diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/kprobes_32.c | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/kprobes_64.c | 1 | ||||
| -rw-r--r-- | arch/x86/mm/fault_32.c | 43 | ||||
| -rw-r--r-- | arch/x86/mm/fault_64.c | 44 |
4 files changed, 39 insertions, 52 deletions
diff --git a/arch/x86/kernel/kprobes_32.c b/arch/x86/kernel/kprobes_32.c index e7d0d3c..06b86e5 100644 --- a/arch/x86/kernel/kprobes_32.c +++ b/arch/x86/kernel/kprobes_32.c @@ -584,7 +584,7 @@ out: return 1; } -static int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr) +int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr) { struct kprobe *cur = kprobe_running(); struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); @@ -666,7 +666,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, ret = NOTIFY_STOP; break; case DIE_GPF: - case DIE_PAGE_FAULT: /* kprobe_running() needs smp_processor_id() */ preempt_disable(); if (kprobe_running() && diff --git a/arch/x86/kernel/kprobes_64.c b/arch/x86/kernel/kprobes_64.c index 62e28e5..7c16506 100644 --- a/arch/x86/kernel/kprobes_64.c +++ b/arch/x86/kernel/kprobes_64.c @@ -657,7 +657,6 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self, ret = NOTIFY_STOP; break; case DIE_GPF: - case DIE_PAGE_FAULT: /* kprobe_running() needs smp_processor_id() */ preempt_disable(); if (kprobe_running() && diff --git a/arch/x86/mm/fault_32.c b/arch/x86/mm/fault_32.c index fcb38e7..be72c2a 100644 --- a/arch/x86/mm/fault_32.c +++ b/arch/x86/mm/fault_32.c @@ -25,6 +25,7 @@ #include <linux/kprobes.h> #include <linux/uaccess.h> #include <linux/kdebug.h> +#include <linux/kprobes.h> #include <asm/system.h> #include <asm/desc.h> @@ -32,33 +33,27 @@ extern void die(const char *,struct pt_regs *,long); -static ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain); - -int register_page_fault_notifier(struct notifier_block *nb) +#ifdef CONFIG_KPROBES +static inline int notify_page_fault(struct pt_regs *regs) { - vmalloc_sync_all(); - return atomic_notifier_chain_register(¬ify_page_fault_chain, nb); -} -EXPORT_SYMBOL_GPL(register_page_fault_notifier); + int ret = 0; + + /* kprobe_running() needs smp_processor_id() */ + if (!user_mode_vm(regs)) { + preempt_disable(); + if (kprobe_running() && kprobe_fault_handler(regs, 14)) + ret = 1; + preempt_enable(); + } -int unregister_page_fault_notifier(struct notifier_block *nb) -{ - return atomic_notifier_chain_unregister(¬ify_page_fault_chain, nb); + return ret; } -EXPORT_SYMBOL_GPL(unregister_page_fault_notifier); - -static inline int notify_page_fault(struct pt_regs *regs, long err) +#else +static inline int notify_page_fault(struct pt_regs *regs) { - struct die_args args = { - .regs = regs, - .str = "page fault", - .err = err, - .trapnr = 14, - .signr = SIGSEGV - }; - return atomic_notifier_call_chain(¬ify_page_fault_chain, - DIE_PAGE_FAULT, &args); + return 0; } +#endif /* * Return EIP plus the CS segment base. The segment limit is also @@ -331,7 +326,7 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs, if (unlikely(address >= TASK_SIZE)) { if (!(error_code & 0x0000000d) && vmalloc_fault(address) >= 0) return; - if (notify_page_fault(regs, error_code) == NOTIFY_STOP) + if (notify_page_fault(regs)) return; /* * Don't take the mm semaphore here. If we fixup a prefetch @@ -340,7 +335,7 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs, goto bad_area_nosemaphore; } - if (notify_page_fault(regs, error_code) == NOTIFY_STOP) + if (notify_page_fault(regs)) return; /* It's safe to allow irq's after cr2 has been saved and the vmalloc diff --git a/arch/x86/mm/fault_64.c b/arch/x86/mm/fault_64.c index 54816ad..5e0e549 100644 --- a/arch/x86/mm/fault_64.c +++ b/arch/x86/mm/fault_64.c @@ -25,6 +25,7 @@ #include <linux/kprobes.h> #include <linux/uaccess.h> #include <linux/kdebug.h> +#include <linux/kprobes.h> #include <asm/system.h> #include <asm/pgalloc.h> @@ -40,34 +41,27 @@ #define PF_RSVD (1<<3) #define PF_INSTR (1<<4) -static ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain); - -/* Hook to register for page fault notifications */ -int register_page_fault_notifier(struct notifier_block *nb) +#ifdef CONFIG_KPROBES +static inline int notify_page_fault(struct pt_regs *regs) { - vmalloc_sync_all(); - return atomic_notifier_chain_register(¬ify_page_fault_chain, nb); -} -EXPORT_SYMBOL_GPL(register_page_fault_notifier); + int ret = 0; + + /* kprobe_running() needs smp_processor_id() */ + if (!user_mode(regs)) { + preempt_disable(); + if (kprobe_running() && kprobe_fault_handler(regs, 14)) + ret = 1; + preempt_enable(); + } -int unregister_page_fault_notifier(struct notifier_block *nb) -{ - return atomic_notifier_chain_unregister(¬ify_page_fault_chain, nb); + return ret; } -EXPORT_SYMBOL_GPL(unregister_page_fault_notifier); - -static inline int notify_page_fault(struct pt_regs *regs, long err) +#else +static inline int notify_page_fault(struct pt_regs *regs) { - struct die_args args = { - .regs = regs, - .str = "page fault", - .err = err, - .trapnr = 14, - .signr = SIGSEGV - }; - return atomic_notifier_call_chain(¬ify_page_fault_chain, - DIE_PAGE_FAULT, &args); + return 0; } +#endif /* Sometimes the CPU reports invalid exceptions on prefetch. Check that here and ignore. @@ -345,7 +339,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, if (vmalloc_fault(address) >= 0) return; } - if (notify_page_fault(regs, error_code) == NOTIFY_STOP) + if (notify_page_fault(regs)) return; /* * Don't take the mm semaphore here. If we fixup a prefetch @@ -354,7 +348,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, goto bad_area_nosemaphore; } - if (notify_page_fault(regs, error_code) == NOTIFY_STOP) + if (notify_page_fault(regs)) return; if (likely(regs->eflags & X86_EFLAGS_IF)) |