444 Commits

Author SHA1 Message Date
Greg Kroah-Hartman
0566f6529a Merge 4.4.255 into android-4.4-p
Changes in 4.4.255
	ACPI: sysfs: Prefer "compatible" modalias
	wext: fix NULL-ptr-dereference with cfg80211's lack of commit()
	net: usb: qmi_wwan: added support for Thales Cinterion PLSx3 modem family
	KVM: x86/pmu: Fix HW_REF_CPU_CYCLES event pseudo-encoding in intel_arch_events[]
	mt7601u: fix kernel crash unplugging the device
	mt7601u: fix rx buffer refcounting
	y2038: futex: Move compat implementation into futex.c
	futex: Move futex exit handling into futex code
	futex: Replace PF_EXITPIDONE with a state
	exit/exec: Seperate mm_release()
	futex: Split futex_mm_release() for exit/exec
	futex: Set task::futex_state to DEAD right after handling futex exit
	futex: Mark the begin of futex exit explicitly
	futex: Sanitize exit state handling
	futex: Provide state handling for exec() as well
	futex: Add mutex around futex exit
	futex: Provide distinct return value when owner is exiting
	futex: Prevent exit livelock
	ARM: imx: build suspend-imx6.S with arm instruction set
	netfilter: nft_dynset: add timeout extension to template
	xfrm: Fix oops in xfrm_replay_advance_bmp
	RDMA/cxgb4: Fix the reported max_recv_sge value
	mac80211: pause TX while changing interface type
	can: dev: prevent potential information leak in can_fill_info()
	iommu/vt-d: Gracefully handle DMAR units with no supported address widths
	iommu/vt-d: Don't dereference iommu_device if IOMMU_API is not built
	NFC: fix resource leak when target index is invalid
	NFC: fix possible resource leak
	Linux 4.4.255

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I33bac27670b3cd649e2c8c1ce42efff148f8f202
2021-02-03 23:41:54 +01:00
Thomas Gleixner
93d2eb4077 exit/exec: Seperate mm_release()
commit 4610ba7ad877fafc0a25a30c6c82015304120426 upstream.

mm_release() contains the futex exit handling. mm_release() is called from
do_exit()->exit_mm() and from exec()->exec_mm().

In the exit_mm() case PF_EXITING and the futex state is updated. In the
exec_mm() case these states are not touched.

As the futex exit code needs further protections against exit races, this
needs to be split into two functions.

Preparatory only, no functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.240518241@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-03 23:16:16 +01:00
Greg Kroah-Hartman
53454c3459 Merge 4.4.224 into android-4.4-p
Changes in 4.4.224
	USB: serial: qcserial: Add DW5816e support
	Revert "net: phy: Avoid polling PHY with PHY_IGNORE_INTERRUPTS"
	dp83640: reverse arguments to list_add_tail
	net/mlx4_core: Fix use of ENOSPC around mlx4_counter_alloc()
	sch_sfq: validate silly quantum values
	sch_choke: avoid potential panic in choke_reset()
	Revert "ACPI / video: Add force_native quirk for HP Pavilion dv6"
	enic: do not overwrite error code
	ipv6: fix cleanup ordering for ip6_mr failure
	binfmt_elf: move brk out of mmap when doing direct loader exec
	x86/apm: Don't access __preempt_count with zeroed fs
	Revert "IB/ipoib: Update broadcast object if PKey value was changed in index 0"
	USB: uas: add quirk for LaCie 2Big Quadra
	USB: serial: garmin_gps: add sanity checking for data length
	batman-adv: fix batadv_nc_random_weight_tq
	scripts/decodecode: fix trapping instruction formatting
	phy: micrel: Ensure interrupts are reenabled on resume
	binfmt_elf: Do not move brk for INTERP-less ET_EXEC
	ext4: add cond_resched() to ext4_protect_reserved_inode
	net: ipv6: add net argument to ip6_dst_lookup_flow
	net: ipv6_stub: use ip6_dst_lookup_flow instead of ip6_dst_lookup
	blktrace: Fix potential deadlock between delete & sysfs ops
	blktrace: fix unlocked access to init/start-stop/teardown
	blktrace: fix trace mutex deadlock
	blktrace: Protect q->blk_trace with RCU
	blktrace: fix dereference after null check
	ptp: do not explicitly set drvdata in ptp_clock_register()
	ptp: use is_visible method to hide unused attributes
	ptp: create "pins" together with the rest of attributes
	chardev: add helper function to register char devs with a struct device
	ptp: Fix pass zero to ERR_PTR() in ptp_clock_register
	ptp: fix the race between the release of ptp_clock and cdev
	ptp: free ptp device pin descriptors properly
	net: handle no dst on skb in icmp6_send
	net/sonic: Fix a resource leak in an error handling path in 'jazz_sonic_probe()'
	net: moxa: Fix a potential double 'free_irq()'
	drop_monitor: work around gcc-10 stringop-overflow warning
	scsi: sg: add sg_remove_request in sg_write
	spi: spi-dw: Add lock protect dw_spi rx/tx to prevent concurrent calls
	cifs: Check for timeout on Negotiate stage
	cifs: Fix a race condition with cifs_echo_request
	dmaengine: pch_dma.c: Avoid data race between probe and irq handler
	dmaengine: mmp_tdma: Reset channel error on release
	drm/qxl: lost qxl_bo_kunmap_atomic_page in qxl_image_init_helper()
	ipc/util.c: sysvipc_find_ipc() incorrectly updates position index
	net: openvswitch: fix csum updates for MPLS actions
	gre: do not keep the GRE header around in collect medata mode
	mm/memory_hotplug.c: fix overflow in test_pages_in_a_zone()
	scsi: qla2xxx: Avoid double completion of abort command
	i40e: avoid NVM acquire deadlock during NVM update
	net/mlx5: Fix driver load error flow when firmware is stuck
	netfilter: conntrack: avoid gcc-10 zero-length-bounds warning
	IB/mlx4: Test return value of calls to ib_get_cached_pkey
	pnp: Use list_for_each_entry() instead of open coding
	gcc-10 warnings: fix low-hanging fruit
	kbuild: compute false-positive -Wmaybe-uninitialized cases in Kconfig
	Stop the ad-hoc games with -Wno-maybe-initialized
	gcc-10: disable 'zero-length-bounds' warning for now
	gcc-10: disable 'array-bounds' warning for now
	gcc-10: disable 'stringop-overflow' warning for now
	gcc-10: disable 'restrict' warning for now
	block: defer timeouts to a workqueue
	blk-mq: Allow timeouts to run while queue is freezing
	blk-mq: sync the update nr_hw_queues with blk_mq_queue_tag_busy_iter
	blk-mq: Allow blocking queue tag iter callbacks
	x86/paravirt: Remove the unused irq_enable_sysexit pv op
	gcc-10: avoid shadowing standard library 'free()' in crypto
	net: fix a potential recursive NETDEV_FEAT_CHANGE
	net: ipv4: really enforce backoff for redirects
	netlabel: cope with NULL catmap
	ALSA: hda/realtek - Limit int mic boost for Thinkpad T530
	ALSA: rawmidi: Fix racy buffer resize under concurrent accesses
	ALSA: rawmidi: Initialize allocated buffers
	USB: gadget: fix illegal array access in binding with UDC
	ARM: dts: imx27-phytec-phycard-s-rdk: Fix the I2C1 pinctrl entries
	x86: Fix early boot crash on gcc-10, third try
	exec: Move would_dump into flush_old_exec
	usb: gadget: net2272: Fix a memory leak in an error handling path in 'net2272_plat_probe()'
	usb: gadget: audio: Fix a missing error return value in audio_bind()
	usb: gadget: legacy: fix error return code in gncm_bind()
	usb: gadget: legacy: fix error return code in cdc_bind()
	Revert "ALSA: hda/realtek: Fix pop noise on ALC225"
	ARM: dts: r8a7740: Add missing extal2 to CPG node
	KVM: x86: Fix off-by-one error in kvm_vcpu_ioctl_x86_setup_mce
	Makefile: disallow data races on gcc-10 as well
	scsi: iscsi: Fix a potential deadlock in the timeout handler
	Linux 4.4.224

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I384313d39dead8b0babb144803269033f4aacc53
2020-05-20 11:53:50 +02:00
Eric W. Biederman
84cd70984e exec: Move would_dump into flush_old_exec
commit f87d1c9559164294040e58f5e3b74a162bf7c6e8 upstream.

I goofed when I added mm->user_ns support to would_dump.  I missed the
fact that in the case of binfmt_loader, binfmt_em86, binfmt_misc, and
binfmt_script bprm->file is reassigned.  Which made the move of
would_dump from setup_new_exec to __do_execve_file before exec_binprm
incorrect as it can result in would_dump running on the script instead
of the interpreter of the script.

The net result is that the code stopped making unreadable interpreters
undumpable.  Which allows them to be ptraced and written to disk
without special permissions.  Oops.

The move was necessary because the call in set_new_exec was after
bprm->mm was no longer valid.

To correct this mistake move the misplaced would_dump from
__do_execve_file into flos_old_exec, before exec_mmap is called.

I tested and confirmed that without this fix I can attach with gdb to
a script with an unreadable interpreter, and with this fix I can not.

Cc: stable@vger.kernel.org
Fixes: f84df2a6f268 ("exec: Ensure mm->user_ns contains the execed files")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:11:54 +02:00
Greg Kroah-Hartman
d590d674fc Merge 4.4.220 into android-4.4-p
Changes in 4.4.220
	bus: sunxi-rsb: Return correct data when mixing 16-bit and 8-bit reads
	net: vxge: fix wrong __VA_ARGS__ usage
	qlcnic: Fix bad kzalloc null test
	i2c: st: fix missing struct parameter description
	irqchip/versatile-fpga: Handle chained IRQs properly
	selftests/x86/ptrace_syscall_32: Fix no-vDSO segfault
	libata: Remove extra scsi_host_put() in ata_scsi_add_hosts()
	gfs2: Don't demote a glock until its revokes are written
	x86/boot: Use unsigned comparison for addresses
	locking/lockdep: Avoid recursion in lockdep_count_{for,back}ward_deps()
	btrfs: remove a BUG_ON() from merge_reloc_roots()
	btrfs: track reloc roots based on their commit root bytenr
	misc: rtsx: set correct pcr_ops for rts522A
	ASoC: fix regwmask
	ASoC: dapm: connect virtual mux with default value
	ASoC: dpcm: allow start or stop during pause for backend
	ASoC: topology: use name_prefix for new kcontrol
	usb: gadget: f_fs: Fix use after free issue as part of queue failure
	usb: gadget: composite: Inform controller driver of self-powered
	ALSA: usb-audio: Add mixer workaround for TRX40 and co
	ALSA: hda: Add driver blacklist
	ALSA: hda: Fix potential access overflow in beep helper
	ALSA: ice1724: Fix invalid access for enumerated ctl items
	ALSA: pcm: oss: Fix regression by buffer overflow fix
	acpi/x86: ignore unspecified bit positions in the ACPI global lock field
	thermal: devfreq_cooling: inline all stubs for CONFIG_DEVFREQ_THERMAL=n
	KEYS: reaching the keys quotas correctly
	irqchip/versatile-fpga: Apply clear-mask earlier
	MIPS: OCTEON: irq: Fix potential NULL pointer dereference
	ath9k: Handle txpower changes even when TPC is disabled
	signal: Extend exec_id to 64bits
	x86/entry/32: Add missing ASM_CLAC to general_protection entry
	KVM: x86: Allocate new rmap and large page tracking when moving memslot
	crypto: mxs-dcp - fix scatterlist linearization for hash
	futex: futex_wake_op, do not fail on invalid op
	xen-netfront: Rework the fix for Rx stall during OOM and network stress
	ALSA: hda: Initialize power_state field properly
	Btrfs: incremental send, fix invalid memory access
	IB/ipoib: Fix lockdep issue found on ipoib_ib_dev_heavy_flush
	scsi: zfcp: fix missing erp_lock in port recovery trigger for point-to-point
	arm64: armv8_deprecated: Fix undef_hook mask for thumb setend
	ext4: fix a data race at inode->i_blocks
	ocfs2: no need try to truncate file beyond i_size
	s390/diag: fix display of diagnose call statistics
	Input: i8042 - add Acer Aspire 5738z to nomux list
	kmod: make request_module() return an error when autoloading is disabled
	hfsplus: fix crash and filesystem corruption when deleting files
	libata: Return correct status in sata_pmp_eh_recover_pm() when ATA_DFLAG_DETACH is set
	powerpc/64/tm: Don't let userspace set regs->trap via sigreturn
	Btrfs: fix crash during unmount due to race with delayed inode workers
	drm/dp_mst: Fix clearing payload state on topology disable
	ipmi: fix hung processes in __get_guid()
	powerpc/fsl_booke: Avoid creating duplicate tlb1 entry
	misc: echo: Remove unnecessary parentheses and simplify check for zero
	mfd: dln2: Fix sanity checking for endpoints
	net: ipv4: devinet: Fix crash when add/del multicast IP with autojoin
	net: ipv6: do not consider routes via gateways for anycast address check
	scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic
	jbd2: improve comments about freeing data buffers whose page mapping is NULL
	ext4: fix incorrect group count in ext4_fill_super error message
	ext4: fix incorrect inodes per group in error message
	ASoC: Intel: mrfld: fix incorrect check on p->sink
	ASoC: Intel: mrfld: return error codes when an error occurs
	ALSA: usb-audio: Don't override ignore_ctl_error value from the map
	mac80211_hwsim: Use kstrndup() in place of kasprintf()
	ext4: do not zeroout extents beyond i_disksize
	dm flakey: check for null arg_name in parse_features()
	kvm: x86: Host feature SSBD doesn't imply guest feature SPEC_CTRL_SSBD
	x86/mitigations: Clear CPU buffers on the SYSCALL fast path
	tracing: Fix the race between registering 'snapshot' event trigger and triggering 'snapshot' operation
	scsi: sg: add sg_remove_request in sg_common_write
	ALSA: hda: Don't release card at firmware loading error
	video: fbdev: sis: Remove unnecessary parentheses and commented code
	drm: NULL pointer dereference [null-pointer-deref] (CWE 476) problem
	wil6210: increase firmware ready timeout
	wil6210: fix temperature debugfs
	scsi: ufs: ufs-qcom: remove broken hci version quirk
	wil6210: rate limit wil_rx_refill error
	rtc: pm8xxx: Fix issue in RTC write path
	soc: qcom: smem: Use le32_to_cpu for comparison
	of: fix missing kobject init for !SYSFS && OF_DYNAMIC config
	of: unittest: kmemleak in of_unittest_platform_populate()
	clk: at91: usb: continue if clk_hw_round_rate() return zero
	clk: tegra: Fix Tegra PMC clock out parents
	NFS: direct.c: Fix memory leak of dreq when nfs_get_lock_context fails
	ext4: do not commit super on read-only bdev
	percpu_counter: fix a data race at vm_committed_as
	compiler.h: fix error in BUILD_BUG_ON() reporting
	NFS: Fix memory leaks in nfs_pageio_stop_mirroring()
	ext2: fix empty body warnings when -Wextra is used
	iommu/amd: Fix the configuration of GCR3 table root pointer
	fbdev: potential information leak in do_fb_ioctl()
	tty: evh_bytechan: Fix out of bounds accesses
	locktorture: Print ratio of acquisitions, not failures
	mtd: lpddr: Fix a double free in probe()
	mtd: phram: fix a double free issue in error path
	x86/CPU: Add native CPUID variants returning a single datum
	x86/microcode/intel: replace sync_core() with native_cpuid_reg(eax)
	x86/vdso: Fix lsl operand order
	Linux 4.4.220

Change-Id: Ic931642c95ad95eb2755c3c20f6802e04283e68b
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2020-04-24 08:33:15 +02:00
Eric W. Biederman
6b9e27da8f signal: Extend exec_id to 64bits
commit d1e7fd6462ca9fc76650fbe6ca800e35b24267da upstream.

Replace the 32bit exec_id with a 64bit exec_id to make it impossible
to wrap the exec_id counter.  With care an attacker can cause exec_id
wrap and send arbitrary signals to a newly exec'd parent.  This
bypasses the signal sending checks if the parent changes their
credentials during exec.

The severity of this problem can been seen that in my limited testing
of a 32bit exec_id it can take as little as 19s to exec 65536 times.
Which means that it can take as little as 14 days to wrap a 32bit
exec_id.  Adam Zabrocki has succeeded wrapping the self_exe_id in 7
days.  Even my slower timing is in the uptime of a typical server.
Which means self_exec_id is simply a speed bump today, and if exec
gets noticably faster self_exec_id won't even be a speed bump.

Extending self_exec_id to 64bits introduces a problem on 32bit
architectures where reading self_exec_id is no longer atomic and can
take two read instructions.  Which means that is is possible to hit
a window where the read value of exec_id does not match the written
value.  So with very lucky timing after this change this still
remains expoiltable.

I have updated the update of exec_id on exec to use WRITE_ONCE
and the read of exec_id in do_notify_parent to use READ_ONCE
to make it clear that there is no locking between these two
locations.

Link: https://lore.kernel.org/kernel-hardening/20200324215049.GA3710@pi3.com.pl
Fixes: 2.3.23pre2
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:57:12 +02:00
Greg Kroah-Hartman
ebf4d7ea8d Merge 4.4.187 into android-4.4-p
Changes in 4.4.187
	MIPS: ath79: fix ar933x uart parity mode
	MIPS: fix build on non-linux hosts
	dmaengine: imx-sdma: fix use-after-free on probe error path
	ath10k: Do not send probe response template for mesh
	ath9k: Check for errors when reading SREV register
	ath6kl: add some bounds checking
	ath: DFS JP domain W56 fixed pulse type 3 RADAR detection
	batman-adv: fix for leaked TVLV handler.
	media: dvb: usb: fix use after free in dvb_usb_device_exit
	crypto: talitos - fix skcipher failure due to wrong output IV
	media: marvell-ccic: fix DMA s/g desc number calculation
	media: vpss: fix a potential NULL pointer dereference
	net: stmmac: dwmac1000: Clear unused address entries
	signal/pid_namespace: Fix reboot_pid_ns to use send_sig not force_sig
	af_key: fix leaks in key_pol_get_resp and dump_sp.
	xfrm: Fix xfrm sel prefix length validation
	media: staging: media: davinci_vpfe: - Fix for memory leak if decoder initialization fails.
	net: phy: Check against net_device being NULL
	tua6100: Avoid build warnings.
	locking/lockdep: Fix merging of hlocks with non-zero references
	media: wl128x: Fix some error handling in fm_v4l2_init_video_device()
	cpupower : frequency-set -r option misses the last cpu in related cpu list
	net: fec: Do not use netdev messages too early
	net: axienet: Fix race condition causing TX hang
	s390/qdio: handle PENDING state for QEBSM devices
	perf test 6: Fix missing kvm module load for s390
	gpio: omap: fix lack of irqstatus_raw0 for OMAP4
	gpio: omap: ensure irq is enabled before wakeup
	regmap: fix bulk writes on paged registers
	bpf: silence warning messages in core
	rcu: Force inlining of rcu_read_lock()
	xfrm: fix sa selector validation
	perf evsel: Make perf_evsel__name() accept a NULL argument
	vhost_net: disable zerocopy by default
	EDAC/sysfs: Fix memory leak when creating a csrow object
	media: i2c: fix warning same module names
	ntp: Limit TAI-UTC offset
	timer_list: Guard procfs specific code
	acpi/arm64: ignore 5.1 FADTs that are reported as 5.0
	media: coda: fix mpeg2 sequence number handling
	media: coda: increment sequence offset for the last returned frame
	mt7601u: do not schedule rx_tasklet when the device has been disconnected
	x86/build: Add 'set -e' to mkcapflags.sh to delete broken capflags.c
	mt7601u: fix possible memory leak when the device is disconnected
	ath10k: fix PCIE device wake up failed
	rslib: Fix decoding of shortened codes
	rslib: Fix handling of of caller provided syndrome
	ixgbe: Check DDM existence in transceiver before access
	EDAC: Fix global-out-of-bounds write when setting edac_mc_poll_msec
	bcache: check c->gc_thread by IS_ERR_OR_NULL in cache_set_flush()
	Bluetooth: hci_bcsp: Fix memory leak in rx_skb
	Bluetooth: 6lowpan: search for destination address in all peers
	Bluetooth: Check state in l2cap_disconnect_rsp
	Bluetooth: validate BLE connection interval updates
	crypto: ghash - fix unaligned memory access in ghash_setkey()
	crypto: arm64/sha1-ce - correct digest for empty data in finup
	crypto: arm64/sha2-ce - correct digest for empty data in finup
	Input: gtco - bounds check collection indent level
	regulator: s2mps11: Fix buck7 and buck8 wrong voltages
	tracing/snapshot: Resize spare buffer if size changed
	NFSv4: Handle the special Linux file open access mode
	lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE
	ALSA: seq: Break too long mutex context in the write loop
	media: v4l2: Test type instead of cfg->type in v4l2_ctrl_new_custom()
	media: coda: Remove unbalanced and unneeded mutex unlock
	KVM: x86/vPMU: refine kvm_pmu err msg when event creation failed
	drm/nouveau/i2c: Enable i2c pads & busses during preinit
	padata: use smp_mb in padata_reorder to avoid orphaned padata jobs
	9p/virtio: Add cleanup path in p9_virtio_init
	PCI: Do not poll for PME if the device is in D3cold
	take floppy compat ioctls to sodding floppy.c
	floppy: fix div-by-zero in setup_format_params
	floppy: fix out-of-bounds read in next_valid_format
	floppy: fix invalid pointer dereference in drive_name
	floppy: fix out-of-bounds read in copy_buffer
	coda: pass the host file in vma->vm_file on mmap
	gpu: ipu-v3: ipu-ic: Fix saturation bit offset in TPMEM
	parisc: Fix kernel panic due invalid values in IAOQ0 or IAOQ1
	powerpc/32s: fix suspend/resume when IBATs 4-7 are used
	powerpc/watchpoint: Restore NV GPRs while returning from exception
	eCryptfs: fix a couple type promotion bugs
	intel_th: msu: Fix single mode with disabled IOMMU
	Bluetooth: Add SMP workaround Microsoft Surface Precision Mouse bug
	usb: Handle USB3 remote wakeup for LPM enabled devices correctly
	dm bufio: fix deadlock with loop device
	bnx2x: Prevent load reordering in tx completion processing
	caif-hsi: fix possible deadlock in cfhsi_exit_module()
	ipv4: don't set IPv6 only flags to IPv4 addresses
	net: bcmgenet: use promisc for unsupported filters
	net: neigh: fix multiple neigh timer scheduling
	nfc: fix potential illegal memory access
	sky2: Disable MSI on ASUS P6T
	netrom: fix a memory leak in nr_rx_frame()
	netrom: hold sock when setting skb->destructor
	tcp: Reset bytes_acked and bytes_received when disconnecting
	bonding: validate ip header before check IPPROTO_IGMP
	net: bridge: mcast: fix stale nsrcs pointer in igmp3/mld2 report handling
	net: bridge: mcast: fix stale ipv6 hdr pointer when handling v6 query
	net: bridge: stp: don't cache eth dest pointer before skb pull
	elevator: fix truncation of icq_cache_name
	NFSv4: Fix open create exclusive when the server reboots
	nfsd: increase DRC cache limit
	nfsd: give out fewer session slots as limit approaches
	nfsd: fix performance-limiting session calculation
	nfsd: Fix overflow causing non-working mounts on 1 TB machines
	drm/panel: simple: Fix panel_simple_dsi_probe
	usb: core: hub: Disable hub-initiated U1/U2
	tty: max310x: Fix invalid baudrate divisors calculator
	pinctrl: rockchip: fix leaked of_node references
	tty: serial: cpm_uart - fix init when SMC is relocated
	memstick: Fix error cleanup path of memstick_init
	tty/serial: digicolor: Fix digicolor-usart already registered warning
	tty: serial: msm_serial: avoid system lockup condition
	drm/virtio: Add memory barriers for capset cache.
	phy: renesas: rcar-gen2: Fix memory leak at error paths
	usb: gadget: Zero ffs_io_data
	powerpc/pci/of: Fix OF flags parsing for 64bit BARs
	PCI: sysfs: Ignore lockdep for remove attribute
	iio: iio-utils: Fix possible incorrect mask calculation
	recordmcount: Fix spurious mcount entries on powerpc
	mfd: core: Set fwnode for created devices
	mfd: arizona: Fix undefined behavior
	um: Silence lockdep complaint about mmap_sem
	powerpc/4xx/uic: clear pending interrupt after irq type/pol change
	serial: sh-sci: Fix TX DMA buffer flushing and workqueue races
	kallsyms: exclude kasan local symbols on s390
	perf test mmap-thread-lookup: Initialize variable to suppress memory sanitizer warning
	f2fs: avoid out-of-range memory access
	mailbox: handle failed named mailbox channel request
	powerpc/eeh: Handle hugepages in ioremap space
	sh: prevent warnings when using iounmap
	mm/kmemleak.c: fix check for softirq context
	9p: pass the correct prototype to read_cache_page
	mm/mmu_notifier: use hlist_add_head_rcu()
	locking/lockdep: Fix lock used or unused stats error
	locking/lockdep: Hide unused 'class' variable
	usb: wusbcore: fix unbalanced get/put cluster_id
	usb: pci-quirks: Correct AMD PLL quirk detection
	x86/sysfb_efi: Add quirks for some devices with swapped width and height
	x86/speculation/mds: Apply more accurate check on hypervisor platform
	hpet: Fix division by zero in hpet_time_div()
	ALSA: line6: Fix wrong altsetting for LINE6_PODHD500_1
	ALSA: hda - Add a conexant codec entry to let mute led work
	powerpc/tm: Fix oops on sigreturn on systems without TM
	access: avoid the RCU grace period for the temporary subjective credentials
	vmstat: Remove BUG_ON from vmstat_update
	mm, vmstat: make quiet_vmstat lighter
	ipv6: check sk sk_type and protocol early in ip_mroute_set/getsockopt
	tcp: reset sk_send_head in tcp_write_queue_purge
	ISDN: hfcsusb: checking idx of ep configuration
	media: cpia2_usb: first wake up, then free in disconnect
	media: radio-raremono: change devm_k*alloc to k*alloc
	Bluetooth: hci_uart: check for missing tty operations
	sched/fair: Don't free p->numa_faults with concurrent readers
	drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
	ceph: hold i_ceph_lock when removing caps for freeing inode
	Linux 4.4.187

Change-Id: I6086b23376cdf9f6a905f727fb07175a7ebdd356
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2019-08-04 09:53:45 +02:00
Jann Horn
da358f365d sched/fair: Don't free p->numa_faults with concurrent readers
commit 16d51a590a8ce3befb1308e0e7ab77f3b661af33 upstream.

When going through execve(), zero out the NUMA fault statistics instead of
freeing them.

During execve, the task is reachable through procfs and the scheduler. A
concurrent /proc/*/sched reader can read data from a freed ->numa_faults
allocation (confirmed by KASAN) and write it back to userspace.
I believe that it would also be possible for a use-after-free read to occur
through a race between a NUMA fault and execve(): task_numa_fault() can
lead to task_numa_compare(), which invokes task_weight() on the currently
running task of a different CPU.

Another way to fix this would be to make ->numa_faults RCU-managed or add
extra locking, but it seems easier to wipe the NUMA fault statistics on
execve.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Fixes: 82727018b0 ("sched/numa: Call task_numa_free() from do_execve()")
Link: https://lkml.kernel.org/r/20190716152047.14424-1-jannh@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-04 09:35:02 +02:00
Greg Kroah-Hartman
4074ea50e0 Merge 4.4.168 into android-4.4-p
Changes in 4.4.168
	ipv6: Check available headroom in ip6_xmit() even without options
	net: 8139cp: fix a BUG triggered by changing mtu with network traffic
	net: phy: don't allow __set_phy_supported to add unsupported modes
	net: Prevent invalid access to skb->prev in __qdisc_drop_all
	rtnetlink: ndo_dflt_fdb_dump() only work for ARPHRD_ETHER devices
	tcp: fix NULL ref in tail loss probe
	tun: forbid iface creation with rtnl ops
	neighbour: Avoid writing before skb->head in neigh_hh_output()
	ARM: OMAP2+: prm44xx: Fix section annotation on omap44xx_prm_enable_io_wakeup
	ARM: OMAP1: ams-delta: Fix possible use of uninitialized field
	sysv: return 'err' instead of 0 in __sysv_write_inode
	s390/cpum_cf: Reject request for sampling in event initialization
	hwmon: (ina2xx) Fix current value calculation
	ASoC: dapm: Recalculate audio map forcely when card instantiated
	hwmon: (w83795) temp4_type has writable permission
	Btrfs: send, fix infinite loop due to directory rename dependencies
	ASoC: omap-mcpdm: Add pm_qos handling to avoid under/overruns with CPU_IDLE
	ASoC: omap-dmic: Add pm_qos handling to avoid overruns with CPU_IDLE
	exportfs: do not read dentry after free
	bpf: fix check of allowed specifiers in bpf_trace_printk
	USB: omap_udc: use devm_request_irq()
	USB: omap_udc: fix crashes on probe error and module removal
	USB: omap_udc: fix omap_udc_start() on 15xx machines
	USB: omap_udc: fix USB gadget functionality on Palm Tungsten E
	KVM: x86: fix empty-body warnings
	net: thunderx: fix NULL pointer dereference in nic_remove
	ixgbe: recognize 1000BaseLX SFP modules as 1Gbps
	net: hisilicon: remove unexpected free_netdev
	drm/ast: fixed reading monitor EDID not stable issue
	xen: xlate_mmu: add missing header to fix 'W=1' warning
	fscache: fix race between enablement and dropping of object
	fscache, cachefiles: remove redundant variable 'cache'
	ocfs2: fix deadlock caused by ocfs2_defrag_extent()
	hfs: do not free node before using
	hfsplus: do not free node before using
	debugobjects: avoid recursive calls with kmemleak
	ocfs2: fix potential use after free
	pstore: Convert console write to use ->write_buf
	ALSA: pcm: remove SNDRV_PCM_IOCTL1_INFO internal command
	KVM: nVMX: fix msr bitmaps to prevent L2 from accessing L0 x2APIC
	KVM: nVMX: mark vmcs12 pages dirty on L2 exit
	KVM: nVMX: Eliminate vmcs02 pool
	KVM: VMX: introduce alloc_loaded_vmcs
	KVM: VMX: make MSR bitmaps per-VCPU
	KVM/x86: Add IBPB support
	KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES
	KVM/VMX: Allow direct access to MSR_IA32_SPEC_CTRL
	KVM/SVM: Allow direct access to MSR_IA32_SPEC_CTRL
	KVM/x86: Remove indirect MSR op calls from SPEC_CTRL
	x86: reorganize SMAP handling in user space accesses
	x86: fix SMAP in 32-bit environments
	x86: Introduce __uaccess_begin_nospec() and uaccess_try_nospec
	x86/usercopy: Replace open coded stac/clac with __uaccess_{begin, end}
	x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec
	x86/bugs, KVM: Support the combination of guest and host IBRS
	x86/KVM/VMX: Expose SPEC_CTRL Bit(2) to the guest
	KVM: SVM: Move spec control call after restore of GS
	x86/bugs, KVM: Extend speculation control for VIRT_SPEC_CTRL
	x86/speculation: Use synthetic bits for IBRS/IBPB/STIBP
	KVM: SVM: Implement VIRT_SPEC_CTRL support for SSBD
	bpf: support 8-byte metafield access
	bpf/verifier: Add spi variable to check_stack_write()
	bpf/verifier: Pass instruction index to check_mem_access() and check_xadd()
	bpf: Prevent memory disambiguation attack
	wil6210: missing length check in wmi_set_ie
	posix-timers: Sanitize overrun handling
	mm/hugetlb.c: don't call region_abort if region_chg fails
	hugetlbfs: fix offset overflow in hugetlbfs mmap
	hugetlbfs: check for pgoff value overflow
	hugetlbfs: fix bug in pgoff overflow checking
	swiotlb: clean up reporting
	sr: pass down correctly sized SCSI sense buffer
	mm: remove write/force parameters from __get_user_pages_locked()
	mm: remove write/force parameters from __get_user_pages_unlocked()
	mm/nommu.c: Switch __get_user_pages_unlocked() to use __get_user_pages()
	mm: replace get_user_pages_unlocked() write/force parameters with gup_flags
	mm: replace get_user_pages_locked() write/force parameters with gup_flags
	mm: replace get_vaddr_frames() write/force parameters with gup_flags
	mm: replace get_user_pages() write/force parameters with gup_flags
	mm: replace __access_remote_vm() write parameter with gup_flags
	mm: replace access_remote_vm() write parameter with gup_flags
	proc: don't use FOLL_FORCE for reading cmdline and environment
	proc: do not access cmdline nor environ from file-backed areas
	media: dvb-frontends: fix i2c access helpers for KASAN
	matroxfb: fix size of memcpy
	staging: speakup: Replace strncpy with memcpy
	rocker: fix rocker_tlv_put_* functions for KASAN
	selftests: Move networking/timestamping from Documentation
	Linux 4.4.168

Change-Id: Icd04a723739ae5e38258a2f6b0aee875f306a0bc
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2018-12-19 19:22:06 +01:00
Lorenzo Stoakes
8e50b8b07f mm: replace get_user_pages() write/force parameters with gup_flags
commit 768ae309a96103ed02eb1e111e838c87854d8b51 upstream.

This removes the 'write' and 'force' from get_user_pages() and replaces
them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers
as use of this flag can result in surprising behaviour (and hence bugs)
within the mm subsystem.

Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 4.4:
 - Drop changes in rapidio, vchiq, goldfish
 - Keep the "write" variable in amdgpu_ttm_tt_pin_userptr() as it's still
   needed
 - Also update calls from various other places that now use
   get_user_pages_remote() upstream, which were updated there by commit
   9beae1ea8930 "mm: replace get_user_pages_remote() write/force ..."
 - Also update calls from hfi1 and ipath
 - Adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-17 21:55:16 +01:00
Greg Kroah-Hartman
8fc3f01965 Merge 4.4.167 into android-4.4-p
Changes in 4.4.167
	media: em28xx: Fix use-after-free when disconnecting
	Revert "wlcore: Add missing PM call for wlcore_cmd_wait_for_event_or_timeout()"
	rapidio/rionet: do not free skb before reading its length
	s390/qeth: fix length check in SNMP processing
	usbnet: ipheth: fix potential recvmsg bug and recvmsg bug 2
	kvm: mmu: Fix race in emulated page table writes
	xtensa: enable coprocessors that are being flushed
	xtensa: fix coprocessor context offset definitions
	Btrfs: ensure path name is null terminated at btrfs_control_ioctl
	ALSA: wss: Fix invalid snd_free_pages() at error path
	ALSA: ac97: Fix incorrect bit shift at AC97-SPSA control write
	ALSA: control: Fix race between adding and removing a user element
	ALSA: sparc: Fix invalid snd_free_pages() at error path
	ext2: fix potential use after free
	dmaengine: at_hdmac: fix memory leak in at_dma_xlate()
	dmaengine: at_hdmac: fix module unloading
	btrfs: release metadata before running delayed refs
	USB: usb-storage: Add new IDs to ums-realtek
	usb: core: quirks: add RESET_RESUME quirk for Cherry G230 Stream series
	misc: mic/scif: fix copy-paste error in scif_create_remote_lookup
	Kbuild: suppress packed-not-aligned warning for default setting only
	exec: avoid gcc-8 warning for get_task_comm
	disable stringop truncation warnings for now
	kobject: Replace strncpy with memcpy
	unifdef: use memcpy instead of strncpy
	kernfs: Replace strncpy with memcpy
	ip_tunnel: Fix name string concatenate in __ip_tunnel_create()
	drm: gma500: fix logic error
	scsi: bfa: convert to strlcpy/strlcat
	staging: rts5208: fix gcc-8 logic error warning
	kdb: use memmove instead of overlapping memcpy
	iser: set sector for ambiguous mr status errors
	uprobes: Fix handle_swbp() vs. unregister() + register() race once more
	MIPS: ralink: Fix mt7620 nd_sd pinmux
	mips: fix mips_get_syscall_arg o32 check
	drm/ast: Fix incorrect free on ioregs
	scsi: scsi_devinfo: cleanly zero-pad devinfo strings
	ALSA: trident: Suppress gcc string warning
	scsi: csiostor: Avoid content leaks and casts
	kgdboc: Fix restrict error
	kgdboc: Fix warning with module build
	leds: call led_pwm_set() in leds-pwm to enforce default LED_OFF
	leds: turn off the LED and wait for completion on unregistering LED class device
	leds: leds-gpio: Fix return value check in create_gpio_led()
	Input: xpad - quirk all PDP Xbox One gamepads
	Input: matrix_keypad - check for errors from of_get_named_gpio()
	Input: elan_i2c - add ELAN0620 to the ACPI table
	Input: elan_i2c - add ACPI ID for Lenovo IdeaPad 330-15ARR
	Input: elan_i2c - add support for ELAN0621 touchpad
	btrfs: Always try all copies when reading extent buffers
	Btrfs: fix use-after-free when dumping free space
	ARC: change defconfig defaults to ARCv2
	arc: [devboards] Add support of NFSv3 ACL
	mm: cleancache: fix corruption on missed inode invalidation
	mm: mlock: avoid increase mm->locked_vm on mlock() when already mlock2(,MLOCK_ONFAULT)
	usb: gadget: dummy: fix nonsensical comparisons
	iommu/vt-d: Fix NULL pointer dereference in prq_event_thread()
	iommu/ipmmu-vmsa: Fix crash on early domain free
	can: rcar_can: Fix erroneous registration
	batman-adv: Expand merged fragment buffer for full packet
	bnx2x: Assign unique DMAE channel number for FW DMAE transactions.
	qed: Fix PTT leak in qed_drain()
	qed: Fix reading wrong value in loop condition
	net/mlx4_core: Zero out lkey field in SW2HW_MPT fw command
	net/mlx4_core: Fix uninitialized variable compilation warning
	net/mlx4: Fix UBSAN warning of signed integer overflow
	net: faraday: ftmac100: remove netif_running(netdev) check before disabling interrupts
	iommu/vt-d: Use memunmap to free memremap
	net: amd: add missing of_node_put()
	usb: quirk: add no-LPM quirk on SanDisk Ultra Flair device
	usb: appledisplay: Add 27" Apple Cinema Display
	USB: check usb_get_extra_descriptor for proper size
	ALSA: usb-audio: Fix UAF decrement if card has no live interfaces in card.c
	ALSA: hda: Add support for AMD Stoney Ridge
	ALSA: pcm: Fix starvation on down_write_nonblock()
	ALSA: pcm: Call snd_pcm_unlink() conditionally at closing
	ALSA: pcm: Fix interval evaluation with openmin/max
	virtio/s390: avoid race on vcdev->config
	virtio/s390: fix race in ccw_io_helper()
	SUNRPC: Fix leak of krb5p encode pages
	xhci: Prevent U1/U2 link pm states if exit latency is too long
	Staging: lustre: remove two build warnings
	cifs: Fix separator when building path from dentry
	tty: serial: 8250_mtk: always resume the device in probe.
	kgdboc: fix KASAN global-out-of-bounds bug in param_set_kgdboc_var()
	mac80211_hwsim: Timer should be initialized before device registered
	mac80211: Clear beacon_int in ieee80211_do_stop
	mac80211: ignore tx status for PS stations in ieee80211_tx_status_ext
	mac80211: fix reordering of buffered broadcast packets
	mac80211: ignore NullFunc frames in the duplicate detection
	Linux 4.4.167

Change-Id: I67673edf3244cb17523bfb13f256d5b3ddd1bcba
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2018-12-13 09:44:10 +01:00
Arnd Bergmann
2ac36cc66c exec: avoid gcc-8 warning for get_task_comm
commit 3756f6401c302617c5e091081ca4d26ab604bec5 upstream.

gcc-8 warns about using strncpy() with the source size as the limit:

  fs/exec.c:1223:32: error: argument to 'sizeof' in 'strncpy' call is the same expression as the source; did you mean to use the size of the destination? [-Werror=sizeof-pointer-memaccess]

This is indeed slightly suspicious, as it protects us from source
arguments without NUL-termination, but does not guarantee that the
destination is terminated.

This keeps the strncpy() to ensure we have properly padded target
buffer, but ensures that we use the correct length, by passing the
actual length of the destination buffer as well as adding a build-time
check to ensure it is exactly TASK_COMM_LEN.

There are only 23 callsites which I all reviewed to ensure this is
currently the case.  We could get away with doing only the check or
passing the right length, but it doesn't hurt to do both.

Link: http://lkml.kernel.org/r/20171205151724.1764896-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Kees Cook <keescook@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Aleksa Sarai <asarai@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-13 09:21:28 +01:00
Greg Kroah-Hartman
59ff2e15be Merge 4.4.78 into android-4.4
Changes in 4.4.78
	net_sched: fix error recovery at qdisc creation
	net: sched: Fix one possible panic when no destroy callback
	net/phy: micrel: configure intterupts after autoneg workaround
	ipv6: avoid unregistering inet6_dev for loopback
	net: dp83640: Avoid NULL pointer dereference.
	tcp: reset sk_rx_dst in tcp_disconnect()
	net: prevent sign extension in dev_get_stats()
	bpf: prevent leaking pointer via xadd on unpriviledged
	net: handle NAPI_GRO_FREE_STOLEN_HEAD case also in napi_frags_finish()
	ipv6: dad: don't remove dynamic addresses if link is down
	net: ipv6: Compare lwstate in detecting duplicate nexthops
	vrf: fix bug_on triggered by rx when destroying a vrf
	rds: tcp: use sock_create_lite() to create the accept socket
	brcmfmac: fix possible buffer overflow in brcmf_cfg80211_mgmt_tx()
	cfg80211: Define nla_policy for NL80211_ATTR_LOCAL_MESH_POWER_MODE
	cfg80211: Validate frequencies nested in NL80211_ATTR_SCAN_FREQUENCIES
	cfg80211: Check if PMKID attribute is of expected size
	irqchip/gic-v3: Fix out-of-bound access in gic_set_affinity
	parisc: Report SIGSEGV instead of SIGBUS when running out of stack
	parisc: use compat_sys_keyctl()
	parisc: DMA API: return error instead of BUG_ON for dma ops on non dma devs
	parisc/mm: Ensure IRQs are off in switch_mm()
	tools/lib/lockdep: Reduce MAX_LOCK_DEPTH to avoid overflowing lock_chain/: Depth
	kernel/extable.c: mark core_kernel_text notrace
	mm/list_lru.c: fix list_lru_count_node() to be race free
	fs/dcache.c: fix spin lockup issue on nlru->lock
	checkpatch: silence perl 5.26.0 unescaped left brace warnings
	binfmt_elf: use ELF_ET_DYN_BASE only for PIE
	arm: move ELF_ET_DYN_BASE to 4MB
	arm64: move ELF_ET_DYN_BASE to 4GB / 4MB
	powerpc: move ELF_ET_DYN_BASE to 4GB / 4MB
	s390: reduce ELF_ET_DYN_BASE
	exec: Limit arg stack to at most 75% of _STK_LIM
	vt: fix unchecked __put_user() in tioclinux ioctls
	mnt: In umount propagation reparent in a separate pass
	mnt: In propgate_umount handle visiting mounts in any order
	mnt: Make propagate_umount less slow for overlapping mount propagation trees
	selftests/capabilities: Fix the test_execve test
	tpm: Get rid of chip->pdev
	tpm: Provide strong locking for device removal
	Add "shutdown" to "struct class".
	tpm: Issue a TPM2_Shutdown for TPM2 devices.
	mm: fix overflow check in expand_upwards()
	crypto: talitos - Extend max key length for SHA384/512-HMAC and AEAD
	crypto: atmel - only treat EBUSY as transient if backlog
	crypto: sha1-ssse3 - Disable avx2
	crypto: caam - fix signals handling
	sched/topology: Fix overlapping sched_group_mask
	sched/topology: Optimize build_group_mask()
	PM / wakeirq: Convert to SRCU
	PM / QoS: return -EINVAL for bogus strings
	tracing: Use SOFTIRQ_OFFSET for softirq dectection for more accurate results
	KVM: x86: disable MPX if host did not enable MPX XSAVE features
	kvm: vmx: Do not disable intercepts for BNDCFGS
	kvm: x86: Guest BNDCFGS requires guest MPX support
	kvm: vmx: Check value written to IA32_BNDCFGS
	kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS
	Linux 4.4.78

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2017-07-21 09:14:57 +02:00
Kees Cook
86949eb964 exec: Limit arg stack to at most 75% of _STK_LIM
commit da029c11e6b12f321f36dac8771e833b65cec962 upstream.

To avoid pathological stack usage or the need to special-case setuid
execs, just limit all arg stack usage to at most 75% of _STK_LIM (6MB).

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:44:57 +02:00
Greg Kroah-Hartman
8c91412c32 Merge 4.4.75 into android-4.4
Changes in 4.4.75
	fs/exec.c: account for argv/envp pointers
	autofs: sanity check status reported with AUTOFS_DEV_IOCTL_FAIL
	lib/cmdline.c: fix get_options() overflow while parsing ranges
	KVM: PPC: Book3S HV: Preserve userspace HTM state properly
	CIFS: Improve readdir verbosity
	HID: Add quirk for Dell PIXART OEM mouse
	signal: Only reschedule timers on signals timers have sent
	powerpc/kprobes: Pause function_graph tracing during jprobes handling
	Input: i8042 - add Fujitsu Lifebook AH544 to notimeout list
	time: Fix clock->read(clock) race around clocksource changes
	target: Fix kref->refcount underflow in transport_cmd_finish_abort
	iscsi-target: Reject immediate data underflow larger than SCSI transfer length
	drm/radeon: add a PX quirk for another K53TK variant
	drm/radeon: add a quirk for Toshiba Satellite L20-183
	drm/amdgpu/atom: fix ps allocation size for EnableDispPowerGating
	drm/amdgpu: adjust default display clock
	USB: usbip: fix nonconforming hub descriptor
	rxrpc: Fix several cases where a padded len isn't checked in ticket decode
	of: Add check to of_scan_flat_dt() before accessing initial_boot_params
	mtd: spi-nor: fix spansion quad enable
	powerpc/slb: Force a full SLB flush when we insert for a bad EA
	usb: gadget: f_fs: avoid out of bounds access on comp_desc
	net: phy: Initialize mdio clock at probe function
	net: phy: fix marvell phy status reading
	nvme/quirk: Add a delay before checking for adapter readiness
	nvme: apply DELAY_BEFORE_CHK_RDY quirk at probe time too
	Linux 4.4.75

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2017-06-29 14:23:32 +02:00
Kees Cook
1d3d0f8b7c fs/exec.c: account for argv/envp pointers
commit 98da7d08850fb8bdeb395d6368ed15753304aa0c upstream.

When limiting the argv/envp strings during exec to 1/4 of the stack limit,
the storage of the pointers to the strings was not included.  This means
that an exec with huge numbers of tiny strings could eat 1/4 of the stack
limit in strings and then additional space would be later used by the
pointers to the strings.

For example, on 32-bit with a 8MB stack rlimit, an exec with 1677721
single-byte strings would consume less than 2MB of stack, the max (8MB /
4) amount allowed, but the pointers to the strings would consume the
remaining additional stack space (1677721 * 4 == 6710884).

The result (1677721 + 6710884 == 8388605) would exhaust stack space
entirely.  Controlling this stack exhaustion could result in
pathological behavior in setuid binaries (CVE-2017-1000365).

[akpm@linux-foundation.org: additional commenting from Kees]
Fixes: b6a2fea393 ("mm: variable length argument support")
Link: http://lkml.kernel.org/r/20170622001720.GA32173@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Qualys Security Advisory <qsa@qualys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-29 12:48:50 +02:00
Dmitry Shmidt
232c28fe23 Merge remote-tracking branch 'common/android-4.4' into android-4.4.y
Change-Id: Icf907f5067fb6da5935ab0d3271df54b8d5df405
2017-02-15 18:02:55 -08:00
Daniel Rosenberg
21fc44e40a ANDROID: vfs: Add permission2 for filesystems with per mount permissions
This allows filesystems to use their mount private data to
influence the permssions they return in permission2. It has
been separated into a new call to avoid disrupting current
permission users.

Change-Id: I9d416e3b8b6eca84ef3e336bd2af89ddd51df6ca
Signed-off-by: Daniel Rosenberg <drosen@google.com>
2017-01-26 15:53:30 -08:00
Eric W. Biederman
b35f34f669 exec: Ensure mm->user_ns contains the execed files
commit f84df2a6f268de584a201e8911384a2d244876e3 upstream.

When the user namespace support was merged the need to prevent
ptrace from revealing the contents of an unreadable executable
was overlooked.

Correct this oversight by ensuring that the executed file
or files are in mm->user_ns, by adjusting mm->user_ns.

Use the new function privileged_wrt_inode_uidgid to see if
the executable is a member of the user namespace, and as such
if having CAP_SYS_PTRACE in the user namespace should allow
tracing the executable.  If not update mm->user_ns to
the parent user namespace until an appropriate parent is found.

Reported-by: Jann Horn <jann@thejh.net>
Fixes: 9e4a36ece6 ("userns: Fail exec for suid and sgid binaries with ids outside our user namespace.")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-06 11:16:14 +01:00
Aleksa Sarai
0812936b11 fs: exec: apply CLOEXEC before changing dumpable task flags
commit 613cc2b6f272c1a8ad33aefa21cad77af23139f7 upstream.

If you have a process that has set itself to be non-dumpable, and it
then undergoes exec(2), any CLOEXEC file descriptors it has open are
"exposed" during a race window between the dumpable flags of the process
being reset for exec(2) and CLOEXEC being applied to the file
descriptors. This can be exploited by a process by attempting to access
/proc/<pid>/fd/... during this window, without requiring CAP_SYS_PTRACE.

The race in question is after set_dumpable has been (for get_link,
though the trace is basically the same for readlink):

[vfs]
-> proc_pid_link_inode_operations.get_link
   -> proc_pid_get_link
      -> proc_fd_access_allowed
         -> ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);

Which will return 0, during the race window and CLOEXEC file descriptors
will still be open during this window because do_close_on_exec has not
been called yet. As a result, the ordering of these calls should be
reversed to avoid this race window.

This is of particular concern to container runtimes, where joining a
PID namespace with file descriptors referring to the host filesystem
can result in security issues (since PRCTL_SET_DUMPABLE doesn't protect
against access of CLOEXEC file descriptors -- file descriptors which may
reference filesystem objects the container shouldn't have access to).

Cc: dev@opencontainers.org
Cc: <stable@vger.kernel.org> # v3.2+
Reported-by: Michael Crosby <crosbymichael@gmail.com>
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-06 11:16:14 +01:00
Eric W. Biederman
1c1f15f8eb ptrace: Capture the ptracer's creds not PT_PTRACE_CAP
commit 64b875f7ac8a5d60a4e191479299e931ee949b67 upstream.

When the flag PT_PTRACE_CAP was added the PTRACE_TRACEME path was
overlooked.  This can result in incorrect behavior when an application
like strace traces an exec of a setuid executable.

Further PT_PTRACE_CAP does not have enough information for making good
security decisions as it does not report which user namespace the
capability is in.  This has already allowed one mistake through
insufficient granulariy.

I found this issue when I was testing another corner case of exec and
discovered that I could not get strace to set PT_PTRACE_CAP even when
running strace as root with a full set of caps.

This change fixes the above issue with strace allowing stracing as
root a setuid executable without disabling setuid.  More fundamentaly
this change allows what is allowable at all times, by using the correct
information in it's decision.

Fixes: 4214e42f96d4 ("v2.4.9.11 -> v2.4.9.12")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-06 11:16:11 +01:00
Eric W. Biederman
90f8572b0f vfs: Commit to never having exectuables on proc and sysfs.
Today proc and sysfs do not contain any executable files.  Several
applications today mount proc or sysfs without noexec and nosuid and
then depend on there being no exectuables files on proc or sysfs.
Having any executable files show on proc or sysfs would cause
a user space visible regression, and most likely security problems.

Therefore commit to never allowing executables on proc and sysfs by
adding a new flag to mark them as filesystems without executables and
enforce that flag.

Test the flag where MNT_NOEXEC is tested today, so that the only user
visible effect will be that exectuables will be treated as if the
execute bit is cleared.

The filesystems proc and sysfs do not currently incoporate any
executable files so this does not result in any user visible effects.

This makes it unnecessary to vet changes to proc and sysfs tightly for
adding exectuable files or changes to chattr that would modify
existing files, as no matter what the individual file say they will
not be treated as exectuable files by the vfs.

Not having to vet changes to closely is important as without this we
are only one proc_create call (or another goof up in the
implementation of notify_change) from having problematic executables
on proc.  Those mistakes are all too easy to make and would create
a situation where there are security issues or the assumptions of
some program having to be broken (and cause userspace regressions).

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-10 10:39:25 -05:00
Helge Deller
d045c77c1a parisc,metag: Fix crashes due to stack randomization on stack-grows-upwards architectures
On architectures where the stack grows upwards (CONFIG_STACK_GROWSUP=y,
currently parisc and metag only) stack randomization sometimes leads to crashes
when the stack ulimit is set to lower values than STACK_RND_MASK (which is 8 MB
by default if not defined in arch-specific headers).

The problem is, that when the stack vm_area_struct is set up in fs/exec.c, the
additional space needed for the stack randomization (as defined by the value of
STACK_RND_MASK) was not taken into account yet and as such, when the stack
randomization code added a random offset to the stack start, the stack
effectively got smaller than what the user defined via rlimit_max(RLIMIT_STACK)
which then sometimes leads to out-of-stack situations and crashes.

This patch fixes it by adding the maximum possible amount of memory (based on
STACK_RND_MASK) which theoretically could be added by the stack randomization
code to the initial stack size. That way, the user-defined stack size is always
guaranteed to be at minimum what is defined via rlimit_max(RLIMIT_STACK).

This bug is currently not visible on the metag architecture, because on metag
STACK_RND_MASK is defined to 0 which effectively disables stack randomization.

The changes to fs/exec.c are inside an "#ifdef CONFIG_STACK_GROWSUP"
section, so it does not affect other platformws beside those where the
stack grows upwards (parisc and metag).

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: stable@vger.kernel.org # v3.16+
2015-05-12 22:03:44 +02:00
Jann Horn
8b01fc86b9 fs: take i_mutex during prepare_binprm for set[ug]id executables
This prevents a race between chown() and execve(), where chowning a
setuid-user binary to root would momentarily make the binary setuid
root.

This patch was mostly written by Linus Torvalds.

Signed-off-by: Jann Horn <jann@thejh.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-19 13:46:21 -07:00
Kirill Tkhai
dfcce791fb fs/exec.c:de_thread: move notify_count write under lock
We set sig->notify_count = -1 between RELEASE and ACQUIRE operations:

	spin_unlock_irq(lock);
	...
	if (!thread_group_leader(tsk)) {
		...
                for (;;) {
			sig->notify_count = -1;
                        write_lock_irq(&tasklist_lock);

There are no restriction on it so other processors may see this STORE
mixed with other STOREs in both areas limited by the spinlocks.

Probably, it may be reordered with the above

	sig->group_exit_task = tsk;
	sig->notify_count = zap_other_threads(tsk);

in some way.

Set it under tasklist_lock locked to be sure nothing will be reordered.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:07 -04:00
Davidlohr Bueso
6e399cd144 prctl: avoid using mmap_sem for exe_file serialization
Oleg cleverly suggested using xchg() to set the new mm->exe_file instead
of calling set_mm_exe_file() which requires some form of serialization --
mmap_sem in this case.  For archs that do not have atomic rmw instructions
we still fallback to a spinlock alternative, so this should always be
safe.  As such, we only need the mmap_sem for looking up the backing
vm_file, which can be done sharing the lock.  Naturally, this means we
need to manually deal with both the new and old file reference counting,
and we need not worry about the MMF_EXE_FILE_CHANGED bits, which can
probably be deleted in the future anyway.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:07 -04:00
Paul Moore
5168910413 fs: create proper filename objects using getname_kernel()
There are several areas in the kernel that create temporary filename
objects using the following pattern:

	int func(const char *name)
	{
		struct filename *file = { .name = name };
		...
		return 0;
	}

... which for the most part works okay, but it causes havoc within the
audit subsystem as the filename object does not persist beyond the
lifetime of the function.  This patch converts all of these temporary
filename objects into proper filename objects using getname_kernel()
and putname() which ensure that the filename object persists until the
audit subsystem is finished with it.

Also, a special thanks to Al Viro, Guenter Roeck, and Sabrina Dubroca
for helping resolve a difficult kernel panic on boot related to a
use-after-free problem in kern_path_create(); the thread can be seen
at the link below:

 * https://lkml.org/lkml/2015/1/20/710

This patch includes code that was either based on, or directly written
by Al in the above thread.

CC: viro@zeniv.linux.org.uk
CC: linux@roeck-us.net
CC: sd@queasysnail.net
CC: linux-fsdevel@vger.kernel.org
Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-01-23 00:22:20 -05:00
David Drysdale
51f39a1f0c syscalls: implement execveat() system call
This patchset adds execveat(2) for x86, and is derived from Meredydd
Luff's patch from Sept 2012 (https://lkml.org/lkml/2012/9/11/528).

The primary aim of adding an execveat syscall is to allow an
implementation of fexecve(3) that does not rely on the /proc filesystem,
at least for executables (rather than scripts).  The current glibc version
of fexecve(3) is implemented via /proc, which causes problems in sandboxed
or otherwise restricted environments.

Given the desire for a /proc-free fexecve() implementation, HPA suggested
(https://lkml.org/lkml/2006/7/11/556) that an execveat(2) syscall would be
an appropriate generalization.

Also, having a new syscall means that it can take a flags argument without
back-compatibility concerns.  The current implementation just defines the
AT_EMPTY_PATH and AT_SYMLINK_NOFOLLOW flags, but other flags could be
added in future -- for example, flags for new namespaces (as suggested at
https://lkml.org/lkml/2006/7/11/474).

Related history:
 - https://lkml.org/lkml/2006/12/27/123 is an example of someone
   realizing that fexecve() is likely to fail in a chroot environment.
 - http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=514043 covered
   documenting the /proc requirement of fexecve(3) in its manpage, to
   "prevent other people from wasting their time".
 - https://bugzilla.redhat.com/show_bug.cgi?id=241609 described a
   problem where a process that did setuid() could not fexecve()
   because it no longer had access to /proc/self/fd; this has since
   been fixed.

This patch (of 4):

Add a new execveat(2) system call.  execveat() is to execve() as openat()
is to open(): it takes a file descriptor that refers to a directory, and
resolves the filename relative to that.

In addition, if the filename is empty and AT_EMPTY_PATH is specified,
execveat() executes the file to which the file descriptor refers.  This
replicates the functionality of fexecve(), which is a system call in other
UNIXen, but in Linux glibc it depends on opening "/proc/self/fd/<fd>" (and
so relies on /proc being mounted).

The filename fed to the executed program as argv[0] (or the name of the
script fed to a script interpreter) will be of the form "/dev/fd/<fd>"
(for an empty filename) or "/dev/fd/<fd>/<filename>", effectively
reflecting how the executable was found.  This does however mean that
execution of a script in a /proc-less environment won't work; also, script
execution via an O_CLOEXEC file descriptor fails (as the file will not be
accessible after exec).

Based on patches by Meredydd Luff.

Signed-off-by: David Drysdale <drysdale@google.com>
Cc: Meredydd Luff <meredydd@senatehouse.org>
Cc: Shuah Khan <shuah.kh@samsung.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rich Felker <dalias@aerifal.cx>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 12:42:51 -08:00
Dave Hansen
abe1e395f6 fs: Do not include mpx.h in exec.c
We no longer need mpx.h in exec.c.  This will obviously also
break the build for non-x86 builds.  We get the MPX includes that
we need from mmu_context.h now.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141118003608.837015B3@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-18 02:01:40 +01:00
Dave Hansen
fe3d197f84 x86, mpx: On-demand kernel allocation of bounds tables
This is really the meat of the MPX patch set.  If there is one patch to
review in the entire series, this is the one.  There is a new ABI here
and this kernel code also interacts with userspace memory in a
relatively unusual manner.  (small FAQ below).

Long Description:

This patch adds two prctl() commands to provide enable or disable the
management of bounds tables in kernel, including on-demand kernel
allocation (See the patch "on-demand kernel allocation of bounds tables")
and cleanup (See the patch "cleanup unused bound tables"). Applications
do not strictly need the kernel to manage bounds tables and we expect
some applications to use MPX without taking advantage of this kernel
support. This means the kernel can not simply infer whether an application
needs bounds table management from the MPX registers.  The prctl() is an
explicit signal from userspace.

PR_MPX_ENABLE_MANAGEMENT is meant to be a signal from userspace to
require kernel's help in managing bounds tables.

PR_MPX_DISABLE_MANAGEMENT is the opposite, meaning that userspace don't
want kernel's help any more. With PR_MPX_DISABLE_MANAGEMENT, the kernel
won't allocate and free bounds tables even if the CPU supports MPX.

PR_MPX_ENABLE_MANAGEMENT will fetch the base address of the bounds
directory out of a userspace register (bndcfgu) and then cache it into
a new field (->bd_addr) in  the 'mm_struct'.  PR_MPX_DISABLE_MANAGEMENT
will set "bd_addr" to an invalid address.  Using this scheme, we can
use "bd_addr" to determine whether the management of bounds tables in
kernel is enabled.

Also, the only way to access that bndcfgu register is via an xsaves,
which can be expensive.  Caching "bd_addr" like this also helps reduce
the cost of those xsaves when doing table cleanup at munmap() time.
Unfortunately, we can not apply this optimization to #BR fault time
because we need an xsave to get the value of BNDSTATUS.

==== Why does the hardware even have these Bounds Tables? ====

MPX only has 4 hardware registers for storing bounds information.
If MPX-enabled code needs more than these 4 registers, it needs to
spill them somewhere. It has two special instructions for this
which allow the bounds to be moved between the bounds registers
and some new "bounds tables".

They are similar conceptually to a page fault and will be raised by
the MPX hardware during both bounds violations or when the tables
are not present. This patch handles those #BR exceptions for
not-present tables by carving the space out of the normal processes
address space (essentially calling the new mmap() interface indroduced
earlier in this patch set.) and then pointing the bounds-directory
over to it.

The tables *need* to be accessed and controlled by userspace because
the instructions for moving bounds in and out of them are extremely
frequent. They potentially happen every time a register pointing to
memory is dereferenced. Any direct kernel involvement (like a syscall)
to access the tables would obviously destroy performance.

==== Why not do this in userspace? ====

This patch is obviously doing this allocation in the kernel.
However, MPX does not strictly *require* anything in the kernel.
It can theoretically be done completely from userspace. Here are
a few ways this *could* be done. I don't think any of them are
practical in the real-world, but here they are.

Q: Can virtual space simply be reserved for the bounds tables so
   that we never have to allocate them?
A: As noted earlier, these tables are *HUGE*. An X-GB virtual
   area needs 4*X GB of virtual space, plus 2GB for the bounds
   directory. If we were to preallocate them for the 128TB of
   user virtual address space, we would need to reserve 512TB+2GB,
   which is larger than the entire virtual address space today.
   This means they can not be reserved ahead of time. Also, a
   single process's pre-popualated bounds directory consumes 2GB
   of virtual *AND* physical memory. IOW, it's completely
   infeasible to prepopulate bounds directories.

Q: Can we preallocate bounds table space at the same time memory
   is allocated which might contain pointers that might eventually
   need bounds tables?
A: This would work if we could hook the site of each and every
   memory allocation syscall. This can be done for small,
   constrained applications. But, it isn't practical at a larger
   scale since a given app has no way of controlling how all the
   parts of the app might allocate memory (think libraries). The
   kernel is really the only place to intercept these calls.

Q: Could a bounds fault be handed to userspace and the tables
   allocated there in a signal handler instead of in the kernel?
A: (thanks to tglx) mmap() is not on the list of safe async
   handler functions and even if mmap() would work it still
   requires locking or nasty tricks to keep track of the
   allocation state there.

Having ruled out all of the userspace-only approaches for managing
bounds tables that we could think of, we create them on demand in
the kernel.

Based-on-patch-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151829.AD4310DE@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-18 00:58:53 +01:00
Al Viro
19d860a140 handle suicide on late failure exits in execve() in search_binary_handler()
... rather than doing that in the guts of ->load_binary().
[updated to fix the bug spotted by Shentino - for SIGSEGV we really need
something stronger than send_sig_info(); again, better do that in one place]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-10-09 02:39:00 -04:00
Vladimir Davydov
41f727fde1 fork/exec: cleanup mm initialization
mm initialization on fork/exec is spread all over the place, which makes
the code look inconsistent.

We have mm_init(), which is supposed to init/nullify mm's internals, but
it doesn't init all the fields it should:

 - on fork ->mmap,mm_rb,vmacache_seqnum,map_count,mm_cpumask,locked_vm
   are zeroed in dup_mmap();

 - on fork ->pmd_huge_pte is zeroed in dup_mm(), immediately before
   calling mm_init();

 - ->cpu_vm_mask_var ptr is initialized by mm_init_cpumask(), which is
   called before mm_init() on both fork and exec;

 - ->context is initialized by init_new_context(), which is called after
   mm_init() on both fork and exec;

Let's consolidate all the initializations in mm_init() to make the code
look cleaner.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:23 -07:00
Kees Cook
c2e1f2e30d seccomp: implement SECCOMP_FILTER_FLAG_TSYNC
Applying restrictive seccomp filter programs to large or diverse
codebases often requires handling threads which may be started early in
the process lifetime (e.g., by code that is linked in). While it is
possible to apply permissive programs prior to process start up, it is
difficult to further restrict the kernel ABI to those threads after that
point.

This change adds a new seccomp syscall flag to SECCOMP_SET_MODE_FILTER for
synchronizing thread group seccomp filters at filter installation time.

When calling seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
filter) an attempt will be made to synchronize all threads in current's
threadgroup to its new seccomp filter program. This is possible iff all
threads are using a filter that is an ancestor to the filter current is
attempting to synchronize to. NULL filters (where the task is running as
SECCOMP_MODE_NONE) are also treated as ancestors allowing threads to be
transitioned into SECCOMP_MODE_FILTER. If prctrl(PR_SET_NO_NEW_PRIVS,
...) has been set on the calling thread, no_new_privs will be set for
all synchronized threads too. On success, 0 is returned. On failure,
the pid of one of the failing threads will be returned and no filters
will have been applied.

The race conditions against another thread are:
- requesting TSYNC (already handled by sighand lock)
- performing a clone (already handled by sighand lock)
- changing its filter (already handled by sighand lock)
- calling exec (handled by cred_guard_mutex)
The clone case is assisted by the fact that new threads will have their
seccomp state duplicated from their parent before appearing on the tasklist.

Holding cred_guard_mutex means that seccomp filters cannot be assigned
while in the middle of another thread's exec (potentially bypassing
no_new_privs or similar). The call to de_thread() may kill threads waiting
for the mutex.

Changes across threads to the filter pointer includes a barrier.

Based on patches by Will Drewry.

Suggested-by: Julien Tinnes <jln@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
2014-07-18 12:13:40 -07:00
Kees Cook
1d4457f999 sched: move no_new_privs into new atomic flags
Since seccomp transitions between threads requires updates to the
no_new_privs flag to be atomic, the flag must be part of an atomic flag
set. This moves the nnp flag into a separate task field, and introduces
accessors.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andy Lutomirski <luto@amacapital.net>
2014-07-18 12:13:38 -07:00
Adrian Hunter
82b897782d perf: Differentiate exec() and non-exec() comm events
perf tools like 'perf report' can aggregate samples by comm strings,
which generally works.  However, there are other potential use-cases.
For example, to pair up 'calls' with 'returns' accurately (from branch
events like Intel BTS) it is necessary to identify whether the process
has exec'd.  Although a comm event is generated when an 'exec' happens
it is also generated whenever the comm string is changed on a whim
(e.g. by prctl PR_SET_NAME).  This patch adds a flag to the comm event
to differentiate one case from the other.

In order to determine whether the kernel supports the new flag, a
selection bit named 'exec' is added to struct perf_event_attr.  The
bit does nothing but will cause perf_event_open() to fail if the bit
is set on kernels that do not have it defined.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/537D9EBE.7030806@intel.com
Cc: Paul Mackerras <paulus@samba.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-06 07:56:22 +02:00
Peter Zijlstra
e041e328c4 perf: Fix perf_event_comm() vs. exec() assumption
perf_event_comm() assumes that set_task_comm() is only called on
exec(), and in particular that its only called on current.

Neither are true, as Dave reported a WARN triggered by set_task_comm()
being called on !current.

Separate the exec() hook from the comm hook.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20140521153219.GH5226@laptop.programming.kicks-ass.net
[ Build fix. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-06 07:54:02 +02:00
James Hogan
d71f290b4e metag: Reduce maximum stack size to 256MB
Specify the maximum stack size for arches where the stack grows upward
(parisc and metag) in asm/processor.h rather than hard coding in
fs/exec.c so that metag can specify a smaller value of 256MB rather than
1GB.

This fixes a BUG on metag if the RLIMIT_STACK hard limit is increased
beyond a safe value by root. E.g. when starting a process after running
"ulimit -H -s unlimited" it will then attempt to use a stack size of the
maximum 1GB which is far too big for metag's limited user virtual
address space (stack_top is usually 0x3ffff000):

BUG: failure at fs/exec.c:589/shift_arg_pages()!

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # only needed for >= v3.9 (arch/metag)
2014-05-15 00:00:35 +01:00
Linus Torvalds
5166701b36 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "The first vfs pile, with deep apologies for being very late in this
  window.

  Assorted cleanups and fixes, plus a large preparatory part of iov_iter
  work.  There's a lot more of that, but it'll probably go into the next
  merge window - it *does* shape up nicely, removes a lot of
  boilerplate, gets rid of locking inconsistencie between aio_write and
  splice_write and I hope to get Kent's direct-io rewrite merged into
  the same queue, but some of the stuff after this point is having
  (mostly trivial) conflicts with the things already merged into
  mainline and with some I want more testing.

  This one passes LTP and xfstests without regressions, in addition to
  usual beating.  BTW, readahead02 in ltp syscalls testsuite has started
  giving failures since "mm/readahead.c: fix readahead failure for
  memoryless NUMA nodes and limit readahead pages" - might be a false
  positive, might be a real regression..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  missing bits of "splice: fix racy pipe->buffers uses"
  cifs: fix the race in cifs_writev()
  ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
  kill generic_file_buffered_write()
  ocfs2_file_aio_write(): switch to generic_perform_write()
  ceph_aio_write(): switch to generic_perform_write()
  xfs_file_buffered_aio_write(): switch to generic_perform_write()
  export generic_perform_write(), start getting rid of generic_file_buffer_write()
  generic_file_direct_write(): get rid of ppos argument
  btrfs_file_aio_write(): get rid of ppos
  kill the 5th argument of generic_file_buffered_write()
  kill the 4th argument of __generic_file_aio_write()
  lustre: don't open-code kernel_recvmsg()
  ocfs2: don't open-code kernel_recvmsg()
  drbd: don't open-code kernel_recvmsg()
  constify blk_rq_map_user_iov() and friends
  lustre: switch to kernel_sendmsg()
  ocfs2: don't open-code kernel_sendmsg()
  take iov_iter stuff to mm/iov_iter.c
  process_vm_access: tidy up a bit
  ...
2014-04-12 14:49:50 -07:00
Oleg Nesterov
23aebe1691 exec: kill bprm->tcomm[], simplify the "basename" logic
Starting from commit c4ad8f98be ("execve: use 'struct filename *' for
executable name passing") bprm->filename can not go away after
flush_old_exec(), so we do not need to save the binary name in
bprm->tcomm[] added by 96e02d1586 ("exec: fix use-after-free bug in
setup_new_exec()").

And there was never need for filename_to_taskname-like code, we can
simply do set_task_comm(kbasename(filename).

This patch has to change set_task_comm() and trace_task_rename() to
accept "const char *", but I think this change is also good.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:36:05 -07:00
Davidlohr Bueso
615d6e8756 mm: per-thread vma caching
This patch is a continuation of efforts trying to optimize find_vma(),
avoiding potentially expensive rbtree walks to locate a vma upon faults.
The original approach (https://lkml.org/lkml/2013/11/1/410), where the
largest vma was also cached, ended up being too specific and random,
thus further comparison with other approaches were needed.  There are
two things to consider when dealing with this, the cache hit rate and
the latency of find_vma().  Improving the hit-rate does not necessarily
translate in finding the vma any faster, as the overhead of any fancy
caching schemes can be too high to consider.

We currently cache the last used vma for the whole address space, which
provides a nice optimization, reducing the total cycles in find_vma() by
up to 250%, for workloads with good locality.  On the other hand, this
simple scheme is pretty much useless for workloads with poor locality.
Analyzing ebizzy runs shows that, no matter how many threads are
running, the mmap_cache hit rate is less than 2%, and in many situations
below 1%.

The proposed approach is to replace this scheme with a small per-thread
cache, maximizing hit rates at a very low maintenance cost.
Invalidations are performed by simply bumping up a 32-bit sequence
number.  The only expensive operation is in the rare case of a seq
number overflow, where all caches that share the same address space are
flushed.  Upon a miss, the proposed replacement policy is based on the
page number that contains the virtual address in question.  Concretely,
the following results are seen on an 80 core, 8 socket x86-64 box:

1) System bootup: Most programs are single threaded, so the per-thread
   scheme does improve ~50% hit rate by just adding a few more slots to
   the cache.

+----------------+----------+------------------+
| caching scheme | hit-rate | cycles (billion) |
+----------------+----------+------------------+
| baseline       | 50.61%   | 19.90            |
| patched        | 73.45%   | 13.58            |
+----------------+----------+------------------+

2) Kernel build: This one is already pretty good with the current
   approach as we're dealing with good locality.

+----------------+----------+------------------+
| caching scheme | hit-rate | cycles (billion) |
+----------------+----------+------------------+
| baseline       | 75.28%   | 11.03            |
| patched        | 88.09%   | 9.31             |
+----------------+----------+------------------+

3) Oracle 11g Data Mining (4k pages): Similar to the kernel build workload.

+----------------+----------+------------------+
| caching scheme | hit-rate | cycles (billion) |
+----------------+----------+------------------+
| baseline       | 70.66%   | 17.14            |
| patched        | 91.15%   | 12.57            |
+----------------+----------+------------------+

4) Ebizzy: There's a fair amount of variation from run to run, but this
   approach always shows nearly perfect hit rates, while baseline is just
   about non-existent.  The amounts of cycles can fluctuate between
   anywhere from ~60 to ~116 for the baseline scheme, but this approach
   reduces it considerably.  For instance, with 80 threads:

+----------------+----------+------------------+
| caching scheme | hit-rate | cycles (billion) |
+----------------+----------+------------------+
| baseline       | 1.06%    | 91.54            |
| patched        | 99.97%   | 14.18            |
+----------------+----------+------------------+

[akpm@linux-foundation.org: fix nommu build, per Davidlohr]
[akpm@linux-foundation.org: document vmacache_valid() logic]
[akpm@linux-foundation.org: attempt to untangle header files]
[akpm@linux-foundation.org: add vmacache_find() BUG_ON]
[hughd@google.com: add vmacache_valid_mm() (from Oleg)]
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: adjust and enhance comments]
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Tested-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:35:53 -07:00
Josh Triplett
69369a7003 fs, kernel: permit disabling the uselib syscall
uselib hasn't been used since libc5; glibc does not use it.  Support
turning it off.

When disabled, also omit the load_elf_library implementation from
binfmt_elf.c, which only uselib invokes.

bloat-o-meter:
add/remove: 0/4 grow/shrink: 0/1 up/down: 0/-785 (-785)
function                                     old     new   delta
padzero                                       39      36      -3
uselib_flags                                  20       -     -20
sys_uselib                                   168       -    -168
SyS_uselib                                   168       -    -168
load_elf_library                             426       -    -426

The new CONFIG_USELIB defaults to `y'.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:21:05 -07:00
Al Viro
ec69557982 read_code(): go through vfs_read() instead of calling the method directly
... and don't skip on sanity checks.  It's *not* a hot path, TYVM
(a couple of calls per a.out execve(), for pity sake) and headers of
random a.out binary are not to be trusted.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:24 -04:00
Heiko Carstens
625b1d7e81 fs/compat: convert to COMPAT_SYSCALL_DEFINE
Convert all compat system call functions where all parameter types
have a size of four or less than four bytes, or are pointer types
to COMPAT_SYSCALL_DEFINE.
The implicit casts within COMPAT_SYSCALL_DEFINE will perform proper
zero and sign extension to 64 bit of all parameters if needed.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-03-06 16:30:43 +01:00
Linus Torvalds
c4ad8f98be execve: use 'struct filename *' for executable name passing
This changes 'do_execve()' to get the executable name as a 'struct
filename', and to free it when it is done.  This is what the normal
users want, and it simplifies and streamlines their error handling.

The controlled lifetime of the executable name also fixes a
use-after-free problem with the trace_sched_process_exec tracepoint: the
lifetime of the passed-in string for kernel users was not at all
obvious, and the user-mode helper code used UMH_WAIT_EXEC to serialize
the pathname allocation lifetime with the execve() having finished,
which in turn meant that the trace point that happened after
mm_release() of the old process VM ended up using already free'd memory.

To solve the kernel string lifetime issue, this simply introduces
"getname_kernel()" that works like the normal user-space getname()
function, except with the source coming from kernel memory.

As Oleg points out, this also means that we could drop the tcomm[] array
from 'struct linux_binprm', since the pathname lifetime now covers
setup_new_exec().  That would be a separate cleanup.

Reported-by: Igor Zhbanov <i.zhbanov@samsung.com>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-02-05 12:54:53 -08:00
Richard Weinberger
3b96d7db3b fs/exec.c: call arch_pick_mmap_layout() only once
Currently both setup_new_exec() and flush_old_exec() issue a call to
arch_pick_mmap_layout().  As setup_new_exec() and flush_old_exec() are
always called pairwise arch_pick_mmap_layout() is called twice.

This patch removes one call from setup_new_exec() to have it only called
once.

Signed-off-by: Richard Weinberger <richard@nod.at>
Tested-by: Pat Erley <pat-lkml@erley.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:37:02 -08:00
Zhang Yi
b88fae644e exec: avoid propagating PF_NO_SETAFFINITY into userspace child
Userspace process doesn't want the PF_NO_SETAFFINITY, but its parent may be
a kernel worker thread which has PF_NO_SETAFFINITY set, and this worker thread
can do kernel_thread() to create the child.
Clearing this flag in usersapce child to enable its migrating capability.

Signed-off-by: Zhang Yi <zhang.yi20@zte.com.cn>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:37:02 -08:00
Oleg Nesterov
98611e4e6a exec: kill task_struct->did_exec
We can kill either task->did_exec or PF_FORKNOEXEC, they are mutually
exclusive.  The patch kills ->did_exec because it has a single user.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:37:02 -08:00
Oleg Nesterov
63e46b95e9 exec: move the final allow_write_access/fput into free_bprm()
Both success/failure paths cleanup bprm->file, we can move this
code into free_bprm() to simlify and cleanup this logic.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:37:02 -08:00
Oleg Nesterov
9e00cdb091 exec:check_unsafe_exec: kill the dead -EAGAIN and clear_in_exec logic
fs_struct->in_exec == T means that this ->fs is used by a single process
(thread group), and one of the treads does do_execve().

To avoid the mt-exec races this code has the following complications:

	1. check_unsafe_exec() returns -EBUSY if ->in_exec was
	   already set by another thread.

	2. do_execve_common() records "clear_in_exec" to ensure
	   that the error path can only clear ->in_exec if it was
	   set by current.

However, after 9b1bf12d5d "signals: move cred_guard_mutex from
task_struct to signal_struct" we do not need these complications:

	1. We can't race with our sub-thread, this is called under
	   per-process ->cred_guard_mutex. And we can't race with
	   another CLONE_FS task, we already checked that this fs
	   is not shared.

	   We can remove the  dead -EAGAIN logic.

	2. "out_unmark:" in do_execve_common() is either called
	   under ->cred_guard_mutex, or after de_thread() which
	   kills other threads, so we can't race with sub-thread
	   which could set ->in_exec. And if ->fs is shared with
	   another process ->in_exec should be false anyway.

	   We can clear in_exec unconditionally.

This also means that check_unsafe_exec() can be void.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:37:02 -08:00
Oleg Nesterov
83f62a2eac exec:check_unsafe_exec: use while_each_thread() rather than next_thread()
next_thread() should be avoided, change check_unsafe_exec() to use
while_each_thread().

Nobody except signal->curr_target actually needs next_thread-like code,
and we need to change (fix) this interface.  This particular code is fine,
p == current.  But in general the code like this can loop forever if p
exits and next_thread(t) can't reach the unhashed thread.

This also saves 32 bytes.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:37:02 -08:00