diff options
| -rw-r--r-- | include/linux/kprobes.h | 28 | ||||
| -rw-r--r-- | kernel/kprobes.c | 69 |
2 files changed, 22 insertions, 75 deletions
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index d304d45..b7a194c 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -104,33 +104,12 @@ struct jprobe { }; #ifdef ARCH_SUPPORTS_KRETPROBES -extern int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs); -extern void trampoline_post_handler(struct kprobe *p, struct pt_regs *regs, - unsigned long flags); -extern struct task_struct *arch_get_kprobe_task(void *ptr); extern void arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs); -extern void arch_kprobe_flush_task(struct task_struct *tk); #else /* ARCH_SUPPORTS_KRETPROBES */ -static inline void kretprobe_trampoline(void) -{ -} -static inline int trampoline_probe_handler(struct kprobe *p, - struct pt_regs *regs) -{ - return 0; -} -static inline void trampoline_post_handler(struct kprobe *p, - struct pt_regs *regs, unsigned long flags) -{ -} static inline void arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs) { } -static inline void arch_kprobe_flush_task(struct task_struct *tk) -{ -} -#define arch_get_kprobe_task(ptr) ((struct task_struct *)NULL) #endif /* ARCH_SUPPORTS_KRETPROBES */ /* * Function-return probe - @@ -155,8 +134,8 @@ struct kretprobe_instance { struct hlist_node uflist; /* either on free list or used list */ struct hlist_node hlist; struct kretprobe *rp; - void *ret_addr; - void *stack_addr; + kprobe_opcode_t *ret_addr; + struct task_struct *task; }; #ifdef CONFIG_KPROBES @@ -176,6 +155,7 @@ extern void arch_copy_kprobe(struct kprobe *p); extern void arch_arm_kprobe(struct kprobe *p); extern void arch_disarm_kprobe(struct kprobe *p); extern void arch_remove_kprobe(struct kprobe *p); +extern int arch_init(void); extern void show_registers(struct pt_regs *regs); extern kprobe_opcode_t *get_insn_slot(void); extern void free_insn_slot(kprobe_opcode_t *slot); @@ -196,8 +176,6 @@ int register_kretprobe(struct kretprobe *rp); void unregister_kretprobe(struct kretprobe *rp); struct kretprobe_instance *get_free_rp_inst(struct kretprobe *rp); -struct kretprobe_instance *get_rp_inst(void *sara); -struct kretprobe_instance *get_rp_inst_tsk(struct task_struct *tk); void add_rp_inst(struct kretprobe_instance *ri); void kprobe_flush_task(struct task_struct *tk); void recycle_rp_inst(struct kretprobe_instance *ri); diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 6524252..90c0e82 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -240,12 +240,6 @@ static int aggr_break_handler(struct kprobe *p, struct pt_regs *regs) return 0; } -struct kprobe trampoline_p = { - .addr = (kprobe_opcode_t *) &kretprobe_trampoline, - .pre_handler = trampoline_probe_handler, - .post_handler = trampoline_post_handler -}; - struct kretprobe_instance *get_free_rp_inst(struct kretprobe *rp) { struct hlist_node *node; @@ -264,35 +258,18 @@ static struct kretprobe_instance *get_used_rp_inst(struct kretprobe *rp) return NULL; } -struct kretprobe_instance *get_rp_inst(void *sara) -{ - struct hlist_head *head; - struct hlist_node *node; - struct task_struct *tsk; - struct kretprobe_instance *ri; - - tsk = arch_get_kprobe_task(sara); - head = &kretprobe_inst_table[hash_ptr(tsk, KPROBE_HASH_BITS)]; - hlist_for_each_entry(ri, node, head, hlist) { - if (ri->stack_addr == sara) - return ri; - } - return NULL; -} - void add_rp_inst(struct kretprobe_instance *ri) { - struct task_struct *tsk; /* * Remove rp inst off the free list - * Add it back when probed function returns */ hlist_del(&ri->uflist); - tsk = arch_get_kprobe_task(ri->stack_addr); + /* Add rp inst onto table */ INIT_HLIST_NODE(&ri->hlist); hlist_add_head(&ri->hlist, - &kretprobe_inst_table[hash_ptr(tsk, KPROBE_HASH_BITS)]); + &kretprobe_inst_table[hash_ptr(ri->task, KPROBE_HASH_BITS)]); /* Also add this rp inst to the used list. */ INIT_HLIST_NODE(&ri->uflist); @@ -319,34 +296,25 @@ struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk) return &kretprobe_inst_table[hash_ptr(tsk, KPROBE_HASH_BITS)]; } -struct kretprobe_instance *get_rp_inst_tsk(struct task_struct *tk) -{ - struct task_struct *tsk; - struct hlist_head *head; - struct hlist_node *node; - struct kretprobe_instance *ri; - - head = &kretprobe_inst_table[hash_ptr(tk, KPROBE_HASH_BITS)]; - - hlist_for_each_entry(ri, node, head, hlist) { - tsk = arch_get_kprobe_task(ri->stack_addr); - if (tsk == tk) - return ri; - } - return NULL; -} - /* - * This function is called from do_exit or do_execv when task tk's stack is - * about to be recycled. Recycle any function-return probe instances - * associated with this task. These represent probed functions that have - * been called but may never return. + * This function is called from exit_thread or flush_thread when task tk's + * stack is being recycled so that we can recycle any function-return probe + * instances associated with this task. These left over instances represent + * probed functions that have been called but will never return. */ void kprobe_flush_task(struct task_struct *tk) { + struct kretprobe_instance *ri; + struct hlist_head *head; + struct hlist_node *node, *tmp; unsigned long flags = 0; + spin_lock_irqsave(&kprobe_lock, flags); - arch_kprobe_flush_task(tk); + head = kretprobe_inst_table_head(current); + hlist_for_each_entry_safe(ri, node, tmp, head, hlist) { + if (ri->task == tk) + recycle_rp_inst(ri); + } spin_unlock_irqrestore(&kprobe_lock, flags); } @@ -606,9 +574,10 @@ static int __init init_kprobes(void) INIT_HLIST_HEAD(&kretprobe_inst_table[i]); } - err = register_die_notifier(&kprobe_exceptions_nb); - /* Register the trampoline probe for return probe */ - register_kprobe(&trampoline_p); + err = arch_init(); + if (!err) + err = register_die_notifier(&kprobe_exceptions_nb); + return err; } |