Patch "powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation" has been added to the 4.14-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     powerpc-64s-radix-fix-128tb-512tb-virtual-address-boundary-case-allocation.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 85e3f1adcb9d49300b0a943bb93f9604be375bfb Mon Sep 17 00:00:00 2001
From: Nicholas Piggin <npiggin@gmail.com>
Date: Fri, 10 Nov 2017 04:27:39 +1100
Subject: powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation

From: Nicholas Piggin <npiggin@gmail.com>

commit 85e3f1adcb9d49300b0a943bb93f9604be375bfb upstream.

Radix VA space allocations test addresses against mm->task_size which
is 512TB, even in cases where the intention is to limit allocation to
below 128TB.

This results in mmap with a hint address below 128TB but address +
length above 128TB succeeding when it should fail (as hash does after
the previous patch).

Set the high address limit to be considered up front, and base
subsequent allocation checks on that consistently.

Fixes: f4ea6dcb08ea ("powerpc/mm: Enable mappings above 128TB")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/powerpc/mm/hugetlbpage-radix.c |   26 +++++++++++------
 arch/powerpc/mm/mmap.c              |   55 +++++++++++++++++++++---------------
 2 files changed, 50 insertions(+), 31 deletions(-)

--- a/arch/powerpc/mm/hugetlbpage-radix.c
+++ b/arch/powerpc/mm/hugetlbpage-radix.c
@@ -49,17 +49,28 @@ radix__hugetlb_get_unmapped_area(struct
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
 	struct hstate *h = hstate_file(file);
+	int fixed = (flags & MAP_FIXED);
+	unsigned long high_limit;
 	struct vm_unmapped_area_info info;
 
-	if (unlikely(addr > mm->context.addr_limit && addr < TASK_SIZE))
-		mm->context.addr_limit = TASK_SIZE;
+	high_limit = DEFAULT_MAP_WINDOW;
+	if (addr >= high_limit || (fixed && (addr + len > high_limit)))
+		high_limit = TASK_SIZE;
 
 	if (len & ~huge_page_mask(h))
 		return -EINVAL;
-	if (len > mm->task_size)
+	if (len > high_limit)
 		return -ENOMEM;
+	if (fixed) {
+		if (addr > high_limit - len)
+			return -ENOMEM;
+	}
 
-	if (flags & MAP_FIXED) {
+	if (unlikely(addr > mm->context.addr_limit &&
+		     mm->context.addr_limit != TASK_SIZE))
+		mm->context.addr_limit = TASK_SIZE;
+
+	if (fixed) {
 		if (prepare_hugepage_range(file, addr, len))
 			return -EINVAL;
 		return addr;
@@ -68,7 +79,7 @@ radix__hugetlb_get_unmapped_area(struct
 	if (addr) {
 		addr = ALIGN(addr, huge_page_size(h));
 		vma = find_vma(mm, addr);
-		if (mm->task_size - len >= addr &&
+		if (high_limit - len >= addr &&
 		    (!vma || addr + len <= vm_start_gap(vma)))
 			return addr;
 	}
@@ -79,12 +90,9 @@ radix__hugetlb_get_unmapped_area(struct
 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
 	info.length = len;
 	info.low_limit = PAGE_SIZE;
-	info.high_limit = current->mm->mmap_base;
+	info.high_limit = mm->mmap_base + (high_limit - DEFAULT_MAP_WINDOW);
 	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
 	info.align_offset = 0;
 
-	if (addr > DEFAULT_MAP_WINDOW)
-		info.high_limit += mm->context.addr_limit - DEFAULT_MAP_WINDOW;
-
 	return vm_unmapped_area(&info);
 }
--- a/arch/powerpc/mm/mmap.c
+++ b/arch/powerpc/mm/mmap.c
@@ -106,22 +106,32 @@ radix__arch_get_unmapped_area(struct fil
 {
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
+	int fixed = (flags & MAP_FIXED);
+	unsigned long high_limit;
 	struct vm_unmapped_area_info info;
 
+	high_limit = DEFAULT_MAP_WINDOW;
+	if (addr >= high_limit || (fixed && (addr + len > high_limit)))
+		high_limit = TASK_SIZE;
+
+	if (len > high_limit)
+		return -ENOMEM;
+	if (fixed) {
+		if (addr > high_limit - len)
+			return -ENOMEM;
+	}
+
 	if (unlikely(addr > mm->context.addr_limit &&
 		     mm->context.addr_limit != TASK_SIZE))
 		mm->context.addr_limit = TASK_SIZE;
 
-	if (len > mm->task_size - mmap_min_addr)
-		return -ENOMEM;
-
-	if (flags & MAP_FIXED)
+	if (fixed)
 		return addr;
 
 	if (addr) {
 		addr = PAGE_ALIGN(addr);
 		vma = find_vma(mm, addr);
-		if (mm->task_size - len >= addr && addr >= mmap_min_addr &&
+		if (high_limit - len >= addr && addr >= mmap_min_addr &&
 		    (!vma || addr + len <= vm_start_gap(vma)))
 			return addr;
 	}
@@ -129,13 +139,9 @@ radix__arch_get_unmapped_area(struct fil
 	info.flags = 0;
 	info.length = len;
 	info.low_limit = mm->mmap_base;
+	info.high_limit = high_limit;
 	info.align_mask = 0;
 
-	if (unlikely(addr > DEFAULT_MAP_WINDOW))
-		info.high_limit = mm->context.addr_limit;
-	else
-		info.high_limit = DEFAULT_MAP_WINDOW;
-
 	return vm_unmapped_area(&info);
 }
 
@@ -149,37 +155,42 @@ radix__arch_get_unmapped_area_topdown(st
 	struct vm_area_struct *vma;
 	struct mm_struct *mm = current->mm;
 	unsigned long addr = addr0;
+	int fixed = (flags & MAP_FIXED);
+	unsigned long high_limit;
 	struct vm_unmapped_area_info info;
 
+	high_limit = DEFAULT_MAP_WINDOW;
+	if (addr >= high_limit || (fixed && (addr + len > high_limit)))
+		high_limit = TASK_SIZE;
+
+	if (len > high_limit)
+		return -ENOMEM;
+	if (fixed) {
+		if (addr > high_limit - len)
+			return -ENOMEM;
+	}
+
 	if (unlikely(addr > mm->context.addr_limit &&
 		     mm->context.addr_limit != TASK_SIZE))
 		mm->context.addr_limit = TASK_SIZE;
 
-	/* requested length too big for entire address space */
-	if (len > mm->task_size - mmap_min_addr)
-		return -ENOMEM;
-
-	if (flags & MAP_FIXED)
+	if (fixed)
 		return addr;
 
-	/* requesting a specific address */
 	if (addr) {
 		addr = PAGE_ALIGN(addr);
 		vma = find_vma(mm, addr);
-		if (mm->task_size - len >= addr && addr >= mmap_min_addr &&
-				(!vma || addr + len <= vm_start_gap(vma)))
+		if (high_limit - len >= addr && addr >= mmap_min_addr &&
+		    (!vma || addr + len <= vm_start_gap(vma)))
 			return addr;
 	}
 
 	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
 	info.length = len;
 	info.low_limit = max(PAGE_SIZE, mmap_min_addr);
-	info.high_limit = mm->mmap_base;
+	info.high_limit = mm->mmap_base + (high_limit - DEFAULT_MAP_WINDOW);
 	info.align_mask = 0;
 
-	if (addr > DEFAULT_MAP_WINDOW)
-		info.high_limit += mm->context.addr_limit - DEFAULT_MAP_WINDOW;
-
 	addr = vm_unmapped_area(&info);
 	if (!(addr & ~PAGE_MASK))
 		return addr;


Patches currently in stable-queue which might be from npiggin@gmail.com are

queue-4.14/powerpc-64s-hash-fix-128tb-512tb-virtual-address-boundary-case-allocation.patch
queue-4.14/powerpc-64s-hash-fix-fork-with-512tb-process-address-space.patch
queue-4.14/powerpc-64s-radix-fix-128tb-512tb-virtual-address-boundary-case-allocation.patch
queue-4.14/powerpc-64s-hash-allow-map_fixed-allocations-to-cross-128tb-boundary.patch
queue-4.14/powerpc-64s-hash-fix-512t-hint-detection-to-use-128t.patch