From mboxrd@z Thu Jan 1 00:00:00 1970 From: panand@redhat.com (Pratyush Anand) Date: Tue, 2 Aug 2016 11:00:05 +0530 Subject: [PATCH 1/5] arm64: kprobe: protect/rename few definitions to be reused by uprobe In-Reply-To: References: Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org decode-insn code has to be reused by arm64 uprobe implementation as well. Therefore, this patch protects some portion of kprobe code and renames few other, so that decode-insn functionality can be reused by uprobe even when CONFIG_KPROBES is not defined. kprobe_opcode_t and struct arch_specific_insn are also defined by linux/kprobes.h, when CONFIG_KPROBES is not defined. So, protect these definitions in asm/probes.h. linux/kprobes.h already includes asm/kprobes.h. Therefore, remove inclusion of asm/kprobes.h from decode-insn.c. There are some definitions like kprobe_insn and kprobes_handler_t etc can be re-used by uprobe. So, it would be better to remove 'k' from their names. struct arch_specific_insn is specific to kprobe. Therefore, introduce a new struct arch_probe_insn which will be common for both kprobe and uprobe, so that decode-insn code can be shared. Modify kprobe code accordingly. Function arm_probe_decode_insn() will be needed by uprobe as well. So make it global. Signed-off-by: Pratyush Anand --- arch/arm64/include/asm/probes.h | 19 ++++++++++-------- arch/arm64/kernel/probes/decode-insn.c | 31 +++++++++++++++-------------- arch/arm64/kernel/probes/decode-insn.h | 8 ++++++-- arch/arm64/kernel/probes/kprobes.c | 36 +++++++++++++++++----------------- 4 files changed, 51 insertions(+), 43 deletions(-) diff --git a/arch/arm64/include/asm/probes.h b/arch/arm64/include/asm/probes.h index 5af574d632fa..e175a825b187 100644 --- a/arch/arm64/include/asm/probes.h +++ b/arch/arm64/include/asm/probes.h @@ -17,19 +17,22 @@ #include -struct kprobe; -struct arch_specific_insn; - -typedef u32 kprobe_opcode_t; -typedef void (kprobes_handler_t) (u32 opcode, long addr, struct pt_regs *); +typedef u32 probe_opcode_t; +typedef void (probes_handler_t) (u32 opcode, long addr, struct pt_regs *); /* architecture specific copy of original instruction */ -struct arch_specific_insn { - kprobe_opcode_t *insn; +struct arch_probe_insn { + probe_opcode_t *insn; pstate_check_t *pstate_cc; - kprobes_handler_t *handler; + probes_handler_t *handler; /* restore address after step xol */ unsigned long restore; }; +#ifdef CONFIG_KPROBES +typedef u32 kprobe_opcode_t; +struct arch_specific_insn { + struct arch_probe_insn api; +}; +#endif #endif diff --git a/arch/arm64/kernel/probes/decode-insn.c b/arch/arm64/kernel/probes/decode-insn.c index 37e47a9d617e..335984cd3a99 100644 --- a/arch/arm64/kernel/probes/decode-insn.c +++ b/arch/arm64/kernel/probes/decode-insn.c @@ -16,7 +16,6 @@ #include #include #include -#include #include #include @@ -77,8 +76,8 @@ static bool __kprobes aarch64_insn_is_steppable(u32 insn) * INSN_GOOD If instruction is supported and uses instruction slot, * INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot. */ -static enum kprobe_insn __kprobes -arm_probe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi) +enum probe_insn __kprobes +arm_probe_decode_insn(probe_opcode_t insn, struct arch_probe_insn *api) { /* * Instructions reading or modifying the PC won't work from the XOL @@ -88,26 +87,26 @@ arm_probe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi) return INSN_GOOD; if (aarch64_insn_is_bcond(insn)) { - asi->handler = simulate_b_cond; + api->handler = simulate_b_cond; } else if (aarch64_insn_is_cbz(insn) || aarch64_insn_is_cbnz(insn)) { - asi->handler = simulate_cbz_cbnz; + api->handler = simulate_cbz_cbnz; } else if (aarch64_insn_is_tbz(insn) || aarch64_insn_is_tbnz(insn)) { - asi->handler = simulate_tbz_tbnz; + api->handler = simulate_tbz_tbnz; } else if (aarch64_insn_is_adr_adrp(insn)) { - asi->handler = simulate_adr_adrp; + api->handler = simulate_adr_adrp; } else if (aarch64_insn_is_b(insn) || aarch64_insn_is_bl(insn)) { - asi->handler = simulate_b_bl; + api->handler = simulate_b_bl; } else if (aarch64_insn_is_br(insn) || aarch64_insn_is_blr(insn) || aarch64_insn_is_ret(insn)) { - asi->handler = simulate_br_blr_ret; + api->handler = simulate_br_blr_ret; } else if (aarch64_insn_is_ldr_lit(insn)) { - asi->handler = simulate_ldr_literal; + api->handler = simulate_ldr_literal; } else if (aarch64_insn_is_ldrsw_lit(insn)) { - asi->handler = simulate_ldrsw_literal; + api->handler = simulate_ldrsw_literal; } else { /* * Instruction cannot be stepped out-of-line and we don't @@ -119,6 +118,7 @@ arm_probe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi) return INSN_GOOD_NO_SLOT; } +#ifdef CONFIG_KPROBES static bool __kprobes is_probed_address_atomic(kprobe_opcode_t *scan_start, kprobe_opcode_t *scan_end) { @@ -137,11 +137,11 @@ is_probed_address_atomic(kprobe_opcode_t *scan_start, kprobe_opcode_t *scan_end) return false; } -enum kprobe_insn __kprobes +enum probe_insn __kprobes arm_kprobe_decode_insn(kprobe_opcode_t *addr, struct arch_specific_insn *asi) { - enum kprobe_insn decoded; - kprobe_opcode_t insn = le32_to_cpu(*addr); + enum probe_insn decoded; + probe_opcode_t insn = le32_to_cpu(*addr); kprobe_opcode_t *scan_start = addr - 1; kprobe_opcode_t *scan_end = addr - MAX_ATOMIC_CONTEXT_SIZE; #if defined(CONFIG_MODULES) && defined(MODULES_VADDR) @@ -164,7 +164,7 @@ arm_kprobe_decode_insn(kprobe_opcode_t *addr, struct arch_specific_insn *asi) preempt_enable(); } #endif - decoded = arm_probe_decode_insn(insn, asi); + decoded = arm_probe_decode_insn(insn, &asi->api); if (decoded == INSN_REJECTED || is_probed_address_atomic(scan_start, scan_end)) @@ -172,3 +172,4 @@ arm_kprobe_decode_insn(kprobe_opcode_t *addr, struct arch_specific_insn *asi) return decoded; } +#endif diff --git a/arch/arm64/kernel/probes/decode-insn.h b/arch/arm64/kernel/probes/decode-insn.h index d438289646a6..76d3f315407f 100644 --- a/arch/arm64/kernel/probes/decode-insn.h +++ b/arch/arm64/kernel/probes/decode-insn.h @@ -23,13 +23,17 @@ */ #define MAX_ATOMIC_CONTEXT_SIZE (128 / sizeof(kprobe_opcode_t)) -enum kprobe_insn { +enum probe_insn { INSN_REJECTED, INSN_GOOD_NO_SLOT, INSN_GOOD, }; -enum kprobe_insn __kprobes +#ifdef CONFIG_KPROBES +enum probe_insn __kprobes arm_kprobe_decode_insn(kprobe_opcode_t *addr, struct arch_specific_insn *asi); +#endif +enum probe_insn __kprobes +arm_probe_decode_insn(probe_opcode_t insn, struct arch_probe_insn *asi); #endif /* _ARM_KERNEL_KPROBES_ARM64_H */ diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index bf9768588288..8e5923c04fef 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -56,31 +56,31 @@ static inline unsigned long min_stack_size(unsigned long addr) static void __kprobes arch_prepare_ss_slot(struct kprobe *p) { /* prepare insn slot */ - p->ainsn.insn[0] = cpu_to_le32(p->opcode); + p->ainsn.api.insn[0] = cpu_to_le32(p->opcode); - flush_icache_range((uintptr_t) (p->ainsn.insn), - (uintptr_t) (p->ainsn.insn) + + flush_icache_range((uintptr_t) (p->ainsn.api.insn), + (uintptr_t) (p->ainsn.api.insn) + MAX_INSN_SIZE * sizeof(kprobe_opcode_t)); /* * Needs restoring of return address after stepping xol. */ - p->ainsn.restore = (unsigned long) p->addr + + p->ainsn.api.restore = (unsigned long) p->addr + sizeof(kprobe_opcode_t); } static void __kprobes arch_prepare_simulate(struct kprobe *p) { /* This instructions is not executed xol. No need to adjust the PC */ - p->ainsn.restore = 0; + p->ainsn.api.restore = 0; } static void __kprobes arch_simulate_insn(struct kprobe *p, struct pt_regs *regs) { struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - if (p->ainsn.handler) - p->ainsn.handler((u32)p->opcode, (long)p->addr, regs); + if (p->ainsn.api.handler) + p->ainsn.api.handler((u32)p->opcode, (long)p->addr, regs); /* single step simulated, now go for post processing */ post_kprobe_handler(kcb, regs); @@ -110,18 +110,18 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) return -EINVAL; case INSN_GOOD_NO_SLOT: /* insn need simulation */ - p->ainsn.insn = NULL; + p->ainsn.api.insn = NULL; break; case INSN_GOOD: /* instruction uses slot */ - p->ainsn.insn = get_insn_slot(); - if (!p->ainsn.insn) + p->ainsn.api.insn = get_insn_slot(); + if (!p->ainsn.api.insn) return -ENOMEM; break; }; /* prepare the instruction */ - if (p->ainsn.insn) + if (p->ainsn.api.insn) arch_prepare_ss_slot(p); else arch_prepare_simulate(p); @@ -154,9 +154,9 @@ void __kprobes arch_disarm_kprobe(struct kprobe *p) void __kprobes arch_remove_kprobe(struct kprobe *p) { - if (p->ainsn.insn) { - free_insn_slot(p->ainsn.insn, 0); - p->ainsn.insn = NULL; + if (p->ainsn.api.insn) { + free_insn_slot(p->ainsn.api.insn, 0); + p->ainsn.api.insn = NULL; } } @@ -251,9 +251,9 @@ static void __kprobes setup_singlestep(struct kprobe *p, } - if (p->ainsn.insn) { + if (p->ainsn.api.insn) { /* prepare for single stepping */ - slot = (unsigned long)p->ainsn.insn; + slot = (unsigned long)p->ainsn.api.insn; set_ss_context(kcb, slot); /* mark pending ss */ @@ -305,8 +305,8 @@ post_kprobe_handler(struct kprobe_ctlblk *kcb, struct pt_regs *regs) return; /* return addr restore if non-branching insn */ - if (cur->ainsn.restore != 0) - instruction_pointer_set(regs, cur->ainsn.restore); + if (cur->ainsn.api.restore != 0) + instruction_pointer_set(regs, cur->ainsn.api.restore); /* restore back original saved kprobe variables and continue */ if (kcb->kprobe_status == KPROBE_REENTER) { -- 2.5.5