Initial import

1 files changed, 496 insertions, 0 deletions

diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
new file mode 100644
index 000000000..1ab54754a
--- /dev/null
+++ b/include/linux/kprobes.h
@@ -0,0 +1,496 @@
+#ifndef _LINUX_KPROBES_H
+#define _LINUX_KPROBES_H
+/*
+ *  Kernel Probes (KProbes)
+ *  include/linux/kprobes.h
+ *
+ * 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-July	Suparna Bhattacharya <suparna@in.ibm.com> added jumper probes
+ *		interface to access function arguments.
+ * 2005-May	Hien Nguyen <hien@us.ibm.com> and Jim Keniston
+ *		<jkenisto@us.ibm.com>  and Prasanna S Panchamukhi
+ *		<prasanna@in.ibm.com> added function-return probes.
+ */
+#include <linux/compiler.h>	/* for __kprobes */
+#include <linux/linkage.h>
+#include <linux/list.h>
+#include <linux/notifier.h>
+#include <linux/smp.h>
+#include <linux/bug.h>
+#include <linux/percpu.h>
+#include <linux/spinlock.h>
+#include <linux/rcupdate.h>
+#include <linux/mutex.h>
+#include <linux/ftrace.h>
+
+#ifdef CONFIG_KPROBES
+#include <asm/kprobes.h>
+
+/* kprobe_status settings */
+#define KPROBE_HIT_ACTIVE	0x00000001
+#define KPROBE_HIT_SS		0x00000002
+#define KPROBE_REENTER		0x00000004
+#define KPROBE_HIT_SSDONE	0x00000008
+
+#else /* CONFIG_KPROBES */
+typedef int kprobe_opcode_t;
+struct arch_specific_insn {
+	int dummy;
+};
+#endif /* CONFIG_KPROBES */
+
+struct kprobe;
+struct pt_regs;
+struct kretprobe;
+struct kretprobe_instance;
+typedef int (*kprobe_pre_handler_t) (struct kprobe *, struct pt_regs *);
+typedef int (*kprobe_break_handler_t) (struct kprobe *, struct pt_regs *);
+typedef void (*kprobe_post_handler_t) (struct kprobe *, struct pt_regs *,
+				       unsigned long flags);
+typedef int (*kprobe_fault_handler_t) (struct kprobe *, struct pt_regs *,
+				       int trapnr);
+typedef int (*kretprobe_handler_t) (struct kretprobe_instance *,
+				    struct pt_regs *);
+
+struct kprobe {
+	struct hlist_node hlist;
+
+	/* list of kprobes for multi-handler support */
+	struct list_head list;
+
+	/*count the number of times this probe was temporarily disarmed */
+	unsigned long nmissed;
+
+	/* location of the probe point */
+	kprobe_opcode_t *addr;
+
+	/* Allow user to indicate symbol name of the probe point */
+	const char *symbol_name;
+
+	/* Offset into the symbol */
+	unsigned int offset;
+
+	/* Called before addr is executed. */
+	kprobe_pre_handler_t pre_handler;
+
+	/* Called after addr is executed, unless... */
+	kprobe_post_handler_t post_handler;
+
+	/*
+	 * ... called if executing addr causes a fault (eg. page fault).
+	 * Return 1 if it handled fault, otherwise kernel will see it.
+	 */
+	kprobe_fault_handler_t fault_handler;
+
+	/*
+	 * ... called if breakpoint trap occurs in probe handler.
+	 * Return 1 if it handled break, otherwise kernel will see it.
+	 */
+	kprobe_break_handler_t break_handler;
+
+	/* Saved opcode (which has been replaced with breakpoint) */
+	kprobe_opcode_t opcode;
+
+	/* copy of the original instruction */
+	struct arch_specific_insn ainsn;
+
+	/*
+	 * Indicates various status flags.
+	 * Protected by kprobe_mutex after this kprobe is registered.
+	 */
+	u32 flags;
+};
+
+/* Kprobe status flags */
+#define KPROBE_FLAG_GONE	1 /* breakpoint has already gone */
+#define KPROBE_FLAG_DISABLED	2 /* probe is temporarily disabled */
+#define KPROBE_FLAG_OPTIMIZED	4 /*
+				   * probe is really optimized.
+				   * NOTE:
+				   * this flag is only for optimized_kprobe.
+				   */
+#define KPROBE_FLAG_FTRACE	8 /* probe is using ftrace */
+
+/* Has this kprobe gone ? */
+static inline int kprobe_gone(struct kprobe *p)
+{
+	return p->flags & KPROBE_FLAG_GONE;
+}
+
+/* Is this kprobe disabled ? */
+static inline int kprobe_disabled(struct kprobe *p)
+{
+	return p->flags & (KPROBE_FLAG_DISABLED | KPROBE_FLAG_GONE);
+}
+
+/* Is this kprobe really running optimized path ? */
+static inline int kprobe_optimized(struct kprobe *p)
+{
+	return p->flags & KPROBE_FLAG_OPTIMIZED;
+}
+
+/* Is this kprobe uses ftrace ? */
+static inline int kprobe_ftrace(struct kprobe *p)
+{
+	return p->flags & KPROBE_FLAG_FTRACE;
+}
+
+/*
+ * Special probe type that uses setjmp-longjmp type tricks to resume
+ * execution at a specified entry with a matching prototype corresponding
+ * to the probed function - a trick to enable arguments to become
+ * accessible seamlessly by probe handling logic.
+ * Note:
+ * Because of the way compilers allocate stack space for local variables
+ * etc upfront, regardless of sub-scopes within a function, this mirroring
+ * principle currently works only for probes placed on function entry points.
+ */
+struct jprobe {
+	struct kprobe kp;
+	void *entry;	/* probe handling code to jump to */
+};
+
+/* For backward compatibility with old code using JPROBE_ENTRY() */
+#define JPROBE_ENTRY(handler)	(handler)
+
+/*
+ * Function-return probe -
+ * Note:
+ * User needs to provide a handler function, and initialize maxactive.
+ * maxactive - The maximum number of instances of the probed function that
+ * can be active concurrently.
+ * nmissed - tracks the number of times the probed function's return was
+ * ignored, due to maxactive being too low.
+ *
+ */
+struct kretprobe {
+	struct kprobe kp;
+	kretprobe_handler_t handler;
+	kretprobe_handler_t entry_handler;
+	int maxactive;
+	int nmissed;
+	size_t data_size;
+	struct hlist_head free_instances;
+	raw_spinlock_t lock;
+};
+
+struct kretprobe_instance {
+	struct hlist_node hlist;
+	struct kretprobe *rp;
+	kprobe_opcode_t *ret_addr;
+	struct task_struct *task;
+	char data[0];
+};
+
+struct kretprobe_blackpoint {
+	const char *name;
+	void *addr;
+};
+
+struct kprobe_blacklist_entry {
+	struct list_head list;
+	unsigned long start_addr;
+	unsigned long end_addr;
+};
+
+#ifdef CONFIG_KPROBES
+DECLARE_PER_CPU(struct kprobe *, current_kprobe);
+DECLARE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
+
+/*
+ * For #ifdef avoidance:
+ */
+static inline int kprobes_built_in(void)
+{
+	return 1;
+}
+
+#ifdef CONFIG_KRETPROBES
+extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
+				   struct pt_regs *regs);
+extern int arch_trampoline_kprobe(struct kprobe *p);
+#else /* CONFIG_KRETPROBES */
+static inline void arch_prepare_kretprobe(struct kretprobe *rp,
+					struct pt_regs *regs)
+{
+}
+static inline int arch_trampoline_kprobe(struct kprobe *p)
+{
+	return 0;
+}
+#endif /* CONFIG_KRETPROBES */
+
+extern struct kretprobe_blackpoint kretprobe_blacklist[];
+
+static inline void kretprobe_assert(struct kretprobe_instance *ri,
+	unsigned long orig_ret_address, unsigned long trampoline_address)
+{
+	if (!orig_ret_address || (orig_ret_address == trampoline_address)) {
+		printk("kretprobe BUG!: Processing kretprobe %p @ %p\n",
+				ri->rp, ri->rp->kp.addr);
+		BUG();
+	}
+}
+
+#ifdef CONFIG_KPROBES_SANITY_TEST
+extern int init_test_probes(void);
+#else
+static inline int init_test_probes(void)
+{
+	return 0;
+}
+#endif /* CONFIG_KPROBES_SANITY_TEST */
+
+extern int arch_prepare_kprobe(struct kprobe *p);
+extern void arch_arm_kprobe(struct kprobe *p);
+extern void arch_disarm_kprobe(struct kprobe *p);
+extern int arch_init_kprobes(void);
+extern void show_registers(struct pt_regs *regs);
+extern void kprobes_inc_nmissed_count(struct kprobe *p);
+extern bool arch_within_kprobe_blacklist(unsigned long addr);
+
+struct kprobe_insn_cache {
+	struct mutex mutex;
+	void *(*alloc)(void);	/* allocate insn page */
+	void (*free)(void *);	/* free insn page */
+	struct list_head pages; /* list of kprobe_insn_page */
+	size_t insn_size;	/* size of instruction slot */
+	int nr_garbage;
+};
+
+extern kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c);
+extern void __free_insn_slot(struct kprobe_insn_cache *c,
+			     kprobe_opcode_t *slot, int dirty);
+
+#define DEFINE_INSN_CACHE_OPS(__name)					\
+extern struct kprobe_insn_cache kprobe_##__name##_slots;		\
+									\
+static inline kprobe_opcode_t *get_##__name##_slot(void)		\
+{									\
+	return __get_insn_slot(&kprobe_##__name##_slots);		\
+}									\
+									\
+static inline void free_##__name##_slot(kprobe_opcode_t *slot, int dirty)\
+{									\
+	__free_insn_slot(&kprobe_##__name##_slots, slot, dirty);	\
+}									\
+
+DEFINE_INSN_CACHE_OPS(insn);
+
+#ifdef CONFIG_OPTPROBES
+/*
+ * Internal structure for direct jump optimized probe
+ */
+struct optimized_kprobe {
+	struct kprobe kp;
+	struct list_head list;	/* list for optimizing queue */
+	struct arch_optimized_insn optinsn;
+};
+
+/* Architecture dependent functions for direct jump optimization */
+extern int arch_prepared_optinsn(struct arch_optimized_insn *optinsn);
+extern int arch_check_optimized_kprobe(struct optimized_kprobe *op);
+extern int arch_prepare_optimized_kprobe(struct optimized_kprobe *op,
+					 struct kprobe *orig);
+extern void arch_remove_optimized_kprobe(struct optimized_kprobe *op);
+extern void arch_optimize_kprobes(struct list_head *oplist);
+extern void arch_unoptimize_kprobes(struct list_head *oplist,
+				    struct list_head *done_list);
+extern void arch_unoptimize_kprobe(struct optimized_kprobe *op);
+extern int arch_within_optimized_kprobe(struct optimized_kprobe *op,
+					unsigned long addr);
+
+extern void opt_pre_handler(struct kprobe *p, struct pt_regs *regs);
+
+DEFINE_INSN_CACHE_OPS(optinsn);
+
+#ifdef CONFIG_SYSCTL
+extern int sysctl_kprobes_optimization;
+extern int proc_kprobes_optimization_handler(struct ctl_table *table,
+					     int write, void __user *buffer,
+					     size_t *length, loff_t *ppos);
+#endif
+
+#endif /* CONFIG_OPTPROBES */
+#ifdef CONFIG_KPROBES_ON_FTRACE
+extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
+				  struct ftrace_ops *ops, struct pt_regs *regs);
+extern int arch_prepare_kprobe_ftrace(struct kprobe *p);
+#endif
+
+int arch_check_ftrace_location(struct kprobe *p);
+
+/* Get the kprobe at this addr (if any) - called with preemption disabled */
+struct kprobe *get_kprobe(void *addr);
+void kretprobe_hash_lock(struct task_struct *tsk,
+			 struct hlist_head **head, unsigned long *flags);
+void kretprobe_hash_unlock(struct task_struct *tsk, unsigned long *flags);
+struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk);
+
+/* kprobe_running() will just return the current_kprobe on this CPU */
+static inline struct kprobe *kprobe_running(void)
+{
+	return (__this_cpu_read(current_kprobe));
+}
+
+static inline void reset_current_kprobe(void)
+{
+	__this_cpu_write(current_kprobe, NULL);
+}
+
+static inline struct kprobe_ctlblk *get_kprobe_ctlblk(void)
+{
+	return this_cpu_ptr(&kprobe_ctlblk);
+}
+
+int register_kprobe(struct kprobe *p);
+void unregister_kprobe(struct kprobe *p);
+int register_kprobes(struct kprobe **kps, int num);
+void unregister_kprobes(struct kprobe **kps, int num);
+int setjmp_pre_handler(struct kprobe *, struct pt_regs *);
+int longjmp_break_handler(struct kprobe *, struct pt_regs *);
+int register_jprobe(struct jprobe *p);
+void unregister_jprobe(struct jprobe *p);
+int register_jprobes(struct jprobe **jps, int num);
+void unregister_jprobes(struct jprobe **jps, int num);
+void jprobe_return(void);
+unsigned long arch_deref_entry_point(void *);
+
+int register_kretprobe(struct kretprobe *rp);
+void unregister_kretprobe(struct kretprobe *rp);
+int register_kretprobes(struct kretprobe **rps, int num);
+void unregister_kretprobes(struct kretprobe **rps, int num);
+
+void kprobe_flush_task(struct task_struct *tk);
+void recycle_rp_inst(struct kretprobe_instance *ri, struct hlist_head *head);
+
+int disable_kprobe(struct kprobe *kp);
+int enable_kprobe(struct kprobe *kp);
+
+void dump_kprobe(struct kprobe *kp);
+
+#else /* !CONFIG_KPROBES: */
+
+static inline int kprobes_built_in(void)
+{
+	return 0;
+}
+static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
+{
+	return 0;
+}
+static inline struct kprobe *get_kprobe(void *addr)
+{
+	return NULL;
+}
+static inline struct kprobe *kprobe_running(void)
+{
+	return NULL;
+}
+static inline int register_kprobe(struct kprobe *p)
+{
+	return -ENOSYS;
+}
+static inline int register_kprobes(struct kprobe **kps, int num)
+{
+	return -ENOSYS;
+}
+static inline void unregister_kprobe(struct kprobe *p)
+{
+}
+static inline void unregister_kprobes(struct kprobe **kps, int num)
+{
+}
+static inline int register_jprobe(struct jprobe *p)
+{
+	return -ENOSYS;
+}
+static inline int register_jprobes(struct jprobe **jps, int num)
+{
+	return -ENOSYS;
+}
+static inline void unregister_jprobe(struct jprobe *p)
+{
+}
+static inline void unregister_jprobes(struct jprobe **jps, int num)
+{
+}
+static inline void jprobe_return(void)
+{
+}
+static inline int register_kretprobe(struct kretprobe *rp)
+{
+	return -ENOSYS;
+}
+static inline int register_kretprobes(struct kretprobe **rps, int num)
+{
+	return -ENOSYS;
+}
+static inline void unregister_kretprobe(struct kretprobe *rp)
+{
+}
+static inline void unregister_kretprobes(struct kretprobe **rps, int num)
+{
+}
+static inline void kprobe_flush_task(struct task_struct *tk)
+{
+}
+static inline int disable_kprobe(struct kprobe *kp)
+{
+	return -ENOSYS;
+}
+static inline int enable_kprobe(struct kprobe *kp)
+{
+	return -ENOSYS;
+}
+#endif /* CONFIG_KPROBES */
+static inline int disable_kretprobe(struct kretprobe *rp)
+{
+	return disable_kprobe(&rp->kp);
+}
+static inline int enable_kretprobe(struct kretprobe *rp)
+{
+	return enable_kprobe(&rp->kp);
+}
+static inline int disable_jprobe(struct jprobe *jp)
+{
+	return disable_kprobe(&jp->kp);
+}
+static inline int enable_jprobe(struct jprobe *jp)
+{
+	return enable_kprobe(&jp->kp);
+}
+
+#ifdef CONFIG_KPROBES
+/*
+ * Blacklist ganerating macro. Specify functions which is not probed
+ * by using this macro.
+ */
+#define __NOKPROBE_SYMBOL(fname)			\
+static unsigned long __used				\
+	__attribute__((section("_kprobe_blacklist")))	\
+	_kbl_addr_##fname = (unsigned long)fname;
+#define NOKPROBE_SYMBOL(fname)	__NOKPROBE_SYMBOL(fname)
+#else
+#define NOKPROBE_SYMBOL(fname)
+#endif
+
+#endif /* _LINUX_KPROBES_H */