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-rw-r--r--arch/arm64/include/asm/debug-monitors.h9
-rw-r--r--arch/arm64/include/asm/ptrace.h2
-rw-r--r--arch/arm64/kernel/debug-monitors.c66
-rw-r--r--arch/arm64/kernel/ptrace.c59
-rw-r--r--arch/arm64/kernel/traps.c5
5 files changed, 75 insertions, 66 deletions
diff --git a/arch/arm64/include/asm/debug-monitors.h b/arch/arm64/include/asm/debug-monitors.h
index 7eaa0b302493..ef8235c68c09 100644
--- a/arch/arm64/include/asm/debug-monitors.h
+++ b/arch/arm64/include/asm/debug-monitors.h
@@ -83,6 +83,15 @@ static inline int reinstall_suspended_bps(struct pt_regs *regs)
}
#endif
+#ifdef CONFIG_COMPAT
+int aarch32_break_handler(struct pt_regs *regs);
+#else
+static int aarch32_break_handler(struct pt_regs *regs)
+{
+ return -EFAULT;
+}
+#endif
+
#endif /* __ASSEMBLY */
#endif /* __KERNEL__ */
#endif /* __ASM_DEBUG_MONITORS_H */
diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index 41a71ee4c3df..0dacbbf9458b 100644
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h
@@ -171,7 +171,5 @@ extern unsigned long profile_pc(struct pt_regs *regs);
#define profile_pc(regs) instruction_pointer(regs)
#endif
-extern int aarch32_break_trap(struct pt_regs *regs);
-
#endif /* __ASSEMBLY__ */
#endif
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index f4726dc054b3..08018e3df580 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -24,6 +24,7 @@
#include <linux/init.h>
#include <linux/ptrace.h>
#include <linux/stat.h>
+#include <linux/uaccess.h>
#include <asm/debug-monitors.h>
#include <asm/local.h>
@@ -226,13 +227,74 @@ static int single_step_handler(unsigned long addr, unsigned int esr,
return 0;
}
-static int __init single_step_init(void)
+static int brk_handler(unsigned long addr, unsigned int esr,
+ struct pt_regs *regs)
+{
+ siginfo_t info;
+
+ if (!user_mode(regs))
+ return -EFAULT;
+
+ info = (siginfo_t) {
+ .si_signo = SIGTRAP,
+ .si_errno = 0,
+ .si_code = TRAP_BRKPT,
+ .si_addr = (void __user *)instruction_pointer(regs),
+ };
+
+ force_sig_info(SIGTRAP, &info, current);
+ return 0;
+}
+
+int aarch32_break_handler(struct pt_regs *regs)
+{
+ siginfo_t info;
+ unsigned int instr;
+ bool bp = false;
+ void __user *pc = (void __user *)instruction_pointer(regs);
+
+ if (!compat_user_mode(regs))
+ return -EFAULT;
+
+ if (compat_thumb_mode(regs)) {
+ /* get 16-bit Thumb instruction */
+ get_user(instr, (u16 __user *)pc);
+ if (instr == AARCH32_BREAK_THUMB2_LO) {
+ /* get second half of 32-bit Thumb-2 instruction */
+ get_user(instr, (u16 __user *)(pc + 2));
+ bp = instr == AARCH32_BREAK_THUMB2_HI;
+ } else {
+ bp = instr == AARCH32_BREAK_THUMB;
+ }
+ } else {
+ /* 32-bit ARM instruction */
+ get_user(instr, (u32 __user *)pc);
+ bp = (instr & ~0xf0000000) == AARCH32_BREAK_ARM;
+ }
+
+ if (!bp)
+ return -EFAULT;
+
+ info = (siginfo_t) {
+ .si_signo = SIGTRAP,
+ .si_errno = 0,
+ .si_code = TRAP_BRKPT,
+ .si_addr = pc,
+ };
+
+ force_sig_info(SIGTRAP, &info, current);
+ return 0;
+}
+
+static int __init debug_traps_init(void)
{
hook_debug_fault_code(DBG_ESR_EVT_HWSS, single_step_handler, SIGTRAP,
TRAP_HWBKPT, "single-step handler");
+ hook_debug_fault_code(DBG_ESR_EVT_BRK, brk_handler, SIGTRAP,
+ TRAP_BRKPT, "ptrace BRK handler");
return 0;
}
-arch_initcall(single_step_init);
+arch_initcall(debug_traps_init);
/* Re-enable single step for syscall restarting. */
void user_rewind_single_step(struct task_struct *task)
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 6e1e77f1831c..fecdbf7de82e 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -53,28 +53,6 @@ void ptrace_disable(struct task_struct *child)
{
}
-/*
- * Handle hitting a breakpoint.
- */
-static int ptrace_break(struct pt_regs *regs)
-{
- siginfo_t info = {
- .si_signo = SIGTRAP,
- .si_errno = 0,
- .si_code = TRAP_BRKPT,
- .si_addr = (void __user *)instruction_pointer(regs),
- };
-
- force_sig_info(SIGTRAP, &info, current);
- return 0;
-}
-
-static int arm64_break_trap(unsigned long addr, unsigned int esr,
- struct pt_regs *regs)
-{
- return ptrace_break(regs);
-}
-
#ifdef CONFIG_HAVE_HW_BREAKPOINT
/*
* Handle hitting a HW-breakpoint.
@@ -817,33 +795,6 @@ static const struct user_regset_view user_aarch32_view = {
.regsets = aarch32_regsets, .n = ARRAY_SIZE(aarch32_regsets)
};
-int aarch32_break_trap(struct pt_regs *regs)
-{
- unsigned int instr;
- bool bp = false;
- void __user *pc = (void __user *)instruction_pointer(regs);
-
- if (compat_thumb_mode(regs)) {
- /* get 16-bit Thumb instruction */
- get_user(instr, (u16 __user *)pc);
- if (instr == AARCH32_BREAK_THUMB2_LO) {
- /* get second half of 32-bit Thumb-2 instruction */
- get_user(instr, (u16 __user *)(pc + 2));
- bp = instr == AARCH32_BREAK_THUMB2_HI;
- } else {
- bp = instr == AARCH32_BREAK_THUMB;
- }
- } else {
- /* 32-bit ARM instruction */
- get_user(instr, (u32 __user *)pc);
- bp = (instr & ~0xf0000000) == AARCH32_BREAK_ARM;
- }
-
- if (bp)
- return ptrace_break(regs);
- return 1;
-}
-
static int compat_ptrace_read_user(struct task_struct *tsk, compat_ulong_t off,
compat_ulong_t __user *ret)
{
@@ -1111,16 +1062,6 @@ long arch_ptrace(struct task_struct *child, long request,
return ptrace_request(child, request, addr, data);
}
-
-static int __init ptrace_break_init(void)
-{
- hook_debug_fault_code(DBG_ESR_EVT_BRK, arm64_break_trap, SIGTRAP,
- TRAP_BRKPT, "ptrace BRK handler");
- return 0;
-}
-core_initcall(ptrace_break_init);
-
-
asmlinkage int syscall_trace(int dir, struct pt_regs *regs)
{
unsigned long saved_reg;
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index f30852d28590..7ffadddb645d 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -32,6 +32,7 @@
#include <linux/syscalls.h>
#include <asm/atomic.h>
+#include <asm/debug-monitors.h>
#include <asm/traps.h>
#include <asm/stacktrace.h>
#include <asm/exception.h>
@@ -261,11 +262,9 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
siginfo_t info;
void __user *pc = (void __user *)instruction_pointer(regs);
-#ifdef CONFIG_COMPAT
/* check for AArch32 breakpoint instructions */
- if (compat_user_mode(regs) && aarch32_break_trap(regs) == 0)
+ if (!aarch32_break_handler(regs))
return;
-#endif
if (show_unhandled_signals && unhandled_signal(current, SIGILL) &&
printk_ratelimit()) {
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