From d0b2f91bede3bd5e3d24dd6803e56eee959c1797 Mon Sep 17 00:00:00 2001 From: AndrĂ© Fabian Silva Delgado Date: Thu, 20 Oct 2016 00:10:27 -0300 Subject: Linux-libre 4.8.2-gnu --- arch/arm64/kernel/traps.c | 162 +++++++++++++++++++++++++++++++++++----------- 1 file changed, 125 insertions(+), 37 deletions(-) (limited to 'arch/arm64/kernel/traps.c') diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 2a4301261..df0675084 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -41,6 +41,7 @@ #include #include #include +#include static const char *handler[]= { "Synchronous Abort", @@ -52,15 +53,14 @@ static const char *handler[]= { int show_unhandled_signals = 1; /* - * Dump out the contents of some memory nicely... + * Dump out the contents of some kernel memory nicely... */ static void dump_mem(const char *lvl, const char *str, unsigned long bottom, - unsigned long top, bool compat) + unsigned long top) { unsigned long first; mm_segment_t fs; int i; - unsigned int width = compat ? 4 : 8; /* * We need to switch to kernel mode so that we can use __get_user @@ -78,22 +78,15 @@ static void dump_mem(const char *lvl, const char *str, unsigned long bottom, memset(str, ' ', sizeof(str)); str[sizeof(str) - 1] = '\0'; - for (p = first, i = 0; i < (32 / width) - && p < top; i++, p += width) { + for (p = first, i = 0; i < (32 / 8) + && p < top; i++, p += 8) { if (p >= bottom && p < top) { unsigned long val; - if (width == 8) { - if (__get_user(val, (unsigned long *)p) == 0) - sprintf(str + i * 17, " %016lx", val); - else - sprintf(str + i * 17, " ????????????????"); - } else { - if (__get_user(val, (unsigned int *)p) == 0) - sprintf(str + i * 9, " %08lx", val); - else - sprintf(str + i * 9, " ????????"); - } + if (__get_user(val, (unsigned long *)p) == 0) + sprintf(str + i * 17, " %016lx", val); + else + sprintf(str + i * 17, " ????????????????"); } } printk("%s%04lx:%s\n", lvl, first & 0xffff, str); @@ -149,6 +142,11 @@ static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) unsigned long irq_stack_ptr; int skip; + pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk); + + if (!tsk) + tsk = current; + /* * Switching between stacks is valid when tracing current and in * non-preemptible context. @@ -158,11 +156,6 @@ static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) else irq_stack_ptr = 0; - pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk); - - if (!tsk) - tsk = current; - if (tsk == current) { frame.fp = (unsigned long)__builtin_frame_address(0); frame.sp = current_stack_pointer; @@ -216,7 +209,7 @@ static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk) stack = IRQ_STACK_TO_TASK_STACK(irq_stack_ptr); dump_mem("", "Exception stack", stack, - stack + sizeof(struct pt_regs), false); + stack + sizeof(struct pt_regs)); } } } @@ -254,10 +247,9 @@ static int __die(const char *str, int err, struct thread_info *thread, pr_emerg("Process %.*s (pid: %d, stack limit = 0x%p)\n", TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1); - if (!user_mode(regs) || in_interrupt()) { + if (!user_mode(regs)) { dump_mem(KERN_EMERG, "Stack: ", regs->sp, - THREAD_SIZE + (unsigned long)task_stack_page(tsk), - compat_user_mode(regs)); + THREAD_SIZE + (unsigned long)task_stack_page(tsk)); dump_backtrace(regs, tsk); dump_instr(KERN_EMERG, regs); } @@ -373,11 +365,59 @@ exit: return fn ? fn(regs, instr) : 1; } -asmlinkage void __exception do_undefinstr(struct pt_regs *regs) +static void force_signal_inject(int signal, int code, struct pt_regs *regs, + unsigned long address) { siginfo_t info; void __user *pc = (void __user *)instruction_pointer(regs); + const char *desc; + + switch (signal) { + case SIGILL: + desc = "undefined instruction"; + break; + case SIGSEGV: + desc = "illegal memory access"; + break; + default: + desc = "bad mode"; + break; + } + + if (unhandled_signal(current, signal) && + show_unhandled_signals_ratelimited()) { + pr_info("%s[%d]: %s: pc=%p\n", + current->comm, task_pid_nr(current), desc, pc); + dump_instr(KERN_INFO, regs); + } + + info.si_signo = signal; + info.si_errno = 0; + info.si_code = code; + info.si_addr = pc; + + arm64_notify_die(desc, regs, &info, 0); +} + +/* + * Set up process info to signal segmentation fault - called on access error. + */ +void arm64_notify_segfault(struct pt_regs *regs, unsigned long addr) +{ + int code; + down_read(¤t->mm->mmap_sem); + if (find_vma(current->mm, addr) == NULL) + code = SEGV_MAPERR; + else + code = SEGV_ACCERR; + up_read(¤t->mm->mmap_sem); + + force_signal_inject(SIGSEGV, code, regs, addr); +} + +asmlinkage void __exception do_undefinstr(struct pt_regs *regs) +{ /* check for AArch32 breakpoint instructions */ if (!aarch32_break_handler(regs)) return; @@ -385,18 +425,66 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs) if (call_undef_hook(regs) == 0) return; - if (unhandled_signal(current, SIGILL) && show_unhandled_signals_ratelimited()) { - pr_info("%s[%d]: undefined instruction: pc=%p\n", - current->comm, task_pid_nr(current), pc); - dump_instr(KERN_INFO, regs); - } + force_signal_inject(SIGILL, ILL_ILLOPC, regs, 0); +} - info.si_signo = SIGILL; - info.si_errno = 0; - info.si_code = ILL_ILLOPC; - info.si_addr = pc; +void cpu_enable_cache_maint_trap(void *__unused) +{ + config_sctlr_el1(SCTLR_EL1_UCI, 0); +} - arm64_notify_die("Oops - undefined instruction", regs, &info, 0); +#define __user_cache_maint(insn, address, res) \ + asm volatile ( \ + "1: " insn ", %1\n" \ + " mov %w0, #0\n" \ + "2:\n" \ + " .pushsection .fixup,\"ax\"\n" \ + " .align 2\n" \ + "3: mov %w0, %w2\n" \ + " b 2b\n" \ + " .popsection\n" \ + _ASM_EXTABLE(1b, 3b) \ + : "=r" (res) \ + : "r" (address), "i" (-EFAULT) ) + +asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs) +{ + unsigned long address; + int ret; + + /* if this is a write with: Op0=1, Op2=1, Op1=3, CRn=7 */ + if ((esr & 0x01fffc01) == 0x0012dc00) { + int rt = (esr >> 5) & 0x1f; + int crm = (esr >> 1) & 0x0f; + + address = (rt == 31) ? 0 : regs->regs[rt]; + + switch (crm) { + case 11: /* DC CVAU, gets promoted */ + __user_cache_maint("dc civac", address, ret); + break; + case 10: /* DC CVAC, gets promoted */ + __user_cache_maint("dc civac", address, ret); + break; + case 14: /* DC CIVAC */ + __user_cache_maint("dc civac", address, ret); + break; + case 5: /* IC IVAU */ + __user_cache_maint("ic ivau", address, ret); + break; + default: + force_signal_inject(SIGILL, ILL_ILLOPC, regs, 0); + return; + } + } else { + force_signal_inject(SIGILL, ILL_ILLOPC, regs, 0); + return; + } + + if (ret) + arm64_notify_segfault(regs, address); + else + regs->pc += 4; } long compat_arm_syscall(struct pt_regs *regs); @@ -465,7 +553,7 @@ static const char *esr_class_str[] = { const char *esr_get_class_string(u32 esr) { - return esr_class_str[esr >> ESR_ELx_EC_SHIFT]; + return esr_class_str[ESR_ELx_EC(esr)]; } /* -- cgit v1.2.3-54-g00ecf