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-rw-r--r--arch/arm64/kernel/module.c126
1 files changed, 0 insertions, 126 deletions
diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index 47e0be610b..36b25af563 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -12,144 +12,18 @@
#include <linux/bitops.h>
#include <linux/elf.h>
#include <linux/ftrace.h>
-#include <linux/gfp.h>
#include <linux/kasan.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/moduleloader.h>
#include <linux/random.h>
#include <linux/scs.h>
-#include <linux/vmalloc.h>
#include <asm/alternative.h>
#include <asm/insn.h>
#include <asm/scs.h>
#include <asm/sections.h>
-static u64 module_direct_base __ro_after_init = 0;
-static u64 module_plt_base __ro_after_init = 0;
-
-/*
- * Choose a random page-aligned base address for a window of 'size' bytes which
- * entirely contains the interval [start, end - 1].
- */
-static u64 __init random_bounding_box(u64 size, u64 start, u64 end)
-{
- u64 max_pgoff, pgoff;
-
- if ((end - start) >= size)
- return 0;
-
- max_pgoff = (size - (end - start)) / PAGE_SIZE;
- pgoff = get_random_u32_inclusive(0, max_pgoff);
-
- return start - pgoff * PAGE_SIZE;
-}
-
-/*
- * Modules may directly reference data and text anywhere within the kernel
- * image and other modules. References using PREL32 relocations have a +/-2G
- * range, and so we need to ensure that the entire kernel image and all modules
- * fall within a 2G window such that these are always within range.
- *
- * Modules may directly branch to functions and code within the kernel text,
- * and to functions and code within other modules. These branches will use
- * CALL26/JUMP26 relocations with a +/-128M range. Without PLTs, we must ensure
- * that the entire kernel text and all module text falls within a 128M window
- * such that these are always within range. With PLTs, we can expand this to a
- * 2G window.
- *
- * We chose the 128M region to surround the entire kernel image (rather than
- * just the text) as using the same bounds for the 128M and 2G regions ensures
- * by construction that we never select a 128M region that is not a subset of
- * the 2G region. For very large and unusual kernel configurations this means
- * we may fall back to PLTs where they could have been avoided, but this keeps
- * the logic significantly simpler.
- */
-static int __init module_init_limits(void)
-{
- u64 kernel_end = (u64)_end;
- u64 kernel_start = (u64)_text;
- u64 kernel_size = kernel_end - kernel_start;
-
- /*
- * The default modules region is placed immediately below the kernel
- * image, and is large enough to use the full 2G relocation range.
- */
- BUILD_BUG_ON(KIMAGE_VADDR != MODULES_END);
- BUILD_BUG_ON(MODULES_VSIZE < SZ_2G);
-
- if (!kaslr_enabled()) {
- if (kernel_size < SZ_128M)
- module_direct_base = kernel_end - SZ_128M;
- if (kernel_size < SZ_2G)
- module_plt_base = kernel_end - SZ_2G;
- } else {
- u64 min = kernel_start;
- u64 max = kernel_end;
-
- if (IS_ENABLED(CONFIG_RANDOMIZE_MODULE_REGION_FULL)) {
- pr_info("2G module region forced by RANDOMIZE_MODULE_REGION_FULL\n");
- } else {
- module_direct_base = random_bounding_box(SZ_128M, min, max);
- if (module_direct_base) {
- min = module_direct_base;
- max = module_direct_base + SZ_128M;
- }
- }
-
- module_plt_base = random_bounding_box(SZ_2G, min, max);
- }
-
- pr_info("%llu pages in range for non-PLT usage",
- module_direct_base ? (SZ_128M - kernel_size) / PAGE_SIZE : 0);
- pr_info("%llu pages in range for PLT usage",
- module_plt_base ? (SZ_2G - kernel_size) / PAGE_SIZE : 0);
-
- return 0;
-}
-subsys_initcall(module_init_limits);
-
-void *module_alloc(unsigned long size)
-{
- void *p = NULL;
-
- /*
- * Where possible, prefer to allocate within direct branch range of the
- * kernel such that no PLTs are necessary.
- */
- if (module_direct_base) {
- p = __vmalloc_node_range(size, MODULE_ALIGN,
- module_direct_base,
- module_direct_base + SZ_128M,
- GFP_KERNEL | __GFP_NOWARN,
- PAGE_KERNEL, 0, NUMA_NO_NODE,
- __builtin_return_address(0));
- }
-
- if (!p && module_plt_base) {
- p = __vmalloc_node_range(size, MODULE_ALIGN,
- module_plt_base,
- module_plt_base + SZ_2G,
- GFP_KERNEL | __GFP_NOWARN,
- PAGE_KERNEL, 0, NUMA_NO_NODE,
- __builtin_return_address(0));
- }
-
- if (!p) {
- pr_warn_ratelimited("%s: unable to allocate memory\n",
- __func__);
- }
-
- if (p && (kasan_alloc_module_shadow(p, size, GFP_KERNEL) < 0)) {
- vfree(p);
- return NULL;
- }
-
- /* Memory is intended to be executable, reset the pointer tag. */
- return kasan_reset_tag(p);
-}
-
enum aarch64_reloc_op {
RELOC_OP_NONE,
RELOC_OP_ABS,