Fix: Disable IBT around indirect function calls

[lttng-modules.git] / src / wrapper / page_alloc.c

diff --git a/src/wrapper/page_alloc.c b/src/wrapper/page_alloc.c
index 93504c993883244cb692ab192abef040148737d6..5e19d7b5c786accd74e0a9697ceb3af588dfc3ef 100644 (file)
--- a/src/wrapper/page_alloc.c
+++ b/src/wrapper/page_alloc.c
@@ -9,14 +9,7 @@
  * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  */
 
-#include <lttng/kernel-version.h>
-
-#if (defined(CONFIG_KALLSYMS) \
-       && (LINUX_VERSION_CODE >= KERNEL_VERSION(3,19,2)        \
-               || LTTNG_KERNEL_RANGE(3,14,36, 3,15,0)          \
-               || LTTNG_KERNEL_RANGE(3,18,10, 3,19,0)          \
-               || LTTNG_DEBIAN_KERNEL_RANGE(3,16,7,9,0,0, 3,17,0,0,0,0) \
-               || LTTNG_UBUNTU_KERNEL_RANGE(3,16,7,34, 3,17,0,0)))
+#ifdef CONFIG_KALLSYMS
 
 #include <linux/kallsyms.h>
 #include <linux/mm_types.h>
@@ -37,7 +30,13 @@ unsigned long wrapper_get_pfnblock_flags_mask(struct page *page,
 {
        WARN_ON_ONCE(!get_pfnblock_flags_mask_sym);
        if (get_pfnblock_flags_mask_sym) {
-               return get_pfnblock_flags_mask_sym(page, pfn, end_bitidx, mask);
+               struct irq_ibt_state irq_ibt_state;
+               unsigned long ret;
+
+               irq_ibt_state = wrapper_irq_ibt_save();
+               ret = get_pfnblock_flags_mask_sym(page, pfn, end_bitidx, mask);
+               wrapper_irq_ibt_restore(irq_ibt_state);
+               return ret;
        } else {
                return -ENOSYS;
        }
@@ -54,48 +53,24 @@ int wrapper_get_pfnblock_flags_mask_init(void)
 }
 EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask_init);
 
-#else
-
-#include <linux/pageblock-flags.h>
-
-#endif
-
-#if (defined(CONFIG_KALLSYMS) \
-       && LTTNG_UBUNTU_KERNEL_RANGE(3,13,11,50, 3,14,0,0))
-
-#include <linux/kallsyms.h>
-#include <linux/mm_types.h>
-#include <linux/module.h>
-#include <wrapper/kallsyms.h>
-#include <wrapper/page_alloc.h>
-
-static
-unsigned long (*get_pageblock_flags_mask_sym)(struct page *page,
-               unsigned long end_bitidx,
-               unsigned long mask);
-
-unsigned long wrapper_get_pageblock_flags_mask(struct page *page,
-               unsigned long end_bitidx,
-               unsigned long mask)
-{
-       WARN_ON_ONCE(!get_pageblock_flags_mask_sym);
-       if (get_pageblock_flags_mask_sym) {
-               return get_pageblock_flags_mask_sym(page, end_bitidx, mask);
-       } else {
-               return -ENOSYS;
-       }
-}
-EXPORT_SYMBOL_GPL(wrapper_get_pageblock_flags_mask);
-
-int wrapper_get_pageblock_flags_mask_init(void)
+/*
+ * Canary function to check for 'get_pfnblock_flags_mask()' at compile time.
+ *
+ * From 'include/linux/pageblock-flags.h':
+ *
+ *   unsigned long get_pfnblock_flags_mask(struct page *page,
+ *                                         unsigned long pfn,
+ *                                         unsigned long end_bitidx,
+ *                                         unsigned long mask);
+ */
+__attribute__((unused)) static
+unsigned long __canary__get_pfnblock_flags_mask(struct page *page,
+                                               unsigned long pfn,
+                                               unsigned long end_bitidx,
+                                               unsigned long mask)
 {
-       get_pageblock_flags_mask_sym =
-               (void *) kallsyms_lookup_funcptr("get_pageblock_flags_mask");
-       if (!get_pageblock_flags_mask_sym)
-               return -1;
-       return 0;
+       return get_pfnblock_flags_mask(page, pfn, end_bitidx, mask);
 }
-EXPORT_SYMBOL_GPL(wrapper_get_pfnblock_flags_mask_init);
 
 #else