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Diffstat (limited to 'arch/arm64/kernel/probes/kprobes.c')
-rw-r--r--arch/arm64/kernel/probes/kprobes.c97
1 files changed, 49 insertions, 48 deletions
diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c
index 70b91a8c6bb3..43a0361a8bf0 100644
--- a/arch/arm64/kernel/probes/kprobes.c
+++ b/arch/arm64/kernel/probes/kprobes.c
@@ -10,6 +10,7 @@
#define pr_fmt(fmt) "kprobes: " fmt
+#include <linux/execmem.h>
#include <linux/extable.h>
#include <linux/kasan.h>
#include <linux/kernel.h>
@@ -27,7 +28,7 @@
#include <asm/debug-monitors.h>
#include <asm/insn.h>
#include <asm/irq.h>
-#include <asm/patching.h>
+#include <asm/text-patching.h>
#include <asm/ptrace.h>
#include <asm/sections.h>
#include <asm/system_misc.h>
@@ -41,9 +42,23 @@ DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
static void __kprobes
post_kprobe_handler(struct kprobe *, struct kprobe_ctlblk *, struct pt_regs *);
+void *alloc_insn_page(void)
+{
+ void *addr;
+
+ addr = execmem_alloc(EXECMEM_KPROBES, PAGE_SIZE);
+ if (!addr)
+ return NULL;
+ if (set_memory_rox((unsigned long)addr, 1)) {
+ execmem_free(addr);
+ return NULL;
+ }
+ return addr;
+}
+
static void __kprobes arch_prepare_ss_slot(struct kprobe *p)
{
- kprobe_opcode_t *addr = p->ainsn.api.insn;
+ kprobe_opcode_t *addr = p->ainsn.xol_insn;
/*
* Prepare insn slot, Mark Rutland points out it depends on a coupe of
@@ -64,20 +79,20 @@ static void __kprobes arch_prepare_ss_slot(struct kprobe *p)
* the BRK exception handler, so it is unnecessary to generate
* Contex-Synchronization-Event via ISB again.
*/
- aarch64_insn_patch_text_nosync(addr, p->opcode);
+ aarch64_insn_patch_text_nosync(addr, le32_to_cpu(p->opcode));
aarch64_insn_patch_text_nosync(addr + 1, BRK64_OPCODE_KPROBES_SS);
/*
* Needs restoring of return address after stepping xol.
*/
- p->ainsn.api.restore = (unsigned long) p->addr +
+ p->ainsn.xol_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.api.restore = 0;
+ p->ainsn.xol_restore = 0;
}
static void __kprobes arch_simulate_insn(struct kprobe *p, struct pt_regs *regs)
@@ -85,7 +100,7 @@ static void __kprobes arch_simulate_insn(struct kprobe *p, struct pt_regs *regs)
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
if (p->ainsn.api.handler)
- p->ainsn.api.handler((u32)p->opcode, (long)p->addr, regs);
+ p->ainsn.api.handler(le32_to_cpu(p->opcode), (long)p->addr, regs);
/* single step simulated, now go for post processing */
post_kprobe_handler(p, kcb, regs);
@@ -99,7 +114,7 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
return -EINVAL;
/* copy instruction */
- p->opcode = le32_to_cpu(*p->addr);
+ p->opcode = *p->addr;
if (search_exception_tables(probe_addr))
return -EINVAL;
@@ -110,18 +125,18 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
return -EINVAL;
case INSN_GOOD_NO_SLOT: /* insn need simulation */
- p->ainsn.api.insn = NULL;
+ p->ainsn.xol_insn = NULL;
break;
case INSN_GOOD: /* instruction uses slot */
- p->ainsn.api.insn = get_insn_slot();
- if (!p->ainsn.api.insn)
+ p->ainsn.xol_insn = get_insn_slot();
+ if (!p->ainsn.xol_insn)
return -ENOMEM;
break;
}
/* prepare the instruction */
- if (p->ainsn.api.insn)
+ if (p->ainsn.xol_insn)
arch_prepare_ss_slot(p);
else
arch_prepare_simulate(p);
@@ -129,13 +144,6 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p)
return 0;
}
-void *alloc_insn_page(void)
-{
- return __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START, VMALLOC_END,
- GFP_KERNEL, PAGE_KERNEL_ROX, VM_FLUSH_RESET_PERMS,
- NUMA_NO_NODE, __builtin_return_address(0));
-}
-
/* arm kprobe: install breakpoint in text */
void __kprobes arch_arm_kprobe(struct kprobe *p)
{
@@ -149,15 +157,16 @@ void __kprobes arch_arm_kprobe(struct kprobe *p)
void __kprobes arch_disarm_kprobe(struct kprobe *p)
{
void *addr = p->addr;
+ u32 insn = le32_to_cpu(p->opcode);
- aarch64_insn_patch_text(&addr, &p->opcode, 1);
+ aarch64_insn_patch_text(&addr, &insn, 1);
}
void __kprobes arch_remove_kprobe(struct kprobe *p)
{
- if (p->ainsn.api.insn) {
- free_insn_slot(p->ainsn.api.insn, 0);
- p->ainsn.api.insn = NULL;
+ if (p->ainsn.xol_insn) {
+ free_insn_slot(p->ainsn.xol_insn, 0);
+ p->ainsn.xol_insn = NULL;
}
}
@@ -212,9 +221,9 @@ static void __kprobes setup_singlestep(struct kprobe *p,
}
- if (p->ainsn.api.insn) {
+ if (p->ainsn.xol_insn) {
/* prepare for single stepping */
- slot = (unsigned long)p->ainsn.api.insn;
+ slot = (unsigned long)p->ainsn.xol_insn;
kprobes_save_local_irqflag(kcb, regs);
instruction_pointer_set(regs, slot);
@@ -252,8 +261,8 @@ static void __kprobes
post_kprobe_handler(struct kprobe *cur, struct kprobe_ctlblk *kcb, struct pt_regs *regs)
{
/* return addr restore if non-branching insn */
- if (cur->ainsn.api.restore != 0)
- instruction_pointer_set(regs, cur->ainsn.api.restore);
+ if (cur->ainsn.xol_restore != 0)
+ instruction_pointer_set(regs, cur->ainsn.xol_restore);
/* restore back original saved kprobe variables and continue */
if (kcb->kprobe_status == KPROBE_REENTER) {
@@ -298,8 +307,8 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr)
return 0;
}
-static int __kprobes
-kprobe_breakpoint_handler(struct pt_regs *regs, unsigned long esr)
+int __kprobes
+kprobe_brk_handler(struct pt_regs *regs, unsigned long esr)
{
struct kprobe *p, *cur_kprobe;
struct kprobe_ctlblk *kcb;
@@ -342,20 +351,15 @@ kprobe_breakpoint_handler(struct pt_regs *regs, unsigned long esr)
return DBG_HOOK_HANDLED;
}
-static struct break_hook kprobes_break_hook = {
- .imm = KPROBES_BRK_IMM,
- .fn = kprobe_breakpoint_handler,
-};
-
-static int __kprobes
-kprobe_breakpoint_ss_handler(struct pt_regs *regs, unsigned long esr)
+int __kprobes
+kprobe_ss_brk_handler(struct pt_regs *regs, unsigned long esr)
{
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
unsigned long addr = instruction_pointer(regs);
struct kprobe *cur = kprobe_running();
if (cur && (kcb->kprobe_status & (KPROBE_HIT_SS | KPROBE_REENTER)) &&
- ((unsigned long)&cur->ainsn.api.insn[1] == addr)) {
+ ((unsigned long)&cur->ainsn.xol_insn[1] == addr)) {
kprobes_restore_local_irqflag(kcb, regs);
post_kprobe_handler(cur, kcb, regs);
@@ -366,10 +370,15 @@ kprobe_breakpoint_ss_handler(struct pt_regs *regs, unsigned long esr)
return DBG_HOOK_ERROR;
}
-static struct break_hook kprobes_break_ss_hook = {
- .imm = KPROBES_BRK_SS_IMM,
- .fn = kprobe_breakpoint_ss_handler,
-};
+int __kprobes
+kretprobe_brk_handler(struct pt_regs *regs, unsigned long esr)
+{
+ if (regs->pc != (unsigned long)__kretprobe_trampoline)
+ return DBG_HOOK_ERROR;
+
+ regs->pc = kretprobe_trampoline_handler(regs, (void *)regs->regs[29]);
+ return DBG_HOOK_HANDLED;
+}
/*
* Provide a blacklist of symbols identifying ranges which cannot be kprobed.
@@ -396,11 +405,6 @@ int __init arch_populate_kprobe_blacklist(void)
return ret;
}
-void __kprobes __used *trampoline_probe_handler(struct pt_regs *regs)
-{
- return (void *)kretprobe_trampoline_handler(regs, (void *)regs->regs[29]);
-}
-
void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
struct pt_regs *regs)
{
@@ -418,8 +422,5 @@ int __kprobes arch_trampoline_kprobe(struct kprobe *p)
int __init arch_init_kprobes(void)
{
- register_kernel_break_hook(&kprobes_break_hook);
- register_kernel_break_hook(&kprobes_break_ss_hook);
-
return 0;
}