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2017-03-23Merge tag v4.4.55 into branch 'msm-4.4'Blagovest Kolenichev
refs/heads/tmp-28ec98b: Linux 4.4.55 ext4: don't BUG when truncating encrypted inodes on the orphan list dm: flush queued bios when process blocks to avoid deadlock nfit, libnvdimm: fix interleave set cookie calculation s390/kdump: Use "LINUX" ELF note name instead of "CORE" KVM: s390: Fix guest migration for huge guests resulting in panic mvsas: fix misleading indentation serial: samsung: Continue to work if DMA request fails USB: serial: io_ti: fix information leak in completion handler USB: serial: io_ti: fix NULL-deref in interrupt callback USB: iowarrior: fix NULL-deref in write USB: iowarrior: fix NULL-deref at probe USB: serial: omninet: fix reference leaks at open USB: serial: safe_serial: fix information leak in completion handler usb: host: xhci-plat: Fix timeout on removal of hot pluggable xhci controllers usb: host: xhci-dbg: HCIVERSION should be a binary number usb: gadget: function: f_fs: pass companion descriptor along usb: dwc3: gadget: make Set Endpoint Configuration macros safe usb: gadget: dummy_hcd: clear usb_gadget region before registration powerpc: Emulation support for load/store instructions on LE tracing: Add #undef to fix compile error MIPS: Netlogic: Fix CP0_EBASE redefinition warnings MIPS: DEC: Avoid la pseudo-instruction in delay slots mm: memcontrol: avoid unused function warning cpmac: remove hopeless #warning MIPS: ralink: Remove unused rt*_wdt_reset functions MIPS: ralink: Cosmetic change to prom_init(). mtd: pmcmsp: use kstrndup instead of kmalloc+strncpy MIPS: Update lemote2f_defconfig for CPU_FREQ_STAT change MIPS: ip22: Fix ip28 build for modern gcc MIPS: Update ip27_defconfig for SCSI_DH change MIPS: ip27: Disable qlge driver in defconfig MIPS: Update defconfigs for NF_CT_PROTO_DCCP/UDPLITE change crypto: improve gcc optimization flags for serpent and wp512 USB: serial: digi_acceleport: fix OOB-event processing USB: serial: digi_acceleport: fix OOB data sanity check Linux 4.4.54 drivers: hv: Turn off write permission on the hypercall page fat: fix using uninitialized fields of fat_inode/fsinfo_inode libceph: use BUG() instead of BUG_ON(1) drm/i915/dsi: Do not clear DPOUNIT_CLOCK_GATE_DISABLE from vlv_init_display_clock_gating fakelb: fix schedule while atomic drm/atomic: fix an error code in mode_fixup() drm/ttm: Make sure BOs being swapped out are cacheable drm/edid: Add EDID_QUIRK_FORCE_8BPC quirk for Rotel RSX-1058 drm/ast: Fix AST2400 POST failure without BMC FW or VBIOS drm/ast: Call open_key before enable_mmio in POST code drm/ast: Fix test for VGA enabled drm/amdgpu: add more cases to DCE11 possible crtc mask setup mac80211: flush delayed work when entering suspend xtensa: move parse_tag_fdt out of #ifdef CONFIG_BLK_DEV_INITRD pwm: pca9685: Fix period change with same duty cycle nlm: Ensure callback code also checks that the files match target: Fix NULL dereference during LUN lookup + active I/O shutdown ceph: remove req from unsafe list when unregistering it ktest: Fix child exit code processing IB/srp: Fix race conditions related to task management IB/srp: Avoid that duplicate responses trigger a kernel bug IB/IPoIB: Add destination address when re-queue packet IB/ipoib: Fix deadlock between rmmod and set_mode mnt: Tuck mounts under others instead of creating shadow/side mounts. net: mvpp2: fix DMA address calculation in mvpp2_txq_inc_put() s390: use correct input data address for setup_randomness s390: make setup_randomness work s390: TASK_SIZE for kernel threads s390/dcssblk: fix device size calculation in dcssblk_direct_access() s390/qdio: clear DSCI prior to scanning multiple input queues Bluetooth: Add another AR3012 04ca:3018 device KVM: VMX: use correct vmcs_read/write for guest segment selector/base KVM: s390: Disable dirty log retrieval for UCONTROL guests serial: 8250_pci: Add MKS Tenta SCOM-0800 and SCOM-0801 cards tty: n_hdlc: get rid of racy n_hdlc.tbuf TTY: n_hdlc, fix lockdep false positive Linux 4.4.53 scsi: lpfc: Correct WQ creation for pagesize MIPS: IP22: Fix build error due to binutils 2.25 uselessnes. MIPS: IP22: Reformat inline assembler code to modern standards. powerpc/xmon: Fix data-breakpoint dmaengine: ipu: Make sure the interrupt routine checks all interrupts. bcma: use (get|put)_device when probing/removing device driver md linear: fix a race between linear_add() and linear_congested() rtc: sun6i: Switch to the external oscillator rtc: sun6i: Add some locking NFSv4: fix getacl ERANGE for some ACL buffer sizes NFSv4: fix getacl head length estimation NFSv4: Fix memory and state leak in _nfs4_open_and_get_state nfsd: special case truncates some more nfsd: minor nfsd_setattr cleanup rtlwifi: rtl8192c-common: Fix "BUG: KASAN: rtlwifi: Fix alignment issues gfs2: Add missing rcu locking for glock lookup rdma_cm: fail iwarp accepts w/o connection params RDMA/core: Fix incorrect structure packing for booleans Drivers: hv: util: Backup: Fix a rescind processing issue Drivers: hv: util: Fcopy: Fix a rescind processing issue Drivers: hv: util: kvp: Fix a rescind processing issue hv: init percpu_list in hv_synic_alloc() hv: allocate synic pages for all present CPUs usb: gadget: udc: fsl: Add missing complete function. usb: host: xhci: plat: check hcc_params after add hcd usb: musb: da8xx: Remove CPPI 3.0 quirk and methods w1: ds2490: USB transfer buffers need to be DMAable w1: don't leak refcount on slave attach failure in w1_attach_slave_device() can: usb_8dev: Fix memory leak of priv->cmd_msg_buffer iio: pressure: mpl3115: do not rely on structure field ordering iio: pressure: mpl115: do not rely on structure field ordering arm/arm64: KVM: Enforce unconditional flush to PoC when mapping to stage-2 fuse: add missing FR_FORCE crypto: testmgr - Pad aes_ccm_enc_tv_template vector ath9k: use correct OTP register offsets for the AR9340 and AR9550 ath9k: fix race condition in enabling/disabling IRQs ath5k: drop bogus warning on drv_set_key with unsupported cipher target: Fix multi-session dynamic se_node_acl double free OOPs target: Obtain se_node_acl->acl_kref during get_initiator_node_acl samples/seccomp: fix 64-bit comparison macros ext4: return EROFS if device is r/o and journal replay is needed ext4: preserve the needs_recovery flag when the journal is aborted ext4: fix inline data error paths ext4: fix data corruption in data=journal mode ext4: trim allocation requests to group size ext4: do not polute the extents cache while shifting extents ext4: Include forgotten start block on fallocate insert range loop: fix LO_FLAGS_PARTSCAN hang block/loop: fix race between I/O and set_status jbd2: don't leak modified metadata buffers on an aborted journal Fix: Disable sys_membarrier when nohz_full is enabled sd: get disk reference in sd_check_events() scsi: use 'scsi_device_from_queue()' for scsi_dh scsi: aacraid: Reorder Adapter status check scsi: storvsc: properly set residual data length on errors scsi: storvsc: properly handle SRB_ERROR when sense message is present scsi: storvsc: use tagged SRB requests if supported by the device dm stats: fix a leaked s->histogram_boundaries array dm cache: fix corruption seen when using cache > 2TB ipc/shm: Fix shmat mmap nil-page protection mm: do not access page->mapping directly on page_endio mm: vmpressure: fix sending wrong events on underflow mm/page_alloc: fix nodes for reclaim in fast path iommu/vt-d: Tylersburg isoch identity map check is done too late. iommu/vt-d: Fix some macros that are incorrectly specified in intel-iommu regulator: Fix regulator_summary for deviceless consumers staging: rtl: fix possible NULL pointer dereference ALSA: hda - Fix micmute hotkey problem for a lenovo AIO machine ALSA: hda - Add subwoofer support for Dell Inspiron 17 7000 Gaming ALSA: seq: Fix link corruption by event error handling ALSA: ctxfi: Fallback DMA mask to 32bit ALSA: timer: Reject user params with too small ticks ALSA: hda - fix Lewisburg audio issue ALSA: hda/realtek - Cannot adjust speaker's volume on a Dell AIO ARM: dts: at91: Enable DMA on sama5d2_xplained console ARM: dts: at91: Enable DMA on sama5d4_xplained console ARM: at91: define LPDDR types media: fix dm1105.c build error uvcvideo: Fix a wrong macro am437x-vpfe: always assign bpp variable MIPS: Handle microMIPS jumps in the same way as MIPS32/MIPS64 jumps MIPS: Calculate microMIPS ra properly when unwinding the stack MIPS: Fix is_jump_ins() handling of 16b microMIPS instructions MIPS: Fix get_frame_info() handling of microMIPS function size MIPS: Prevent unaligned accesses during stack unwinding MIPS: Clear ISA bit correctly in get_frame_info() MIPS: Lantiq: Keep ethernet enabled during boot MIPS: OCTEON: Fix copy_from_user fault handling for large buffers MIPS: BCM47XX: Fix button inversion for Asus WL-500W MIPS: Fix special case in 64 bit IP checksumming. samples: move mic/mpssd example code from Documentation Linux 4.4.52 kvm: vmx: ensure VMCS is current while enabling PML Revert "usb: chipidea: imx: enable CI_HDRC_SET_NON_ZERO_TTHA" rtlwifi: rtl_usb: Fix for URB leaking when doing ifconfig up/down block: fix double-free in the failure path of cgwb_bdi_init() goldfish: Sanitize the broken interrupt handler x86/platform/goldfish: Prevent unconditional loading USB: serial: ark3116: fix register-accessor error handling USB: serial: opticon: fix CTS retrieval at open USB: serial: spcp8x5: fix modem-status handling USB: serial: ftdi_sio: fix line-status over-reporting USB: serial: ftdi_sio: fix extreme low-latency setting USB: serial: ftdi_sio: fix modem-status error handling USB: serial: cp210x: add new IDs for GE Bx50v3 boards USB: serial: mos7840: fix another NULL-deref at open tty: serial: msm: Fix module autoload net: socket: fix recvmmsg not returning error from sock_error ip: fix IP_CHECKSUM handling irda: Fix lockdep annotations in hashbin_delete(). dccp: fix freeing skb too early for IPV6_RECVPKTINFO packet: Do not call fanout_release from atomic contexts packet: fix races in fanout_add() net/llc: avoid BUG_ON() in skb_orphan() blk-mq: really fix plug list flushing for nomerge queues rtc: interface: ignore expired timers when enqueuing new timers rtlwifi: rtl_usb: Fix missing entry in USB driver's private data Linux 4.4.51 mmc: core: fix multi-bit bus width without high-speed mode bcache: Make gc wakeup sane, remove set_task_state() ntb_transport: Pick an unused queue NTB: ntb_transport: fix debugfs_remove_recursive printk: use rcuidle console tracepoint ARM: 8658/1: uaccess: fix zeroing of 64-bit get_user() futex: Move futex_init() to core_initcall drm/dp/mst: fix kernel oops when turning off secondary monitor drm/radeon: Use mode h/vdisplay fields to hide out of bounds HW cursor Input: elan_i2c - add ELAN0605 to the ACPI table Fix missing sanity check in /dev/sg scsi: don't BUG_ON() empty DMA transfers fuse: fix use after free issue in fuse_dev_do_read() siano: make it work again with CONFIG_VMAP_STACK vfs: fix uninitialized flags in splice_to_pipe() Linux 4.4.50 l2tp: do not use udp_ioctl() ping: fix a null pointer dereference packet: round up linear to header len net: introduce device min_header_len sit: fix a double free on error path sctp: avoid BUG_ON on sctp_wait_for_sndbuf mlx4: Invoke softirqs after napi_reschedule macvtap: read vnet_hdr_size once tun: read vnet_hdr_sz once tcp: avoid infinite loop in tcp_splice_read() ipv6: tcp: add a missing tcp_v6_restore_cb() ip6_gre: fix ip6gre_err() invalid reads netlabel: out of bound access in cipso_v4_validate() ipv4: keep skb->dst around in presence of IP options net: use a work queue to defer net_disable_timestamp() work tcp: fix 0 divide in __tcp_select_window() ipv6: pointer math error in ip6_tnl_parse_tlv_enc_lim() ipv6: fix ip6_tnl_parse_tlv_enc_lim() can: Fix kernel panic at security_sock_rcv_skb Conflicts: drivers/scsi/sd.c drivers/usb/gadget/function/f_fs.c drivers/usb/host/xhci-plat.c CRs-Fixed: 2023471 Change-Id: I396051a8de30271af77b3890d4b19787faa1c31e Signed-off-by: Blagovest Kolenichev <bkolenichev@codeaurora.org>
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>
2017-02-03ANDROID: mnt: remount should propagate to slaves of slavesDaniel Rosenberg
propagate_remount was not accounting for the slave mounts of other slave mounts, leading to some namespaces not recieving the remount information. bug:33731928 Change-Id: Idc9e8c2ed126a4143229fc23f10a959c2d0a3854 Signed-off-by: Daniel Rosenberg <drosen@google.com>
2017-02-03ANDROID: 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>
2016-05-11propogate_mnt: Handle the first propogated copy being a slaveEric W. Biederman
commit 5ec0811d30378ae104f250bfc9b3640242d81e3f upstream. When the first propgated copy was a slave the following oops would result: > BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 > IP: [<ffffffff811fba4e>] propagate_one+0xbe/0x1c0 > PGD bacd4067 PUD bac66067 PMD 0 > Oops: 0000 [#1] SMP > Modules linked in: > CPU: 1 PID: 824 Comm: mount Not tainted 4.6.0-rc5userns+ #1523 > Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 > task: ffff8800bb0a8000 ti: ffff8800bac3c000 task.ti: ffff8800bac3c000 > RIP: 0010:[<ffffffff811fba4e>] [<ffffffff811fba4e>] propagate_one+0xbe/0x1c0 > RSP: 0018:ffff8800bac3fd38 EFLAGS: 00010283 > RAX: 0000000000000000 RBX: ffff8800bb77ec00 RCX: 0000000000000010 > RDX: 0000000000000000 RSI: ffff8800bb58c000 RDI: ffff8800bb58c480 > RBP: ffff8800bac3fd48 R08: 0000000000000001 R09: 0000000000000000 > R10: 0000000000001ca1 R11: 0000000000001c9d R12: 0000000000000000 > R13: ffff8800ba713800 R14: ffff8800bac3fda0 R15: ffff8800bb77ec00 > FS: 00007f3c0cd9b7e0(0000) GS:ffff8800bfb00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000010 CR3: 00000000bb79d000 CR4: 00000000000006e0 > Stack: > ffff8800bb77ec00 0000000000000000 ffff8800bac3fd88 ffffffff811fbf85 > ffff8800bac3fd98 ffff8800bb77f080 ffff8800ba713800 ffff8800bb262b40 > 0000000000000000 0000000000000000 ffff8800bac3fdd8 ffffffff811f1da0 > Call Trace: > [<ffffffff811fbf85>] propagate_mnt+0x105/0x140 > [<ffffffff811f1da0>] attach_recursive_mnt+0x120/0x1e0 > [<ffffffff811f1ec3>] graft_tree+0x63/0x70 > [<ffffffff811f1f6b>] do_add_mount+0x9b/0x100 > [<ffffffff811f2c1a>] do_mount+0x2aa/0xdf0 > [<ffffffff8117efbe>] ? strndup_user+0x4e/0x70 > [<ffffffff811f3a45>] SyS_mount+0x75/0xc0 > [<ffffffff8100242b>] do_syscall_64+0x4b/0xa0 > [<ffffffff81988f3c>] entry_SYSCALL64_slow_path+0x25/0x25 > Code: 00 00 75 ec 48 89 0d 02 22 22 01 8b 89 10 01 00 00 48 89 05 fd 21 22 01 39 8e 10 01 00 00 0f 84 e0 00 00 00 48 8b 80 d8 00 00 00 <48> 8b 50 10 48 89 05 df 21 22 01 48 89 15 d0 21 22 01 8b 53 30 > RIP [<ffffffff811fba4e>] propagate_one+0xbe/0x1c0 > RSP <ffff8800bac3fd38> > CR2: 0000000000000010 > ---[ end trace 2725ecd95164f217 ]--- This oops happens with the namespace_sem held and can be triggered by non-root users. An all around not pleasant experience. To avoid this scenario when finding the appropriate source mount to copy stop the walk up the mnt_master chain when the first source mount is encountered. Further rewrite the walk up the last_source mnt_master chain so that it is clear what is going on. The reason why the first source mount is special is that it it's mnt_parent is not a mount in the dest_mnt propagation tree, and as such termination conditions based up on the dest_mnt mount propgation tree do not make sense. To avoid other kinds of confusion last_dest is not changed when computing last_source. last_dest is only used once in propagate_one and that is above the point of the code being modified, so changing the global variable is meaningless and confusing. fixes: f2ebb3a921c1ca1e2ddd9242e95a1989a50c4c68 ("smarter propagate_mnt()") Reported-by: Tycho Andersen <tycho.andersen@canonical.com> Reviewed-by: Seth Forshee <seth.forshee@canonical.com> Tested-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>
2016-05-11fs/pnode.c: treat zero mnt_group_id-s as unequalMaxim Patlasov
commit 7ae8fd0351f912b075149a1e03a017be8b903b9a upstream. propagate_one(m) calculates "type" argument for copy_tree() like this: > if (m->mnt_group_id == last_dest->mnt_group_id) { > type = CL_MAKE_SHARED; > } else { > type = CL_SLAVE; > if (IS_MNT_SHARED(m)) > type |= CL_MAKE_SHARED; > } The "type" argument then governs clone_mnt() behavior with respect to flags and mnt_master of new mount. When we iterate through a slave group, it is possible that both current "m" and "last_dest" are not shared (although, both are slaves, i.e. have non-NULL mnt_master-s). Then the comparison above erroneously makes new mount shared and sets its mnt_master to last_source->mnt_master. The patch fixes the problem by handling zero mnt_group_id-s as though they are unequal. The similar problem exists in the implementation of "else" clause above when we have to ascend upward in the master/slave tree by calling: > last_source = last_source->mnt_master; > last_dest = last_source->mnt_parent; proper number of times. The last step is governed by "n->mnt_group_id != last_dest->mnt_group_id" condition that may lie if both are zero. The patch fixes this case in the same way as the former one. [AV: don't open-code an obvious helper...] Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-02mnt: Don't propagate unmounts to locked mountsEric W. Biederman
If the first mount in shared subtree is locked don't unmount the shared subtree. This is ensured by walking through the mounts parents before children and marking a mount as unmountable if it is not locked or it is locked but it's parent is marked. This allows recursive mount detach to propagate through a set of mounts when unmounting them would not reveal what is under any locked mount. Cc: stable@vger.kernel.org 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>
2014-12-02mnt: Move the clear of MNT_LOCKED from copy_tree to it's callers.Eric W. Biederman
Clear MNT_LOCKED in the callers of copy_tree except copy_mnt_ns, and collect_mounts. In copy_mnt_ns it is necessary to create an exact copy of a mount tree, so not clearing MNT_LOCKED is important. Similarly collect_mounts is used to take a snapshot of the mount tree for audit logging purposes and auditing using a faithful copy of the tree is important. This becomes particularly significant when we start setting MNT_LOCKED on rootfs to prevent it from being unmounted. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2014-08-30get rid of propagate_umount() mistakenly treating slaves as busy.Al Viro
The check in __propagate_umount() ("has somebody explicitly mounted something on that slave?") is done *before* taking the already doomed victims out of the child lists. Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01smarter propagate_mnt()Al Viro
The current mainline has copies propagated to *all* nodes, then tears down the copies we made for nodes that do not contain counterparts of the desired mountpoint. That sets the right propagation graph for the copies (at teardown time we move the slaves of removed node to a surviving peer or directly to master), but we end up paying a fairly steep price in useless allocations. It's fairly easy to create a situation where N calls of mount(2) create exactly N bindings, with O(N^2) vfsmounts allocated and freed in process. Fortunately, it is possible to avoid those allocations/freeings. The trick is to create copies in the right order and find which one would've eventually become a master with the current algorithm. It turns out to be possible in O(nodes getting propagation) time and with no extra allocations at all. One part is that we need to make sure that eventual master will be created before its slaves, so we need to walk the propagation tree in a different order - by peer groups. And iterate through the peers before dealing with the next group. Another thing is finding the (earlier) copy that will be a master of one we are about to create; to do that we are (temporary) marking the masters of mountpoints we are attaching the copies to. Either we are in a peer of the last mountpoint we'd dealt with, or we have the following situation: we are attaching to mountpoint M, the last copy S_0 had been attached to M_0 and there are sequences S_0...S_n, M_0...M_n such that S_{i+1} is a master of S_{i}, S_{i} mounted on M{i} and we need to create a slave of the first S_{k} such that M is getting propagation from M_{k}. It means that the master of M_{k} will be among the sequence of masters of M. On the other hand, the nearest marked node in that sequence will either be the master of M_{k} or the master of M_{k-1} (the latter - in the case if M_{k-1} is a slave of something M gets propagation from, but in a wrong peer group). So we go through the sequence of masters of M until we find a marked one (P). Let N be the one before it. Then we go through the sequence of masters of S_0 until we find one (say, S) mounted on a node D that has P as master and check if D is a peer of N. If it is, S will be the master of new copy, if not - the master of S will be. That's it for the hard part; the rest is fairly simple. Iterator is in next_group(), handling of one prospective mountpoint is propagate_one(). It seems to survive all tests and gives a noticably better performance than the current mainline for setups that are seriously using shared subtrees. Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-30switch mnt_hash to hlistAl Viro
fixes RCU bug - walking through hlist is safe in face of element moves, since it's self-terminating. Cyclic lists are not - if we end up jumping to another hash chain, we'll loop infinitely without ever hitting the original list head. [fix for dumb braino folded] Spotted by: Max Kellermann <mk@cm4all.com> Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24split __lookup_mnt() in two functionsAl Viro
Instead of passing the direction as argument (and checking it on every step through the hash chain), just have separate __lookup_mnt() and __lookup_mnt_last(). And use the standard iterators... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24new helpers: lock_mount_hash/unlock_mount_hashAl Viro
aka br_write_{lock,unlock} of vfsmount_lock. Inlines in fs/mount.h, vfsmount_lock extern moved over there as well. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24namespace.c: get rid of mnt_ghostsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-31vfs: Fix invalid ida_remove() callTakashi Iwai
When the group id of a shared mount is not allocated, the umount still tries to call mnt_release_group_id(), which eventually hits a kernel warning at ida_remove() spewing a message like: ida_remove called for id=0 which is not allocated. This patch fixes the bug simply checking the group id in the caller. Reported-by: Cristian Rodríguez <crrodriguez@opensuse.org> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull VFS updates from Al Viro, Misc cleanups all over the place, mainly wrt /proc interfaces (switch create_proc_entry to proc_create(), get rid of the deprecated create_proc_read_entry() in favor of using proc_create_data() and seq_file etc). 7kloc removed. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits) don't bother with deferred freeing of fdtables proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h proc: Make the PROC_I() and PDE() macros internal to procfs proc: Supply a function to remove a proc entry by PDE take cgroup_open() and cpuset_open() to fs/proc/base.c ppc: Clean up scanlog ppc: Clean up rtas_flash driver somewhat hostap: proc: Use remove_proc_subtree() drm: proc: Use remove_proc_subtree() drm: proc: Use minor->index to label things, not PDE->name drm: Constify drm_proc_list[] zoran: Don't print proc_dir_entry data in debug reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show() proc: Supply an accessor for getting the data from a PDE's parent airo: Use remove_proc_subtree() rtl8192u: Don't need to save device proc dir PDE rtl8187se: Use a dir under /proc/net/r8180/ proc: Add proc_mkdir_data() proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h} proc: Move PDE_NET() to fs/proc/proc_net.c ...
2013-04-09switch unlock_mount() to namespace_unlock(), convert all umount_tree() callersAl Viro
which allows to kill the last argument of umount_tree() and make release_mounts() static. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-09get rid of full-hash scan on detaching vfsmountsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-27vfs: Carefully propogate mounts across user namespacesEric W. Biederman
As a matter of policy MNT_READONLY should not be changable if the original mounter had more privileges than creator of the mount namespace. Add the flag CL_UNPRIVILEGED to note when we are copying a mount from a mount namespace that requires more privileges to a mount namespace that requires fewer privileges. When the CL_UNPRIVILEGED flag is set cause clone_mnt to set MNT_NO_REMOUNT if any of the mnt flags that should never be changed are set. This protects both mount propagation and the initial creation of a less privileged mount namespace. Cc: stable@vger.kernel.org Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-07-14VFS: Make clone_mnt()/copy_tree()/collect_mounts() return errorsDavid Howells
copy_tree() can theoretically fail in a case other than ENOMEM, but always returns NULL which is interpreted by callers as -ENOMEM. Change it to return an explicit error. Also change clone_mnt() for consistency and because union mounts will add new error cases. Thanks to Andreas Gruenbacher <agruen@suse.de> for a bug fix. [AV: folded braino fix by Dan Carpenter] Original-author: Valerie Aurora <vaurora@redhat.com> Signed-off-by: David Howells <dhowells@redhat.com> Cc: Valerie Aurora <valerie.aurora@gmail.com> Cc: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-29brlocks/lglocks: API cleanupsAndi Kleen
lglocks and brlocks are currently generated with some complicated macros in lglock.h. But there's no reason to not just use common utility functions and put all the data into a common data structure. In preparation, this patch changes the API to look more like normal function calls with pointers, not magic macros. The patch is rather large because I move over all users in one go to keep it bisectable. This impacts the VFS somewhat in terms of lines changed. But no actual behaviour change. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: switch pnode.h macros to struct mount *Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: move the rest of int fields to struct mountAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: mnt_id/mnt_group_id movedAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: mnt_ns moved to struct mountAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: take mnt_share/mnt_slave/mnt_slave_list and mnt_expire to struct mountAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: and now we can make ->mnt_master point to struct mountAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: take mnt_master to struct mountAl Viro
make IS_MNT_SLAVE take struct mount * at the same time Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - remaining argument of mnt_set_mountpoint()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - propagate_mnt()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - shared subtree iteratorsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - get_dominating_id / do_make_slaveAl Viro
next pile of horrors, similar to mnt_parent one; this time it's mnt_master. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: take mnt_child/mnt_mounts to struct mountAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - work with countersAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: move mnt_mountpoint to struct mountAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: now it can be done - make mnt_parent point to struct mountAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: mnt_parent moved to struct mountAl Viro
the second victim... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - is_path_reachableAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - do_umount/propagate_mount_busyAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount mnt_set_mountpoint child argumentAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - clone_mnt/copy_tree argumentAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - umount_tree argumentAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: the first spoils - mnt_hash movedAl Viro
taken out of struct vfsmount into struct mount Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - clone_mnt/copy_tree resultAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - change_mnt_propagation/set_mnt_sharedAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03vfs: spread struct mount - mount group id handlingAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>