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Diffstat (limited to '')
-rw-r--r-- | arch/sh/kernel/ptrace_64.c | 579 |
1 files changed, 579 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..1e0656d9e --- /dev/null +++ b/arch/sh/kernel/ptrace_64.c @@ -0,0 +1,579 @@ +/* + * 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/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, 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); +} |