sched: Fix up scheduler syscall LTP fails

[firefly-linux-kernel-4.4.55.git] / kernel / futex.c

diff --git a/kernel/futex.c b/kernel/futex.c
index 80ba086f021d3022afcf3f06ecdb1d920cdc8f7c..679531c61d962bc9ce218f82d62e2becfb47eae9 100644 (file)
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -251,6 +251,9 @@ get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key, int rw)
                return -EINVAL;
        address -= key->both.offset;
 
+       if (unlikely(!access_ok(rw, uaddr, sizeof(u32))))
+               return -EFAULT;
+
        /*
         * PROCESS_PRIVATE futexes are fast.
         * As the mm cannot disappear under us and the 'key' only needs
@@ -259,8 +262,6 @@ get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key, int rw)
         *        but access_ok() should be faster than find_vma()
         */
        if (!fshared) {
-               if (unlikely(!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))))
-                       return -EFAULT;
                key->private.mm = mm;
                key->private.address = address;
                get_futex_key_refs(key);
@@ -288,7 +289,7 @@ again:
                put_page(page);
                /* serialize against __split_huge_page_splitting() */
                local_irq_disable();
-               if (likely(__get_user_pages_fast(address, 1, 1, &page) == 1)) {
+               if (likely(__get_user_pages_fast(address, 1, !ro, &page) == 1)) {
                        page_head = compound_head(page);
                        /*
                         * page_head is valid pointer but we must pin
@@ -2315,6 +2316,8 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
         * code while we sleep on uaddr.
         */
        debug_rt_mutex_init_waiter(&rt_waiter);
+       RB_CLEAR_NODE(&rt_waiter.pi_tree_entry);
+       RB_CLEAR_NODE(&rt_waiter.tree_entry);
        rt_waiter.task = NULL;
 
        ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, VERIFY_WRITE);