Merge tag 'v3.15-rc1' into patchwork

Linux 3.15-rc1

* tag 'v3.15-rc1': (12180 commits)
  Linux 3.15-rc1
  mm: Initialize error in shmem_file_aio_read()
  cifs: Use min_t() when comparing "size_t" and "unsigned long"
  sym53c8xx_2: Set DID_REQUEUE return code when aborting squeue
  powerpc: Don't try to set LPCR unless we're in hypervisor mode
  futex: update documentation for ordering guarantees
  ceph: fix pr_fmt() redefinition
  vti: don't allow to add the same tunnel twice
  gre: don't allow to add the same tunnel twice
  drivers: net: xen-netfront: fix array initialization bug
  missing bits of "splice: fix racy pipe->buffers uses"
  cifs: fix the race in cifs_writev()
  ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
  pktgen: be friendly to LLTX devices
  r8152: check RTL8152_UNPLUG
  net: sun4i-emac: add promiscuous support
  net/apne: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
  blackfin: cleanup board files
  bf609: clock: drop unused clock bit set/clear functions
  Blackfin: bf537: rename "CONFIG_ADT75"
  ...

1 files changed, 43 insertions, 3 deletions

diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 18be189368b..e69f9882bf9 100644
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -28,6 +28,7 @@
 #include <linux/mm.h>
 #include <linux/gfp.h>
 #include <linux/jump_label.h>
+#include <linux/random.h>
 
 #include <asm/page.h>
 #include <asm/pgtable.h>
@@ -43,13 +44,52 @@ do {							\
 } while (0)
 #endif
 
+#ifdef CONFIG_RANDOMIZE_BASE
+static unsigned long module_load_offset;
+static int randomize_modules = 1;
+
+/* Mutex protects the module_load_offset. */
+static DEFINE_MUTEX(module_kaslr_mutex);
+
+static int __init parse_nokaslr(char *p)
+{
+	randomize_modules = 0;
+	return 0;
+}
+early_param("nokaslr", parse_nokaslr);
+
+static unsigned long int get_module_load_offset(void)
+{
+	if (randomize_modules) {
+		mutex_lock(&module_kaslr_mutex);
+		/*
+		 * Calculate the module_load_offset the first time this
+		 * code is called. Once calculated it stays the same until
+		 * reboot.
+		 */
+		if (module_load_offset == 0)
+			module_load_offset =
+				(get_random_int() % 1024 + 1) * PAGE_SIZE;
+		mutex_unlock(&module_kaslr_mutex);
+	}
+	return module_load_offset;
+}
+#else
+static unsigned long int get_module_load_offset(void)
+{
+	return 0;
+}
+#endif
+
 void *module_alloc(unsigned long size)
 {
 	if (PAGE_ALIGN(size) > MODULES_LEN)
 		return NULL;
-	return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
-				GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC,
-				NUMA_NO_NODE, __builtin_return_address(0));
+	return __vmalloc_node_range(size, 1,
+				    MODULES_VADDR + get_module_load_offset(),
+				    MODULES_END, GFP_KERNEL | __GFP_HIGHMEM,
+				    PAGE_KERNEL_EXEC, NUMA_NO_NODE,
+				    __builtin_return_address(0));
 }
 
 #ifdef CONFIG_X86_32