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2018-04-24Merge android-4.4.129 (b1c4836) into msm-4.4Srinivasarao P
* refs/heads/tmp-b1c4836 Linux 4.4.129 writeback: safer lock nesting fanotify: fix logic of events on child ext4: bugfix for mmaped pages in mpage_release_unused_pages() mm/filemap.c: fix NULL pointer in page_cache_tree_insert() mm: allow GFP_{FS,IO} for page_cache_read page cache allocation autofs: mount point create should honour passed in mode Don't leak MNT_INTERNAL away from internal mounts rpc_pipefs: fix double-dput() hypfs_kill_super(): deal with failed allocations jffs2_kill_sb(): deal with failed allocations powerpc/lib: Fix off-by-one in alternate feature patching powerpc/eeh: Fix enabling bridge MMIO windows MIPS: memset.S: Fix clobber of v1 in last_fixup MIPS: memset.S: Fix return of __clear_user from Lpartial_fixup MIPS: memset.S: EVA & fault support for small_memset MIPS: uaccess: Add micromips clobbers to bzero invocation HID: hidraw: Fix crash on HIDIOCGFEATURE with a destroyed device ALSA: hda - New VIA controller suppor no-snoop path ALSA: rawmidi: Fix missing input substream checks in compat ioctls ALSA: line6: Use correct endpoint type for midi output ext4: fix deadlock between inline_data and ext4_expand_extra_isize_ea() ext4: fix crashes in dioread_nolock mode drm/radeon: Fix PCIe lane width calculation ext4: don't allow r/w mounts if metadata blocks overlap the superblock vfio/pci: Virtualize Maximum Read Request Size vfio/pci: Virtualize Maximum Payload Size vfio-pci: Virtualize PCIe & AF FLR ALSA: pcm: Fix endless loop for XRUN recovery in OSS emulation ALSA: pcm: Fix mutex unbalance in OSS emulation ioctls ALSA: pcm: Return -EBUSY for OSS ioctls changing busy streams ALSA: pcm: Avoid potential races between OSS ioctls and read/write ALSA: pcm: Use ERESTARTSYS instead of EINTR in OSS emulation ALSA: oss: consolidate kmalloc/memset 0 call to kzalloc watchdog: f71808e_wdt: Fix WD_EN register read thermal: imx: Fix race condition in imx_thermal_probe() clk: bcm2835: De-assert/assert PLL reset signal when appropriate clk: mvebu: armada-38x: add support for missing clocks clk: mvebu: armada-38x: add support for 1866MHz variants mmc: jz4740: Fix race condition in IRQ mask update iommu/vt-d: Fix a potential memory leak um: Use POSIX ucontext_t instead of struct ucontext dmaengine: at_xdmac: fix rare residue corruption IB/srp: Fix completion vector assignment algorithm IB/srp: Fix srp_abort() ALSA: pcm: Fix UAF at PCM release via PCM timer access RDMA/ucma: Don't allow setting RDMA_OPTION_IB_PATH without an RDMA device ext4: fail ext4_iget for root directory if unallocated ext4: don't update checksum of new initialized bitmaps jbd2: if the journal is aborted then don't allow update of the log tail random: use a tighter cap in credit_entropy_bits_safe() thunderbolt: Resume control channel after hibernation image is created ASoC: ssm2602: Replace reg_default_raw with reg_default HID: core: Fix size as type u32 HID: Fix hid_report_len usage powerpc/powernv: Fix OPAL NVRAM driver OPAL_BUSY loops powerpc/powernv: define a standard delay for OPAL_BUSY type retry loops powerpc/64: Fix smp_wmb barrier definition use use lwsync consistently powerpc/powernv: Handle unknown OPAL errors in opal_nvram_write() HID: i2c-hid: fix size check and type usage usb: dwc3: pci: Properly cleanup resource USB:fix USB3 devices behind USB3 hubs not resuming at hibernate thaw ACPI / hotplug / PCI: Check presence of slot itself in get_slot_status() ACPI / video: Add quirk to force acpi-video backlight on Samsung 670Z5E regmap: Fix reversed bounds check in regmap_raw_write() xen-netfront: Fix hang on device removal ARM: dts: at91: sama5d4: fix pinctrl compatible string ARM: dts: at91: at91sam9g25: fix mux-mask pinctrl property usb: musb: gadget: misplaced out of bounds check mm, slab: reschedule cache_reap() on the same CPU ipc/shm: fix use-after-free of shm file via remap_file_pages() resource: fix integer overflow at reallocation fs/reiserfs/journal.c: add missing resierfs_warning() arg ubi: Reject MLC NAND ubi: Fix error for write access ubi: fastmap: Don't flush fastmap work on detach ubifs: Check ubifs_wbuf_sync() return code tty: make n_tty_read() always abort if hangup is in progress x86/hweight: Don't clobber %rdi x86/hweight: Get rid of the special calling convention lan78xx: Correctly indicate invalid OTP slip: Check if rstate is initialized before uncompressing cdc_ether: flag the Cinterion AHS8 modem by gemalto as WWAN hwmon: (ina2xx) Fix access to uninitialized mutex rtl8187: Fix NULL pointer dereference in priv->conf_mutex getname_kernel() needs to make sure that ->name != ->iname in long case s390/ipl: ensure loadparm valid flag is set s390/qdio: don't merge ERROR output buffers s390/qdio: don't retry EQBS after CCQ 96 block/loop: fix deadlock after loop_set_status Revert "perf tests: Decompress kernel module before objdump" radeon: hide pointless #warning when compile testing perf intel-pt: Fix timestamp following overflow perf intel-pt: Fix error recovery from missing TIP packet perf intel-pt: Fix sync_switch perf intel-pt: Fix overlap detection to identify consecutive buffers correctly parisc: Fix out of array access in match_pci_device() media: v4l2-compat-ioctl32: don't oops on overlay f2fs: check cap_resource only for data blocks Revert "f2fs: introduce f2fs_set_page_dirty_nobuffer" f2fs: clear PageError on writepage UPSTREAM: timer: Export destroy_hrtimer_on_stack() BACKPORT: dm verity: add 'check_at_most_once' option to only validate hashes once f2fs: call unlock_new_inode() before d_instantiate() f2fs: refactor read path to allow multiple postprocessing steps fscrypt: allow synchronous bio decryption Change-Id: I45f4ac10734d92023b53118d83dcd6c83974a283 Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
2018-04-24Merge 4.4.129 into android-4.4Greg Kroah-Hartman
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>
2018-04-24Don't leak MNT_INTERNAL away from internal mountsAl Viro
commit 16a34adb9392b2fe4195267475ab5b472e55292c upstream. We want it only for the stuff created by SB_KERNMOUNT mounts, *not* for their copies. As it is, creating a deep stack of bindings of /proc/*/ns/* somewhere in a new namespace and exiting yields a stack overflow. Cc: stable@kernel.org Reported-by: Alexander Aring <aring@mojatatu.com> Bisected-by: Kirill Tkhai <ktkhai@virtuozzo.com> Tested-by: Kirill Tkhai <ktkhai@virtuozzo.com> Tested-by: Alexander Aring <aring@mojatatu.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-21Merge android-4.4@29d0b65 (v4.4.88) into msm-4.4Blagovest Kolenichev
* refs/heads/tmp-29d0b65 Linux 4.4.88 xfs: XFS_IS_REALTIME_INODE() should be false if no rt device present NFS: Fix 2 use after free issues in the I/O code ARM: 8692/1: mm: abort uaccess retries upon fatal signal Bluetooth: Properly check L2CAP config option output buffer length ALSA: msnd: Optimize / harden DSP and MIDI loops locktorture: Fix potential memory leak with rw lock test btrfs: resume qgroup rescan on rw remount drm/bridge: adv7511: Re-write the i2c address before EDID probing drm/bridge: adv7511: Switch to using drm_kms_helper_hotplug_event() drm/bridge: adv7511: Use work_struct to defer hotplug handing to out of irq context drm/bridge: adv7511: Fix mutex deadlock when interrupts are disabled drm: adv7511: really enable interrupts for EDID detection scsi: sg: recheck MMAP_IO request length with lock held scsi: sg: protect against races between mmap() and SG_SET_RESERVED_SIZE cs5536: add support for IDE controller variant workqueue: Fix flag collision drm/nouveau/pci/msi: disable MSI on big-endian platforms by default mwifiex: correct channel stat buffer overflows dlm: avoid double-free on error path in dlm_device_{register,unregister} Bluetooth: Add support of 13d3:3494 RTL8723BE device rtlwifi: rtl_pci_probe: Fix fail path of _rtl_pci_find_adapter Input: trackpoint - assume 3 buttons when buttons detection fails ath10k: fix memory leak in rx ring buffer allocation intel_th: pci: Add Cannon Lake PCH-LP support intel_th: pci: Add Cannon Lake PCH-H support driver core: bus: Fix a potential double free staging/rts5208: fix incorrect shift to extract upper nybble USB: core: Avoid race of async_completed() w/ usbdev_release() usb:xhci:Fix regression when ATI chipsets detected usb: Add device quirk for Logitech HD Pro Webcam C920-C USB: serial: option: add support for D-Link DWM-157 C1 usb: quirks: add delay init quirk for Corsair Strafe RGB keyboard ANDROID: sdcardfs: Add missing break ANDROID: Sdcardfs: Move gid derivation under flag ANDROID: mnt: Fix freeing of mount data drivers: cpufreq: checks to avoid kernel crash in cpufreq_interactive ANDROID: Use sk_uid to replace uid get from socket file ANDROID: nf: xt_qtaguid: fix handling for cases where tunnels are used. Revert "ANDROID: Use sk_uid to replace uid get from socket file" ANDROID: fiq_debugger: Fix minor bug in code Conflicts: drivers/cpufreq/cpufreq_interactive.c drivers/net/wireless/ath/ath10k/core.c drivers/staging/android/fiq_debugger/fiq_debugger.c net/netfilter/xt_qtaguid.c Change-Id: I49c67ff84d4bee0799691cc1ee0a023e2dd13e66 Signed-off-by: Blagovest Kolenichev <bkolenichev@codeaurora.org>
2017-09-08ANDROID: mnt: Fix freeing of mount dataDaniel Rosenberg
Fix double free on error paths Signed-off-by: Daniel Rosenberg <drosen@google.com> Change-Id: I1c25a175e87e5dd5cafcdcf9d78bf4c0dc3f88ef Bug: 65386954 Fixes: 6b42d02561d3 ("ANDROID: mnt: Add filesystem private data to mount points")
2017-08-08Merge "Merge android-4.4@59ff2e1 (v4.4.78) into msm-4.4"Linux Build Service Account
2017-07-21Merge 4.4.78 into android-4.4Greg Kroah-Hartman
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>
2017-07-21mnt: In propgate_umount handle visiting mounts in any orderEric W. Biederman
commit 99b19d16471e9c3faa85cad38abc9cbbe04c6d55 upstream. While investigating some poor umount performance I realized that in the case of overlapping mount trees where some of the mounts are locked the code has been failing to unmount all of the mounts it should have been unmounting. This failure to unmount all of the necessary mounts can be reproduced with: $ cat locked_mounts_test.sh mount -t tmpfs test-base /mnt mount --make-shared /mnt mkdir -p /mnt/b mount -t tmpfs test1 /mnt/b mount --make-shared /mnt/b mkdir -p /mnt/b/10 mount -t tmpfs test2 /mnt/b/10 mount --make-shared /mnt/b/10 mkdir -p /mnt/b/10/20 mount --rbind /mnt/b /mnt/b/10/20 unshare -Urm --propagation unchaged /bin/sh -c 'sleep 5; if [ $(grep test /proc/self/mountinfo | wc -l) -eq 1 ] ; then echo SUCCESS ; else echo FAILURE ; fi' sleep 1 umount -l /mnt/b wait %% $ unshare -Urm ./locked_mounts_test.sh This failure is corrected by removing the prepass that marks mounts that may be umounted. A first pass is added that umounts mounts if possible and if not sets mount mark if they could be unmounted if they weren't locked and adds them to a list to umount possibilities. This first pass reconsiders the mounts parent if it is on the list of umount possibilities, ensuring that information of umoutability will pass from child to mount parent. A second pass then walks through all mounts that are umounted and processes their children unmounting them or marking them for reparenting. A last pass cleans up the state on the mounts that could not be umounted and if applicable reparents them to their first parent that remained mounted. While a bit longer than the old code this code is much more robust as it allows information to flow up from the leaves and down from the trunk making the order in which mounts are encountered in the umount propgation tree irrelevant. Fixes: 0c56fe31420c ("mnt: Don't propagate unmounts to locked mounts") Reviewed-by: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21mnt: In umount propagation reparent in a separate passEric W. Biederman
commit 570487d3faf2a1d8a220e6ee10f472163123d7da upstream. It was observed that in some pathlogical cases that the current code does not unmount everything it should. After investigation it was determined that the issue is that mnt_change_mntpoint can can change which mounts are available to be unmounted during mount propagation which is wrong. The trivial reproducer is: $ cat ./pathological.sh mount -t tmpfs test-base /mnt cd /mnt mkdir 1 2 1/1 mount --bind 1 1 mount --make-shared 1 mount --bind 1 2 mount --bind 1/1 1/1 mount --bind 1/1 1/1 echo grep test-base /proc/self/mountinfo umount 1/1 echo grep test-base /proc/self/mountinfo $ unshare -Urm ./pathological.sh The expected output looks like: 46 31 0:25 / /mnt rw,relatime - tmpfs test-base rw,uid=1000,gid=1000 47 46 0:25 /1 /mnt/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 48 46 0:25 /1 /mnt/2 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 49 54 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 50 53 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 51 49 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 54 47 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 53 48 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 52 50 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 46 31 0:25 / /mnt rw,relatime - tmpfs test-base rw,uid=1000,gid=1000 47 46 0:25 /1 /mnt/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 48 46 0:25 /1 /mnt/2 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 The output without the fix looks like: 46 31 0:25 / /mnt rw,relatime - tmpfs test-base rw,uid=1000,gid=1000 47 46 0:25 /1 /mnt/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 48 46 0:25 /1 /mnt/2 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 49 54 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 50 53 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 51 49 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 54 47 0:25 /1/1 /mnt/1/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 53 48 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 52 50 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 46 31 0:25 / /mnt rw,relatime - tmpfs test-base rw,uid=1000,gid=1000 47 46 0:25 /1 /mnt/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 48 46 0:25 /1 /mnt/2 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 52 48 0:25 /1/1 /mnt/2/1 rw,relatime shared:1 - tmpfs test-base rw,uid=1000,gid=1000 That last mount in the output was in the propgation tree to be unmounted but was missed because the mnt_change_mountpoint changed it's parent before the walk through the mount propagation tree observed it. Fixes: 1064f874abc0 ("mnt: Tuck mounts under others instead of creating shadow/side mounts.") Acked-by: Andrei Vagin <avagin@virtuozzo.com> Reviewed-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17vfs: Add support to debug umount failuresNikhilesh Reddy
When umount of a partition fails with EBUSY there is no indication as to what is keeping the mount point busy. Add support to print a kernel log showing what files are open on this mount point. Also add a new new config option CONFIG_FILE_TABLE_DEBUG to enable this feature. Change-Id: Id7a3f5e7291b22ffd0f265848ec0a9757f713561 Signed-off-by: Nikhilesh Reddy <reddyn@codeaurora.org> Signed-off-by: Ankit Jain <ankijain@codeaurora.org>
2017-04-30Merge 4.4.65 into android-4.4Greg Kroah-Hartman
Changes in 4.4.65: tipc: make sure IPv6 header fits in skb headroom tipc: make dist queue pernet tipc: re-enable compensation for socket receive buffer double counting tipc: correct error in node fsm tty: nozomi: avoid a harmless gcc warning hostap: avoid uninitialized variable use in hfa384x_get_rid gfs2: avoid uninitialized variable warning tipc: fix random link resets while adding a second bearer tipc: fix socket timer deadlock mnt: Add a per mount namespace limit on the number of mounts xc2028: avoid use after free netfilter: nfnetlink: correctly validate length of batch messages tipc: check minimum bearer MTU vfio/pci: Fix integer overflows, bitmask check staging/android/ion : fix a race condition in the ion driver ping: implement proper locking perf/core: Fix concurrent sys_perf_event_open() vs. 'move_group' race Linux 4.4.65 Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2017-04-30mnt: Add a per mount namespace limit on the number of mountsEric W. Biederman
commit d29216842a85c7970c536108e093963f02714498 upstream. CAI Qian <caiqian@redhat.com> pointed out that the semantics of shared subtrees make it possible to create an exponentially increasing number of mounts in a mount namespace. mkdir /tmp/1 /tmp/2 mount --make-rshared / for i in $(seq 1 20) ; do mount --bind /tmp/1 /tmp/2 ; done Will create create 2^20 or 1048576 mounts, which is a practical problem as some people have managed to hit this by accident. As such CVE-2016-6213 was assigned. Ian Kent <raven@themaw.net> described the situation for autofs users as follows: > The number of mounts for direct mount maps is usually not very large because of > the way they are implemented, large direct mount maps can have performance > problems. There can be anywhere from a few (likely case a few hundred) to less > than 10000, plus mounts that have been triggered and not yet expired. > > Indirect mounts have one autofs mount at the root plus the number of mounts that > have been triggered and not yet expired. > > The number of autofs indirect map entries can range from a few to the common > case of several thousand and in rare cases up to between 30000 and 50000. I've > not heard of people with maps larger than 50000 entries. > > The larger the number of map entries the greater the possibility for a large > number of active mounts so it's not hard to expect cases of a 1000 or somewhat > more active mounts. So I am setting the default number of mounts allowed per mount namespace at 100,000. This is more than enough for any use case I know of, but small enough to quickly stop an exponential increase in mounts. Which should be perfect to catch misconfigurations and malfunctioning programs. For anyone who needs a higher limit this can be changed by writing to the new /proc/sys/fs/mount-max sysctl. Tested-by: CAI Qian <caiqian@redhat.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> [bwh: Backported to 4.4: adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-15mnt: Tuck mounts under others instead of creating shadow/side mounts.Eric W. Biederman
am: 839d42687d Change-Id: Id06d474c7f7b46c1ce05056028ca02837cacf215
2017-03-15mnt: Tuck mounts under others instead of creating shadow/side mounts.Eric W. Biederman
commit 1064f874abc0d05eeed8993815f584d847b72486 upstream. Ever since mount propagation was introduced in cases where a mount in propagated to parent mount mountpoint pair that is already in use the code has placed the new mount behind the old mount in the mount hash table. This implementation detail is problematic as it allows creating arbitrary length mount hash chains. Furthermore it invalidates the constraint maintained elsewhere in the mount code that a parent mount and a mountpoint pair will have exactly one mount upon them. Making it hard to deal with and to talk about this special case in the mount code. Modify mount propagation to notice when there is already a mount at the parent mount and mountpoint where a new mount is propagating to and place that preexisting mount on top of the new mount. Modify unmount propagation to notice when a mount that is being unmounted has another mount on top of it (and no other children), and to replace the unmounted mount with the mount on top of it. Move the MNT_UMUONT test from __lookup_mnt_last into __propagate_umount as that is the only call of __lookup_mnt_last where MNT_UMOUNT may be set on any mount visible in the mount hash table. These modifications allow: - __lookup_mnt_last to be removed. - attach_shadows to be renamed __attach_mnt and its shadow handling to be removed. - commit_tree to be simplified - copy_tree to be simplified The result is an easier to understand tree of mounts that does not allow creation of arbitrary length hash chains in the mount hash table. The result is also a very slight userspace visible difference in semantics. The following two cases now behave identically, where before order mattered: case 1: (explicit user action) B is a slave of A mount something on A/a , it will propagate to B/a and than mount something on B/a case 2: (tucked mount) B is a slave of A mount something on B/a and than mount something on A/a Histroically umount A/a would fail in case 1 and succeed in case 2. Now umount A/a succeeds in both configurations. This very small change in semantics appears if anything to be a bug fix to me and my survey of userspace leads me to believe that no programs will notice or care of this subtle semantic change. v2: Updated to mnt_change_mountpoint to not call dput or mntput and instead to decrement the counts directly. It is guaranteed that there will be other references when mnt_change_mountpoint is called so this is safe. v3: Moved put_mountpoint under mount_lock in attach_recursive_mnt As the locking in fs/namespace.c changed between v2 and v3. v4: Reworked the logic in propagate_mount_busy and __propagate_umount that detects when a mount completely covers another mount. v5: Removed unnecessary tests whose result is alwasy true in find_topper and attach_recursive_mnt. v6: Document the user space visible semantic difference. Fixes: b90fa9ae8f51 ("[PATCH] shared mount handling: bind and rbind") Tested-by: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-15Merge remote-tracking branch 'common/android-4.4' into android-4.4.yDmitry Shmidt
Change-Id: Icf907f5067fb6da5935ab0d3271df54b8d5df405
2017-01-26ANDROID: vfs: Allow filesystems to access their private mount dataDaniel Rosenberg
Now we pass the vfsmount when mounting and remounting. This allows the filesystem to actually set up the mount specific data, although we can't quite do anything with it yet. show_options is expanded to include data that lives with the mount. To avoid changing existing filesystems, these have been added as new vfs functions. Change-Id: If80670bfad9f287abb8ac22457e1b034c9697097 Signed-off-by: Daniel Rosenberg <drosen@google.com>
2017-01-26ANDROID: mnt: Add filesystem private data to mount pointsDaniel Rosenberg
This starts to add private data associated directly to mount points. The intent is to give filesystems a sense of where they have come from, as a means of letting a filesystem take different actions based on this information. Change-Id: Ie769d7b3bb2f5972afe05c1bf16cf88c91647ab2 Signed-off-by: Daniel Rosenberg <drosen@google.com>
2017-01-19mnt: Protect the mountpoint hashtable with mount_lockEric W. Biederman
commit 3895dbf8985f656675b5bde610723a29cbce3fa7 upstream. Protecting the mountpoint hashtable with namespace_sem was sufficient until a call to umount_mnt was added to mntput_no_expire. At which point it became possible for multiple calls of put_mountpoint on the same hash chain to happen on the same time. Kristen Johansen <kjlx@templeofstupid.com> reported: > This can cause a panic when simultaneous callers of put_mountpoint > attempt to free the same mountpoint. This occurs because some callers > hold the mount_hash_lock, while others hold the namespace lock. Some > even hold both. > > In this submitter's case, the panic manifested itself as a GP fault in > put_mountpoint() when it called hlist_del() and attempted to dereference > a m_hash.pprev that had been poisioned by another thread. Al Viro observed that the simple fix is to switch from using the namespace_sem to the mount_lock to protect the mountpoint hash table. I have taken Al's suggested patch moved put_mountpoint in pivot_root (instead of taking mount_lock an additional time), and have replaced new_mountpoint with get_mountpoint a function that does the hash table lookup and addition under the mount_lock. The introduction of get_mounptoint ensures that only the mount_lock is needed to manipulate the mountpoint hashtable. d_set_mounted is modified to only set DCACHE_MOUNTED if it is not already set. This allows get_mountpoint to use the setting of DCACHE_MOUNTED to ensure adding a struct mountpoint for a dentry happens exactly once. Fixes: ce07d891a089 ("mnt: Honor MNT_LOCKED when detaching mounts") Reported-by: Krister Johansen <kjlx@templeofstupid.com> Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-10namespace: update event counter when umounting a deleted dentryAndrey Ulanov
commit e06b933e6ded42384164d28a2060b7f89243b895 upstream. - m_start() in fs/namespace.c expects that ns->event is incremented each time a mount added or removed from ns->list. - umount_tree() removes items from the list but does not increment event counter, expecting that it's done before the function is called. - There are some codepaths that call umount_tree() without updating "event" counter. e.g. from __detach_mounts(). - When this happens m_start may reuse a cached mount structure that no longer belongs to ns->list (i.e. use after free which usually leads to infinite loop). This change fixes the above problem by incrementing global event counter before invoking umount_tree(). Change-Id: I622c8e84dcb9fb63542372c5dbf0178ee86bb589 Signed-off-by: Andrey Ulanov <andreyu@google.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27mnt: If fs_fully_visible fails call put_filesystem.Eric W. Biederman
commit 97c1df3e54e811aed484a036a798b4b25d002ecf upstream. Add this trivial missing error handling. Fixes: 1b852bceb0d1 ("mnt: Refactor the logic for mounting sysfs and proc in a user namespace") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27mnt: Account for MS_RDONLY in fs_fully_visibleEric W. Biederman
commit 695e9df010e40f407f4830dc11d53dce957710ba upstream. In rare cases it is possible for s_flags & MS_RDONLY to be set but MNT_READONLY to be clear. This starting combination can cause fs_fully_visible to fail to ensure that the new mount is readonly. Therefore force MNT_LOCK_READONLY in the new mount if MS_RDONLY is set on the source filesystem of the mount. In general both MS_RDONLY and MNT_READONLY are set at the same for mounts so I don't expect any programs to care. Nor do I expect MS_RDONLY to be set on proc or sysfs in the initial user namespace, which further decreases the likelyhood of problems. Which means this change should only affect system configurations by paranoid sysadmins who should welcome the additional protection as it keeps people from wriggling out of their policies. Fixes: 8c6cf9cc829f ("mnt: Modify fs_fully_visible to deal with locked ro nodev and atime") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27mnt: fs_fully_visible test the proper mount for MNT_LOCKEDEric W. Biederman
commit d71ed6c930ac7d8f88f3cef6624a7e826392d61f upstream. MNT_LOCKED implies on a child mount implies the child is locked to the parent. So while looping through the children the children should be tested (not their parent). Typically an unshare of a mount namespace locks all mounts together making both the parent and the slave as locked but there are a few corner cases where other things work. Fixes: ceeb0e5d39fc ("vfs: Ignore unlocked mounts in fs_fully_visible") Reported-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace updates from Eric Biederman: "This finishes up the changes to ensure proc and sysfs do not start implementing executable files, as the there are application today that are only secure because such files do not exist. It akso fixes a long standing misfeature of /proc/<pid>/mountinfo that did not show the proper source for files bind mounted from /proc/<pid>/ns/*. It also straightens out the handling of clone flags related to user namespaces, fixing an unnecessary failure of unshare(CLONE_NEWUSER) when files such as /proc/<pid>/environ are read while <pid> is calling unshare. This winds up fixing a minor bug in unshare flag handling that dates back to the first version of unshare in the kernel. Finally, this fixes a minor regression caused by the introduction of sysfs_create_mount_point, which broke someone's in house application, by restoring the size of /sys/fs/cgroup to 0 bytes. Apparently that application uses the directory size to determine if a tmpfs is mounted on /sys/fs/cgroup. The bind mount escape fixes are present in Al Viros for-next branch. and I expect them to come from there. The bind mount escape is the last of the user namespace related security bugs that I am aware of" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: fs: Set the size of empty dirs to 0. userns,pidns: Force thread group sharing, not signal handler sharing. unshare: Unsharing a thread does not require unsharing a vm nsfs: Add a show_path method to fix mountinfo mnt: fs_fully_visible enforce noexec and nosuid if !SB_I_NOEXEC vfs: Commit to never having exectuables on proc and sysfs.
2015-07-23mnt: In detach_mounts detach the appropriate unmounted mountEric W. Biederman
The handling of in detach_mounts of unmounted but connected mounts is buggy and can lead to an infinite loop. Correct the handling of unmounted mounts in detach_mount. When the mountpoint of an unmounted but connected mount is connected to a dentry, and that dentry is deleted we need to disconnect that mount from the parent mount and the deleted dentry. Nothing changes for the unmounted and connected children. They can be safely ignored. Cc: stable@vger.kernel.org Fixes: ce07d891a0891d3c0d0c2d73d577490486b809e1 mnt: Honor MNT_LOCKED when detaching mounts Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-22mnt: Clarify and correct the disconnect logic in umount_treeEric W. Biederman
rmdir mntpoint will result in an infinite loop when there is a mount locked on the mountpoint in another mount namespace. This is because the logic to test to see if a mount should be disconnected in umount_tree is buggy. Move the logic to decide if a mount should remain connected to it's mountpoint into it's own function disconnect_mount so that clarity of expression instead of terseness of expression becomes a virtue. When the conditions where it is invalid to leave a mount connected are first ruled out, the logic for deciding if a mount should be disconnected becomes much clearer and simpler. Fixes: e0c9c0afd2fc958ffa34b697972721d81df8a56f mnt: Update detach_mounts to leave mounts connected Fixes: ce07d891a0891d3c0d0c2d73d577490486b809e1 mnt: Honor MNT_LOCKED when detaching mounts Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-10mnt: fs_fully_visible enforce noexec and nosuid if !SB_I_NOEXECEric W. Biederman
The filesystems proc and sysfs do not have executable files do not have exectuable files today and portions of userspace break if we do enforce nosuid and noexec consistency of nosuid and noexec flags between previous mounts and new mounts of proc and sysfs. Add the code to enforce consistency of the nosuid and noexec flags, and use the presence of SB_I_NOEXEC to signal that there is no need to bother. This results in a completely userspace invisible change that makes it clear fs_fully_visible can only skip the enforcement of noexec and nosuid because it is known the filesystems in question do not support executables. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-03Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace updates from Eric Biederman: "Long ago and far away when user namespaces where young it was realized that allowing fresh mounts of proc and sysfs with only user namespace permissions could violate the basic rule that only root gets to decide if proc or sysfs should be mounted at all. Some hacks were put in place to reduce the worst of the damage could be done, and the common sense rule was adopted that fresh mounts of proc and sysfs should allow no more than bind mounts of proc and sysfs. Unfortunately that rule has not been fully enforced. There are two kinds of gaps in that enforcement. Only filesystems mounted on empty directories of proc and sysfs should be ignored but the test for empty directories was insufficient. So in my tree directories on proc, sysctl and sysfs that will always be empty are created specially. Every other technique is imperfect as an ordinary directory can have entries added even after a readdir returns and shows that the directory is empty. Special creation of directories for mount points makes the code in the kernel a smidge clearer about it's purpose. I asked container developers from the various container projects to help test this and no holes were found in the set of mount points on proc and sysfs that are created specially. This set of changes also starts enforcing the mount flags of fresh mounts of proc and sysfs are consistent with the existing mount of proc and sysfs. I expected this to be the boring part of the work but unfortunately unprivileged userspace winds up mounting fresh copies of proc and sysfs with noexec and nosuid clear when root set those flags on the previous mount of proc and sysfs. So for now only the atime, read-only and nodev attributes which userspace happens to keep consistent are enforced. Dealing with the noexec and nosuid attributes remains for another time. This set of changes also addresses an issue with how open file descriptors from /proc/<pid>/ns/* are displayed. Recently readlink of /proc/<pid>/fd has been triggering a WARN_ON that has not been meaningful since it was added (as all of the code in the kernel was converted) and is not now actively wrong. There is also a short list of issues that have not been fixed yet that I will mention briefly. It is possible to rename a directory from below to above a bind mount. At which point any directory pointers below the renamed directory can be walked up to the root directory of the filesystem. With user namespaces enabled a bind mount of the bind mount can be created allowing the user to pick a directory whose children they can rename to outside of the bind mount. This is challenging to fix and doubly so because all obvious solutions must touch code that is in the performance part of pathname resolution. As mentioned above there is also a question of how to ensure that developers by accident or with purpose do not introduce exectuable files on sysfs and proc and in doing so introduce security regressions in the current userspace that will not be immediately obvious and as such are likely to require breaking userspace in painful ways once they are recognized" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: vfs: Remove incorrect debugging WARN in prepend_path mnt: Update fs_fully_visible to test for permanently empty directories sysfs: Create mountpoints with sysfs_create_mount_point sysfs: Add support for permanently empty directories to serve as mount points. kernfs: Add support for always empty directories. proc: Allow creating permanently empty directories that serve as mount points sysctl: Allow creating permanently empty directories that serve as mountpoints. fs: Add helper functions for permanently empty directories. vfs: Ignore unlocked mounts in fs_fully_visible mnt: Modify fs_fully_visible to deal with locked ro nodev and atime mnt: Refactor the logic for mounting sysfs and proc in a user namespace
2015-07-01mnt: Update fs_fully_visible to test for permanently empty directoriesEric W. Biederman
fs_fully_visible attempts to make fresh mounts of proc and sysfs give the mounter no more access to proc and sysfs than if they could have by creating a bind mount. One aspect of proc and sysfs that makes this particularly tricky is that there are other filesystems that typically mount on top of proc and sysfs. As those filesystems are mounted on empty directories in practice it is safe to ignore them. However testing to ensure filesystems are mounted on empty directories has not been something the in kernel data structures have supported so the current test for an empty directory which checks to see if nlink <= 2 is a bit lacking. proc and sysfs have recently been modified to use the new empty_dir infrastructure to create all of their dedicated mount points. Instead of testing for S_ISDIR(inode->i_mode) && i_nlink <= 2 to see if a directory is empty, test for is_empty_dir_inode(inode). That small change guaranteess mounts found on proc and sysfs really are safe to ignore, because the directories are not only empty but nothing can ever be added to them. This guarantees there is nothing to worry about when mounting proc and sysfs. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-01vfs: Ignore unlocked mounts in fs_fully_visibleEric W. Biederman
Limit the mounts fs_fully_visible considers to locked mounts. Unlocked can always be unmounted so considering them adds hassle but no security benefit. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-06-30fs: use seq_open_private() for proc_mountsYann Droneaud
A patchset to remove support for passing pre-allocated struct seq_file to seq_open(). Such feature is undocumented and prone to error. In particular, if seq_release() is used in release handler, it will kfree() a pointer which was not allocated by seq_open(). So this patchset drops support for pre-allocated struct seq_file: it's only of use in proc_namespace.c and can be easily replaced by using seq_open_private()/seq_release_private(). Additionally, it documents the use of file->private_data to hold pointer to struct seq_file by seq_open(). This patch (of 3): Since patch described below, from v2.6.15-rc1, seq_open() could use a struct seq_file already allocated by the caller if the pointer to the structure is stored in file->private_data before calling the function. Commit 1abe77b0fc4b485927f1f798ae81a752677e1d05 Author: Al Viro <viro@zeniv.linux.org.uk> Date: Mon Nov 7 17:15:34 2005 -0500 [PATCH] allow callers of seq_open do allocation themselves Allow caller of seq_open() to kmalloc() seq_file + whatever else they want and set ->private_data to it. seq_open() will then abstain from doing allocation itself. Such behavior is only used by mounts_open_common(). In order to drop support for such uncommon feature, proc_mounts is converted to use seq_open_private(), which take care of allocating the proc_mounts structure, making it available through ->private in struct seq_file. Conversely, proc_mounts is converted to use seq_release_private(), in order to release the private structure allocated by seq_open_private(). Then, ->private is used directly instead of proc_mounts() macro to access to the proc_mounts structure. Link: http://lkml.kernel.org/r/cover.1433193673.git.ydroneaud@opteya.com Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-04mnt: Modify fs_fully_visible to deal with locked ro nodev and atimeEric W. Biederman
Ignore an existing mount if the locked readonly, nodev or atime attributes are less permissive than the desired attributes of the new mount. On success ensure the new mount locks all of the same readonly, nodev and atime attributes as the old mount. The nosuid and noexec attributes are not checked here as this change is destined for stable and enforcing those attributes causes a regression in lxc and libvirt-lxc where those applications will not start and there are no known executables on sysfs or proc and no known way to create exectuables without code modifications Cc: stable@vger.kernel.org Fixes: e51db73532955 ("userns: Better restrictions on when proc and sysfs can be mounted") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-05-13mnt: Refactor the logic for mounting sysfs and proc in a user namespaceEric W. Biederman
Fresh mounts of proc and sysfs are a very special case that works very much like a bind mount. Unfortunately the current structure can not preserve the MNT_LOCK... mount flags. Therefore refactor the logic into a form that can be modified to preserve those lock bits. Add a new filesystem flag FS_USERNS_VISIBLE that requires some mount of the filesystem be fully visible in the current mount namespace, before the filesystem may be mounted. Move the logic for calling fs_fully_visible from proc and sysfs into fs/namespace.c where it has greater access to mount namespace state. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-05-11new helper: __legitimize_mnt()Al Viro
same as legitimize_mnt(), except that it does *not* drop and regain rcu_read_lock; return values are 0 => grabbed a reference, we are fine 1 => failed, just go away -1 => failed, go away and mntput(bastard) when outside of rcu_read_lock Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-09mnt: Fix fs_fully_visible to verify the root directory is visibleEric W. Biederman
This fixes a dumb bug in fs_fully_visible that allows proc or sys to be mounted if there is a bind mount of part of /proc/ or /sys/ visible. Cc: stable@vger.kernel.org Reported-by: Eric Windisch <ewindisch@docker.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-09mnt: Update detach_mounts to leave mounts connectedEric W. Biederman
Now that it is possible to lazily unmount an entire mount tree and leave the individual mounts connected to each other add a new flag UMOUNT_CONNECTED to umount_tree to force this behavior and use this flag in detach_mounts. This closes a bug where the deletion of a file or directory could trigger an unmount and reveal data under a mount point. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-09mnt: Fix the error check in __detach_mountsEric W. Biederman
lookup_mountpoint can return either NULL or an error value. Update the test in __detach_mounts to test for an error value to avoid pathological cases causing a NULL pointer dereferences. The callers of __detach_mounts should prevent it from ever being called on an unlinked dentry but don't take any chances. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-09mnt: Honor MNT_LOCKED when detaching mountsEric W. Biederman
Modify umount(MNT_DETACH) to keep mounts in the hash table that are locked to their parent mounts, when the parent is lazily unmounted. In mntput_no_expire detach the children from the hash table, depending on mnt_pin_kill in cleanup_mnt to decrement the mnt_count of the children. In __detach_mounts if there are any mounts that have been unmounted but still are on the list of mounts of a mountpoint, remove their children from the mount hash table and those children to the unmounted list so they won't linger potentially indefinitely waiting for their final mntput, now that the mounts serve no purpose. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-09mnt: Factor umount_mnt from umount_treeEric W. Biederman
For future use factor out a function umount_mnt from umount_tree. This function unhashes a mount and remembers where the mount was mounted so that eventually when the code makes it to a sleeping context the mountpoint can be dput. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-09mnt: Factor out unhash_mnt from detach_mnt and umount_treeEric W. Biederman
Create a function unhash_mnt that contains the common code between detach_mnt and umount_tree, and use unhash_mnt in place of the common code. This add a unncessary list_del_init(mnt->mnt_child) into umount_tree but given that mnt_child is already empty this extra line is a noop. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-09mnt: Fail collect_mounts when applied to unmounted mountsEric W. Biederman
The only users of collect_mounts are in audit_tree.c In audit_trim_trees and audit_add_tree_rule the path passed into collect_mounts is generated from kern_path passed an audit_tree pathname which is guaranteed to be an absolute path. In those cases collect_mounts is obviously intended to work on mounted paths and if a race results in paths that are unmounted when collect_mounts it is reasonable to fail early. The paths passed into audit_tag_tree don't have the absolute path check. But are used to play with fsnotify and otherwise interact with the audit_trees, so again operating only on mounted paths appears reasonable. Avoid having to worry about what happens when we try and audit unmounted filesystems by restricting collect_mounts to mounts that appear in the mount tree. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02mnt: On an unmount propagate clearing of MNT_LOCKEDEric W. Biederman
A prerequisite of calling umount_tree is that the point where the tree is mounted at is valid to unmount. If we are propagating the effect of the unmount clear MNT_LOCKED in every instance where the same filesystem is mounted on the same mountpoint in the mount tree, as we know (by virtue of the fact that umount_tree was called) that it is safe to reveal what is at that mountpoint. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02mnt: Delay removal from the mount hash.Eric W. Biederman
- Modify __lookup_mnt_hash_last to ignore mounts that have MNT_UMOUNTED set. - Don't remove mounts from the mount hash table in propogate_umount - Don't remove mounts from the mount hash table in umount_tree before the entire list of mounts to be umounted is selected. - Remove mounts from the mount hash table as the last thing that happens in the case where a mount has a parent in umount_tree. Mounts without parents are not hashed (by definition). This paves the way for delaying removal from the mount hash table even farther and fixing the MNT_LOCKED vs MNT_DETACH issue. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02mnt: Add MNT_UMOUNT flagEric W. Biederman
In some instances it is necessary to know if the the unmounting process has begun on a mount. Add MNT_UMOUNT to make that reliably testable. This fix gets used in fixing locked mounts in MNT_DETACH Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02mnt: In umount_tree reuse mnt_list instead of mnt_hashEric W. Biederman
umount_tree builds a list of mounts that need to be unmounted. Utilize mnt_list for this purpose instead of mnt_hash. This begins to allow keeping a mount on the mnt_hash after it is unmounted, which is necessary for a properly functioning MNT_LOCKED implementation. The fact that mnt_list is an ordinary list makding available list_move is nice bonus. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02mnt: Don't propagate umounts in __detach_mountsEric W. Biederman
Invoking mount propagation from __detach_mounts is inefficient and wrong. It is inefficient because __detach_mounts already walks the list of mounts that where something needs to be done, and mount propagation walks some subset of those mounts again. It is actively wrong because if the dentry that is passed to __detach_mounts is not part of the path to a mount that mount should not be affected. change_mnt_propagation(p,MS_PRIVATE) modifies the mount propagation tree of a master mount so it's slaves are connected to another master if possible. Which means even removing a mount from the middle of a mount tree with __detach_mounts will not deprive any mount propagated mount events. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02mnt: Improve the umount_tree flagsEric W. Biederman
- Remove the unneeded declaration from pnode.h - Mark umount_tree static as it has no callers outside of namespace.c - Define an enumeration of umount_tree's flags. - Pass umount_tree's flags in by name This removes the magic numbers 0, 1 and 2 making the code a little clearer and makes it possible for there to be lazy unmounts that don't propagate. Which is what __detach_mounts actually wants for example. Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-04-02mnt: Use hlist_move_list in namespace_unlockEric W. Biederman
Small cleanup to make the code more readable and maintainable. Signed-off-by: Eric Biederman <ebiederm@xmission.com>
2015-02-22VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)David Howells
Convert the following where appropriate: (1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry). (2) S_ISREG(dentry->d_inode) to d_is_reg(dentry). (3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry). This is actually more complicated than it appears as some calls should be converted to d_can_lookup() instead. The difference is whether the directory in question is a real dir with a ->lookup op or whether it's a fake dir with a ->d_automount op. In some circumstances, we can subsume checks for dentry->d_inode not being NULL into this, provided we the code isn't in a filesystem that expects d_inode to be NULL if the dirent really *is* negative (ie. if we're going to use d_inode() rather than d_backing_inode() to get the inode pointer). Note that the dentry type field may be set to something other than DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS manages the fall-through from a negative dentry to a lower layer. In such a case, the dentry type of the negative union dentry is set to the same as the type of the lower dentry. However, if you know d_inode is not NULL at the call site, then you can use the d_is_xxx() functions even in a filesystem. There is one further complication: a 0,0 chardev dentry may be labelled DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE. Strictly, this was intended for special directory entry types that don't have attached inodes. The following perl+coccinelle script was used: use strict; my @callers; open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') || die "Can't grep for S_ISDIR and co. callers"; @callers = <$fd>; close($fd); unless (@callers) { print "No matches\n"; exit(0); } my @cocci = ( '@@', 'expression E;', '@@', '', '- S_ISLNK(E->d_inode->i_mode)', '+ d_is_symlink(E)', '', '@@', 'expression E;', '@@', '', '- S_ISDIR(E->d_inode->i_mode)', '+ d_is_dir(E)', '', '@@', 'expression E;', '@@', '', '- S_ISREG(E->d_inode->i_mode)', '+ d_is_reg(E)' ); my $coccifile = "tmp.sp.cocci"; open($fd, ">$coccifile") || die $coccifile; print($fd "$_\n") || die $coccifile foreach (@cocci); close($fd); foreach my $file (@callers) { chomp $file; print "Processing ", $file, "\n"; system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 || die "spatch failed"; } [AV: overlayfs parts skipped] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc VFS updates from Al Viro: "This cycle a lot of stuff sits on topical branches, so I'll be sending more or less one pull request per branch. This is the first pile; more to follow in a few. In this one are several misc commits from early in the cycle (before I went for separate branches), plus the rework of mntput/dput ordering on umount, switching to use of fs_pin instead of convoluted games in namespace_unlock()" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: switch the IO-triggering parts of umount to fs_pin new fs_pin killing logics allow attaching fs_pin to a group not associated with some superblock get rid of the second argument of acct_kill() take count and rcu_head out of fs_pin dcache: let the dentry count go down to zero without taking d_lock pull bumping refcount into ->kill() kill pin_put() mode_t whack-a-mole: chelsio file->f_path.dentry is pinned down for as long as the file is open... get rid of lustre_dump_dentry() gut proc_register() a bit kill d_validate() ncpfs: get rid of d_validate() nonsense selinuxfs: don't open-code d_genocide()
2015-02-13fs/namespace: convert devname allocation to kstrdup_constAndrzej Hajda
VFS frequently performs duplication of strings located in read-only memory section. Replacing kstrdup by kstrdup_const allows to avoid such operations. Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Mike Turquette <mturquette@linaro.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Tejun Heo <tj@kernel.org> Cc: Greg KH <greg@kroah.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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