Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 210 insertions, 0 deletions

diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
new file mode 100644
index 000000000..3327c47bc
--- /dev/null
+++ b/arch/s390/mm/mmap.c
@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  flexible mmap layout support
+ *
+ * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
+ * All Rights Reserved.
+ *
+ * Started by Ingo Molnar <mingo@elte.hu>
+ */
+
+#include <linux/elf-randomize.h>
+#include <linux/personality.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/mm.h>
+#include <linux/random.h>
+#include <linux/compat.h>
+#include <linux/security.h>
+#include <asm/elf.h>
+
+static unsigned long stack_maxrandom_size(void)
+{
+	if (!(current->flags & PF_RANDOMIZE))
+		return 0;
+	return STACK_RND_MASK << PAGE_SHIFT;
+}
+
+static inline int mmap_is_legacy(struct rlimit *rlim_stack)
+{
+	if (current->personality & ADDR_COMPAT_LAYOUT)
+		return 1;
+	if (rlim_stack->rlim_cur == RLIM_INFINITY)
+		return 1;
+	return sysctl_legacy_va_layout;
+}
+
+unsigned long arch_mmap_rnd(void)
+{
+	return (get_random_u32() & MMAP_RND_MASK) << PAGE_SHIFT;
+}
+
+static unsigned long mmap_base_legacy(unsigned long rnd)
+{
+	return TASK_UNMAPPED_BASE + rnd;
+}
+
+static inline unsigned long mmap_base(unsigned long rnd,
+				      struct rlimit *rlim_stack)
+{
+	unsigned long gap = rlim_stack->rlim_cur;
+	unsigned long pad = stack_maxrandom_size() + stack_guard_gap;
+	unsigned long gap_min, gap_max;
+
+	/* Values close to RLIM_INFINITY can overflow. */
+	if (gap + pad > gap)
+		gap += pad;
+
+	/*
+	 * Top of mmap area (just below the process stack).
+	 * Leave at least a ~128 MB hole.
+	 */
+	gap_min = SZ_128M;
+	gap_max = (STACK_TOP / 6) * 5;
+
+	if (gap < gap_min)
+		gap = gap_min;
+	else if (gap > gap_max)
+		gap = gap_max;
+
+	return PAGE_ALIGN(STACK_TOP - gap - rnd);
+}
+
+unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
+				     unsigned long len, unsigned long pgoff,
+				     unsigned long flags)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	struct vm_unmapped_area_info info;
+
+	if (len > TASK_SIZE - mmap_min_addr)
+		return -ENOMEM;
+
+	if (flags & MAP_FIXED)
+		goto check_asce_limit;
+
+	if (addr) {
+		addr = PAGE_ALIGN(addr);
+		vma = find_vma(mm, addr);
+		if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
+		    (!vma || addr + len <= vm_start_gap(vma)))
+			goto check_asce_limit;
+	}
+
+	info.flags = 0;
+	info.length = len;
+	info.low_limit = mm->mmap_base;
+	info.high_limit = TASK_SIZE;
+	if (filp || (flags & MAP_SHARED))
+		info.align_mask = MMAP_ALIGN_MASK << PAGE_SHIFT;
+	else
+		info.align_mask = 0;
+	info.align_offset = pgoff << PAGE_SHIFT;
+	addr = vm_unmapped_area(&info);
+	if (offset_in_page(addr))
+		return addr;
+
+check_asce_limit:
+	return check_asce_limit(mm, addr, len);
+}
+
+unsigned long arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
+					     unsigned long len, unsigned long pgoff,
+					     unsigned long flags)
+{
+	struct vm_area_struct *vma;
+	struct mm_struct *mm = current->mm;
+	struct vm_unmapped_area_info info;
+
+	/* requested length too big for entire address space */
+	if (len > TASK_SIZE - mmap_min_addr)
+		return -ENOMEM;
+
+	if (flags & MAP_FIXED)
+		goto check_asce_limit;
+
+	/* requesting a specific address */
+	if (addr) {
+		addr = PAGE_ALIGN(addr);
+		vma = find_vma(mm, addr);
+		if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
+				(!vma || addr + len <= vm_start_gap(vma)))
+			goto check_asce_limit;
+	}
+
+	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
+	info.length = len;
+	info.low_limit = max(PAGE_SIZE, mmap_min_addr);
+	info.high_limit = mm->mmap_base;
+	if (filp || (flags & MAP_SHARED))
+		info.align_mask = MMAP_ALIGN_MASK << PAGE_SHIFT;
+	else
+		info.align_mask = 0;
+	info.align_offset = pgoff << PAGE_SHIFT;
+	addr = vm_unmapped_area(&info);
+
+	/*
+	 * A failed mmap() very likely causes application failure,
+	 * so fall back to the bottom-up function here. This scenario
+	 * can happen with large stack limits and large mmap()
+	 * allocations.
+	 */
+	if (offset_in_page(addr)) {
+		VM_BUG_ON(addr != -ENOMEM);
+		info.flags = 0;
+		info.low_limit = TASK_UNMAPPED_BASE;
+		info.high_limit = TASK_SIZE;
+		addr = vm_unmapped_area(&info);
+		if (offset_in_page(addr))
+			return addr;
+	}
+
+check_asce_limit:
+	return check_asce_limit(mm, addr, len);
+}
+
+/*
+ * This function, called very early during the creation of a new
+ * process VM image, sets up which VM layout function to use:
+ */
+void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack)
+{
+	unsigned long random_factor = 0UL;
+
+	if (current->flags & PF_RANDOMIZE)
+		random_factor = arch_mmap_rnd();
+
+	/*
+	 * Fall back to the standard layout if the personality
+	 * bit is set, or if the expected stack growth is unlimited:
+	 */
+	if (mmap_is_legacy(rlim_stack)) {
+		mm->mmap_base = mmap_base_legacy(random_factor);
+		mm->get_unmapped_area = arch_get_unmapped_area;
+	} else {
+		mm->mmap_base = mmap_base(random_factor, rlim_stack);
+		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
+	}
+}
+
+static const pgprot_t protection_map[16] = {
+	[VM_NONE]					= PAGE_NONE,
+	[VM_READ]					= PAGE_RO,
+	[VM_WRITE]					= PAGE_RO,
+	[VM_WRITE | VM_READ]				= PAGE_RO,
+	[VM_EXEC]					= PAGE_RX,
+	[VM_EXEC | VM_READ]				= PAGE_RX,
+	[VM_EXEC | VM_WRITE]				= PAGE_RX,
+	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_RX,
+	[VM_SHARED]					= PAGE_NONE,
+	[VM_SHARED | VM_READ]				= PAGE_RO,
+	[VM_SHARED | VM_WRITE]				= PAGE_RW,
+	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_RW,
+	[VM_SHARED | VM_EXEC]				= PAGE_RX,
+	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_RX,
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_RWX,
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_RWX
+};
+DECLARE_VM_GET_PAGE_PROT