diff options
Diffstat (limited to 'arch/arm64/kernel/ptrace.c')
| -rw-r--r-- | arch/arm64/kernel/ptrace.c | 173 |
1 files changed, 72 insertions, 101 deletions
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 33a74fc45959..5cafe0e40cfa 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -19,6 +19,7 @@ * along with this program. If not, see <http://www.gnu.org/licenses/>. */ +#include <linux/compat.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/mm.h> @@ -41,6 +42,9 @@ #include <asm/traps.h> #include <asm/system_misc.h> +#define CREATE_TRACE_POINTS +#include <trace/events/syscalls.h> + /* * TODO: does not yet catch signals sent when the child dies. * in exit.c or in signal.c. @@ -53,28 +57,6 @@ 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. @@ -657,28 +639,34 @@ static int compat_gpr_get(struct task_struct *target, for (i = 0; i < num_regs; ++i) { unsigned int idx = start + i; - void *reg; + compat_ulong_t reg; switch (idx) { case 15: - reg = (void *)&task_pt_regs(target)->pc; + reg = task_pt_regs(target)->pc; break; case 16: - reg = (void *)&task_pt_regs(target)->pstate; + reg = task_pt_regs(target)->pstate; break; case 17: - reg = (void *)&task_pt_regs(target)->orig_x0; + reg = task_pt_regs(target)->orig_x0; break; default: - reg = (void *)&task_pt_regs(target)->regs[idx]; + reg = task_pt_regs(target)->regs[idx]; } - ret = copy_to_user(ubuf, reg, sizeof(compat_ulong_t)); + if (kbuf) { + memcpy(kbuf, ®, sizeof(reg)); + kbuf += sizeof(reg); + } else { + ret = copy_to_user(ubuf, ®, sizeof(reg)); + if (ret) { + ret = -EFAULT; + break; + } - if (ret) - break; - else - ubuf += sizeof(compat_ulong_t); + ubuf += sizeof(reg); + } } return ret; @@ -706,28 +694,35 @@ static int compat_gpr_set(struct task_struct *target, for (i = 0; i < num_regs; ++i) { unsigned int idx = start + i; - void *reg; + compat_ulong_t reg; + + if (kbuf) { + memcpy(®, kbuf, sizeof(reg)); + kbuf += sizeof(reg); + } else { + ret = copy_from_user(®, ubuf, sizeof(reg)); + if (ret) { + ret = -EFAULT; + break; + } + + ubuf += sizeof(reg); + } switch (idx) { case 15: - reg = (void *)&newregs.pc; + newregs.pc = reg; break; case 16: - reg = (void *)&newregs.pstate; + newregs.pstate = reg; break; case 17: - reg = (void *)&newregs.orig_x0; + newregs.orig_x0 = reg; break; default: - reg = (void *)&newregs.regs[idx]; + newregs.regs[idx] = reg; } - ret = copy_from_user(reg, ubuf, sizeof(compat_ulong_t)); - - if (ret) - goto out; - else - ubuf += sizeof(compat_ulong_t); } if (valid_user_regs(&newregs.user_regs)) @@ -735,7 +730,6 @@ static int compat_gpr_set(struct task_struct *target, else ret = -EINVAL; -out: return ret; } @@ -816,33 +810,6 @@ 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) { @@ -1114,45 +1081,49 @@ long arch_ptrace(struct task_struct *child, long request, return ptrace_request(child, request, addr, data); } +enum ptrace_syscall_dir { + PTRACE_SYSCALL_ENTER = 0, + PTRACE_SYSCALL_EXIT, +}; -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) +static void tracehook_report_syscall(struct pt_regs *regs, + enum ptrace_syscall_dir dir) { + int regno; unsigned long saved_reg; - if (!test_thread_flag(TIF_SYSCALL_TRACE)) - return regs->syscallno; - - if (is_compat_task()) { - /* AArch32 uses ip (r12) for scratch */ - saved_reg = regs->regs[12]; - regs->regs[12] = dir; - } else { - /* - * Save X7. X7 is used to denote syscall entry/exit: - * X7 = 0 -> entry, = 1 -> exit - */ - saved_reg = regs->regs[7]; - regs->regs[7] = dir; - } + /* + * A scratch register (ip(r12) on AArch32, x7 on AArch64) is + * used to denote syscall entry/exit: + */ + regno = (is_compat_task() ? 12 : 7); + saved_reg = regs->regs[regno]; + regs->regs[regno] = dir; - if (dir) + if (dir == PTRACE_SYSCALL_EXIT) tracehook_report_syscall_exit(regs, 0); else if (tracehook_report_syscall_entry(regs)) regs->syscallno = ~0UL; - if (is_compat_task()) - regs->regs[12] = saved_reg; - else - regs->regs[7] = saved_reg; + regs->regs[regno] = saved_reg; +} + +asmlinkage int syscall_trace_enter(struct pt_regs *regs) +{ + if (test_thread_flag(TIF_SYSCALL_TRACE)) + tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER); + + if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) + trace_sys_enter(regs, regs->syscallno); return regs->syscallno; } + +asmlinkage void syscall_trace_exit(struct pt_regs *regs) +{ + if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) + trace_sys_exit(regs, regs_return_value(regs)); + + if (test_thread_flag(TIF_SYSCALL_TRACE)) + tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT); +} |