![Eric W. Biederman](/assets/img/avatar_default.png)
There are so many places that build struct siginfo by hand that at least one of them is bound to get it wrong. A handful of cases in the kernel arguably did just that when using the errno field of siginfo to pass no errno values to userspace. The usage is limited to a single si_code so at least does not mess up anything else. Encapsulate this questionable pattern in a helper function so that the userspace ABI is preserved. Update all of the places that use this pattern to use the new helper function. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
974 lines
23 KiB
C
974 lines
23 KiB
C
/*
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* linux/arch/arm/kernel/ptrace.c
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*
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* By Ross Biro 1/23/92
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* edited by Linus Torvalds
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* ARM modifications Copyright (C) 2000 Russell King
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/kernel.h>
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#include <linux/sched/signal.h>
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#include <linux/sched/task_stack.h>
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#include <linux/mm.h>
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#include <linux/elf.h>
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#include <linux/smp.h>
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#include <linux/ptrace.h>
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#include <linux/user.h>
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#include <linux/security.h>
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#include <linux/init.h>
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#include <linux/signal.h>
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#include <linux/uaccess.h>
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#include <linux/perf_event.h>
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#include <linux/hw_breakpoint.h>
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#include <linux/regset.h>
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#include <linux/audit.h>
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#include <linux/tracehook.h>
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#include <linux/unistd.h>
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#include <asm/pgtable.h>
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#include <asm/traps.h>
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#define CREATE_TRACE_POINTS
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#include <trace/events/syscalls.h>
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#define REG_PC 15
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#define REG_PSR 16
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/*
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* does not yet catch signals sent when the child dies.
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* in exit.c or in signal.c.
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*/
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#if 0
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/*
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* Breakpoint SWI instruction: SWI &9F0001
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*/
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#define BREAKINST_ARM 0xef9f0001
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#define BREAKINST_THUMB 0xdf00 /* fill this in later */
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#else
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/*
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* New breakpoints - use an undefined instruction. The ARM architecture
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* reference manual guarantees that the following instruction space
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* will produce an undefined instruction exception on all CPUs:
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*
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* ARM: xxxx 0111 1111 xxxx xxxx xxxx 1111 xxxx
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* Thumb: 1101 1110 xxxx xxxx
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*/
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#define BREAKINST_ARM 0xe7f001f0
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#define BREAKINST_THUMB 0xde01
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#endif
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struct pt_regs_offset {
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const char *name;
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int offset;
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};
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#define REG_OFFSET_NAME(r) \
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{.name = #r, .offset = offsetof(struct pt_regs, ARM_##r)}
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#define REG_OFFSET_END {.name = NULL, .offset = 0}
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static const struct pt_regs_offset regoffset_table[] = {
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REG_OFFSET_NAME(r0),
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REG_OFFSET_NAME(r1),
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REG_OFFSET_NAME(r2),
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REG_OFFSET_NAME(r3),
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REG_OFFSET_NAME(r4),
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REG_OFFSET_NAME(r5),
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REG_OFFSET_NAME(r6),
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REG_OFFSET_NAME(r7),
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REG_OFFSET_NAME(r8),
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REG_OFFSET_NAME(r9),
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REG_OFFSET_NAME(r10),
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REG_OFFSET_NAME(fp),
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REG_OFFSET_NAME(ip),
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REG_OFFSET_NAME(sp),
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REG_OFFSET_NAME(lr),
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REG_OFFSET_NAME(pc),
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REG_OFFSET_NAME(cpsr),
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REG_OFFSET_NAME(ORIG_r0),
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REG_OFFSET_END,
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};
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/**
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* regs_query_register_offset() - query register offset from its name
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* @name: the name of a register
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*
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* regs_query_register_offset() returns the offset of a register in struct
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* pt_regs from its name. If the name is invalid, this returns -EINVAL;
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*/
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int regs_query_register_offset(const char *name)
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{
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const struct pt_regs_offset *roff;
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for (roff = regoffset_table; roff->name != NULL; roff++)
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if (!strcmp(roff->name, name))
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return roff->offset;
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return -EINVAL;
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}
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/**
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* regs_query_register_name() - query register name from its offset
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* @offset: the offset of a register in struct pt_regs.
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*
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* regs_query_register_name() returns the name of a register from its
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* offset in struct pt_regs. If the @offset is invalid, this returns NULL;
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*/
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const char *regs_query_register_name(unsigned int offset)
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{
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const struct pt_regs_offset *roff;
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for (roff = regoffset_table; roff->name != NULL; roff++)
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if (roff->offset == offset)
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return roff->name;
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return NULL;
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}
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/**
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* regs_within_kernel_stack() - check the address in the stack
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* @regs: pt_regs which contains kernel stack pointer.
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* @addr: address which is checked.
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*
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* regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
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* If @addr is within the kernel stack, it returns true. If not, returns false.
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*/
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bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
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{
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return ((addr & ~(THREAD_SIZE - 1)) ==
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(kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1)));
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}
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/**
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* regs_get_kernel_stack_nth() - get Nth entry of the stack
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* @regs: pt_regs which contains kernel stack pointer.
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* @n: stack entry number.
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*
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* regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
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* is specified by @regs. If the @n th entry is NOT in the kernel stack,
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* this returns 0.
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*/
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unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
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{
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unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
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addr += n;
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if (regs_within_kernel_stack(regs, (unsigned long)addr))
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return *addr;
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else
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return 0;
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}
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/*
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* this routine will get a word off of the processes privileged stack.
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* the offset is how far from the base addr as stored in the THREAD.
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* this routine assumes that all the privileged stacks are in our
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* data space.
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*/
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static inline long get_user_reg(struct task_struct *task, int offset)
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{
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return task_pt_regs(task)->uregs[offset];
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}
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/*
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* this routine will put a word on the processes privileged stack.
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* the offset is how far from the base addr as stored in the THREAD.
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* this routine assumes that all the privileged stacks are in our
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* data space.
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*/
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static inline int
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put_user_reg(struct task_struct *task, int offset, long data)
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{
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struct pt_regs newregs, *regs = task_pt_regs(task);
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int ret = -EINVAL;
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newregs = *regs;
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newregs.uregs[offset] = data;
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if (valid_user_regs(&newregs)) {
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regs->uregs[offset] = data;
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ret = 0;
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}
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return ret;
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}
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/*
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* Called by kernel/ptrace.c when detaching..
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*/
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void ptrace_disable(struct task_struct *child)
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{
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/* Nothing to do. */
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}
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/*
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* Handle hitting a breakpoint.
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*/
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void ptrace_break(struct task_struct *tsk, struct pt_regs *regs)
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{
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siginfo_t info;
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info.si_signo = SIGTRAP;
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info.si_errno = 0;
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info.si_code = TRAP_BRKPT;
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info.si_addr = (void __user *)instruction_pointer(regs);
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force_sig_info(SIGTRAP, &info, tsk);
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}
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static int break_trap(struct pt_regs *regs, unsigned int instr)
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{
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ptrace_break(current, regs);
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return 0;
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}
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static struct undef_hook arm_break_hook = {
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.instr_mask = 0x0fffffff,
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.instr_val = 0x07f001f0,
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.cpsr_mask = PSR_T_BIT,
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.cpsr_val = 0,
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.fn = break_trap,
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};
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static struct undef_hook thumb_break_hook = {
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.instr_mask = 0xffff,
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.instr_val = 0xde01,
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.cpsr_mask = PSR_T_BIT,
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.cpsr_val = PSR_T_BIT,
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.fn = break_trap,
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};
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static struct undef_hook thumb2_break_hook = {
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.instr_mask = 0xffffffff,
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.instr_val = 0xf7f0a000,
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.cpsr_mask = PSR_T_BIT,
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.cpsr_val = PSR_T_BIT,
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.fn = break_trap,
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};
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static int __init ptrace_break_init(void)
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{
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register_undef_hook(&arm_break_hook);
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register_undef_hook(&thumb_break_hook);
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register_undef_hook(&thumb2_break_hook);
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return 0;
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}
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core_initcall(ptrace_break_init);
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/*
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* Read the word at offset "off" into the "struct user". We
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* actually access the pt_regs stored on the kernel stack.
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*/
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static int ptrace_read_user(struct task_struct *tsk, unsigned long off,
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unsigned long __user *ret)
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{
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unsigned long tmp;
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if (off & 3)
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return -EIO;
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tmp = 0;
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if (off == PT_TEXT_ADDR)
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tmp = tsk->mm->start_code;
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else if (off == PT_DATA_ADDR)
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tmp = tsk->mm->start_data;
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else if (off == PT_TEXT_END_ADDR)
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tmp = tsk->mm->end_code;
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else if (off < sizeof(struct pt_regs))
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tmp = get_user_reg(tsk, off >> 2);
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else if (off >= sizeof(struct user))
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return -EIO;
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return put_user(tmp, ret);
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}
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/*
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* Write the word at offset "off" into "struct user". We
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* actually access the pt_regs stored on the kernel stack.
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*/
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static int ptrace_write_user(struct task_struct *tsk, unsigned long off,
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unsigned long val)
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{
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if (off & 3 || off >= sizeof(struct user))
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return -EIO;
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if (off >= sizeof(struct pt_regs))
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return 0;
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return put_user_reg(tsk, off >> 2, val);
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}
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#ifdef CONFIG_IWMMXT
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/*
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* Get the child iWMMXt state.
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*/
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static int ptrace_getwmmxregs(struct task_struct *tsk, void __user *ufp)
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{
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struct thread_info *thread = task_thread_info(tsk);
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if (!test_ti_thread_flag(thread, TIF_USING_IWMMXT))
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return -ENODATA;
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iwmmxt_task_disable(thread); /* force it to ram */
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return copy_to_user(ufp, &thread->fpstate.iwmmxt, IWMMXT_SIZE)
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? -EFAULT : 0;
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}
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/*
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* Set the child iWMMXt state.
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*/
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static int ptrace_setwmmxregs(struct task_struct *tsk, void __user *ufp)
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{
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struct thread_info *thread = task_thread_info(tsk);
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if (!test_ti_thread_flag(thread, TIF_USING_IWMMXT))
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return -EACCES;
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iwmmxt_task_release(thread); /* force a reload */
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return copy_from_user(&thread->fpstate.iwmmxt, ufp, IWMMXT_SIZE)
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? -EFAULT : 0;
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}
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#endif
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#ifdef CONFIG_CRUNCH
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/*
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* Get the child Crunch state.
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*/
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static int ptrace_getcrunchregs(struct task_struct *tsk, void __user *ufp)
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{
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struct thread_info *thread = task_thread_info(tsk);
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crunch_task_disable(thread); /* force it to ram */
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return copy_to_user(ufp, &thread->crunchstate, CRUNCH_SIZE)
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? -EFAULT : 0;
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}
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/*
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* Set the child Crunch state.
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*/
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static int ptrace_setcrunchregs(struct task_struct *tsk, void __user *ufp)
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{
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struct thread_info *thread = task_thread_info(tsk);
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crunch_task_release(thread); /* force a reload */
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return copy_from_user(&thread->crunchstate, ufp, CRUNCH_SIZE)
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? -EFAULT : 0;
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}
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#endif
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#ifdef CONFIG_HAVE_HW_BREAKPOINT
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/*
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* Convert a virtual register number into an index for a thread_info
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* breakpoint array. Breakpoints are identified using positive numbers
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* whilst watchpoints are negative. The registers are laid out as pairs
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* of (address, control), each pair mapping to a unique hw_breakpoint struct.
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* Register 0 is reserved for describing resource information.
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*/
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static int ptrace_hbp_num_to_idx(long num)
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{
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if (num < 0)
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num = (ARM_MAX_BRP << 1) - num;
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return (num - 1) >> 1;
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}
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/*
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* Returns the virtual register number for the address of the
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* breakpoint at index idx.
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*/
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static long ptrace_hbp_idx_to_num(int idx)
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{
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long mid = ARM_MAX_BRP << 1;
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long num = (idx << 1) + 1;
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return num > mid ? mid - num : num;
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}
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/*
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* Handle hitting a HW-breakpoint.
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*/
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static void ptrace_hbptriggered(struct perf_event *bp,
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struct perf_sample_data *data,
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struct pt_regs *regs)
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{
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struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
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long num;
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int i;
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for (i = 0; i < ARM_MAX_HBP_SLOTS; ++i)
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if (current->thread.debug.hbp[i] == bp)
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break;
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num = (i == ARM_MAX_HBP_SLOTS) ? 0 : ptrace_hbp_idx_to_num(i);
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force_sig_ptrace_errno_trap((int)num, (void __user *)(bkpt->trigger));
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}
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/*
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* Set ptrace breakpoint pointers to zero for this task.
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* This is required in order to prevent child processes from unregistering
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* breakpoints held by their parent.
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*/
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void clear_ptrace_hw_breakpoint(struct task_struct *tsk)
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{
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memset(tsk->thread.debug.hbp, 0, sizeof(tsk->thread.debug.hbp));
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}
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/*
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* Unregister breakpoints from this task and reset the pointers in
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* the thread_struct.
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*/
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void flush_ptrace_hw_breakpoint(struct task_struct *tsk)
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{
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int i;
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struct thread_struct *t = &tsk->thread;
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for (i = 0; i < ARM_MAX_HBP_SLOTS; i++) {
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if (t->debug.hbp[i]) {
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unregister_hw_breakpoint(t->debug.hbp[i]);
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t->debug.hbp[i] = NULL;
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}
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}
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}
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static u32 ptrace_get_hbp_resource_info(void)
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{
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u8 num_brps, num_wrps, debug_arch, wp_len;
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u32 reg = 0;
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num_brps = hw_breakpoint_slots(TYPE_INST);
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num_wrps = hw_breakpoint_slots(TYPE_DATA);
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debug_arch = arch_get_debug_arch();
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wp_len = arch_get_max_wp_len();
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reg |= debug_arch;
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reg <<= 8;
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reg |= wp_len;
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reg <<= 8;
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reg |= num_wrps;
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reg <<= 8;
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reg |= num_brps;
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return reg;
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}
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|
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static struct perf_event *ptrace_hbp_create(struct task_struct *tsk, int type)
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{
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struct perf_event_attr attr;
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ptrace_breakpoint_init(&attr);
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/* Initialise fields to sane defaults. */
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attr.bp_addr = 0;
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attr.bp_len = HW_BREAKPOINT_LEN_4;
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attr.bp_type = type;
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attr.disabled = 1;
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return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL,
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tsk);
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}
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|
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static int ptrace_gethbpregs(struct task_struct *tsk, long num,
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unsigned long __user *data)
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{
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u32 reg;
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int idx, ret = 0;
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struct perf_event *bp;
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struct arch_hw_breakpoint_ctrl arch_ctrl;
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|
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if (num == 0) {
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reg = ptrace_get_hbp_resource_info();
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} else {
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idx = ptrace_hbp_num_to_idx(num);
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if (idx < 0 || idx >= ARM_MAX_HBP_SLOTS) {
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ret = -EINVAL;
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goto out;
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}
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bp = tsk->thread.debug.hbp[idx];
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if (!bp) {
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reg = 0;
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goto put;
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}
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arch_ctrl = counter_arch_bp(bp)->ctrl;
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/*
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* Fix up the len because we may have adjusted it
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* to compensate for an unaligned address.
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*/
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while (!(arch_ctrl.len & 0x1))
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arch_ctrl.len >>= 1;
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if (num & 0x1)
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reg = bp->attr.bp_addr;
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else
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reg = encode_ctrl_reg(arch_ctrl);
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}
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put:
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if (put_user(reg, data))
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ret = -EFAULT;
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|
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out:
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return ret;
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}
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|
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static int ptrace_sethbpregs(struct task_struct *tsk, long num,
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unsigned long __user *data)
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{
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int idx, gen_len, gen_type, implied_type, ret = 0;
|
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u32 user_val;
|
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struct perf_event *bp;
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struct arch_hw_breakpoint_ctrl ctrl;
|
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struct perf_event_attr attr;
|
|
|
|
if (num == 0)
|
|
goto out;
|
|
else if (num < 0)
|
|
implied_type = HW_BREAKPOINT_RW;
|
|
else
|
|
implied_type = HW_BREAKPOINT_X;
|
|
|
|
idx = ptrace_hbp_num_to_idx(num);
|
|
if (idx < 0 || idx >= ARM_MAX_HBP_SLOTS) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
if (get_user(user_val, data)) {
|
|
ret = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
bp = tsk->thread.debug.hbp[idx];
|
|
if (!bp) {
|
|
bp = ptrace_hbp_create(tsk, implied_type);
|
|
if (IS_ERR(bp)) {
|
|
ret = PTR_ERR(bp);
|
|
goto out;
|
|
}
|
|
tsk->thread.debug.hbp[idx] = bp;
|
|
}
|
|
|
|
attr = bp->attr;
|
|
|
|
if (num & 0x1) {
|
|
/* Address */
|
|
attr.bp_addr = user_val;
|
|
} else {
|
|
/* Control */
|
|
decode_ctrl_reg(user_val, &ctrl);
|
|
ret = arch_bp_generic_fields(ctrl, &gen_len, &gen_type);
|
|
if (ret)
|
|
goto out;
|
|
|
|
if ((gen_type & implied_type) != gen_type) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
attr.bp_len = gen_len;
|
|
attr.bp_type = gen_type;
|
|
attr.disabled = !ctrl.enabled;
|
|
}
|
|
|
|
ret = modify_user_hw_breakpoint(bp, &attr);
|
|
out:
|
|
return ret;
|
|
}
|
|
#endif
|
|
|
|
/* regset get/set implementations */
|
|
|
|
static int gpr_get(struct task_struct *target,
|
|
const struct user_regset *regset,
|
|
unsigned int pos, unsigned int count,
|
|
void *kbuf, void __user *ubuf)
|
|
{
|
|
struct pt_regs *regs = task_pt_regs(target);
|
|
|
|
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
|
|
regs,
|
|
0, sizeof(*regs));
|
|
}
|
|
|
|
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)
|
|
{
|
|
int ret;
|
|
struct pt_regs newregs = *task_pt_regs(target);
|
|
|
|
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
|
|
&newregs,
|
|
0, sizeof(newregs));
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (!valid_user_regs(&newregs))
|
|
return -EINVAL;
|
|
|
|
*task_pt_regs(target) = newregs;
|
|
return 0;
|
|
}
|
|
|
|
static int fpa_get(struct task_struct *target,
|
|
const struct user_regset *regset,
|
|
unsigned int pos, unsigned int count,
|
|
void *kbuf, void __user *ubuf)
|
|
{
|
|
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
|
|
&task_thread_info(target)->fpstate,
|
|
0, sizeof(struct user_fp));
|
|
}
|
|
|
|
static int fpa_set(struct task_struct *target,
|
|
const struct user_regset *regset,
|
|
unsigned int pos, unsigned int count,
|
|
const void *kbuf, const void __user *ubuf)
|
|
{
|
|
struct thread_info *thread = task_thread_info(target);
|
|
|
|
thread->used_cp[1] = thread->used_cp[2] = 1;
|
|
|
|
return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
|
|
&thread->fpstate,
|
|
0, sizeof(struct user_fp));
|
|
}
|
|
|
|
#ifdef CONFIG_VFP
|
|
/*
|
|
* VFP register get/set implementations.
|
|
*
|
|
* With respect to the kernel, struct user_fp is divided into three chunks:
|
|
* 16 or 32 real VFP registers (d0-d15 or d0-31)
|
|
* These are transferred to/from the real registers in the task's
|
|
* vfp_hard_struct. The number of registers depends on the kernel
|
|
* configuration.
|
|
*
|
|
* 16 or 0 fake VFP registers (d16-d31 or empty)
|
|
* i.e., the user_vfp structure has space for 32 registers even if
|
|
* the kernel doesn't have them all.
|
|
*
|
|
* vfp_get() reads this chunk as zero where applicable
|
|
* vfp_set() ignores this chunk
|
|
*
|
|
* 1 word for the FPSCR
|
|
*
|
|
* The bounds-checking logic built into user_regset_copyout and friends
|
|
* means that we can make a simple sequence of calls to map the relevant data
|
|
* to/from the specified slice of the user regset structure.
|
|
*/
|
|
static int vfp_get(struct task_struct *target,
|
|
const struct user_regset *regset,
|
|
unsigned int pos, unsigned int count,
|
|
void *kbuf, void __user *ubuf)
|
|
{
|
|
int ret;
|
|
struct thread_info *thread = task_thread_info(target);
|
|
struct vfp_hard_struct const *vfp = &thread->vfpstate.hard;
|
|
const size_t user_fpregs_offset = offsetof(struct user_vfp, fpregs);
|
|
const size_t user_fpscr_offset = offsetof(struct user_vfp, fpscr);
|
|
|
|
vfp_sync_hwstate(thread);
|
|
|
|
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
|
|
&vfp->fpregs,
|
|
user_fpregs_offset,
|
|
user_fpregs_offset + sizeof(vfp->fpregs));
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
|
|
user_fpregs_offset + sizeof(vfp->fpregs),
|
|
user_fpscr_offset);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
|
|
&vfp->fpscr,
|
|
user_fpscr_offset,
|
|
user_fpscr_offset + sizeof(vfp->fpscr));
|
|
}
|
|
|
|
/*
|
|
* For vfp_set() a read-modify-write is done on the VFP registers,
|
|
* in order to avoid writing back a half-modified set of registers on
|
|
* failure.
|
|
*/
|
|
static int vfp_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;
|
|
struct thread_info *thread = task_thread_info(target);
|
|
struct vfp_hard_struct new_vfp;
|
|
const size_t user_fpregs_offset = offsetof(struct user_vfp, fpregs);
|
|
const size_t user_fpscr_offset = offsetof(struct user_vfp, fpscr);
|
|
|
|
vfp_sync_hwstate(thread);
|
|
new_vfp = thread->vfpstate.hard;
|
|
|
|
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
|
|
&new_vfp.fpregs,
|
|
user_fpregs_offset,
|
|
user_fpregs_offset + sizeof(new_vfp.fpregs));
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
|
|
user_fpregs_offset + sizeof(new_vfp.fpregs),
|
|
user_fpscr_offset);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
|
|
&new_vfp.fpscr,
|
|
user_fpscr_offset,
|
|
user_fpscr_offset + sizeof(new_vfp.fpscr));
|
|
if (ret)
|
|
return ret;
|
|
|
|
thread->vfpstate.hard = new_vfp;
|
|
vfp_flush_hwstate(thread);
|
|
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_VFP */
|
|
|
|
enum arm_regset {
|
|
REGSET_GPR,
|
|
REGSET_FPR,
|
|
#ifdef CONFIG_VFP
|
|
REGSET_VFP,
|
|
#endif
|
|
};
|
|
|
|
static const struct user_regset arm_regsets[] = {
|
|
[REGSET_GPR] = {
|
|
.core_note_type = NT_PRSTATUS,
|
|
.n = ELF_NGREG,
|
|
.size = sizeof(u32),
|
|
.align = sizeof(u32),
|
|
.get = gpr_get,
|
|
.set = gpr_set
|
|
},
|
|
[REGSET_FPR] = {
|
|
/*
|
|
* For the FPA regs in fpstate, the real fields are a mixture
|
|
* of sizes, so pretend that the registers are word-sized:
|
|
*/
|
|
.core_note_type = NT_PRFPREG,
|
|
.n = sizeof(struct user_fp) / sizeof(u32),
|
|
.size = sizeof(u32),
|
|
.align = sizeof(u32),
|
|
.get = fpa_get,
|
|
.set = fpa_set
|
|
},
|
|
#ifdef CONFIG_VFP
|
|
[REGSET_VFP] = {
|
|
/*
|
|
* Pretend that the VFP regs are word-sized, since the FPSCR is
|
|
* a single word dangling at the end of struct user_vfp:
|
|
*/
|
|
.core_note_type = NT_ARM_VFP,
|
|
.n = ARM_VFPREGS_SIZE / sizeof(u32),
|
|
.size = sizeof(u32),
|
|
.align = sizeof(u32),
|
|
.get = vfp_get,
|
|
.set = vfp_set
|
|
},
|
|
#endif /* CONFIG_VFP */
|
|
};
|
|
|
|
static const struct user_regset_view user_arm_view = {
|
|
.name = "arm", .e_machine = ELF_ARCH, .ei_osabi = ELF_OSABI,
|
|
.regsets = arm_regsets, .n = ARRAY_SIZE(arm_regsets)
|
|
};
|
|
|
|
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
|
|
{
|
|
return &user_arm_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) {
|
|
case PTRACE_PEEKUSR:
|
|
ret = ptrace_read_user(child, addr, datap);
|
|
break;
|
|
|
|
case PTRACE_POKEUSR:
|
|
ret = ptrace_write_user(child, addr, data);
|
|
break;
|
|
|
|
case PTRACE_GETREGS:
|
|
ret = copy_regset_to_user(child,
|
|
&user_arm_view, REGSET_GPR,
|
|
0, sizeof(struct pt_regs),
|
|
datap);
|
|
break;
|
|
|
|
case PTRACE_SETREGS:
|
|
ret = copy_regset_from_user(child,
|
|
&user_arm_view, REGSET_GPR,
|
|
0, sizeof(struct pt_regs),
|
|
datap);
|
|
break;
|
|
|
|
case PTRACE_GETFPREGS:
|
|
ret = copy_regset_to_user(child,
|
|
&user_arm_view, REGSET_FPR,
|
|
0, sizeof(union fp_state),
|
|
datap);
|
|
break;
|
|
|
|
case PTRACE_SETFPREGS:
|
|
ret = copy_regset_from_user(child,
|
|
&user_arm_view, REGSET_FPR,
|
|
0, sizeof(union fp_state),
|
|
datap);
|
|
break;
|
|
|
|
#ifdef CONFIG_IWMMXT
|
|
case PTRACE_GETWMMXREGS:
|
|
ret = ptrace_getwmmxregs(child, datap);
|
|
break;
|
|
|
|
case PTRACE_SETWMMXREGS:
|
|
ret = ptrace_setwmmxregs(child, datap);
|
|
break;
|
|
#endif
|
|
|
|
case PTRACE_GET_THREAD_AREA:
|
|
ret = put_user(task_thread_info(child)->tp_value[0],
|
|
datap);
|
|
break;
|
|
|
|
case PTRACE_SET_SYSCALL:
|
|
task_thread_info(child)->syscall = data;
|
|
ret = 0;
|
|
break;
|
|
|
|
#ifdef CONFIG_CRUNCH
|
|
case PTRACE_GETCRUNCHREGS:
|
|
ret = ptrace_getcrunchregs(child, datap);
|
|
break;
|
|
|
|
case PTRACE_SETCRUNCHREGS:
|
|
ret = ptrace_setcrunchregs(child, datap);
|
|
break;
|
|
#endif
|
|
|
|
#ifdef CONFIG_VFP
|
|
case PTRACE_GETVFPREGS:
|
|
ret = copy_regset_to_user(child,
|
|
&user_arm_view, REGSET_VFP,
|
|
0, ARM_VFPREGS_SIZE,
|
|
datap);
|
|
break;
|
|
|
|
case PTRACE_SETVFPREGS:
|
|
ret = copy_regset_from_user(child,
|
|
&user_arm_view, REGSET_VFP,
|
|
0, ARM_VFPREGS_SIZE,
|
|
datap);
|
|
break;
|
|
#endif
|
|
|
|
#ifdef CONFIG_HAVE_HW_BREAKPOINT
|
|
case PTRACE_GETHBPREGS:
|
|
ret = ptrace_gethbpregs(child, addr,
|
|
(unsigned long __user *)data);
|
|
break;
|
|
case PTRACE_SETHBPREGS:
|
|
ret = ptrace_sethbpregs(child, addr,
|
|
(unsigned long __user *)data);
|
|
break;
|
|
#endif
|
|
|
|
default:
|
|
ret = ptrace_request(child, request, addr, data);
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
enum ptrace_syscall_dir {
|
|
PTRACE_SYSCALL_ENTER = 0,
|
|
PTRACE_SYSCALL_EXIT,
|
|
};
|
|
|
|
static void tracehook_report_syscall(struct pt_regs *regs,
|
|
enum ptrace_syscall_dir dir)
|
|
{
|
|
unsigned long ip;
|
|
|
|
/*
|
|
* IP is used to denote syscall entry/exit:
|
|
* IP = 0 -> entry, =1 -> exit
|
|
*/
|
|
ip = regs->ARM_ip;
|
|
regs->ARM_ip = dir;
|
|
|
|
if (dir == PTRACE_SYSCALL_EXIT)
|
|
tracehook_report_syscall_exit(regs, 0);
|
|
else if (tracehook_report_syscall_entry(regs))
|
|
current_thread_info()->syscall = -1;
|
|
|
|
regs->ARM_ip = ip;
|
|
}
|
|
|
|
asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno)
|
|
{
|
|
current_thread_info()->syscall = scno;
|
|
|
|
if (test_thread_flag(TIF_SYSCALL_TRACE))
|
|
tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);
|
|
|
|
/* Do seccomp after ptrace; syscall may have changed. */
|
|
#ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER
|
|
if (secure_computing(NULL) == -1)
|
|
return -1;
|
|
#else
|
|
/* XXX: remove this once OABI gets fixed */
|
|
secure_computing_strict(current_thread_info()->syscall);
|
|
#endif
|
|
|
|
/* Tracer or seccomp may have changed syscall. */
|
|
scno = current_thread_info()->syscall;
|
|
|
|
if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
|
|
trace_sys_enter(regs, scno);
|
|
|
|
audit_syscall_entry(scno, regs->ARM_r0, regs->ARM_r1, regs->ARM_r2,
|
|
regs->ARM_r3);
|
|
|
|
return scno;
|
|
}
|
|
|
|
asmlinkage void syscall_trace_exit(struct pt_regs *regs)
|
|
{
|
|
/*
|
|
* Audit the syscall before anything else, as a debugger may
|
|
* come in and change the current registers.
|
|
*/
|
|
audit_syscall_exit(regs);
|
|
|
|
/*
|
|
* Note that we haven't updated the ->syscall field for the
|
|
* current thread. This isn't a problem because it will have
|
|
* been set on syscall entry and there hasn't been an opportunity
|
|
* for a PTRACE_SET_SYSCALL since then.
|
|
*/
|
|
if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
|
|
trace_sys_exit(regs, regs_return_value(regs));
|
|
|
|
if (test_thread_flag(TIF_SYSCALL_TRACE))
|
|
tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
|
|
}
|