Merge 4.4.114 into android-4.4

Changes in 4.4.114
	x86/asm/32: Make sync_core() handle missing CPUID on all 32-bit kernels
	usbip: prevent vhci_hcd driver from leaking a socket pointer address
	usbip: Fix implicit fallthrough warning
	usbip: Fix potential format overflow in userspace tools
	x86/microcode/intel: Fix BDW late-loading revision check
	x86/cpu/intel: Introduce macros for Intel family numbers
	x86/retpoline: Fill RSB on context switch for affected CPUs
	sched/deadline: Use the revised wakeup rule for suspending constrained dl tasks
	can: af_can: can_rcv(): replace WARN_ONCE by pr_warn_once
	can: af_can: canfd_rcv(): replace WARN_ONCE by pr_warn_once
	PM / sleep: declare __tracedata symbols as char[] rather than char
	time: Avoid undefined behaviour in ktime_add_safe()
	timers: Plug locking race vs. timer migration
	Prevent timer value 0 for MWAITX
	drivers: base: cacheinfo: fix x86 with CONFIG_OF enabled
	drivers: base: cacheinfo: fix boot error message when acpi is enabled
	PCI: layerscape: Add "fsl,ls2085a-pcie" compatible ID
	PCI: layerscape: Fix MSG TLP drop setting
	mmc: sdhci-of-esdhc: add/remove some quirks according to vendor version
	fs/select: add vmalloc fallback for select(2)
	mm/mmap.c: do not blow on PROT_NONE MAP_FIXED holes in the stack
	hwpoison, memcg: forcibly uncharge LRU pages
	cma: fix calculation of aligned offset
	mm, page_alloc: fix potential false positive in __zone_watermark_ok
	ipc: msg, make msgrcv work with LONG_MIN
	x86/ioapic: Fix incorrect pointers in ioapic_setup_resources()
	ACPI / processor: Avoid reserving IO regions too early
	ACPI / scan: Prefer devices without _HID/_CID for _ADR matching
	ACPICA: Namespace: fix operand cache leak
	netfilter: x_tables: speed up jump target validation
	netfilter: arp_tables: fix invoking 32bit "iptable -P INPUT ACCEPT" failed in 64bit kernel
	netfilter: nf_dup_ipv6: set again FLOWI_FLAG_KNOWN_NH at flowi6_flags
	netfilter: nf_ct_expect: remove the redundant slash when policy name is empty
	netfilter: nfnetlink_queue: reject verdict request from different portid
	netfilter: restart search if moved to other chain
	netfilter: nf_conntrack_sip: extend request line validation
	netfilter: use fwmark_reflect in nf_send_reset
	netfilter: fix IS_ERR_VALUE usage
	netfilter: nfnetlink_cthelper: Add missing permission checks
	netfilter: xt_osf: Add missing permission checks
	ext2: Don't clear SGID when inheriting ACLs
	reiserfs: fix race in prealloc discard
	reiserfs: don't preallocate blocks for extended attributes
	reiserfs: Don't clear SGID when inheriting ACLs
	fs/fcntl: f_setown, avoid undefined behaviour
	scsi: libiscsi: fix shifting of DID_REQUEUE host byte
	Revert "module: Add retpoline tag to VERMAGIC"
	Input: trackpoint - force 3 buttons if 0 button is reported
	usb: usbip: Fix possible deadlocks reported by lockdep
	usbip: fix stub_rx: get_pipe() to validate endpoint number
	usbip: fix stub_rx: harden CMD_SUBMIT path to handle malicious input
	usbip: prevent leaking socket pointer address in messages
	um: link vmlinux with -no-pie
	vsyscall: Fix permissions for emulate mode with KAISER/PTI
	eventpoll.h: add missing epoll event masks
	x86/microcode/intel: Extend BDW late-loading further with LLC size check
	hrtimer: Reset hrtimer cpu base proper on CPU hotplug
	dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state
	ipv6: Fix getsockopt() for sockets with default IPV6_AUTOFLOWLABEL
	ipv6: fix udpv6 sendmsg crash caused by too small MTU
	ipv6: ip6_make_skb() needs to clear cork.base.dst
	lan78xx: Fix failure in USB Full Speed
	net: igmp: fix source address check for IGMPv3 reports
	tcp: __tcp_hdrlen() helper
	net: qdisc_pkt_len_init() should be more robust
	pppoe: take ->needed_headroom of lower device into account on xmit
	r8169: fix memory corruption on retrieval of hardware statistics.
	sctp: do not allow the v4 socket to bind a v4mapped v6 address
	sctp: return error if the asoc has been peeled off in sctp_wait_for_sndbuf
	vmxnet3: repair memory leak
	net: Allow neigh contructor functions ability to modify the primary_key
	ipv4: Make neigh lookup keys for loopback/point-to-point devices be INADDR_ANY
	flow_dissector: properly cap thoff field
	net: tcp: close sock if net namespace is exiting
	nfsd: auth: Fix gid sorting when rootsquash enabled
	Linux 4.4.114

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

1 files changed, 36 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 49d25ddf0e9f..8cacf62ec458 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -22,6 +22,7 @@
 #include <asm/alternative.h>
 #include <asm/pgtable.h>
 #include <asm/cacheflush.h>
+#include <asm/intel-family.h>
 
 static void __init spectre_v2_select_mitigation(void);
 
@@ -154,6 +155,23 @@ disable:
 	return SPECTRE_V2_CMD_NONE;
 }
 
+/* Check for Skylake-like CPUs (for RSB handling) */
+static bool __init is_skylake_era(void)
+{
+	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+	    boot_cpu_data.x86 == 6) {
+		switch (boot_cpu_data.x86_model) {
+		case INTEL_FAM6_SKYLAKE_MOBILE:
+		case INTEL_FAM6_SKYLAKE_DESKTOP:
+		case INTEL_FAM6_SKYLAKE_X:
+		case INTEL_FAM6_KABYLAKE_MOBILE:
+		case INTEL_FAM6_KABYLAKE_DESKTOP:
+			return true;
+		}
+	}
+	return false;
+}
+
 static void __init spectre_v2_select_mitigation(void)
 {
 	enum spectre_v2_mitigation_cmd cmd = spectre_v2_parse_cmdline();
@@ -212,6 +230,24 @@ retpoline_auto:
 
 	spectre_v2_enabled = mode;
 	pr_info("%s\n", spectre_v2_strings[mode]);
+
+	/*
+	 * If neither SMEP or KPTI are available, there is a risk of
+	 * hitting userspace addresses in the RSB after a context switch
+	 * from a shallow call stack to a deeper one. To prevent this fill
+	 * the entire RSB, even when using IBRS.
+	 *
+	 * Skylake era CPUs have a separate issue with *underflow* of the
+	 * RSB, when they will predict 'ret' targets from the generic BTB.
+	 * The proper mitigation for this is IBRS. If IBRS is not supported
+	 * or deactivated in favour of retpolines the RSB fill on context
+	 * switch is required.
+	 */
+	if ((!boot_cpu_has(X86_FEATURE_KAISER) &&
+	     !boot_cpu_has(X86_FEATURE_SMEP)) || is_skylake_era()) {
+		setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW);
+		pr_info("Filling RSB on context switch\n");
+	}
 }
 
 #undef pr_fmt