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authorLaura Abbott <lauraa@codeaurora.org>2014-08-19 20:41:43 +0100
committerWill Deacon <will.deacon@arm.com>2014-09-08 14:39:18 +0100
commit11d91a770f1fff44dafdf88d6089a3451f99c9b6 (patch)
treedb7874516b61d7df4d85e4529b9ea6e1033624e6 /arch/arm64/mm/pageattr.c
parentb6d4f2800b7bad654caf00654f4bff21594ef838 (diff)
arm64: Add CONFIG_DEBUG_SET_MODULE_RONX support
In a similar fashion to other architecture, add the infrastructure and Kconfig to enable DEBUG_SET_MODULE_RONX support. When enabled, module ranges will be marked read-only/no-execute as appropriate. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> [will: fixed off-by-one in module end check] Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/mm/pageattr.c')
-rw-r--r--arch/arm64/mm/pageattr.c96
1 files changed, 96 insertions, 0 deletions
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
new file mode 100644
index 000000000000..75e744e4cec5
--- /dev/null
+++ b/arch/arm64/mm/pageattr.c
@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2014, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+
+struct page_change_data {
+ pgprot_t set_mask;
+ pgprot_t clear_mask;
+};
+
+static int change_page_range(pte_t *ptep, pgtable_t token, unsigned long addr,
+ void *data)
+{
+ struct page_change_data *cdata = data;
+ pte_t pte = *ptep;
+
+ pte = clear_pte_bit(pte, cdata->clear_mask);
+ pte = set_pte_bit(pte, cdata->set_mask);
+
+ set_pte(ptep, pte);
+ return 0;
+}
+
+static int change_memory_common(unsigned long addr, int numpages,
+ pgprot_t set_mask, pgprot_t clear_mask)
+{
+ unsigned long start = addr;
+ unsigned long size = PAGE_SIZE*numpages;
+ unsigned long end = start + size;
+ int ret;
+ struct page_change_data data;
+
+ if (!IS_ALIGNED(addr, PAGE_SIZE)) {
+ addr &= PAGE_MASK;
+ WARN_ON_ONCE(1);
+ }
+
+ if (!is_module_address(start) || !is_module_address(end - 1))
+ return -EINVAL;
+
+ data.set_mask = set_mask;
+ data.clear_mask = clear_mask;
+
+ ret = apply_to_page_range(&init_mm, start, size, change_page_range,
+ &data);
+
+ flush_tlb_kernel_range(start, end);
+ return ret;
+}
+
+int set_memory_ro(unsigned long addr, int numpages)
+{
+ return change_memory_common(addr, numpages,
+ __pgprot(PTE_RDONLY),
+ __pgprot(PTE_WRITE));
+}
+EXPORT_SYMBOL_GPL(set_memory_ro);
+
+int set_memory_rw(unsigned long addr, int numpages)
+{
+ return change_memory_common(addr, numpages,
+ __pgprot(PTE_WRITE),
+ __pgprot(PTE_RDONLY));
+}
+EXPORT_SYMBOL_GPL(set_memory_rw);
+
+int set_memory_nx(unsigned long addr, int numpages)
+{
+ return change_memory_common(addr, numpages,
+ __pgprot(PTE_PXN),
+ __pgprot(0));
+}
+EXPORT_SYMBOL_GPL(set_memory_nx);
+
+int set_memory_x(unsigned long addr, int numpages)
+{
+ return change_memory_common(addr, numpages,
+ __pgprot(0),
+ __pgprot(PTE_PXN));
+}
+EXPORT_SYMBOL_GPL(set_memory_x);