diff options
Diffstat (limited to 'arch/arm64/kernel/debug-monitors.c')
| -rw-r--r-- | arch/arm64/kernel/debug-monitors.c | 66 |
1 files changed, 64 insertions, 2 deletions
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) |