From 4a296e07c3a410c09b9155da4c2fa84a07964f38 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Mon, 28 Apr 2008 02:14:29 -0700 Subject: [PATCH] kprobes: add (un)register_kretprobes for batch registration Introduce unregister_/register_kretprobes() for kretprobe batch registration. Signed-off-by: Masami Hiramatsu Cc: Ananth N Mavinakayanahalli Cc: Jim Keniston Cc: Prasanna S Panchamukhi Cc: Shaohua Li Cc: David Miller Cc: "Frank Ch. Eigler" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/kprobes.h | 9 ++++ kernel/kprobes.c | 108 ++++++++++++++++++++++++++++++++-------- 2 files changed, 97 insertions(+), 20 deletions(-) diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index 2ba7df645a84..94c855a236ae 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -245,6 +245,8 @@ 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); @@ -287,9 +289,16 @@ 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) { } diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 76275fc025a5..5e3144ad9b64 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -429,6 +429,21 @@ static inline void free_rp_inst(struct kretprobe *rp) } } +static void __kprobes cleanup_rp_inst(struct kretprobe *rp) +{ + unsigned long flags; + struct kretprobe_instance *ri; + struct hlist_node *pos, *next; + /* No race here */ + spin_lock_irqsave(&kretprobe_lock, flags); + hlist_for_each_entry_safe(ri, pos, next, &rp->used_instances, uflist) { + ri->rp = NULL; + hlist_del(&ri->uflist); + } + spin_unlock_irqrestore(&kretprobe_lock, flags); + free_rp_inst(rp); +} + /* * Keep all fields in the kprobe consistent */ @@ -798,7 +813,8 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p, return 0; } -int __kprobes register_kretprobe(struct kretprobe *rp) +static int __kprobes __register_kretprobe(struct kretprobe *rp, + unsigned long called_from) { int ret = 0; struct kretprobe_instance *inst; @@ -844,43 +860,93 @@ int __kprobes register_kretprobe(struct kretprobe *rp) rp->nmissed = 0; /* Establish function entry probe point */ - if ((ret = __register_kprobe(&rp->kp, - (unsigned long)__builtin_return_address(0))) != 0) + ret = __register_kprobe(&rp->kp, called_from); + if (ret != 0) free_rp_inst(rp); return ret; } +static int __register_kretprobes(struct kretprobe **rps, int num, + unsigned long called_from) +{ + int ret = 0, i; + + if (num <= 0) + return -EINVAL; + for (i = 0; i < num; i++) { + ret = __register_kretprobe(rps[i], called_from); + if (ret < 0 && i > 0) { + unregister_kretprobes(rps, i); + break; + } + } + return ret; +} + +int __kprobes register_kretprobe(struct kretprobe *rp) +{ + return __register_kretprobes(&rp, 1, + (unsigned long)__builtin_return_address(0)); +} + +void __kprobes unregister_kretprobe(struct kretprobe *rp) +{ + unregister_kretprobes(&rp, 1); +} + +int __kprobes register_kretprobes(struct kretprobe **rps, int num) +{ + return __register_kretprobes(rps, num, + (unsigned long)__builtin_return_address(0)); +} + +void __kprobes unregister_kretprobes(struct kretprobe **rps, int num) +{ + int i; + + if (num <= 0) + return; + mutex_lock(&kprobe_mutex); + for (i = 0; i < num; i++) + if (__unregister_kprobe_top(&rps[i]->kp) < 0) + rps[i]->kp.addr = NULL; + mutex_unlock(&kprobe_mutex); + + synchronize_sched(); + for (i = 0; i < num; i++) { + if (rps[i]->kp.addr) { + __unregister_kprobe_bottom(&rps[i]->kp); + cleanup_rp_inst(rps[i]); + } + } +} + #else /* CONFIG_KRETPROBES */ int __kprobes register_kretprobe(struct kretprobe *rp) { return -ENOSYS; } -static int __kprobes pre_handler_kretprobe(struct kprobe *p, - struct pt_regs *regs) +int __kprobes register_kretprobes(struct kretprobe **rps, int num) { - return 0; + return -ENOSYS; } -#endif /* CONFIG_KRETPROBES */ - void __kprobes unregister_kretprobe(struct kretprobe *rp) { - unsigned long flags; - struct kretprobe_instance *ri; - struct hlist_node *pos, *next; +} - unregister_kprobe(&rp->kp); +void __kprobes unregister_kretprobes(struct kretprobe **rps, int num) +{ +} - /* No race here */ - spin_lock_irqsave(&kretprobe_lock, flags); - hlist_for_each_entry_safe(ri, pos, next, &rp->used_instances, uflist) { - ri->rp = NULL; - hlist_del(&ri->uflist); - } - spin_unlock_irqrestore(&kretprobe_lock, flags); - free_rp_inst(rp); +static int __kprobes pre_handler_kretprobe(struct kprobe *p, + struct pt_regs *regs) +{ + return 0; } +#endif /* CONFIG_KRETPROBES */ + static int __init init_kprobes(void) { int i, err = 0; @@ -1177,4 +1243,6 @@ EXPORT_SYMBOL_GPL(jprobe_return); #ifdef CONFIG_KPROBES EXPORT_SYMBOL_GPL(register_kretprobe); EXPORT_SYMBOL_GPL(unregister_kretprobe); +EXPORT_SYMBOL_GPL(register_kretprobes); +EXPORT_SYMBOL_GPL(unregister_kretprobes); #endif -- 2.20.1