Merge 4.4.70 into android-4.4

Changes in 4.4.70
	usb: misc: legousbtower: Fix buffers on stack
	usb: misc: legousbtower: Fix memory leak
	USB: ene_usb6250: fix DMA to the stack
	watchdog: pcwd_usb: fix NULL-deref at probe
	char: lp: fix possible integer overflow in lp_setup()
	USB: core: replace %p with %pK
	ARM: tegra: paz00: Mark panel regulator as enabled on boot
	tpm_crb: check for bad response size
	infiniband: call ipv6 route lookup via the stub interface
	dm btree: fix for dm_btree_find_lowest_key()
	dm raid: select the Kconfig option CONFIG_MD_RAID0
	dm bufio: avoid a possible ABBA deadlock
	dm bufio: check new buffer allocation watermark every 30 seconds
	dm cache metadata: fail operations if fail_io mode has been established
	dm bufio: make the parameter "retain_bytes" unsigned long
	dm thin metadata: call precommit before saving the roots
	dm space map disk: fix some book keeping in the disk space map
	md: update slab_cache before releasing new stripes when stripes resizing
	rtlwifi: rtl8821ae: setup 8812ae RFE according to device type
	mwifiex: pcie: fix cmd_buf use-after-free in remove/reset
	ima: accept previously set IMA_NEW_FILE
	KVM: x86: Fix load damaged SSEx MXCSR register
	KVM: X86: Fix read out-of-bounds vulnerability in kvm pio emulation
	regulator: tps65023: Fix inverted core enable logic.
	s390/kdump: Add final note
	s390/cputime: fix incorrect system time
	ath9k_htc: Add support of AirTies 1eda:2315 AR9271 device
	ath9k_htc: fix NULL-deref at probe
	drm/amdgpu: Avoid overflows/divide-by-zero in latency_watermark calculations.
	drm/amdgpu: Make display watermark calculations more accurate
	drm/nouveau/therm: remove ineffective workarounds for alarm bugs
	drm/nouveau/tmr: ack interrupt before processing alarms
	drm/nouveau/tmr: fix corruption of the pending list when rescheduling an alarm
	drm/nouveau/tmr: avoid processing completed alarms when adding a new one
	drm/nouveau/tmr: handle races with hw when updating the next alarm time
	cdc-acm: fix possible invalid access when processing notification
	proc: Fix unbalanced hard link numbers
	of: fix sparse warning in of_pci_range_parser_one
	iio: dac: ad7303: fix channel description
	pid_ns: Sleep in TASK_INTERRUPTIBLE in zap_pid_ns_processes
	pid_ns: Fix race between setns'ed fork() and zap_pid_ns_processes()
	USB: serial: ftdi_sio: fix setting latency for unprivileged users
	USB: serial: ftdi_sio: add Olimex ARM-USB-TINY(H) PIDs
	ext4 crypto: don't let data integrity writebacks fail with ENOMEM
	ext4 crypto: fix some error handling
	net: qmi_wwan: Add SIMCom 7230E
	fscrypt: fix context consistency check when key(s) unavailable
	f2fs: check entire encrypted bigname when finding a dentry
	fscrypt: avoid collisions when presenting long encrypted filenames
	sched/fair: Do not announce throttled next buddy in dequeue_task_fair()
	sched/fair: Initialize throttle_count for new task-groups lazily
	usb: host: xhci-plat: propagate return value of platform_get_irq()
	xhci: apply PME_STUCK_QUIRK and MISSING_CAS quirk for Denverton
	usb: host: xhci-mem: allocate zeroed Scratchpad Buffer
	net: irda: irda-usb: fix firmware name on big-endian hosts
	usbvision: fix NULL-deref at probe
	mceusb: fix NULL-deref at probe
	ttusb2: limit messages to buffer size
	usb: musb: tusb6010_omap: Do not reset the other direction's packet size
	USB: iowarrior: fix info ioctl on big-endian hosts
	usb: serial: option: add Telit ME910 support
	USB: serial: qcserial: add more Lenovo EM74xx device IDs
	USB: serial: mct_u232: fix big-endian baud-rate handling
	USB: serial: io_ti: fix div-by-zero in set_termios
	USB: hub: fix SS hub-descriptor handling
	USB: hub: fix non-SS hub-descriptor handling
	ipx: call ipxitf_put() in ioctl error path
	iio: proximity: as3935: fix as3935_write
	ceph: fix recursion between ceph_set_acl() and __ceph_setattr()
	gspca: konica: add missing endpoint sanity check
	s5p-mfc: Fix unbalanced call to clock management
	dib0700: fix NULL-deref at probe
	zr364xx: enforce minimum size when reading header
	dvb-frontends/cxd2841er: define symbol_rate_min/max in T/C fe-ops
	cx231xx-audio: fix init error path
	cx231xx-audio: fix NULL-deref at probe
	cx231xx-cards: fix NULL-deref at probe
	powerpc/book3s/mce: Move add_taint() later in virtual mode
	powerpc/pseries: Fix of_node_put() underflow during DLPAR remove
	powerpc/64e: Fix hang when debugging programs with relocated kernel
	ARM: dts: at91: sama5d3_xplained: fix ADC vref
	ARM: dts: at91: sama5d3_xplained: not all ADC channels are available
	arm64: xchg: hazard against entire exchange variable
	arm64: uaccess: ensure extension of access_ok() addr
	arm64: documentation: document tagged pointer stack constraints
	xc2028: Fix use-after-free bug properly
	mm/huge_memory.c: respect FOLL_FORCE/FOLL_COW for thp
	staging: rtl8192e: fix 2 byte alignment of register BSSIDR.
	staging: rtl8192e: rtl92e_get_eeprom_size Fix read size of EPROM_CMD.
	iommu/vt-d: Flush the IOTLB to get rid of the initial kdump mappings
	metag/uaccess: Fix access_ok()
	metag/uaccess: Check access_ok in strncpy_from_user
	uwb: fix device quirk on big-endian hosts
	genirq: Fix chained interrupt data ordering
	osf_wait4(): fix infoleak
	tracing/kprobes: Enforce kprobes teardown after testing
	PCI: Fix pci_mmap_fits() for HAVE_PCI_RESOURCE_TO_USER platforms
	PCI: Freeze PME scan before suspending devices
	drm/edid: Add 10 bpc quirk for LGD 764 panel in HP zBook 17 G2
	nfsd: encoders mustn't use unitialized values in error cases
	drivers: char: mem: Check for address space wraparound with mmap()
	Linux 4.4.70

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

1 files changed, 11 insertions, 1 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 530e6427f823..47b469663822 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1269,6 +1269,16 @@ out_unlock:
 	return ret;
 }
 
+/*
+ * FOLL_FORCE can write to even unwritable pmd's, but only
+ * after we've gone through a COW cycle and they are dirty.
+ */
+static inline bool can_follow_write_pmd(pmd_t pmd, unsigned int flags)
+{
+	return pmd_write(pmd) ||
+	       ((flags & FOLL_FORCE) && (flags & FOLL_COW) && pmd_dirty(pmd));
+}
+
 struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
 				   unsigned long addr,
 				   pmd_t *pmd,
@@ -1279,7 +1289,7 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
 
 	assert_spin_locked(pmd_lockptr(mm, pmd));
 
-	if (flags & FOLL_WRITE && !pmd_write(*pmd))
+	if (flags & FOLL_WRITE && !can_follow_write_pmd(*pmd, flags))
 		goto out;
 
 	/* Avoid dumping huge zero page */