diff options
Diffstat (limited to 'arch/um/kernel/ptrace.c')
| -rw-r--r-- | arch/um/kernel/ptrace.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c new file mode 100644 index 000000000..5154b27de --- /dev/null +++ b/arch/um/kernel/ptrace.c @@ -0,0 +1,157 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) + */ + +#include <linux/audit.h> +#include <linux/ptrace.h> +#include <linux/sched.h> +#include <linux/uaccess.h> +#include <asm/ptrace-abi.h> + +void user_enable_single_step(struct task_struct *child) +{ + set_tsk_thread_flag(child, TIF_SINGLESTEP); + child->thread.singlestep_syscall = 0; + +#ifdef SUBARCH_SET_SINGLESTEPPING + SUBARCH_SET_SINGLESTEPPING(child, 1); +#endif +} + +void user_disable_single_step(struct task_struct *child) +{ + clear_tsk_thread_flag(child, TIF_SINGLESTEP); + child->thread.singlestep_syscall = 0; + +#ifdef SUBARCH_SET_SINGLESTEPPING + SUBARCH_SET_SINGLESTEPPING(child, 0); +#endif +} + +/* + * Called by kernel/ptrace.c when detaching.. + */ +void ptrace_disable(struct task_struct *child) +{ + user_disable_single_step(child); +} + +extern int peek_user(struct task_struct * child, long addr, long data); +extern int poke_user(struct task_struct * child, long addr, long data); + +long arch_ptrace(struct task_struct *child, long request, + unsigned long addr, unsigned long data) +{ + int i, ret; + unsigned long __user *p = (void __user *)data; + void __user *vp = p; + + switch (request) { + /* read the word at location addr in the USER area. */ + case PTRACE_PEEKUSR: + ret = peek_user(child, addr, data); + break; + + /* write the word at location addr in the USER area */ + case PTRACE_POKEUSR: + ret = poke_user(child, addr, data); + break; + + case PTRACE_SYSEMU: + case PTRACE_SYSEMU_SINGLESTEP: + ret = -EIO; + break; + +#ifdef PTRACE_GETREGS + case PTRACE_GETREGS: { /* Get all gp regs from the child. */ + if (!access_ok(p, MAX_REG_OFFSET)) { + ret = -EIO; + break; + } + for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) { + __put_user(getreg(child, i), p); + p++; + } + ret = 0; + break; + } +#endif +#ifdef PTRACE_SETREGS + case PTRACE_SETREGS: { /* Set all gp regs in the child. */ + unsigned long tmp = 0; + if (!access_ok(p, MAX_REG_OFFSET)) { + ret = -EIO; + break; + } + for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) { + __get_user(tmp, p); + putreg(child, i, tmp); + p++; + } + ret = 0; + break; + } +#endif + case PTRACE_GET_THREAD_AREA: + ret = ptrace_get_thread_area(child, addr, vp); + break; + + case PTRACE_SET_THREAD_AREA: + ret = ptrace_set_thread_area(child, addr, vp); + break; + + default: + ret = ptrace_request(child, request, addr, data); + if (ret == -EIO) + ret = subarch_ptrace(child, request, addr, data); + break; + } + + return ret; +} + +static void send_sigtrap(struct uml_pt_regs *regs, int error_code) +{ + /* Send us the fake SIGTRAP */ + force_sig_fault(SIGTRAP, TRAP_BRKPT, + /* User-mode eip? */ + UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL); +} + +/* + * XXX Check TIF_SINGLESTEP for singlestepping check and + * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check + */ +int syscall_trace_enter(struct pt_regs *regs) +{ + audit_syscall_entry(UPT_SYSCALL_NR(®s->regs), + UPT_SYSCALL_ARG1(®s->regs), + UPT_SYSCALL_ARG2(®s->regs), + UPT_SYSCALL_ARG3(®s->regs), + UPT_SYSCALL_ARG4(®s->regs)); + + if (!test_thread_flag(TIF_SYSCALL_TRACE)) + return 0; + + return ptrace_report_syscall_entry(regs); +} + +void syscall_trace_leave(struct pt_regs *regs) +{ + int ptraced = current->ptrace; + + audit_syscall_exit(regs); + + /* Fake a debug trap */ + if (test_thread_flag(TIF_SINGLESTEP)) + send_sigtrap(®s->regs, 0); + + if (!test_thread_flag(TIF_SYSCALL_TRACE)) + return; + + ptrace_report_syscall_exit(regs, 0); + /* force do_signal() --> is_syscall() */ + if (ptraced & PT_PTRACED) + set_thread_flag(TIF_SIGPENDING); +} |