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Merge 4.4.129 into android-4.4
Changes in 4.4.129
media: v4l2-compat-ioctl32: don't oops on overlay
parisc: Fix out of array access in match_pci_device()
perf intel-pt: Fix overlap detection to identify consecutive buffers correctly
perf intel-pt: Fix sync_switch
perf intel-pt: Fix error recovery from missing TIP packet
perf intel-pt: Fix timestamp following overflow
radeon: hide pointless #warning when compile testing
Revert "perf tests: Decompress kernel module before objdump"
block/loop: fix deadlock after loop_set_status
s390/qdio: don't retry EQBS after CCQ 96
s390/qdio: don't merge ERROR output buffers
s390/ipl: ensure loadparm valid flag is set
getname_kernel() needs to make sure that ->name != ->iname in long case
rtl8187: Fix NULL pointer dereference in priv->conf_mutex
hwmon: (ina2xx) Fix access to uninitialized mutex
cdc_ether: flag the Cinterion AHS8 modem by gemalto as WWAN
slip: Check if rstate is initialized before uncompressing
lan78xx: Correctly indicate invalid OTP
x86/hweight: Get rid of the special calling convention
x86/hweight: Don't clobber %rdi
tty: make n_tty_read() always abort if hangup is in progress
ubifs: Check ubifs_wbuf_sync() return code
ubi: fastmap: Don't flush fastmap work on detach
ubi: Fix error for write access
ubi: Reject MLC NAND
fs/reiserfs/journal.c: add missing resierfs_warning() arg
resource: fix integer overflow at reallocation
ipc/shm: fix use-after-free of shm file via remap_file_pages()
mm, slab: reschedule cache_reap() on the same CPU
usb: musb: gadget: misplaced out of bounds check
ARM: dts: at91: at91sam9g25: fix mux-mask pinctrl property
ARM: dts: at91: sama5d4: fix pinctrl compatible string
xen-netfront: Fix hang on device removal
regmap: Fix reversed bounds check in regmap_raw_write()
ACPI / video: Add quirk to force acpi-video backlight on Samsung 670Z5E
ACPI / hotplug / PCI: Check presence of slot itself in get_slot_status()
USB:fix USB3 devices behind USB3 hubs not resuming at hibernate thaw
usb: dwc3: pci: Properly cleanup resource
HID: i2c-hid: fix size check and type usage
powerpc/powernv: Handle unknown OPAL errors in opal_nvram_write()
powerpc/64: Fix smp_wmb barrier definition use use lwsync consistently
powerpc/powernv: define a standard delay for OPAL_BUSY type retry loops
powerpc/powernv: Fix OPAL NVRAM driver OPAL_BUSY loops
HID: Fix hid_report_len usage
HID: core: Fix size as type u32
ASoC: ssm2602: Replace reg_default_raw with reg_default
thunderbolt: Resume control channel after hibernation image is created
random: use a tighter cap in credit_entropy_bits_safe()
jbd2: if the journal is aborted then don't allow update of the log tail
ext4: don't update checksum of new initialized bitmaps
ext4: fail ext4_iget for root directory if unallocated
RDMA/ucma: Don't allow setting RDMA_OPTION_IB_PATH without an RDMA device
ALSA: pcm: Fix UAF at PCM release via PCM timer access
IB/srp: Fix srp_abort()
IB/srp: Fix completion vector assignment algorithm
dmaengine: at_xdmac: fix rare residue corruption
um: Use POSIX ucontext_t instead of struct ucontext
iommu/vt-d: Fix a potential memory leak
mmc: jz4740: Fix race condition in IRQ mask update
clk: mvebu: armada-38x: add support for 1866MHz variants
clk: mvebu: armada-38x: add support for missing clocks
clk: bcm2835: De-assert/assert PLL reset signal when appropriate
thermal: imx: Fix race condition in imx_thermal_probe()
watchdog: f71808e_wdt: Fix WD_EN register read
ALSA: oss: consolidate kmalloc/memset 0 call to kzalloc
ALSA: pcm: Use ERESTARTSYS instead of EINTR in OSS emulation
ALSA: pcm: Avoid potential races between OSS ioctls and read/write
ALSA: pcm: Return -EBUSY for OSS ioctls changing busy streams
ALSA: pcm: Fix mutex unbalance in OSS emulation ioctls
ALSA: pcm: Fix endless loop for XRUN recovery in OSS emulation
vfio-pci: Virtualize PCIe & AF FLR
vfio/pci: Virtualize Maximum Payload Size
vfio/pci: Virtualize Maximum Read Request Size
ext4: don't allow r/w mounts if metadata blocks overlap the superblock
drm/radeon: Fix PCIe lane width calculation
ext4: fix crashes in dioread_nolock mode
ext4: fix deadlock between inline_data and ext4_expand_extra_isize_ea()
ALSA: line6: Use correct endpoint type for midi output
ALSA: rawmidi: Fix missing input substream checks in compat ioctls
ALSA: hda - New VIA controller suppor no-snoop path
HID: hidraw: Fix crash on HIDIOCGFEATURE with a destroyed device
MIPS: uaccess: Add micromips clobbers to bzero invocation
MIPS: memset.S: EVA & fault support for small_memset
MIPS: memset.S: Fix return of __clear_user from Lpartial_fixup
MIPS: memset.S: Fix clobber of v1 in last_fixup
powerpc/eeh: Fix enabling bridge MMIO windows
powerpc/lib: Fix off-by-one in alternate feature patching
jffs2_kill_sb(): deal with failed allocations
hypfs_kill_super(): deal with failed allocations
rpc_pipefs: fix double-dput()
Don't leak MNT_INTERNAL away from internal mounts
autofs: mount point create should honour passed in mode
mm: allow GFP_{FS,IO} for page_cache_read page cache allocation
mm/filemap.c: fix NULL pointer in page_cache_tree_insert()
ext4: bugfix for mmaped pages in mpage_release_unused_pages()
fanotify: fix logic of events on child
writeback: safer lock nesting
Linux 4.4.129
Change-Id: I8806d2cc92fe512f27a349e8f630ced0cac9a8d7
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 30ce4d1903e1d8a7ccd110860a5eef3c638ed8be upstream.
missed it in "kill struct filename.separate" several years ago.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 4.4.123 into android-4.4
Changes in 4.4.123
blkcg: fix double free of new_blkg in blkcg_init_queue
Input: tsc2007 - check for presence and power down tsc2007 during probe
staging: speakup: Replace BUG_ON() with WARN_ON().
staging: wilc1000: add check for kmalloc allocation failure.
HID: reject input outside logical range only if null state is set
drm: qxl: Don't alloc fbdev if emulation is not supported
ath10k: fix a warning during channel switch with multiple vaps
PCI/MSI: Stop disabling MSI/MSI-X in pci_device_shutdown()
selinux: check for address length in selinux_socket_bind()
perf sort: Fix segfault with basic block 'cycles' sort dimension
i40e: Acquire NVM lock before reads on all devices
i40e: fix ethtool to get EEPROM data from X722 interface
perf tools: Make perf_event__synthesize_mmap_events() scale
drivers: net: xgene: Fix hardware checksum setting
drm: Defer disabling the vblank IRQ until the next interrupt (for instant-off)
ath10k: disallow DFS simulation if DFS channel is not enabled
perf probe: Return errno when not hitting any event
HID: clamp input to logical range if no null state
net/8021q: create device with all possible features in wanted_features
ARM: dts: Adjust moxart IRQ controller and flags
batman-adv: handle race condition for claims between gateways
of: fix of_device_get_modalias returned length when truncating buffers
solo6x10: release vb2 buffers in solo_stop_streaming()
scsi: ipr: Fix missed EH wakeup
media: i2c/soc_camera: fix ov6650 sensor getting wrong clock
timers, sched_clock: Update timeout for clock wrap
sysrq: Reset the watchdog timers while displaying high-resolution timers
Input: qt1070 - add OF device ID table
sched: act_csum: don't mangle TCP and UDP GSO packets
ASoC: rcar: ssi: don't set SSICR.CKDV = 000 with SSIWSR.CONT
spi: omap2-mcspi: poll OMAP2_MCSPI_CHSTAT_RXS for PIO transfer
tcp: sysctl: Fix a race to avoid unexpected 0 window from space
dmaengine: imx-sdma: add 1ms delay to ensure SDMA channel is stopped
driver: (adm1275) set the m,b and R coefficients correctly for power
mm: Fix false-positive VM_BUG_ON() in page_cache_{get,add}_speculative()
blk-throttle: make sure expire time isn't too big
f2fs: relax node version check for victim data in gc
bonding: refine bond_fold_stats() wrap detection
braille-console: Fix value returned by _braille_console_setup
drm/vmwgfx: Fixes to vmwgfx_fb
vxlan: vxlan dev should inherit lowerdev's gso_max_size
NFC: nfcmrvl: Include unaligned.h instead of access_ok.h
NFC: nfcmrvl: double free on error path
ARM: dts: r8a7790: Correct parent of SSI[0-9] clocks
ARM: dts: r8a7791: Correct parent of SSI[0-9] clocks
powerpc: Avoid taking a data miss on every userspace instruction miss
net/faraday: Add missing include of of.h
ARM: dts: koelsch: Correct clock frequency of X2 DU clock input
reiserfs: Make cancel_old_flush() reliable
ALSA: firewire-digi00x: handle all MIDI messages on streaming packets
fm10k: correctly check if interface is removed
scsi: ses: don't get power status of SES device slot on probe
apparmor: Make path_max parameter readonly
iommu/iova: Fix underflow bug in __alloc_and_insert_iova_range
video: ARM CLCD: fix dma allocation size
drm/radeon: Fail fb creation from imported dma-bufs.
drm/amdgpu: Fail fb creation from imported dma-bufs. (v2)
coresight: Fixes coresight DT parse to get correct output port ID.
MIPS: BPF: Quit clobbering callee saved registers in JIT code.
MIPS: BPF: Fix multiple problems in JIT skb access helpers.
MIPS: r2-on-r6-emu: Fix BLEZL and BGTZL identification
MIPS: r2-on-r6-emu: Clear BLTZALL and BGEZALL debugfs counters
regulator: isl9305: fix array size
md/raid6: Fix anomily when recovering a single device in RAID6.
usb: dwc2: Make sure we disconnect the gadget state
usb: gadget: dummy_hcd: Fix wrong power status bit clear/reset in dummy_hub_control()
drivers/perf: arm_pmu: handle no platform_device
perf inject: Copy events when reordering events in pipe mode
perf session: Don't rely on evlist in pipe mode
scsi: sg: check for valid direction before starting the request
scsi: sg: close race condition in sg_remove_sfp_usercontext()
kprobes/x86: Fix kprobe-booster not to boost far call instructions
kprobes/x86: Set kprobes pages read-only
pwm: tegra: Increase precision in PWM rate calculation
wil6210: fix memory access violation in wil_memcpy_from/toio_32
drm/edid: set ELD connector type in drm_edid_to_eld()
video/hdmi: Allow "empty" HDMI infoframes
HID: elo: clear BTN_LEFT mapping
ARM: dts: exynos: Correct Trats2 panel reset line
sched: Stop switched_to_rt() from sending IPIs to offline CPUs
sched: Stop resched_cpu() from sending IPIs to offline CPUs
test_firmware: fix setting old custom fw path back on exit
net: xfrm: allow clearing socket xfrm policies.
mtd: nand: fix interpretation of NAND_CMD_NONE in nand_command[_lp]()
ARM: dts: am335x-pepper: Fix the audio CODEC's reset pin
ARM: dts: omap3-n900: Fix the audio CODEC's reset pin
ath10k: update tdls teardown state to target
cpufreq: Fix governor module removal race
clk: qcom: msm8916: fix mnd_width for codec_digcodec
ath10k: fix invalid STS_CAP_OFFSET_MASK
tools/usbip: fixes build with musl libc toolchain
spi: sun6i: disable/unprepare clocks on remove
scsi: core: scsi_get_device_flags_keyed(): Always return device flags
scsi: devinfo: apply to HP XP the same flags as Hitachi VSP
scsi: dh: add new rdac devices
media: cpia2: Fix a couple off by one bugs
veth: set peer GSO values
drm/amdkfd: Fix memory leaks in kfd topology
agp/intel: Flush all chipset writes after updating the GGTT
mac80211_hwsim: enforce PS_MANUAL_POLL to be set after PS_ENABLED
mac80211: remove BUG() when interface type is invalid
ASoC: nuc900: Fix a loop timeout test
ipvlan: add L2 check for packets arriving via virtual devices
rcutorture/configinit: Fix build directory error message
ima: relax requiring a file signature for new files with zero length
selftests/x86/entry_from_vm86: Exit with 1 if we fail
selftests/x86: Add tests for User-Mode Instruction Prevention
selftests/x86: Add tests for the STR and SLDT instructions
selftests/x86/entry_from_vm86: Add test cases for POPF
x86/vm86/32: Fix POPF emulation
x86/mm: Fix vmalloc_fault to use pXd_large
ALSA: pcm: Fix UAF in snd_pcm_oss_get_formats()
ALSA: hda - Revert power_save option default value
ALSA: seq: Fix possible UAF in snd_seq_check_queue()
ALSA: seq: Clear client entry before deleting else at closing
drm/amdgpu/dce: Don't turn off DP sink when disconnected
fs: Teach path_connected to handle nfs filesystems with multiple roots.
lock_parent() needs to recheck if dentry got __dentry_kill'ed under it
fs/aio: Add explicit RCU grace period when freeing kioctx
fs/aio: Use RCU accessors for kioctx_table->table[]
irqchip/gic-v3-its: Ensure nr_ites >= nr_lpis
scsi: sg: fix SG_DXFER_FROM_DEV transfers
scsi: sg: fix static checker warning in sg_is_valid_dxfer
scsi: sg: only check for dxfer_len greater than 256M
ARM: dts: LogicPD Torpedo: Fix I2C1 pinmux
btrfs: alloc_chunk: fix DUP stripe size handling
btrfs: Fix use-after-free when cleaning up fs_devs with a single stale device
USB: gadget: udc: Add missing platform_device_put() on error in bdc_pci_probe()
usb: gadget: bdc: 64-bit pointer capability check
bpf: fix incorrect sign extension in check_alu_op()
Linux 4.4.123
Change-Id: Ieb89411248f93522dde29edb8581f8ece22e33a7
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 95dd77580ccd66a0da96e6d4696945b8cea39431 upstream.
On nfsv2 and nfsv3 the nfs server can export subsets of the same
filesystem and report the same filesystem identifier, so that the nfs
client can know they are the same filesystem. The subsets can be from
disjoint directory trees. The nfsv2 and nfsv3 filesystems provides no
way to find the common root of all directory trees exported form the
server with the same filesystem identifier.
The practical result is that in struct super s_root for nfs s_root is
not necessarily the root of the filesystem. The nfs mount code sets
s_root to the root of the first subset of the nfs filesystem that the
kernel mounts.
This effects the dcache invalidation code in generic_shutdown_super
currently called shrunk_dcache_for_umount and that code for years
has gone through an additional list of dentries that might be dentry
trees that need to be freed to accomodate nfs.
When I wrote path_connected I did not realize nfs was so special, and
it's hueristic for avoiding calling is_subdir can fail.
The practical case where this fails is when there is a move of a
directory from the subtree exposed by one nfs mount to the subtree
exposed by another nfs mount. This move can happen either locally or
remotely. With the remote case requiring that the move directory be cached
before the move and that after the move someone walks the path
to where the move directory now exists and in so doing causes the
already cached directory to be moved in the dcache through the magic
of d_splice_alias.
If someone whose working directory is in the move directory or a
subdirectory and now starts calling .. from the initial mount of nfs
(where s_root == mnt_root), then path_connected as a heuristic will
not bother with the is_subdir check. As s_root really is not the root
of the nfs filesystem this heuristic is wrong, and the path may
actually not be connected and path_connected can fail.
The is_subdir function might be cheap enough that we can call it
unconditionally. Verifying that will take some benchmarking and
the result may not be the same on all kernels this fix needs
to be backported to. So I am avoiding that for now.
Filesystems with snapshots such as nilfs and btrfs do something
similar. But as the directory tree of the snapshots are disjoint
from one another and from the main directory tree rename won't move
things between them and this problem will not occur.
Cc: stable@vger.kernel.org
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Fixes: 397d425dc2 ("vfs: Test for and handle paths that are unreachable from their mnt_root")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 4.4.117 into android-4.4
Changes in 4.4.117
IB/mlx4: Fix incorrectly releasing steerable UD QPs when have only ETH ports
PM / devfreq: Propagate error from devfreq_add_device()
s390: fix handling of -1 in set{,fs}[gu]id16 syscalls
ARM: dts: STi: Add gpio polarity for "hdmi,hpd-gpio" property
arm: spear600: Add missing interrupt-parent of rtc
arm: spear13xx: Fix dmas cells
arm: spear13xx: Fix spics gpio controller's warning
ALSA: seq: Fix regression by incorrect ioctl_mutex usages
KVM/x86: Reduce retpoline performance impact in slot_handle_level_range(), by always inlining iterator helper methods
x86/cpu: Change type of x86_cache_size variable to unsigned int
drm/radeon: adjust tested variable
rtc-opal: Fix handling of firmware error codes, prevent busy loops
ext4: save error to disk in __ext4_grp_locked_error()
ext4: correct documentation for grpid mount option
mm: hide a #warning for COMPILE_TEST
video: fbdev: atmel_lcdfb: fix display-timings lookup
console/dummy: leave .con_font_get set to NULL
rtlwifi: rtl8821ae: Fix connection lost problem correctly
Btrfs: fix deadlock in run_delalloc_nocow
Btrfs: fix crash due to not cleaning up tree log block's dirty bits
Btrfs: fix unexpected -EEXIST when creating new inode
ALSA: hda - Fix headset mic detection problem for two Dell machines
ALSA: usb-audio: Fix UAC2 get_ctl request with a RANGE attribute
ALSA: hda/realtek: PCI quirk for Fujitsu U7x7
ALSA: usb-audio: add implicit fb quirk for Behringer UFX1204
ALSA: seq: Fix racy pool initializations
mvpp2: fix multicast address filter
dm: correctly handle chained bios in dec_pending()
x86: fix build warnign with 32-bit PAE
vfs: don't do RCU lookup of empty pathnames
ARM: pxa/tosa-bt: add MODULE_LICENSE tag
ARM: dts: s5pv210: add interrupt-parent for ohci
media: r820t: fix r820t_write_reg for KASAN
Linux 4.4.117
Change-Id: Id192d691d19a99889dc5d36711f18576f48f2981
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit c0eb027e5aef70b71e5a38ee3e264dc0b497f343 upstream.
Normal pathname lookup doesn't allow empty pathnames, but using
AT_EMPTY_PATH (with name_to_handle_at() or fstatat(), for example) you
can trigger an empty pathname lookup.
And not only is the RCU lookup in that case entirely unnecessary
(because we'll obviously immediately finalize the end result), it is
actively wrong.
Why? An empth path is a special case that will return the original
'dirfd' dentry - and that dentry may not actually be RCU-free'd,
resulting in a potential use-after-free if we were to initialize the
path lazily under the RCU read lock and depend on complete_walk()
finalizing the dentry.
Found by syzkaller and KASAN.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 4.4.80 into android-4.4
Changes in 4.4.80
af_key: Add lock to key dump
pstore: Make spinlock per zone instead of global
net: reduce skb_warn_bad_offload() noise
powerpc/pseries: Fix of_node_put() underflow during reconfig remove
crypto: authencesn - Fix digest_null crash
md/raid5: add thread_group worker async_tx_issue_pending_all
drm/vmwgfx: Fix gcc-7.1.1 warning
drm/nouveau/bar/gf100: fix access to upper half of BAR2
KVM: PPC: Book3S HV: Context-switch EBB registers properly
KVM: PPC: Book3S HV: Restore critical SPRs to host values on guest exit
KVM: PPC: Book3S HV: Reload HTM registers explicitly
KVM: PPC: Book3S HV: Save/restore host values of debug registers
Revert "powerpc/numa: Fix percpu allocations to be NUMA aware"
Staging: comedi: comedi_fops: Avoid orphaned proc entry
drm/rcar: Nuke preclose hook
drm: rcar-du: Perform initialization/cleanup at probe/remove time
drm: rcar-du: Simplify and fix probe error handling
perf intel-pt: Fix ip compression
perf intel-pt: Fix last_ip usage
perf intel-pt: Use FUP always when scanning for an IP
perf intel-pt: Ensure never to set 'last_ip' when packet 'count' is zero
xfs: don't BUG() on mixed direct and mapped I/O
nfc: fdp: fix NULL pointer dereference
net: phy: Do not perform software reset for Generic PHY
isdn: Fix a sleep-in-atomic bug
isdn/i4l: fix buffer overflow
ath10k: fix null deref on wmi-tlv when trying spectral scan
wil6210: fix deadlock when using fw_no_recovery option
mailbox: always wait in mbox_send_message for blocking Tx mode
mailbox: skip complete wait event if timer expired
mailbox: handle empty message in tx_tick
mpt3sas: Don't overreach ioc->reply_post[] during initialization
kaweth: fix firmware download
kaweth: fix oops upon failed memory allocation
sched/cgroup: Move sched_online_group() back into css_online() to fix crash
PM / Domains: defer dev_pm_domain_set() until genpd->attach_dev succeeds if present
RDMA/uverbs: Fix the check for port number
libnvdimm, btt: fix btt_rw_page not returning errors
ipmi/watchdog: fix watchdog timeout set on reboot
dentry name snapshots
v4l: s5c73m3: fix negation operator
Make file credentials available to the seqfile interfaces
/proc/iomem: only expose physical resource addresses to privileged users
vlan: Propagate MAC address to VLANs
pstore: Allow prz to control need for locking
pstore: Correctly initialize spinlock and flags
pstore: Use dynamic spinlock initializer
net: skb_needs_check() accepts CHECKSUM_NONE for tx
sched/cputime: Fix prev steal time accouting during CPU hotplug
xen/blkback: don't free be structure too early
xen/blkback: don't use xen_blkif_get() in xen-blkback kthread
tpm: fix a kernel memory leak in tpm-sysfs.c
tpm: Replace device number bitmap with IDR
x86/mce/AMD: Make the init code more robust
r8169: add support for RTL8168 series add-on card.
ARM: dts: n900: Mark eMMC slot with no-sdio and no-sd flags
ipv6: Should use consistent conditional judgement for ip6 fragment between __ip6_append_data and ip6_finish_output
net/mlx4: Remove BUG_ON from ICM allocation routine
drm/msm: Ensure that the hardware write pointer is valid
drm/msm: Verify that MSM_SUBMIT_BO_FLAGS are set
vfio-pci: use 32-bit comparisons for register address for gcc-4.5
irqchip/keystone: Fix "scheduling while atomic" on rt
ASoC: tlv320aic3x: Mark the RESET register as volatile
spi: dw: Make debugfs name unique between instances
ASoC: nau8825: fix invalid configuration in Pre-Scalar of FLL
irqchip/mxs: Enable SKIP_SET_WAKE and MASK_ON_SUSPEND
openrisc: Add _text symbol to fix ksym build error
dmaengine: ioatdma: Add Skylake PCI Dev ID
dmaengine: ioatdma: workaround SKX ioatdma version
dmaengine: ti-dma-crossbar: Add some 'of_node_put()' in error path.
ARM64: zynqmp: Fix W=1 dtc 1.4 warnings
ARM64: zynqmp: Fix i2c node's compatible string
ARM: s3c2410_defconfig: Fix invalid values for NF_CT_PROTO_*
ACPI / scan: Prefer devices without _HID/_CID for _ADR matching
usb: gadget: Fix copy/pasted error message
Btrfs: adjust outstanding_extents counter properly when dio write is split
tools lib traceevent: Fix prev/next_prio for deadline tasks
xfrm: Don't use sk_family for socket policy lookups
perf tools: Install tools/lib/traceevent plugins with install-bin
perf symbols: Robustify reading of build-id from sysfs
video: fbdev: cobalt_lcdfb: Handle return NULL error from devm_ioremap
vfio-pci: Handle error from pci_iomap
arm64: mm: fix show_pte KERN_CONT fallout
nvmem: imx-ocotp: Fix wrong register size
sh_eth: enable RX descriptor word 0 shift on SH7734
ALSA: usb-audio: test EP_FLAG_RUNNING at urb completion
HID: ignore Petzl USB headlamp
scsi: fnic: Avoid sending reset to firmware when another reset is in progress
scsi: snic: Return error code on memory allocation failure
ASoC: dpcm: Avoid putting stream state to STOP when FE stream is paused
Linux 4.4.80
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit 49d31c2f389acfe83417083e1208422b4091cd9e upstream.
take_dentry_name_snapshot() takes a safe snapshot of dentry name;
if the name is a short one, it gets copied into caller-supplied
structure, otherwise an extra reference to external name is grabbed
(those are never modified). In either case the pointer to stable
string is stored into the same structure.
dentry must be held by the caller of take_dentry_name_snapshot(),
but may be freely dropped afterwards - the snapshot will stay
until destroyed by release_dentry_name_snapshot().
Intended use:
struct name_snapshot s;
take_dentry_name_snapshot(&s, dentry);
...
access s.name
...
release_dentry_name_snapshot(&s);
Replaces fsnotify_oldname_...(), gets used in fsnotify to obtain the name
to pass down with event.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This allows filesystems to use their mount private data to
influence the permssions they use in setattr2. It has
been separated into a new call to avoid disrupting current
setattr users.
Change-Id: I19959038309284448f1b7f232d579674ef546385
Signed-off-by: Daniel Rosenberg <drosen@google.com>
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>
[ Upstream commit 2d7f9e2ad35e4e7a3086231f19bfab33c6a8a64a ]
Filesystem uids which don't map into a user namespace may result
in inode->i_uid being INVALID_UID. A symlink and its parent
could have different owners in the filesystem can both get
mapped to INVALID_UID, which may result in following a symlink
when this would not have otherwise been permitted when protected
symlinks are enabled.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 10c64cea04d3c75c306b3f990586ffb343b63287 upstream.
* if we have a hashed negative dentry and either CREAT|EXCL on
r/o filesystem, or CREAT|TRUNC on r/o filesystem, or CREAT|EXCL
with failing may_o_create(), we should fail with EROFS or the
error may_o_create() has returned, but not ENOENT. Which is what
the current code ends up returning.
* if we have CREAT|TRUNC hitting a regular file on a read-only
filesystem, we can't fail with EROFS here. At the very least,
not until we'd done follow_managed() - we might have a writable
file (or a device, for that matter) bound on top of that one.
Moreover, the code downstream will see that O_TRUNC and attempt
to grab the write access (*after* following possible mount), so
if we really should fail with EROFS, it will happen. No need
to do that inside atomic_open().
The real logics is much simpler than what the current code is
trying to do - if we decided to go for simple lookup, ended
up with a negative dentry *and* had create_error set, fail with
create_error. No matter whether we'd got that negative dentry
from lookup_real() or had found it in dcache.
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9409e22acdfc9153f88d9b1ed2bd2a5b34d2d3ca upstream.
If a file is renamed to a hardlink of itself POSIX specifies that rename(2)
should do nothing and return success.
This condition is checked in vfs_rename(). However it won't detect hard
links on overlayfs where these are given separate inodes on the overlayfs
layer.
Overlayfs itself detects this condition and returns success without doing
anything, but then vfs_rename() will proceed as if this was a successful
rename (detach_mounts(), d_move()).
The correct thing to do is to detect this condition before even calling
into overlayfs. This patch does this by calling vfs_select_inode() to get
the underlying inodes.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5129fa482b16615fd4464d2f5d23acb1b7056c66 upstream.
... or we risk seeing a bogus value of d_is_symlink() there.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a7f775428b8f5808815c0e3004020cedb94cbe3b upstream.
... otherwise d_is_symlink() above might have nothing to do with
the inode value we've got.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c80567c82ae4814a41287618e315a60ecf513be6 upstream.
... into returning a positive to path_openat(), which would interpret that
as "symlink had been encountered" and proceed to corrupt memory, etc.
It can only happen due to a bug in some ->open() instance or in some LSM
hook, etc., so we report any such event *and* make sure it doesn't trick
us into further unpleasantness.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d4565649b6d6923369112758212b851adc407f0c upstream.
both do_last() and walk_component() risk picking a NULL inode out
of dentry about to become positive, *then* checking its flags and
seeing that it's not negative anymore and using (already stale by
then) value they'd fetched earlier. Usually ends up oopsing soon
after that...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
we already zero it on outermost set_nameidata(), so initialization in
path_init() is pointless and wrong. The same DoS exists on pre-4.2
kernels, but there a slightly different fix will be needed.
Cc: stable@vger.kernel.org # v4.2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Merge second patch-bomb from Andrew Morton:
- most of the rest of MM
- procfs
- lib/ updates
- printk updates
- bitops infrastructure tweaks
- checkpatch updates
- nilfs2 update
- signals
- various other misc bits: coredump, seqfile, kexec, pidns, zlib, ipc,
dma-debug, dma-mapping, ...
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (102 commits)
ipc,msg: drop dst nil validation in copy_msg
include/linux/zutil.h: fix usage example of zlib_adler32()
panic: release stale console lock to always get the logbuf printed out
dma-debug: check nents in dma_sync_sg*
dma-mapping: tidy up dma_parms default handling
pidns: fix set/getpriority and ioprio_set/get in PRIO_USER mode
kexec: use file name as the output message prefix
fs, seqfile: always allow oom killer
seq_file: reuse string_escape_str()
fs/seq_file: use seq_* helpers in seq_hex_dump()
coredump: change zap_threads() and zap_process() to use for_each_thread()
coredump: ensure all coredumping tasks have SIGNAL_GROUP_COREDUMP
signal: remove jffs2_garbage_collect_thread()->allow_signal(SIGCONT)
signal: introduce kernel_signal_stop() to fix jffs2_garbage_collect_thread()
signal: turn dequeue_signal_lock() into kernel_dequeue_signal()
signals: kill block_all_signals() and unblock_all_signals()
nilfs2: fix gcc uninitialized-variable warnings in powerpc build
nilfs2: fix gcc unused-but-set-variable warnings
MAINTAINERS: nilfs2: add header file for tracing
nilfs2: add tracepoints for analyzing reading and writing metadata files
...
Pull trivial updates from Jiri Kosina:
"Trivial stuff from trivial tree that can be trivially summed up as:
- treewide drop of spurious unlikely() before IS_ERR() from Viresh
Kumar
- cosmetic fixes (that don't really affect basic functionality of the
driver) for pktcdvd and bcache, from Julia Lawall and Petr Mladek
- various comment / printk fixes and updates all over the place"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
bcache: Really show state of work pending bit
hwmon: applesmc: fix comment typos
Kconfig: remove comment about scsi_wait_scan module
class_find_device: fix reference to argument "match"
debugfs: document that debugfs_remove*() accepts NULL and error values
net: Drop unlikely before IS_ERR(_OR_NULL)
mm: Drop unlikely before IS_ERR(_OR_NULL)
fs: Drop unlikely before IS_ERR(_OR_NULL)
drivers: net: Drop unlikely before IS_ERR(_OR_NULL)
drivers: misc: Drop unlikely before IS_ERR(_OR_NULL)
UBI: Update comments to reflect UBI_METAONLY flag
pktcdvd: drop null test before destroy functions
There are many places which use mapping_gfp_mask to restrict a more
generic gfp mask which would be used for allocations which are not
directly related to the page cache but they are performed in the same
context.
Let's introduce a helper function which makes the restriction explicit and
easier to track. This patch doesn't introduce any functional changes.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull userns hardlink capability check fix from Eric Biederman:
"This round just contains a single patch. There has been a lot of
other work this period but it is not quite ready yet, so I am pushing
it until 4.5.
The remaining change by Dirk Steinmetz wich fixes both Gentoo and
Ubuntu containers allows hardlinks if we have the appropriate
capabilities in the user namespace. Security wise it is really a
gimme as the user namespace root can already call setuid become that
user and create the hardlink"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
namei: permit linking with CAP_FOWNER in userns
Attempting to hardlink to an unsafe file (e.g. a setuid binary) from
within an unprivileged user namespace fails, even if CAP_FOWNER is held
within the namespace. This may cause various failures, such as a gentoo
installation within a lxc container failing to build and install specific
packages.
This change permits hardlinking of files owned by mapped uids, if
CAP_FOWNER is held for that namespace. Furthermore, it improves consistency
by using the existing inode_owner_or_capable(), which is aware of
namespaced capabilities as of 23adbe12ef ("fs,userns: Change
inode_capable to capable_wrt_inode_uidgid").
Signed-off-by: Dirk Steinmetz <public@rsjtdrjgfuzkfg.com>
This is hitting us in Ubuntu during some dpkg upgrades in containers.
When upgrading a file dpkg creates a hard link to the old file to back
it up before overwriting it. When packages upgrade suid files owned by a
non-root user the link isn't permitted, and the package upgrade fails.
This patch fixes our problem.
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Leandro Awa writes:
"After switching to version 4.1.6, our parallelized and distributed
workflows now fail consistently with errors of the form:
T34: ./regex.c:39:22: error: config.h: No such file or directory
From our 'git bisect' testing, the following commit appears to be the
possible cause of the behavior we've been seeing: commit 766c4cbfacd8"
Al Viro says:
"What happens is that 766c4cbfac got the things subtly wrong.
We used to treat d_is_negative() after lookup_fast() as "fall with
ENOENT". That was wrong - checking ->d_flags outside of ->d_seq
protection is unreliable and failing with hard error on what should've
fallen back to non-RCU pathname resolution is a bug.
Unfortunately, we'd pulled the test too far up and ran afoul of
another kind of staleness. The dentry might have been absolutely
stable from the RCU point of view (and we might be on UP, etc), but
stale from the remote fs point of view. If ->d_revalidate() returns
"it's actually stale", dentry gets thrown away and the original code
wouldn't even have looked at its ->d_flags.
What we need is to check ->d_flags where 766c4cbfac does (prior to
->d_seq validation) but only use the result in cases where we do not
discard this dentry outright"
Reported-by: Leandro Awa <lawa@nvidia.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=104911
Fixes: 766c4cbfac ("namei: d_is_negative() should be checked...")
Tested-by: Leandro Awa <lawa@nvidia.com>
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
IS_ERR(_OR_NULL) already contain an 'unlikely' compiler flag and there
is no need to do that again from its callers. Drop it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steve French <smfrench@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Fix the following warnings:
Warning(.//fs/namei.c:2422): No description found for parameter 'nd'
Warning(.//fs/namei.c:2422): Excess function parameter 'nameidata'
description in 'path_mountpoint'
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In rare cases a directory can be renamed out from under a bind mount.
In those cases without special handling it becomes possible to walk up
the directory tree to the root dentry of the filesystem and down
from the root dentry to every other file or directory on the filesystem.
Like division by zero .. from an unconnected path can not be given
a useful semantic as there is no predicting at which path component
the code will realize it is unconnected. We certainly can not match
the current behavior as the current behavior is a security hole.
Therefore when encounting .. when following an unconnected path
return -ENOENT.
- Add a function path_connected to verify path->dentry is reachable
from path->mnt.mnt_root. AKA to validate that rename did not do
something nasty to the bind mount.
To avoid races path_connected must be called after following a path
component to it's next path component.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now that we can get there in RCU mode, we shouldn't play with
nd->path.dentry->d_inode - it's not guaranteed to be stable.
Use nd->inode instead.
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In RCU mode we might end up with dentry evicted just we check
that it's a directory. In such case we should return ECHILD
rather than ENOTDIR, so that pathwalk would be retries in non-RCU
mode.
Breakage had been introduced in commit b18825a - prior to that
we were looking at nd->inode, which had been fetched before
verifying that ->d_seq was still valid. That form of check
would only be satisfied if at some point the pathname prefix
would indeed have resolved to a non-directory. The fix consists
of checking ->d_seq after we'd run into a non-directory dentry,
and failing with ECHILD in case of mismatch.
Note that all branches since 3.12 have that problem...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The only caller that cares about its return value can just
as easily pick it from nd->root_seq itself. We used to just
calculate it and return to caller, but these days we are
storing it in nd->root_seq in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
these guys are always declared next to each other; might as well put
the former (pointer to previous instance) into the latter and simplify
the calling conventions for {set,restore}_nameidata()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
a) make it reject ERR_PTR() for name
b) make it putname(name) on all other failure exits
c) make it return name on success
again, simplifies the callers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
a) make it reject ERR_PTR() for name
b) make it putname(name) upon return in all other cases.
seriously simplifies the callers...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Otherwise we are risking a hard error where nonlazy restart would be the right
thing to do; it's a very narrow race with mount --move and most of the time it
ends up being completely harmless, but it's possible to construct a case when
we'll get a bogus hard error instead of falling back to non-lazy walk...
For one thing, when crossing _into_ overmount of parent we need to check for
mount_lock bumps when we get NULL from __lookup_mnt() as well.
For another, and less exotically, we need to make sure that the data fetched
in follow_up_rcu() had been consistent. ->mnt_mountpoint is pinned for as
long as it is a mountpoint, but we need to check mount_lock after fetching
to verify that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
