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Diffstat (limited to 'arch/arm64/kernel/traps.c')
-rw-r--r--arch/arm64/kernel/traps.c152
1 files changed, 120 insertions, 32 deletions
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 2a43012616b7..e04f83873af7 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -41,6 +41,7 @@
#include <asm/stacktrace.h>
#include <asm/exception.h>
#include <asm/system_misc.h>
+#include <asm/sysreg.h>
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);
@@ -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(&current->mm->mmap_sem);
+ if (find_vma(current->mm, addr) == NULL)
+ code = SEGV_MAPERR;
+ else
+ code = SEGV_ACCERR;
+ up_read(&current->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);
+}
+
+#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;
- arm64_notify_die("Oops - undefined instruction", regs, &info, 0);
+ /* 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)];
}
/*
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.