From bb144a85c70a65730424ad1a9dc50fef66e5cafe Mon Sep 17 00:00:00 2001 From: Prasanna S Panchamukhi Date: Tue, 6 Sep 2005 15:19:29 -0700 Subject: [PATCH] [PATCH] Kprobes: prevent possible race conditions ppc64 changes This patch contains the ppc64 architecture specific changes to prevent the possible race conditions. Signed-off-by: Prasanna S Panchamukhi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ppc64/kernel/kprobes.c | 29 +++++++++++++++-------------- arch/ppc64/kernel/misc.S | 4 ++-- arch/ppc64/kernel/traps.c | 5 +++-- arch/ppc64/kernel/vmlinux.lds.S | 1 + arch/ppc64/mm/fault.c | 5 +++-- include/asm-ppc64/processor.h | 14 ++++++++++++++ 6 files changed, 38 insertions(+), 20 deletions(-) diff --git a/arch/ppc64/kernel/kprobes.c b/arch/ppc64/kernel/kprobes.c index a3d519518fb8..591e4b67b5a5 100644 --- a/arch/ppc64/kernel/kprobes.c +++ b/arch/ppc64/kernel/kprobes.c @@ -44,7 +44,7 @@ static struct kprobe *kprobe_prev; static unsigned long kprobe_status_prev, kprobe_saved_msr_prev; static struct pt_regs jprobe_saved_regs; -int arch_prepare_kprobe(struct kprobe *p) +int __kprobes arch_prepare_kprobe(struct kprobe *p) { int ret = 0; kprobe_opcode_t insn = *p->addr; @@ -68,27 +68,27 @@ int arch_prepare_kprobe(struct kprobe *p) return ret; } -void arch_copy_kprobe(struct kprobe *p) +void __kprobes arch_copy_kprobe(struct kprobe *p) { memcpy(p->ainsn.insn, p->addr, MAX_INSN_SIZE * sizeof(kprobe_opcode_t)); p->opcode = *p->addr; } -void arch_arm_kprobe(struct kprobe *p) +void __kprobes arch_arm_kprobe(struct kprobe *p) { *p->addr = BREAKPOINT_INSTRUCTION; flush_icache_range((unsigned long) p->addr, (unsigned long) p->addr + sizeof(kprobe_opcode_t)); } -void arch_disarm_kprobe(struct kprobe *p) +void __kprobes arch_disarm_kprobe(struct kprobe *p) { *p->addr = p->opcode; flush_icache_range((unsigned long) p->addr, (unsigned long) p->addr + sizeof(kprobe_opcode_t)); } -void arch_remove_kprobe(struct kprobe *p) +void __kprobes arch_remove_kprobe(struct kprobe *p) { up(&kprobe_mutex); free_insn_slot(p->ainsn.insn); @@ -122,7 +122,8 @@ static inline void restore_previous_kprobe(void) kprobe_saved_msr = kprobe_saved_msr_prev; } -void arch_prepare_kretprobe(struct kretprobe *rp, struct pt_regs *regs) +void __kprobes arch_prepare_kretprobe(struct kretprobe *rp, + struct pt_regs *regs) { struct kretprobe_instance *ri; @@ -244,7 +245,7 @@ void kretprobe_trampoline_holder(void) /* * Called when the probe at kretprobe trampoline is hit */ -int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) +int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) { struct kretprobe_instance *ri = NULL; struct hlist_head *head; @@ -308,7 +309,7 @@ int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs) * single-stepped a copy of the instruction. The address of this * copy is p->ainsn.insn. */ -static void resume_execution(struct kprobe *p, struct pt_regs *regs) +static void __kprobes resume_execution(struct kprobe *p, struct pt_regs *regs) { int ret; unsigned int insn = *p->ainsn.insn; @@ -373,8 +374,8 @@ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr) /* * Wrapper routine to for handling exceptions. */ -int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, - void *data) +int __kprobes kprobe_exceptions_notify(struct notifier_block *self, + unsigned long val, void *data) { struct die_args *args = (struct die_args *)data; int ret = NOTIFY_DONE; @@ -406,7 +407,7 @@ int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, return ret; } -int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) +int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) { struct jprobe *jp = container_of(p, struct jprobe, kp); @@ -419,16 +420,16 @@ int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs) return 1; } -void jprobe_return(void) +void __kprobes jprobe_return(void) { asm volatile("trap" ::: "memory"); } -void jprobe_return_end(void) +void __kprobes jprobe_return_end(void) { }; -int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) +int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs) { /* * FIXME - we should ideally be validating that we got here 'cos diff --git a/arch/ppc64/kernel/misc.S b/arch/ppc64/kernel/misc.S index 2164bd7b4ef6..6d860c1d9fa0 100644 --- a/arch/ppc64/kernel/misc.S +++ b/arch/ppc64/kernel/misc.S @@ -183,7 +183,7 @@ PPC64_CACHES: * flush all bytes from start through stop-1 inclusive */ -_GLOBAL(__flush_icache_range) +_KPROBE(__flush_icache_range) /* * Flush the data cache to memory @@ -223,7 +223,7 @@ _GLOBAL(__flush_icache_range) bdnz 2b isync blr - + .previous .text /* * Like above, but only do the D-cache. * diff --git a/arch/ppc64/kernel/traps.c b/arch/ppc64/kernel/traps.c index a8d5e83ee89f..7467ae508e6e 100644 --- a/arch/ppc64/kernel/traps.c +++ b/arch/ppc64/kernel/traps.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include @@ -220,7 +221,7 @@ void instruction_breakpoint_exception(struct pt_regs *regs) _exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip); } -void single_step_exception(struct pt_regs *regs) +void __kprobes single_step_exception(struct pt_regs *regs) { regs->msr &= ~MSR_SE; /* Turn off 'trace' bit */ @@ -398,7 +399,7 @@ check_bug_trap(struct pt_regs *regs) return 0; } -void program_check_exception(struct pt_regs *regs) +void __kprobes program_check_exception(struct pt_regs *regs) { if (debugger_fault_handler(regs)) return; diff --git a/arch/ppc64/kernel/vmlinux.lds.S b/arch/ppc64/kernel/vmlinux.lds.S index 4103cc13f8d6..0306510bc4ff 100644 --- a/arch/ppc64/kernel/vmlinux.lds.S +++ b/arch/ppc64/kernel/vmlinux.lds.S @@ -15,6 +15,7 @@ SECTIONS *(.text .text.*) SCHED_TEXT LOCK_TEXT + KPROBES_TEXT *(.fixup) . = ALIGN(4096); _etext = .; diff --git a/arch/ppc64/mm/fault.c b/arch/ppc64/mm/fault.c index 20b0f37e8bf8..772f0714a5b7 100644 --- a/arch/ppc64/mm/fault.c +++ b/arch/ppc64/mm/fault.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include @@ -84,8 +85,8 @@ static int store_updates_sp(struct pt_regs *regs) * The return value is 0 if the fault was handled, or the signal * number if this is a kernel fault that can't be handled here. */ -int do_page_fault(struct pt_regs *regs, unsigned long address, - unsigned long error_code) +int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address, + unsigned long error_code) { struct vm_area_struct * vma; struct mm_struct *mm = current->mm; diff --git a/include/asm-ppc64/processor.h b/include/asm-ppc64/processor.h index 7bd4796f1236..8bd7aa959385 100644 --- a/include/asm-ppc64/processor.h +++ b/include/asm-ppc64/processor.h @@ -311,6 +311,20 @@ name: \ .type GLUE(.,name),@function; \ GLUE(.,name): +#define _KPROBE(name) \ + .section ".kprobes.text","a"; \ + .align 2 ; \ + .globl name; \ + .globl GLUE(.,name); \ + .section ".opd","aw"; \ +name: \ + .quad GLUE(.,name); \ + .quad .TOC.@tocbase; \ + .quad 0; \ + .previous; \ + .type GLUE(.,name),@function; \ +GLUE(.,name): + #define _STATIC(name) \ .section ".text"; \ .align 2 ; \ -- 2.20.1