diff options
Diffstat (limited to 'arch/arm64/kernel')
-rw-r--r-- | arch/arm64/kernel/debug-monitors.c | 66 | ||||
-rw-r--r-- | arch/arm64/kernel/ptrace.c | 59 | ||||
-rw-r--r-- | arch/arm64/kernel/traps.c | 5 |
3 files changed, 66 insertions, 64 deletions
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c index f4726dc..08018e3 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 6e1e77f..fecdbf7 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 f30852d..7ffaddd 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()) { |