diff --git a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c index 99565a66915d..ad469299267a 100644 --- a/arch/i386/kernel/kprobes.c +++ b/arch/i386/kernel/kprobes.c @@ -31,7 +31,6 @@ #include #include #include -#include #include #include #include @@ -123,6 +122,7 @@ static inline void prepare_singlestep(struct kprobe *p, struct pt_regs *regs) regs->eip = (unsigned long)&p->ainsn.insn; } +/* Called with kretprobe_lock held */ void __kprobes arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs) { @@ -168,15 +168,12 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) } /* Check we're not actually recursing */ if (kprobe_running()) { - /* We *are* holding lock here, so this is safe. - Disarm the probe we just hit, and ignore it. */ p = get_kprobe(addr); if (p) { if (kcb->kprobe_status == KPROBE_HIT_SS && *p->ainsn.insn == BREAKPOINT_INSTRUCTION) { regs->eflags &= ~TF_MASK; regs->eflags |= kcb->kprobe_saved_eflags; - unlock_kprobes(); goto no_kprobe; } /* We have reentered the kprobe_handler(), since @@ -197,14 +194,11 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) goto ss_probe; } } - /* If it's not ours, can't be delete race, (we hold lock). */ goto no_kprobe; } - lock_kprobes(); p = get_kprobe(addr); if (!p) { - unlock_kprobes(); if (regs->eflags & VM_MASK) { /* We are in virtual-8086 mode. Return 0 */ goto no_kprobe; @@ -268,9 +262,10 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) struct kretprobe_instance *ri = NULL; struct hlist_head *head; struct hlist_node *node, *tmp; - unsigned long orig_ret_address = 0; + unsigned long flags, orig_ret_address = 0; unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline; + spin_lock_irqsave(&kretprobe_lock, flags); head = kretprobe_inst_table_head(current); /* @@ -310,7 +305,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) regs->eip = orig_ret_address; reset_current_kprobe(); - unlock_kprobes(); + spin_unlock_irqrestore(&kretprobe_lock, flags); preempt_enable_no_resched(); /* @@ -395,7 +390,7 @@ static void __kprobes resume_execution(struct kprobe *p, /* * Interrupts are disabled on entry as trap1 is an interrupt gate and they - * remain disabled thoroughout this function. And we hold kprobe lock. + * remain disabled thoroughout this function. */ static inline int post_kprobe_handler(struct pt_regs *regs) { @@ -419,7 +414,6 @@ static inline int post_kprobe_handler(struct pt_regs *regs) goto out; } reset_current_kprobe(); - unlock_kprobes(); out: preempt_enable_no_resched(); @@ -434,7 +428,6 @@ out: return 1; } -/* Interrupts disabled, kprobe_lock held. */ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) { struct kprobe *cur = kprobe_running(); @@ -448,7 +441,6 @@ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) regs->eflags |= kcb->kprobe_old_eflags; reset_current_kprobe(); - unlock_kprobes(); preempt_enable_no_resched(); } return 0; @@ -463,7 +455,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, struct die_args *args = (struct die_args *)data; int ret = NOTIFY_DONE; - preempt_disable(); + rcu_read_lock(); switch (val) { case DIE_INT3: if (kprobe_handler(args->regs)) @@ -482,7 +474,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, default: break; } - preempt_enable(); + rcu_read_unlock(); return ret; } diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c index 17e70b1b8d79..fddbac32d44a 100644 --- a/arch/ia64/kernel/kprobes.c +++ b/arch/ia64/kernel/kprobes.c @@ -26,7 +26,6 @@ #include #include #include -#include #include #include #include @@ -343,10 +342,11 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) struct kretprobe_instance *ri = NULL; struct hlist_head *head; struct hlist_node *node, *tmp; - unsigned long orig_ret_address = 0; + unsigned long flags, orig_ret_address = 0; unsigned long trampoline_address = ((struct fnptr *)kretprobe_trampoline)->ip; + spin_lock_irqsave(&kretprobe_lock, flags); head = kretprobe_inst_table_head(current); /* @@ -386,7 +386,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) regs->cr_iip = orig_ret_address; reset_current_kprobe(); - unlock_kprobes(); + spin_unlock_irqrestore(&kretprobe_lock, flags); preempt_enable_no_resched(); /* @@ -397,6 +397,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) return 1; } +/* Called with kretprobe_lock held */ void __kprobes arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs) { @@ -612,7 +613,6 @@ static int __kprobes pre_kprobes_handler(struct die_args *args) if ((kcb->kprobe_status == KPROBE_HIT_SS) && (p->ainsn.inst_flag == INST_FLAG_BREAK_INST)) { ia64_psr(regs)->ss = 0; - unlock_kprobes(); goto no_kprobe; } /* We have reentered the pre_kprobe_handler(), since @@ -641,10 +641,8 @@ static int __kprobes pre_kprobes_handler(struct die_args *args) } } - lock_kprobes(); p = get_kprobe(addr); if (!p) { - unlock_kprobes(); if (!is_ia64_break_inst(regs)) { /* * The breakpoint instruction was removed right @@ -707,7 +705,6 @@ static int __kprobes post_kprobes_handler(struct pt_regs *regs) goto out; } reset_current_kprobe(); - unlock_kprobes(); out: preempt_enable_no_resched(); @@ -728,7 +725,6 @@ static int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr) if (kcb->kprobe_status & KPROBE_HIT_SS) { resume_execution(cur, regs); reset_current_kprobe(); - unlock_kprobes(); preempt_enable_no_resched(); } @@ -741,7 +737,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, struct die_args *args = (struct die_args *)data; int ret = NOTIFY_DONE; - preempt_disable(); + rcu_read_lock(); switch(val) { case DIE_BREAK: if (pre_kprobes_handler(args)) @@ -757,7 +753,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, default: break; } - preempt_enable(); + rcu_read_unlock(); return ret; } diff --git a/arch/ppc64/kernel/kprobes.c b/arch/ppc64/kernel/kprobes.c index 3f89f3e5584a..e0a25b35437f 100644 --- a/arch/ppc64/kernel/kprobes.c +++ b/arch/ppc64/kernel/kprobes.c @@ -30,7 +30,6 @@ #include #include #include -#include #include #include #include @@ -125,6 +124,7 @@ static inline void set_current_kprobe(struct kprobe *p, struct pt_regs *regs, kcb->kprobe_saved_msr = regs->msr; } +/* Called with kretprobe_lock held */ void __kprobes arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs) { @@ -152,8 +152,6 @@ static inline int kprobe_handler(struct pt_regs *regs) /* Check we're not actually recursing */ if (kprobe_running()) { - /* We *are* holding lock here, so this is safe. - Disarm the probe we just hit, and ignore it. */ p = get_kprobe(addr); if (p) { kprobe_opcode_t insn = *p->ainsn.insn; @@ -161,7 +159,6 @@ static inline int kprobe_handler(struct pt_regs *regs) is_trap(insn)) { regs->msr &= ~MSR_SE; regs->msr |= kcb->kprobe_saved_msr; - unlock_kprobes(); goto no_kprobe; } /* We have reentered the kprobe_handler(), since @@ -183,14 +180,11 @@ static inline int kprobe_handler(struct pt_regs *regs) goto ss_probe; } } - /* If it's not ours, can't be delete race, (we hold lock). */ goto no_kprobe; } - lock_kprobes(); p = get_kprobe(addr); if (!p) { - unlock_kprobes(); if (*addr != BREAKPOINT_INSTRUCTION) { /* * PowerPC has multiple variants of the "trap" @@ -254,9 +248,10 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) struct kretprobe_instance *ri = NULL; struct hlist_head *head; struct hlist_node *node, *tmp; - unsigned long orig_ret_address = 0; + unsigned long flags, orig_ret_address = 0; unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline; + spin_lock_irqsave(&kretprobe_lock, flags); head = kretprobe_inst_table_head(current); /* @@ -296,7 +291,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) regs->nip = orig_ret_address; reset_current_kprobe(); - unlock_kprobes(); + spin_unlock_irqrestore(&kretprobe_lock, flags); preempt_enable_no_resched(); /* @@ -348,7 +343,6 @@ static inline int post_kprobe_handler(struct pt_regs *regs) goto out; } reset_current_kprobe(); - unlock_kprobes(); out: preempt_enable_no_resched(); @@ -363,7 +357,6 @@ out: return 1; } -/* Interrupts disabled, kprobe_lock held. */ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) { struct kprobe *cur = kprobe_running(); @@ -378,7 +371,6 @@ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) regs->msr |= kcb->kprobe_saved_msr; reset_current_kprobe(); - unlock_kprobes(); preempt_enable_no_resched(); } return 0; @@ -393,11 +385,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, struct die_args *args = (struct die_args *)data; int ret = NOTIFY_DONE; - /* - * Interrupts are not disabled here. We need to disable - * preemption, because kprobe_running() uses smp_processor_id(). - */ - preempt_disable(); + rcu_read_lock(); switch (val) { case DIE_BPT: if (kprobe_handler(args->regs)) @@ -415,7 +403,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, default: break; } - preempt_enable_no_resched(); + rcu_read_unlock(); return ret; } diff --git a/arch/sparc64/kernel/kprobes.c b/arch/sparc64/kernel/kprobes.c index b95984154dba..58a815e90373 100644 --- a/arch/sparc64/kernel/kprobes.c +++ b/arch/sparc64/kernel/kprobes.c @@ -116,15 +116,11 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); if (kprobe_running()) { - /* We *are* holding lock here, so this is safe. - * Disarm the probe we just hit, and ignore it. - */ p = get_kprobe(addr); if (p) { if (kcb->kprobe_status == KPROBE_HIT_SS) { regs->tstate = ((regs->tstate & ~TSTATE_PIL) | kcb->kprobe_orig_tstate_pil); - unlock_kprobes(); goto no_kprobe; } /* We have reentered the kprobe_handler(), since @@ -144,14 +140,11 @@ static int __kprobes kprobe_handler(struct pt_regs *regs) if (p->break_handler && p->break_handler(p, regs)) goto ss_probe; } - /* If it's not ours, can't be delete race, (we hold lock). */ goto no_kprobe; } - lock_kprobes(); p = get_kprobe(addr); if (!p) { - unlock_kprobes(); if (*(u32 *)addr != BREAKPOINT_INSTRUCTION) { /* * The breakpoint instruction was removed right @@ -296,14 +289,12 @@ static inline int post_kprobe_handler(struct pt_regs *regs) goto out; } reset_current_kprobe(); - unlock_kprobes(); out: preempt_enable_no_resched(); return 1; } -/* Interrupts disabled, kprobe_lock held. */ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) { struct kprobe *cur = kprobe_running(); @@ -316,7 +307,6 @@ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) resume_execution(cur, regs, kcb); reset_current_kprobe(); - unlock_kprobes(); preempt_enable_no_resched(); } return 0; @@ -331,7 +321,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, struct die_args *args = (struct die_args *)data; int ret = NOTIFY_DONE; - preempt_disable(); + rcu_read_lock(); switch (val) { case DIE_DEBUG: if (kprobe_handler(args->regs)) @@ -350,7 +340,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, default: break; } - preempt_enable(); + rcu_read_unlock(); return ret; } diff --git a/arch/x86_64/kernel/kprobes.c b/arch/x86_64/kernel/kprobes.c index 6cb40d133b7c..9bef2c8dc12c 100644 --- a/arch/x86_64/kernel/kprobes.c +++ b/arch/x86_64/kernel/kprobes.c @@ -34,7 +34,6 @@ #include #include #include -#include #include #include #include @@ -266,6 +265,7 @@ static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs) regs->rip = (unsigned long)p->ainsn.insn; } +/* Called with kretprobe_lock held */ void __kprobes arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs) { @@ -299,15 +299,12 @@ int __kprobes kprobe_handler(struct pt_regs *regs) /* Check we're not actually recursing */ if (kprobe_running()) { - /* We *are* holding lock here, so this is safe. - Disarm the probe we just hit, and ignore it. */ p = get_kprobe(addr); if (p) { if (kcb->kprobe_status == KPROBE_HIT_SS && *p->ainsn.insn == BREAKPOINT_INSTRUCTION) { regs->eflags &= ~TF_MASK; regs->eflags |= kcb->kprobe_saved_rflags; - unlock_kprobes(); goto no_kprobe; } else if (kcb->kprobe_status == KPROBE_HIT_SSDONE) { /* TODO: Provide re-entrancy from @@ -340,14 +337,11 @@ int __kprobes kprobe_handler(struct pt_regs *regs) goto ss_probe; } } - /* If it's not ours, can't be delete race, (we hold lock). */ goto no_kprobe; } - lock_kprobes(); p = get_kprobe(addr); if (!p) { - unlock_kprobes(); if (*addr != BREAKPOINT_INSTRUCTION) { /* * The breakpoint instruction was removed right @@ -406,9 +400,10 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) struct kretprobe_instance *ri = NULL; struct hlist_head *head; struct hlist_node *node, *tmp; - unsigned long orig_ret_address = 0; + unsigned long flags, orig_ret_address = 0; unsigned long trampoline_address =(unsigned long)&kretprobe_trampoline; + spin_lock_irqsave(&kretprobe_lock, flags); head = kretprobe_inst_table_head(current); /* @@ -448,7 +443,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) regs->rip = orig_ret_address; reset_current_kprobe(); - unlock_kprobes(); + spin_unlock_irqrestore(&kretprobe_lock, flags); preempt_enable_no_resched(); /* @@ -536,10 +531,6 @@ static void __kprobes resume_execution(struct kprobe *p, } } -/* - * Interrupts are disabled on entry as trap1 is an interrupt gate and they - * remain disabled thoroughout this function. And we hold kprobe lock. - */ int __kprobes post_kprobe_handler(struct pt_regs *regs) { struct kprobe *cur = kprobe_running(); @@ -560,8 +551,6 @@ int __kprobes post_kprobe_handler(struct pt_regs *regs) if (kcb->kprobe_status == KPROBE_REENTER) { restore_previous_kprobe(kcb); goto out; - } else { - unlock_kprobes(); } reset_current_kprobe(); out: @@ -578,7 +567,6 @@ out: return 1; } -/* Interrupts disabled, kprobe_lock held. */ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr) { struct kprobe *cur = kprobe_running(); @@ -592,7 +580,6 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr) regs->eflags |= kcb->kprobe_old_rflags; reset_current_kprobe(); - unlock_kprobes(); preempt_enable_no_resched(); } return 0; @@ -607,7 +594,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, struct die_args *args = (struct die_args *)data; int ret = NOTIFY_DONE; - preempt_disable(); + rcu_read_lock(); switch (val) { case DIE_INT3: if (kprobe_handler(args->regs)) @@ -626,7 +613,7 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, default: break; } - preempt_enable(); + rcu_read_unlock(); return ret; }