs[5]);
+
+ return ret ?: regs->regs[9];
+}
+
+asmlinkage 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->regs[9]);
+
+ step = test_thread_flag(TIF_SINGLESTEP);
+ if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, step);
+}
+
+/* Called with interrupts disabled */
+asmlinkage void do_single_step(unsigned long long vec, struct pt_regs *regs)
+{
+ /* This is called after a single step exception (DEBUGSS).
+ There is no need to change the PC, as it is a post-execution
+ exception, as entry.S does not do anything to the PC for DEBUGSS.
+ We need to clear the Single Step setting in SR to avoid
+ continually stepping. */
+ local_irq_enable();
+ regs->sr &= ~SR_SSTEP;
+ force_sig(SIGTRAP, current);
+}
+
+/* Called with interrupts disabled */
+BUILD_TRAP_HANDLER(breakpoint)
+{
+ TRAP_HANDLER_DECL;
+
+ /* We need to forward step the PC, to counteract the backstep done
+ in signal.c. */
+ local_irq_enable();
+ force_sig(SIGTRAP, current);
+ regs->pc += 4;
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure single step bits etc are not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ user_disable_single_step(child);
+}