Merge 4.4.74 into android-4.4

Changes in 4.4.74
	configfs: Fix race between create_link and configfs_rmdir
	can: gs_usb: fix memory leak in gs_cmd_reset()
	cpufreq: conservative: Allow down_threshold to take values from 1 to 10
	vb2: Fix an off by one error in 'vb2_plane_vaddr'
	mac80211: don't look at the PM bit of BAR frames
	mac80211/wpa: use constant time memory comparison for MACs
	mac80211: fix CSA in IBSS mode
	mac80211: fix IBSS presp allocation size
	serial: efm32: Fix parity management in 'efm32_uart_console_get_options()'
	x86/mm/32: Set the '__vmalloc_start_set' flag in initmem_init()
	mfd: omap-usb-tll: Fix inverted bit use for USB TLL mode
	staging: rtl8188eu: prevent an underflow in rtw_check_beacon_data()
	iio: proximity: as3935: recalibrate RCO after resume
	USB: hub: fix SS max number of ports
	usb: core: fix potential memory leak in error path during hcd creation
	pvrusb2: reduce stack usage pvr2_eeprom_analyze()
	USB: gadget: dummy_hcd: fix hub-descriptor removable fields
	usb: r8a66597-hcd: select a different endpoint on timeout
	usb: r8a66597-hcd: decrease timeout
	drivers/misc/c2port/c2port-duramar2150.c: checking for NULL instead of IS_ERR()
	usb: xhci: ASMedia ASM1042A chipset need shorts TX quirk
	USB: gadgetfs, dummy-hcd, net2280: fix locking for callbacks
	mm/memory-failure.c: use compound_head() flags for huge pages
	swap: cond_resched in swap_cgroup_prepare()
	genirq: Release resources in __setup_irq() error path
	alarmtimer: Prevent overflow of relative timers
	usb: dwc3: exynos fix axius clock error path to do cleanup
	MIPS: Fix bnezc/jialc return address calculation
	alarmtimer: Rate limit periodic intervals
	mm: larger stack guard gap, between vmas
	Allow stack to grow up to address space limit
	mm: fix new crash in unmapped_area_topdown()
	Linux 4.4.74

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

1 files changed, 25 insertions, 28 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index f8a729751faa..e51aafbc4b3a 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1290,39 +1290,11 @@ int clear_page_dirty_for_io(struct page *page);
 
 int get_cmdline(struct task_struct *task, char *buffer, int buflen);
 
-/* Is the vma a continuation of the stack vma above it? */
-static inline int vma_growsdown(struct vm_area_struct *vma, unsigned long addr)
-{
-	return vma && (vma->vm_end == addr) && (vma->vm_flags & VM_GROWSDOWN);
-}
-
 static inline bool vma_is_anonymous(struct vm_area_struct *vma)
 {
 	return !vma->vm_ops;
 }
 
-static inline int stack_guard_page_start(struct vm_area_struct *vma,
-					     unsigned long addr)
-{
-	return (vma->vm_flags & VM_GROWSDOWN) &&
-		(vma->vm_start == addr) &&
-		!vma_growsdown(vma->vm_prev, addr);
-}
-
-/* Is the vma a continuation of the stack vma below it? */
-static inline int vma_growsup(struct vm_area_struct *vma, unsigned long addr)
-{
-	return vma && (vma->vm_start == addr) && (vma->vm_flags & VM_GROWSUP);
-}
-
-static inline int stack_guard_page_end(struct vm_area_struct *vma,
-					   unsigned long addr)
-{
-	return (vma->vm_flags & VM_GROWSUP) &&
-		(vma->vm_end == addr) &&
-		!vma_growsup(vma->vm_next, addr);
-}
-
 int vma_is_stack_for_task(struct vm_area_struct *vma, struct task_struct *t);
 
 extern unsigned long move_page_tables(struct vm_area_struct *vma,
@@ -2024,6 +1996,7 @@ void page_cache_async_readahead(struct address_space *mapping,
 				pgoff_t offset,
 				unsigned long size);
 
+extern unsigned long stack_guard_gap;
 /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
 extern int expand_stack(struct vm_area_struct *vma, unsigned long address);
 
@@ -2052,6 +2025,30 @@ static inline struct vm_area_struct * find_vma_intersection(struct mm_struct * m
 	return vma;
 }
 
+static inline unsigned long vm_start_gap(struct vm_area_struct *vma)
+{
+	unsigned long vm_start = vma->vm_start;
+
+	if (vma->vm_flags & VM_GROWSDOWN) {
+		vm_start -= stack_guard_gap;
+		if (vm_start > vma->vm_start)
+			vm_start = 0;
+	}
+	return vm_start;
+}
+
+static inline unsigned long vm_end_gap(struct vm_area_struct *vma)
+{
+	unsigned long vm_end = vma->vm_end;
+
+	if (vma->vm_flags & VM_GROWSUP) {
+		vm_end += stack_guard_gap;
+		if (vm_end < vma->vm_end)
+			vm_end = -PAGE_SIZE;
+	}
+	return vm_end;
+}
+
 static inline unsigned long vma_pages(struct vm_area_struct *vma)
 {
 	return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;