WSL2-Linux-Kernel/arch/mips/include/asm/ptrace.h

116 строки
3.0 KiB
C
Исходник Обычный вид История

/*
* 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.
*
* Copyright (C) 1994, 95, 96, 97, 98, 99, 2000 by Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
#ifndef _ASM_PTRACE_H
#define _ASM_PTRACE_H
#include <linux/compiler.h>
#include <linux/linkage.h>
#include <linux/types.h>
#include <asm/isadep.h>
#include <uapi/asm/ptrace.h>
/*
* This struct defines the way the registers are stored on the stack during a
* system call/exception. As usual the registers k0/k1 aren't being saved.
*/
struct pt_regs {
#ifdef CONFIG_32BIT
/* Pad bytes for argument save space on the stack. */
unsigned long pad0[6];
#endif
/* Saved main processor registers. */
unsigned long regs[32];
/* Saved special registers. */
unsigned long cp0_status;
unsigned long hi;
unsigned long lo;
#ifdef CONFIG_CPU_HAS_SMARTMIPS
unsigned long acx;
#endif
unsigned long cp0_badvaddr;
unsigned long cp0_cause;
unsigned long cp0_epc;
#ifdef CONFIG_MIPS_MT_SMTC
unsigned long cp0_tcstatus;
#endif /* CONFIG_MIPS_MT_SMTC */
#ifdef CONFIG_CPU_CAVIUM_OCTEON
unsigned long long mpl[3]; /* MTM{0,1,2} */
unsigned long long mtp[3]; /* MTP{0,1,2} */
#endif
} __aligned(8);
struct task_struct;
extern int ptrace_getregs(struct task_struct *child, __s64 __user *data);
extern int ptrace_setregs(struct task_struct *child, __s64 __user *data);
extern int ptrace_getfpregs(struct task_struct *child, __u32 __user *data);
extern int ptrace_setfpregs(struct task_struct *child, __u32 __user *data);
extern int ptrace_get_watch_regs(struct task_struct *child,
struct pt_watch_regs __user *addr);
extern int ptrace_set_watch_regs(struct task_struct *child,
struct pt_watch_regs __user *addr);
/*
* Does the process account for user or for system time?
*/
#define user_mode(regs) (((regs)->cp0_status & KU_MASK) == KU_USER)
Audit: push audit success and retcode into arch ptrace.h The audit system previously expected arches calling to audit_syscall_exit to supply as arguments if the syscall was a success and what the return code was. Audit also provides a helper AUDITSC_RESULT which was supposed to simplify things by converting from negative retcodes to an audit internal magic value stating success or failure. This helper was wrong and could indicate that a valid pointer returned to userspace was a failed syscall. The fix is to fix the layering foolishness. We now pass audit_syscall_exit a struct pt_reg and it in turns calls back into arch code to collect the return value and to determine if the syscall was a success or failure. We also define a generic is_syscall_success() macro which determines success/failure based on if the value is < -MAX_ERRNO. This works for arches like x86 which do not use a separate mechanism to indicate syscall failure. We make both the is_syscall_success() and regs_return_value() static inlines instead of macros. The reason is because the audit function must take a void* for the regs. (uml calls theirs struct uml_pt_regs instead of just struct pt_regs so audit_syscall_exit can't take a struct pt_regs). Since the audit function takes a void* we need to use static inlines to cast it back to the arch correct structure to dereference it. The other major change is that on some arches, like ia64, MIPS and ppc, we change regs_return_value() to give us the negative value on syscall failure. THE only other user of this macro, kretprobe_example.c, won't notice and it makes the value signed consistently for the audit functions across all archs. In arch/sh/kernel/ptrace_64.c I see that we were using regs[9] in the old audit code as the return value. But the ptrace_64.h code defined the macro regs_return_value() as regs[3]. I have no idea which one is correct, but this patch now uses the regs_return_value() function, so it now uses regs[3]. For powerpc we previously used regs->result but now use the regs_return_value() function which uses regs->gprs[3]. regs->gprs[3] is always positive so the regs_return_value(), much like ia64 makes it negative before calling the audit code when appropriate. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: H. Peter Anvin <hpa@zytor.com> [for x86 portion] Acked-by: Tony Luck <tony.luck@intel.com> [for ia64] Acked-by: Richard Weinberger <richard@nod.at> [for uml] Acked-by: David S. Miller <davem@davemloft.net> [for sparc] Acked-by: Ralf Baechle <ralf@linux-mips.org> [for mips] Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [for ppc]
2012-01-03 23:23:06 +04:00
static inline int is_syscall_success(struct pt_regs *regs)
{
return !regs->regs[7];
}
static inline long regs_return_value(struct pt_regs *regs)
{
if (is_syscall_success(regs))
return regs->regs[2];
else
return -regs->regs[2];
}
#define instruction_pointer(regs) ((regs)->cp0_epc)
#define profile_pc(regs) instruction_pointer(regs)
extern asmlinkage long syscall_trace_enter(struct pt_regs *regs);
extern asmlinkage void syscall_trace_leave(struct pt_regs *regs);
extern void die(const char *, struct pt_regs *) __noreturn;
static inline void die_if_kernel(const char *str, struct pt_regs *regs)
{
if (unlikely(!user_mode(regs)))
die(str, regs);
}
#define current_pt_regs() \
({ \
unsigned long sp = (unsigned long)__builtin_frame_address(0); \
(struct pt_regs *)((sp | (THREAD_SIZE - 1)) + 1 - 32) - 1; \
})
/* Helpers for working with the user stack pointer */
static inline unsigned long user_stack_pointer(struct pt_regs *regs)
{
return regs->regs[29];
}
static inline void user_stack_pointer_set(struct pt_regs *regs,
unsigned long val)
{
regs->regs[29] = val;
}
#endif /* _ASM_PTRACE_H */