Merge branch 'v4.4/topic/mm-kaslr' into linux-linaro-lsk-v4.4

[firefly-linux-kernel-4.4.55.git] / arch / arm64 / kernel / process.c

diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index f75b540bc3b4b0daae4a8773cd0eddf1a86a90aa..80624829db613961b7a088ce18d8591361b448c7 100644 (file)
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -46,6 +46,7 @@
 #include <linux/notifier.h>
 #include <trace/events/power.h>
 
+#include <asm/alternative.h>
 #include <asm/compat.h>
 #include <asm/cacheflush.h>
 #include <asm/fpsimd.h>
@@ -280,6 +281,9 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
        } else {
                memset(childregs, 0, sizeof(struct pt_regs));
                childregs->pstate = PSR_MODE_EL1h;
+               if (IS_ENABLED(CONFIG_ARM64_UAO) &&
+                   cpus_have_cap(ARM64_HAS_UAO))
+                       childregs->pstate |= PSR_UAO_BIT;
                p->thread.cpu_context.x19 = stack_start;
                p->thread.cpu_context.x20 = stk_sz;
        }
@@ -308,6 +312,17 @@ static void tls_thread_switch(struct task_struct *next)
        : : "r" (tpidr), "r" (tpidrro));
 }
 
+/* Restore the UAO state depending on next's addr_limit */
+static void uao_thread_switch(struct task_struct *next)
+{
+       if (IS_ENABLED(CONFIG_ARM64_UAO)) {
+               if (task_thread_info(next)->addr_limit == KERNEL_DS)
+                       asm(ALTERNATIVE("nop", SET_PSTATE_UAO(1), ARM64_HAS_UAO));
+               else
+                       asm(ALTERNATIVE("nop", SET_PSTATE_UAO(0), ARM64_HAS_UAO));
+       }
+}
+
 /*
  * Thread switching.
  */
@@ -320,6 +335,7 @@ struct task_struct *__switch_to(struct task_struct *prev,
        tls_thread_switch(next);
        hw_breakpoint_thread_switch(next);
        contextidr_thread_switch(next);
+       uao_thread_switch(next);
 
        /*
         * Complete any pending TLB or cache maintenance on this CPU in case
@@ -344,11 +360,14 @@ unsigned long get_wchan(struct task_struct *p)
        frame.fp = thread_saved_fp(p);
        frame.sp = thread_saved_sp(p);
        frame.pc = thread_saved_pc(p);
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+       frame.graph = p->curr_ret_stack;
+#endif
        stack_page = (unsigned long)task_stack_page(p);
        do {
                if (frame.sp < stack_page ||
                    frame.sp >= stack_page + THREAD_SIZE ||
-                   unwind_frame(&frame))
+                   unwind_frame(p, &frame))
                        return 0;
                if (!in_sched_functions(frame.pc))
                        return frame.pc;