kernel_optimize_test/include/asm-powerpc/kprobes.h
Tejun Heo 9281acea6a kallsyms: make KSYM_NAME_LEN include space for trailing '\0'
KSYM_NAME_LEN is peculiar in that it does not include the space for the
trailing '\0', forcing all users to use KSYM_NAME_LEN + 1 when allocating
buffer.  This is nonsense and error-prone.  Moreover, when the caller
forgets that it's very likely to subtly bite back by corrupting the stack
because the last position of the buffer is always cleared to zero.

This patch increments KSYM_NAME_LEN by one and updates code accordingly.

* off-by-one bug in asm-powerpc/kprobes.h::kprobe_lookup_name() macro
  is fixed.

* Where MODULE_NAME_LEN and KSYM_NAME_LEN were used together,
  MODULE_NAME_LEN was treated as if it didn't include space for the
  trailing '\0'.  Fix it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Paulo Marques <pmarques@grupopie.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:03 -07:00

122 lines
3.9 KiB
C

#ifndef _ASM_POWERPC_KPROBES_H
#define _ASM_POWERPC_KPROBES_H
#ifdef __KERNEL__
/*
* Kernel Probes (KProbes)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright (C) IBM Corporation, 2002, 2004
*
* 2002-Oct Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
* Probes initial implementation ( includes suggestions from
* Rusty Russell).
* 2004-Nov Modified for PPC64 by Ananth N Mavinakayanahalli
* <ananth@in.ibm.com>
*/
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/percpu.h>
#define __ARCH_WANT_KPROBES_INSN_SLOT
struct pt_regs;
struct kprobe;
typedef unsigned int kprobe_opcode_t;
#define BREAKPOINT_INSTRUCTION 0x7fe00008 /* trap */
#define MAX_INSN_SIZE 1
#define IS_TW(instr) (((instr) & 0xfc0007fe) == 0x7c000008)
#define IS_TD(instr) (((instr) & 0xfc0007fe) == 0x7c000088)
#define IS_TDI(instr) (((instr) & 0xfc000000) == 0x08000000)
#define IS_TWI(instr) (((instr) & 0xfc000000) == 0x0c000000)
#ifdef CONFIG_PPC64
/*
* 64bit powerpc uses function descriptors.
* Handle cases where:
* - User passes a <.symbol> or <module:.symbol>
* - User passes a <symbol> or <module:symbol>
* - User passes a non-existant symbol, kallsyms_lookup_name
* returns 0. Don't deref the NULL pointer in that case
*/
#define kprobe_lookup_name(name, addr) \
{ \
addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \
if (addr) { \
char *colon; \
if ((colon = strchr(name, ':')) != NULL) { \
colon++; \
if (*colon != '\0' && *colon != '.') \
addr = *(kprobe_opcode_t **)addr; \
} else if (name[0] != '.') \
addr = *(kprobe_opcode_t **)addr; \
} else { \
char dot_name[KSYM_NAME_LEN]; \
dot_name[0] = '.'; \
dot_name[1] = '\0'; \
strncat(dot_name, name, KSYM_NAME_LEN - 2); \
addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); \
} \
}
#define JPROBE_ENTRY(pentry) (kprobe_opcode_t *)((func_descr_t *)pentry)
#define is_trap(instr) (IS_TW(instr) || IS_TD(instr) || \
IS_TWI(instr) || IS_TDI(instr))
#else
/* Use stock kprobe_lookup_name since ppc32 doesn't use function descriptors */
#define JPROBE_ENTRY(pentry) (kprobe_opcode_t *)(pentry)
#define is_trap(instr) (IS_TW(instr) || IS_TWI(instr))
#endif
#define ARCH_SUPPORTS_KRETPROBES
#define ARCH_INACTIVE_KPROBE_COUNT 1
#define flush_insn_slot(p) do { } while (0)
void kretprobe_trampoline(void);
extern void arch_remove_kprobe(struct kprobe *p);
/* Architecture specific copy of original instruction */
struct arch_specific_insn {
/* copy of original instruction */
kprobe_opcode_t *insn;
/*
* Set in kprobes code, initially to 0. If the instruction can be
* eumulated, this is set to 1, if not, to -1.
*/
int boostable;
};
struct prev_kprobe {
struct kprobe *kp;
unsigned long status;
unsigned long saved_msr;
};
/* per-cpu kprobe control block */
struct kprobe_ctlblk {
unsigned long kprobe_status;
unsigned long kprobe_saved_msr;
struct pt_regs jprobe_saved_regs;
struct prev_kprobe prev_kprobe;
};
extern int kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data);
extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_KPROBES_H */