1 files changed, 70 insertions, 156 deletions

diff --git a/arch/riscv/kernel/vdso.c b/arch/riscv/kernel/vdso.c
index a9436a65161a..3a8e038b10a2 100644
--- a/arch/riscv/kernel/vdso.c
+++ b/arch/riscv/kernel/vdso.c
@@ -13,50 +13,25 @@
 #include <linux/err.h>
 #include <asm/page.h>
 #include <asm/vdso.h>
-#include <linux/time_namespace.h>
-
-#ifdef CONFIG_GENERIC_TIME_VSYSCALL
+#include <linux/vdso_datastore.h>
 #include <vdso/datapage.h>
-#else
-struct vdso_data {
-};
-#endif
+#include <vdso/vsyscall.h>
 
-extern char vdso_start[], vdso_end[];
-
-enum vvar_pages {
-	VVAR_DATA_PAGE_OFFSET,
-	VVAR_TIMENS_PAGE_OFFSET,
-	VVAR_NR_PAGES,
-};
-
-#define VVAR_SIZE  (VVAR_NR_PAGES << PAGE_SHIFT)
-
-/*
- * The vDSO data page.
- */
-static union {
-	struct vdso_data	data;
-	u8			page[PAGE_SIZE];
-} vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = &vdso_data_store.data;
+#define VVAR_SIZE  (VDSO_NR_PAGES << PAGE_SHIFT)
 
 struct __vdso_info {
 	const char *name;
 	const char *vdso_code_start;
 	const char *vdso_code_end;
 	unsigned long vdso_pages;
-	/* Data Mapping */
-	struct vm_special_mapping *dm;
 	/* Code Mapping */
 	struct vm_special_mapping *cm;
 };
 
-static struct __vdso_info vdso_info __ro_after_init = {
-	.name = "vdso",
-	.vdso_code_start = vdso_start,
-	.vdso_code_end = vdso_end,
-};
+static struct __vdso_info vdso_info;
+#ifdef CONFIG_COMPAT
+static struct __vdso_info compat_vdso_info;
+#endif
 
 static int vdso_mremap(const struct vm_special_mapping *sm,
 		       struct vm_area_struct *new_vma)
@@ -66,162 +41,83 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
 	return 0;
 }
 
-static int __init __vdso_init(void)
+static void __init __vdso_init(struct __vdso_info *vdso_info)
 {
 	unsigned int i;
 	struct page **vdso_pagelist;
 	unsigned long pfn;
 
-	if (memcmp(vdso_info.vdso_code_start, "\177ELF", 4)) {
-		pr_err("vDSO is not a valid ELF object!\n");
-		return -EINVAL;
-	}
+	if (memcmp(vdso_info->vdso_code_start, "\177ELF", 4))
+		panic("vDSO is not a valid ELF object!\n");
 
-	vdso_info.vdso_pages = (
-		vdso_info.vdso_code_end -
-		vdso_info.vdso_code_start) >>
+	vdso_info->vdso_pages = (
+		vdso_info->vdso_code_end -
+		vdso_info->vdso_code_start) >>
 		PAGE_SHIFT;
 
-	vdso_pagelist = kcalloc(vdso_info.vdso_pages,
+	vdso_pagelist = kcalloc(vdso_info->vdso_pages,
 				sizeof(struct page *),
 				GFP_KERNEL);
 	if (vdso_pagelist == NULL)
-		return -ENOMEM;
+		panic("vDSO kcalloc failed!\n");
 
 	/* Grab the vDSO code pages. */
-	pfn = sym_to_pfn(vdso_info.vdso_code_start);
+	pfn = sym_to_pfn(vdso_info->vdso_code_start);
 
-	for (i = 0; i < vdso_info.vdso_pages; i++)
+	for (i = 0; i < vdso_info->vdso_pages; i++)
 		vdso_pagelist[i] = pfn_to_page(pfn + i);
 
-	vdso_info.cm->pages = vdso_pagelist;
-
-	return 0;
-}
-
-#ifdef CONFIG_TIME_NS
-struct vdso_data *arch_get_vdso_data(void *vvar_page)
-{
-	return (struct vdso_data *)(vvar_page);
-}
-
-/*
- * The vvar mapping contains data for a specific time namespace, so when a task
- * changes namespace we must unmap its vvar data for the old namespace.
- * Subsequent faults will map in data for the new namespace.
- *
- * For more details see timens_setup_vdso_data().
- */
-int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
-{
-	struct mm_struct *mm = task->mm;
-	struct vm_area_struct *vma;
-
-	mmap_read_lock(mm);
-
-	for (vma = mm->mmap; vma; vma = vma->vm_next) {
-		unsigned long size = vma->vm_end - vma->vm_start;
-
-		if (vma_is_special_mapping(vma, vdso_info.dm))
-			zap_page_range(vma, vma->vm_start, size);
-	}
-
-	mmap_read_unlock(mm);
-	return 0;
-}
-
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	if (likely(vma->vm_mm == current->mm))
-		return current->nsproxy->time_ns->vvar_page;
-
-	/*
-	 * VM_PFNMAP | VM_IO protect .fault() handler from being called
-	 * through interfaces like /proc/$pid/mem or
-	 * process_vm_{readv,writev}() as long as there's no .access()
-	 * in special_mapping_vmops.
-	 * For more details check_vma_flags() and __access_remote_vm()
-	 */
-	WARN(1, "vvar_page accessed remotely");
-
-	return NULL;
+	vdso_info->cm->pages = vdso_pagelist;
 }
-#else
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	return NULL;
-}
-#endif
 
-static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
-			     struct vm_area_struct *vma, struct vm_fault *vmf)
-{
-	struct page *timens_page = find_timens_vvar_page(vma);
-	unsigned long pfn;
-
-	switch (vmf->pgoff) {
-	case VVAR_DATA_PAGE_OFFSET:
-		if (timens_page)
-			pfn = page_to_pfn(timens_page);
-		else
-			pfn = sym_to_pfn(vdso_data);
-		break;
-#ifdef CONFIG_TIME_NS
-	case VVAR_TIMENS_PAGE_OFFSET:
-		/*
-		 * If a task belongs to a time namespace then a namespace
-		 * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and
-		 * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET
-		 * offset.
-		 * See also the comment near timens_setup_vdso_data().
-		 */
-		if (!timens_page)
-			return VM_FAULT_SIGBUS;
-		pfn = sym_to_pfn(vdso_data);
-		break;
-#endif /* CONFIG_TIME_NS */
-	default:
-		return VM_FAULT_SIGBUS;
-	}
+static struct vm_special_mapping rv_vdso_map __ro_after_init = {
+	.name   = "[vdso]",
+	.mremap = vdso_mremap,
+};
 
-	return vmf_insert_pfn(vma, vmf->address, pfn);
-}
+static struct __vdso_info vdso_info __ro_after_init = {
+	.name = "vdso",
+	.vdso_code_start = vdso_start,
+	.vdso_code_end = vdso_end,
+	.cm = &rv_vdso_map,
+};
 
-enum rv_vdso_map {
-	RV_VDSO_MAP_VVAR,
-	RV_VDSO_MAP_VDSO,
+#ifdef CONFIG_COMPAT
+static struct vm_special_mapping rv_compat_vdso_map __ro_after_init = {
+	.name   = "[vdso]",
+	.mremap = vdso_mremap,
 };
 
-static struct vm_special_mapping rv_vdso_maps[] __ro_after_init = {
-	[RV_VDSO_MAP_VVAR] = {
-		.name   = "[vvar]",
-		.fault = vvar_fault,
-	},
-	[RV_VDSO_MAP_VDSO] = {
-		.name   = "[vdso]",
-		.mremap = vdso_mremap,
-	},
+static struct __vdso_info compat_vdso_info __ro_after_init = {
+	.name = "compat_vdso",
+	.vdso_code_start = compat_vdso_start,
+	.vdso_code_end = compat_vdso_end,
+	.cm = &rv_compat_vdso_map,
 };
+#endif
 
 static int __init vdso_init(void)
 {
-	vdso_info.dm = &rv_vdso_maps[RV_VDSO_MAP_VVAR];
-	vdso_info.cm = &rv_vdso_maps[RV_VDSO_MAP_VDSO];
+	__vdso_init(&vdso_info);
+#ifdef CONFIG_COMPAT
+	__vdso_init(&compat_vdso_info);
+#endif
 
-	return __vdso_init();
+	return 0;
 }
 arch_initcall(vdso_init);
 
 static int __setup_additional_pages(struct mm_struct *mm,
 				    struct linux_binprm *bprm,
-				    int uses_interp)
+				    int uses_interp,
+				    struct __vdso_info *vdso_info)
 {
 	unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
 	void *ret;
 
-	BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
+	BUILD_BUG_ON(VDSO_NR_PAGES != __VDSO_PAGES);
 
-	vdso_text_len = vdso_info.vdso_pages << PAGE_SHIFT;
+	vdso_text_len = vdso_info->vdso_pages << PAGE_SHIFT;
 	/* Be sure to map the data page */
 	vdso_mapping_len = vdso_text_len + VVAR_SIZE;
 
@@ -231,17 +127,17 @@ static int __setup_additional_pages(struct mm_struct *mm,
 		goto up_fail;
 	}
 
-	ret = _install_special_mapping(mm, vdso_base, VVAR_SIZE,
-		(VM_READ | VM_MAYREAD | VM_PFNMAP), vdso_info.dm);
+	ret = vdso_install_vvar_mapping(mm, vdso_base);
 	if (IS_ERR(ret))
 		goto up_fail;
 
 	vdso_base += VVAR_SIZE;
 	mm->context.vdso = (void *)vdso_base;
+
 	ret =
 	   _install_special_mapping(mm, vdso_base, vdso_text_len,
-		(VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC),
-		vdso_info.cm);
+		(VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC | VM_SEALED_SYSMAP),
+		vdso_info->cm);
 
 	if (IS_ERR(ret))
 		goto up_fail;
@@ -253,6 +149,24 @@ up_fail:
 	return PTR_ERR(ret);
 }
 
+#ifdef CONFIG_COMPAT
+int compat_arch_setup_additional_pages(struct linux_binprm *bprm,
+				       int uses_interp)
+{
+	struct mm_struct *mm = current->mm;
+	int ret;
+
+	if (mmap_write_lock_killable(mm))
+		return -EINTR;
+
+	ret = __setup_additional_pages(mm, bprm, uses_interp,
+							&compat_vdso_info);
+	mmap_write_unlock(mm);
+
+	return ret;
+}
+#endif
+
 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 {
 	struct mm_struct *mm = current->mm;
@@ -261,7 +175,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 	if (mmap_write_lock_killable(mm))
 		return -EINTR;
 
-	ret = __setup_additional_pages(mm, bprm, uses_interp);
+	ret = __setup_additional_pages(mm, bprm, uses_interp, &vdso_info);
 	mmap_write_unlock(mm);
 
 	return ret;