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Diffstat (limited to 'arch/arm64/kernel/debug-monitors.c')
-rw-r--r--arch/arm64/kernel/debug-monitors.c66
1 files changed, 64 insertions, 2 deletions
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index f4726dc054b..08018e3df58 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)