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-rw-r--r--arch/arm/include/asm/hw_breakpoint.h7
-rw-r--r--arch/arm/include/asm/kprobes.h2
-rw-r--r--arch/arm/include/asm/probes.h1
-rw-r--r--arch/arm/kernel/hw_breakpoint.c78
-rw-r--r--arch/arm/probes/kprobes/core.c139
-rw-r--r--arch/arm/probes/kprobes/test-core.c1
6 files changed, 51 insertions, 177 deletions
diff --git a/arch/arm/include/asm/hw_breakpoint.h b/arch/arm/include/asm/hw_breakpoint.h
index e46e4e7bdba3..ac54c06764e6 100644
--- a/arch/arm/include/asm/hw_breakpoint.h
+++ b/arch/arm/include/asm/hw_breakpoint.h
@@ -111,14 +111,17 @@ static inline void decode_ctrl_reg(u32 reg,
asm volatile("mcr p14, 0, %0, " #N "," #M ", " #OP2 : : "r" (VAL));\
} while (0)
+struct perf_event_attr;
struct notifier_block;
struct perf_event;
struct pmu;
extern int arch_bp_generic_fields(struct arch_hw_breakpoint_ctrl ctrl,
int *gen_len, int *gen_type);
-extern int arch_check_bp_in_kernelspace(struct perf_event *bp);
-extern int arch_validate_hwbkpt_settings(struct perf_event *bp);
+extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
+extern int hw_breakpoint_arch_parse(struct perf_event *bp,
+ const struct perf_event_attr *attr,
+ struct arch_hw_breakpoint *hw);
extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
unsigned long val, void *data);
diff --git a/arch/arm/include/asm/kprobes.h b/arch/arm/include/asm/kprobes.h
index 59655459da59..82290f212d8e 100644
--- a/arch/arm/include/asm/kprobes.h
+++ b/arch/arm/include/asm/kprobes.h
@@ -44,8 +44,6 @@ struct prev_kprobe {
struct kprobe_ctlblk {
unsigned int kprobe_status;
struct prev_kprobe prev_kprobe;
- struct pt_regs jprobe_saved_regs;
- char jprobes_stack[MAX_STACK_SIZE];
};
void arch_remove_kprobe(struct kprobe *);
diff --git a/arch/arm/include/asm/probes.h b/arch/arm/include/asm/probes.h
index 1e5b9bb92270..991c9127c650 100644
--- a/arch/arm/include/asm/probes.h
+++ b/arch/arm/include/asm/probes.h
@@ -51,7 +51,6 @@ struct arch_probes_insn {
* We assume one instruction can consume at most 64 bytes stack, which is
* 'push {r0-r15}'. Instructions consume more or unknown stack space like
* 'str r0, [sp, #-80]' and 'str r0, [sp, r1]' should be prohibit to probe.
- * Both kprobe and jprobe use this macro.
*/
#define MAX_STACK_SIZE 64
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index 629e25152c0d..1d5fbf1d1c67 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -456,14 +456,13 @@ static int get_hbp_len(u8 hbp_len)
/*
* Check whether bp virtual address is in kernel space.
*/
-int arch_check_bp_in_kernelspace(struct perf_event *bp)
+int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
{
unsigned int len;
unsigned long va;
- struct arch_hw_breakpoint *info = counter_arch_bp(bp);
- va = info->address;
- len = get_hbp_len(info->ctrl.len);
+ va = hw->address;
+ len = get_hbp_len(hw->ctrl.len);
return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE);
}
@@ -518,42 +517,42 @@ int arch_bp_generic_fields(struct arch_hw_breakpoint_ctrl ctrl,
/*
* Construct an arch_hw_breakpoint from a perf_event.
*/
-static int arch_build_bp_info(struct perf_event *bp)
+static int arch_build_bp_info(struct perf_event *bp,
+ const struct perf_event_attr *attr,
+ struct arch_hw_breakpoint *hw)
{
- struct arch_hw_breakpoint *info = counter_arch_bp(bp);
-
/* Type */
- switch (bp->attr.bp_type) {
+ switch (attr->bp_type) {
case HW_BREAKPOINT_X:
- info->ctrl.type = ARM_BREAKPOINT_EXECUTE;
+ hw->ctrl.type = ARM_BREAKPOINT_EXECUTE;
break;
case HW_BREAKPOINT_R:
- info->ctrl.type = ARM_BREAKPOINT_LOAD;
+ hw->ctrl.type = ARM_BREAKPOINT_LOAD;
break;
case HW_BREAKPOINT_W:
- info->ctrl.type = ARM_BREAKPOINT_STORE;
+ hw->ctrl.type = ARM_BREAKPOINT_STORE;
break;
case HW_BREAKPOINT_RW:
- info->ctrl.type = ARM_BREAKPOINT_LOAD | ARM_BREAKPOINT_STORE;
+ hw->ctrl.type = ARM_BREAKPOINT_LOAD | ARM_BREAKPOINT_STORE;
break;
default:
return -EINVAL;
}
/* Len */
- switch (bp->attr.bp_len) {
+ switch (attr->bp_len) {
case HW_BREAKPOINT_LEN_1:
- info->ctrl.len = ARM_BREAKPOINT_LEN_1;
+ hw->ctrl.len = ARM_BREAKPOINT_LEN_1;
break;
case HW_BREAKPOINT_LEN_2:
- info->ctrl.len = ARM_BREAKPOINT_LEN_2;
+ hw->ctrl.len = ARM_BREAKPOINT_LEN_2;
break;
case HW_BREAKPOINT_LEN_4:
- info->ctrl.len = ARM_BREAKPOINT_LEN_4;
+ hw->ctrl.len = ARM_BREAKPOINT_LEN_4;
break;
case HW_BREAKPOINT_LEN_8:
- info->ctrl.len = ARM_BREAKPOINT_LEN_8;
- if ((info->ctrl.type != ARM_BREAKPOINT_EXECUTE)
+ hw->ctrl.len = ARM_BREAKPOINT_LEN_8;
+ if ((hw->ctrl.type != ARM_BREAKPOINT_EXECUTE)
&& max_watchpoint_len >= 8)
break;
default:
@@ -566,24 +565,24 @@ static int arch_build_bp_info(struct perf_event *bp)
* by the hardware and must be aligned to the appropriate number of
* bytes.
*/
- if (info->ctrl.type == ARM_BREAKPOINT_EXECUTE &&
- info->ctrl.len != ARM_BREAKPOINT_LEN_2 &&
- info->ctrl.len != ARM_BREAKPOINT_LEN_4)
+ if (hw->ctrl.type == ARM_BREAKPOINT_EXECUTE &&
+ hw->ctrl.len != ARM_BREAKPOINT_LEN_2 &&
+ hw->ctrl.len != ARM_BREAKPOINT_LEN_4)
return -EINVAL;
/* Address */
- info->address = bp->attr.bp_addr;
+ hw->address = attr->bp_addr;
/* Privilege */
- info->ctrl.privilege = ARM_BREAKPOINT_USER;
- if (arch_check_bp_in_kernelspace(bp))
- info->ctrl.privilege |= ARM_BREAKPOINT_PRIV;
+ hw->ctrl.privilege = ARM_BREAKPOINT_USER;
+ if (arch_check_bp_in_kernelspace(hw))
+ hw->ctrl.privilege |= ARM_BREAKPOINT_PRIV;
/* Enabled? */
- info->ctrl.enabled = !bp->attr.disabled;
+ hw->ctrl.enabled = !attr->disabled;
/* Mismatch */
- info->ctrl.mismatch = 0;
+ hw->ctrl.mismatch = 0;
return 0;
}
@@ -591,9 +590,10 @@ static int arch_build_bp_info(struct perf_event *bp)
/*
* Validate the arch-specific HW Breakpoint register settings.
*/
-int arch_validate_hwbkpt_settings(struct perf_event *bp)
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+ const struct perf_event_attr *attr,
+ struct arch_hw_breakpoint *hw)
{
- struct arch_hw_breakpoint *info = counter_arch_bp(bp);
int ret = 0;
u32 offset, alignment_mask = 0x3;
@@ -602,14 +602,14 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
return -ENODEV;
/* Build the arch_hw_breakpoint. */
- ret = arch_build_bp_info(bp);
+ ret = arch_build_bp_info(bp, attr, hw);
if (ret)
goto out;
/* Check address alignment. */
- if (info->ctrl.len == ARM_BREAKPOINT_LEN_8)
+ if (hw->ctrl.len == ARM_BREAKPOINT_LEN_8)
alignment_mask = 0x7;
- offset = info->address & alignment_mask;
+ offset = hw->address & alignment_mask;
switch (offset) {
case 0:
/* Aligned */
@@ -617,19 +617,19 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
case 1:
case 2:
/* Allow halfword watchpoints and breakpoints. */
- if (info->ctrl.len == ARM_BREAKPOINT_LEN_2)
+ if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2)
break;
case 3:
/* Allow single byte watchpoint. */
- if (info->ctrl.len == ARM_BREAKPOINT_LEN_1)
+ if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1)
break;
default:
ret = -EINVAL;
goto out;
}
- info->address &= ~alignment_mask;
- info->ctrl.len <<= offset;
+ hw->address &= ~alignment_mask;
+ hw->ctrl.len <<= offset;
if (is_default_overflow_handler(bp)) {
/*
@@ -640,7 +640,7 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
return -EINVAL;
/* We don't allow mismatch breakpoints in kernel space. */
- if (arch_check_bp_in_kernelspace(bp))
+ if (arch_check_bp_in_kernelspace(hw))
return -EPERM;
/*
@@ -655,8 +655,8 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
* reports them.
*/
if (!debug_exception_updates_fsr() &&
- (info->ctrl.type == ARM_BREAKPOINT_LOAD ||
- info->ctrl.type == ARM_BREAKPOINT_STORE))
+ (hw->ctrl.type == ARM_BREAKPOINT_LOAD ||
+ hw->ctrl.type == ARM_BREAKPOINT_STORE))
return -EINVAL;
}
diff --git a/arch/arm/probes/kprobes/core.c b/arch/arm/probes/kprobes/core.c
index e90cc8a08186..f8bd523d64d1 100644
--- a/arch/arm/probes/kprobes/core.c
+++ b/arch/arm/probes/kprobes/core.c
@@ -47,9 +47,6 @@
(unsigned long)(addr) + \
(size))
-/* Used as a marker in ARM_pc to note when we're in a jprobe. */
-#define JPROBE_MAGIC_ADDR 0xffffffff
-
DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
@@ -289,8 +286,8 @@ void __kprobes kprobe_handler(struct pt_regs *regs)
break;
case KPROBE_REENTER:
/* A nested probe was hit in FIQ, it is a BUG */
- pr_warn("Unrecoverable kprobe detected at %p.\n",
- p->addr);
+ pr_warn("Unrecoverable kprobe detected.\n");
+ dump_kprobe(p);
/* fall through */
default:
/* impossible cases */
@@ -303,10 +300,10 @@ void __kprobes kprobe_handler(struct pt_regs *regs)
/*
* If we have no pre-handler or it returned 0, we
- * continue with normal processing. If we have a
- * pre-handler and it returned non-zero, it prepped
- * for calling the break_handler below on re-entry,
- * so get out doing nothing more here.
+ * continue with normal processing. If we have a
+ * pre-handler and it returned non-zero, it will
+ * modify the execution path and no need to single
+ * stepping. Let's just reset current kprobe and exit.
*/
if (!p->pre_handler || !p->pre_handler(p, regs)) {
kcb->kprobe_status = KPROBE_HIT_SS;
@@ -315,20 +312,9 @@ void __kprobes kprobe_handler(struct pt_regs *regs)
kcb->kprobe_status = KPROBE_HIT_SSDONE;
p->post_handler(p, regs, 0);
}
- reset_current_kprobe();
- }
- }
- } else if (cur) {
- /* We probably hit a jprobe. Call its break handler. */
- if (cur->break_handler && cur->break_handler(cur, regs)) {
- kcb->kprobe_status = KPROBE_HIT_SS;
- singlestep(cur, regs, kcb);
- if (cur->post_handler) {
- kcb->kprobe_status = KPROBE_HIT_SSDONE;
- cur->post_handler(cur, regs, 0);
}
+ reset_current_kprobe();
}
- reset_current_kprobe();
} else {
/*
* The probe was removed and a race is in progress.
@@ -521,117 +507,6 @@ void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
regs->ARM_lr = (unsigned long)&kretprobe_trampoline;
}
-int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
-{
- struct jprobe *jp = container_of(p, struct jprobe, kp);
- struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
- long sp_addr = regs->ARM_sp;
- long cpsr;
-
- kcb->jprobe_saved_regs = *regs;
- memcpy(kcb->jprobes_stack, (void *)sp_addr, MIN_STACK_SIZE(sp_addr));
- regs->ARM_pc = (long)jp->entry;
-
- cpsr = regs->ARM_cpsr | PSR_I_BIT;
-#ifdef CONFIG_THUMB2_KERNEL
- /* Set correct Thumb state in cpsr */
- if (regs->ARM_pc & 1)
- cpsr |= PSR_T_BIT;
- else
- cpsr &= ~PSR_T_BIT;
-#endif
- regs->ARM_cpsr = cpsr;
-
- preempt_disable();
- return 1;
-}
-
-void __kprobes jprobe_return(void)
-{
- struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
-
- __asm__ __volatile__ (
- /*
- * Setup an empty pt_regs. Fill SP and PC fields as
- * they're needed by longjmp_break_handler.
- *
- * We allocate some slack between the original SP and start of
- * our fabricated regs. To be precise we want to have worst case
- * covered which is STMFD with all 16 regs so we allocate 2 *
- * sizeof(struct_pt_regs)).
- *
- * This is to prevent any simulated instruction from writing
- * over the regs when they are accessing the stack.
- */
-#ifdef CONFIG_THUMB2_KERNEL
- "sub r0, %0, %1 \n\t"
- "mov sp, r0 \n\t"
-#else
- "sub sp, %0, %1 \n\t"
-#endif
- "ldr r0, ="__stringify(JPROBE_MAGIC_ADDR)"\n\t"
- "str %0, [sp, %2] \n\t"
- "str r0, [sp, %3] \n\t"
- "mov r0, sp \n\t"
- "bl kprobe_handler \n\t"
-
- /*
- * Return to the context saved by setjmp_pre_handler
- * and restored by longjmp_break_handler.
- */
-#ifdef CONFIG_THUMB2_KERNEL
- "ldr lr, [sp, %2] \n\t" /* lr = saved sp */
- "ldrd r0, r1, [sp, %5] \n\t" /* r0,r1 = saved lr,pc */
- "ldr r2, [sp, %4] \n\t" /* r2 = saved psr */
- "stmdb lr!, {r0, r1, r2} \n\t" /* push saved lr and */
- /* rfe context */
- "ldmia sp, {r0 - r12} \n\t"
- "mov sp, lr \n\t"
- "ldr lr, [sp], #4 \n\t"
- "rfeia sp! \n\t"
-#else
- "ldr r0, [sp, %4] \n\t"
- "msr cpsr_cxsf, r0 \n\t"
- "ldmia sp, {r0 - pc} \n\t"
-#endif
- :
- : "r" (kcb->jprobe_saved_regs.ARM_sp),
- "I" (sizeof(struct pt_regs) * 2),
- "J" (offsetof(struct pt_regs, ARM_sp)),
- "J" (offsetof(struct pt_regs, ARM_pc)),
- "J" (offsetof(struct pt_regs, ARM_cpsr)),
- "J" (offsetof(struct pt_regs, ARM_lr))
- : "memory", "cc");
-}
-
-int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
-{
- struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
- long stack_addr = kcb->jprobe_saved_regs.ARM_sp;
- long orig_sp = regs->ARM_sp;
- struct jprobe *jp = container_of(p, struct jprobe, kp);
-
- if (regs->ARM_pc == JPROBE_MAGIC_ADDR) {
- if (orig_sp != stack_addr) {
- struct pt_regs *saved_regs =
- (struct pt_regs *)kcb->jprobe_saved_regs.ARM_sp;
- printk("current sp %lx does not match saved sp %lx\n",
- orig_sp, stack_addr);
- printk("Saved registers for jprobe %p\n", jp);
- show_regs(saved_regs);
- printk("Current registers\n");
- show_regs(regs);
- BUG();
- }
- *regs = kcb->jprobe_saved_regs;
- memcpy((void *)stack_addr, kcb->jprobes_stack,
- MIN_STACK_SIZE(stack_addr));
- preempt_enable_no_resched();
- return 1;
- }
- return 0;
-}
-
int __kprobes arch_trampoline_kprobe(struct kprobe *p)
{
return 0;
diff --git a/arch/arm/probes/kprobes/test-core.c b/arch/arm/probes/kprobes/test-core.c
index 14db14152909..cc237fa9b90f 100644
--- a/arch/arm/probes/kprobes/test-core.c
+++ b/arch/arm/probes/kprobes/test-core.c
@@ -1461,7 +1461,6 @@ fail:
print_registers(&result_regs);
if (mem) {
- pr_err("current_stack=%p\n", current_stack);
pr_err("expected_memory:\n");
print_memory(expected_memory, mem_size);
pr_err("result_memory:\n");
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-30 13:49:35 +0000