| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * 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 |
| */ |
| #include <linux/kernel.h> |
| #include <linux/rwsem.h> |
| #include <linux/sched.h> |
| #include <linux/sched/task_stack.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 <linux/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, |
| ®s->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, |
| ®s->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); |
| } |
| |
| /* 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); |
| 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); |
| } |