44548 Commits

Author SHA1 Message Date
Ashish Samant
2473114981 btrfs: Fix BUG_ON condition in scrub_setup_recheck_block()
pagev array in scrub_block{} is of size SCRUB_MAX_PAGES_PER_BLOCK.
page_index should be checked with the same to trigger BUG_ON().

Signed-off-by: Ashish Samant <ashish.samant@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
Josef Bacik
e042d1ec44 Btrfs: remove BUG_ON()'s in btrfs_map_block
btrfs_map_block can go horribly wrong in the face of fs corruption, lets agree
to not be assholes and panic at any possible chance things are all fucked up.

Signed-off-by: Josef Bacik <jbacik@fb.com>
[ removed type casts ]
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
Liu Bo
3d8da67817 Btrfs: fix divide error upon chunk's stripe_len
The struct 'map_lookup' uses type int for @stripe_len, while
btrfs_chunk_stripe_len() can return a u64 value, and it may end up with
@stripe_len being undefined value and it can lead to 'divide error' in
 __btrfs_map_block().

This changes 'map_lookup' to use type u64 for stripe_len, also right now
we only use BTRFS_STRIPE_LEN for stripe_len, so this adds a valid checker for
BTRFS_STRIPE_LEN.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Reported-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ folded division fix to scrub_raid56_parity ]
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
ee17fc8005 btrfs: sysfs: protect reading label by lock
If the label setting ioctl races with sysfs label handler, we could get
mixed result in the output, part old part new. We should either get the
old or new label. The chances to hit this race are low.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
66ac9fe7ba btrfs: add check to sysfs handler of label
Add a sanity check for the fs_info as we will dereference it, similar to
what the 'store features' handler does.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
ee6111386a btrfs: add read-only check to sysfs handler of features
We don't want to trigger the change on a read-only filesystem, similar
to what the label handler does.

Signed-off-by: David Sterba <dsterba@suse.cz>
2016-05-06 15:22:49 +02:00
David Sterba
e6c11f9a46 btrfs: reuse existing variable in scrub_stripe, reduce stack usage
The key variable occupies 17 bytes, the key_start is used once, we can
simply reuse existing 'key' for that purpose. As the key is not a simple
type, compiler doest not do it on itself.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
49a3c4d9b6 btrfs: use dynamic allocation for root item in create_subvol
The size of root item is more than 400 bytes, which is quite a lot of
stack space. As we do IO from inside the subvolume ioctls, we should
keep the stack usage low in case the filesystem is on top of other
layers (NFS, device mapper, iscsi, etc).

Reviewed-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
153519559a btrfs: clone: use vmalloc only as fallback for nodesize bufer
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
2f91306a37 btrfs: send: use vmalloc only as fallback for clone_sources_tmp
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
c03d01f340 btrfs: send: use vmalloc only as fallback for clone_roots
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
e55d1153db btrfs: send: use temporary variable to store allocation size
We're going to use the argument multiple times later.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
eb5b75fe2e btrfs: send: use vmalloc only as fallback for read_buf
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
6ff48ce06b btrfs: send: use vmalloc only as fallback for send_buf
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
Anand Jain
779bf3fefa btrfs: fix lock dep warning, move scratch dev out of device_list_mutex and uuid_mutex
When the replace target fails, the target device will be taken
out of fs device list, scratch + update_dev_time and freed. However
we could do the scratch  + update_dev_time and free part after the
device has been taken out of device list, so that we don't have to
hold the device_list_mutex and uuid_mutex locks.

Reported issue:

[ 5375.718845] ======================================================
[ 5375.718846] [ INFO: possible circular locking dependency detected ]
[ 5375.718849] 4.4.5-scst31x-debug-11+ #40 Not tainted
[ 5375.718849] -------------------------------------------------------
[ 5375.718851] btrfs-health/4662 is trying to acquire lock:
[ 5375.718861]  (sb_writers){.+.+.+}, at: [<ffffffff812214f7>] __sb_start_write+0xb7/0xf0
[ 5375.718862]
[ 5375.718862] but task is already holding lock:
[ 5375.718907]  (&fs_devs->device_list_mutex){+.+.+.}, at: [<ffffffffa028263c>] btrfs_destroy_dev_replace_tgtdev+0x3c/0x150 [btrfs]
[ 5375.718907]
[ 5375.718907] which lock already depends on the new lock.
[ 5375.718907]
[ 5375.718908]
[ 5375.718908] the existing dependency chain (in reverse order) is:
[ 5375.718911]
[ 5375.718911] -> #3 (&fs_devs->device_list_mutex){+.+.+.}:
[ 5375.718917]        [<ffffffff810da4be>] lock_acquire+0xce/0x1e0
[ 5375.718921]        [<ffffffff81633949>] mutex_lock_nested+0x69/0x3c0
[ 5375.718940]        [<ffffffffa0219bf6>] btrfs_show_devname+0x36/0x210 [btrfs]
[ 5375.718945]        [<ffffffff81267079>] show_vfsmnt+0x49/0x150
[ 5375.718948]        [<ffffffff81240b07>] m_show+0x17/0x20
[ 5375.718951]        [<ffffffff81246868>] seq_read+0x2d8/0x3b0
[ 5375.718955]        [<ffffffff8121df28>] __vfs_read+0x28/0xd0
[ 5375.718959]        [<ffffffff8121e806>] vfs_read+0x86/0x130
[ 5375.718962]        [<ffffffff8121f4c9>] SyS_read+0x49/0xa0
[ 5375.718966]        [<ffffffff81637976>] entry_SYSCALL_64_fastpath+0x16/0x7a
[ 5375.718968]
[ 5375.718968] -> #2 (namespace_sem){+++++.}:
[ 5375.718971]        [<ffffffff810da4be>] lock_acquire+0xce/0x1e0
[ 5375.718974]        [<ffffffff81635199>] down_write+0x49/0x80
[ 5375.718977]        [<ffffffff81243593>] lock_mount+0x43/0x1c0
[ 5375.718979]        [<ffffffff81243c13>] do_add_mount+0x23/0xd0
[ 5375.718982]        [<ffffffff81244afb>] do_mount+0x27b/0xe30
[ 5375.718985]        [<ffffffff812459dc>] SyS_mount+0x8c/0xd0
[ 5375.718988]        [<ffffffff81637976>] entry_SYSCALL_64_fastpath+0x16/0x7a
[ 5375.718991]
[ 5375.718991] -> #1 (&sb->s_type->i_mutex_key#5){+.+.+.}:
[ 5375.718994]        [<ffffffff810da4be>] lock_acquire+0xce/0x1e0
[ 5375.718996]        [<ffffffff81633949>] mutex_lock_nested+0x69/0x3c0
[ 5375.719001]        [<ffffffff8122d608>] path_openat+0x468/0x1360
[ 5375.719004]        [<ffffffff8122f86e>] do_filp_open+0x7e/0xe0
[ 5375.719007]        [<ffffffff8121da7b>] do_sys_open+0x12b/0x210
[ 5375.719010]        [<ffffffff8121db7e>] SyS_open+0x1e/0x20
[ 5375.719013]        [<ffffffff81637976>] entry_SYSCALL_64_fastpath+0x16/0x7a
[ 5375.719015]
[ 5375.719015] -> #0 (sb_writers){.+.+.+}:
[ 5375.719018]        [<ffffffff810d97ca>] __lock_acquire+0x17ba/0x1ae0
[ 5375.719021]        [<ffffffff810da4be>] lock_acquire+0xce/0x1e0
[ 5375.719026]        [<ffffffff810d3bef>] percpu_down_read+0x4f/0xa0
[ 5375.719028]        [<ffffffff812214f7>] __sb_start_write+0xb7/0xf0
[ 5375.719031]        [<ffffffff81242eb4>] mnt_want_write+0x24/0x50
[ 5375.719035]        [<ffffffff8122ded2>] path_openat+0xd32/0x1360
[ 5375.719037]        [<ffffffff8122f86e>] do_filp_open+0x7e/0xe0
[ 5375.719040]        [<ffffffff8121d8a4>] file_open_name+0xe4/0x130
[ 5375.719043]        [<ffffffff8121d923>] filp_open+0x33/0x60
[ 5375.719073]        [<ffffffffa02776a6>] update_dev_time+0x16/0x40 [btrfs]
[ 5375.719099]        [<ffffffffa02825be>] btrfs_scratch_superblocks+0x4e/0x90 [btrfs]
[ 5375.719123]        [<ffffffffa0282665>] btrfs_destroy_dev_replace_tgtdev+0x65/0x150 [btrfs]
[ 5375.719150]        [<ffffffffa02c6c80>] btrfs_dev_replace_finishing+0x6b0/0x990 [btrfs]
[ 5375.719175]        [<ffffffffa02c729e>] btrfs_dev_replace_start+0x33e/0x540 [btrfs]
[ 5375.719199]        [<ffffffffa02c7f58>] btrfs_auto_replace_start+0xf8/0x140 [btrfs]
[ 5375.719222]        [<ffffffffa02464e6>] health_kthread+0x246/0x490 [btrfs]
[ 5375.719225]        [<ffffffff810a70df>] kthread+0xef/0x110
[ 5375.719229]        [<ffffffff81637d2f>] ret_from_fork+0x3f/0x70
[ 5375.719230]
[ 5375.719230] other info that might help us debug this:
[ 5375.719230]
[ 5375.719233] Chain exists of:
[ 5375.719233]   sb_writers --> namespace_sem --> &fs_devs->device_list_mutex
[ 5375.719233]
[ 5375.719234]  Possible unsafe locking scenario:
[ 5375.719234]
[ 5375.719234]        CPU0                    CPU1
[ 5375.719235]        ----                    ----
[ 5375.719236]   lock(&fs_devs->device_list_mutex);
[ 5375.719238]                                lock(namespace_sem);
[ 5375.719239]                                lock(&fs_devs->device_list_mutex);
[ 5375.719241]   lock(sb_writers);
[ 5375.719241]
[ 5375.719241]  *** DEADLOCK ***
[ 5375.719241]
[ 5375.719243] 4 locks held by btrfs-health/4662:
[ 5375.719266]  #0:  (&fs_info->health_mutex){+.+.+.}, at: [<ffffffffa0246303>] health_kthread+0x63/0x490 [btrfs]
[ 5375.719293]  #1:  (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.+.}, at: [<ffffffffa02c6611>] btrfs_dev_replace_finishing+0x41/0x990 [btrfs]
[ 5375.719319]  #2:  (uuid_mutex){+.+.+.}, at: [<ffffffffa0282620>] btrfs_destroy_dev_replace_tgtdev+0x20/0x150 [btrfs]
[ 5375.719343]  #3:  (&fs_devs->device_list_mutex){+.+.+.}, at: [<ffffffffa028263c>] btrfs_destroy_dev_replace_tgtdev+0x3c/0x150 [btrfs]
[ 5375.719343]
[ 5375.719343] stack backtrace:
[ 5375.719347] CPU: 2 PID: 4662 Comm: btrfs-health Not tainted 4.4.5-scst31x-debug-11+ #40
[ 5375.719348] Hardware name: Supermicro SYS-6018R-WTRT/X10DRW-iT, BIOS 1.0c 01/07/2015
[ 5375.719352]  0000000000000000 ffff880856f73880 ffffffff813529e3 ffffffff826182a0
[ 5375.719354]  ffffffff8260c090 ffff880856f738c0 ffffffff810d667c ffff880856f73930
[ 5375.719357]  ffff880861f32b40 ffff880861f32b68 0000000000000003 0000000000000004
[ 5375.719357] Call Trace:
[ 5375.719363]  [<ffffffff813529e3>] dump_stack+0x85/0xc2
[ 5375.719366]  [<ffffffff810d667c>] print_circular_bug+0x1ec/0x260
[ 5375.719369]  [<ffffffff810d97ca>] __lock_acquire+0x17ba/0x1ae0
[ 5375.719373]  [<ffffffff810f606d>] ? debug_lockdep_rcu_enabled+0x1d/0x20
[ 5375.719376]  [<ffffffff810da4be>] lock_acquire+0xce/0x1e0
[ 5375.719378]  [<ffffffff812214f7>] ? __sb_start_write+0xb7/0xf0
[ 5375.719383]  [<ffffffff810d3bef>] percpu_down_read+0x4f/0xa0
[ 5375.719385]  [<ffffffff812214f7>] ? __sb_start_write+0xb7/0xf0
[ 5375.719387]  [<ffffffff812214f7>] __sb_start_write+0xb7/0xf0
[ 5375.719389]  [<ffffffff81242eb4>] mnt_want_write+0x24/0x50
[ 5375.719393]  [<ffffffff8122ded2>] path_openat+0xd32/0x1360
[ 5375.719415]  [<ffffffffa02462a0>] ? btrfs_congested_fn+0x180/0x180 [btrfs]
[ 5375.719418]  [<ffffffff810f606d>] ? debug_lockdep_rcu_enabled+0x1d/0x20
[ 5375.719420]  [<ffffffff8122f86e>] do_filp_open+0x7e/0xe0
[ 5375.719423]  [<ffffffff810f615d>] ? rcu_read_lock_sched_held+0x6d/0x80
[ 5375.719426]  [<ffffffff81201a9b>] ? kmem_cache_alloc+0x26b/0x5d0
[ 5375.719430]  [<ffffffff8122e7d4>] ? getname_kernel+0x34/0x120
[ 5375.719433]  [<ffffffff8121d8a4>] file_open_name+0xe4/0x130
[ 5375.719436]  [<ffffffff8121d923>] filp_open+0x33/0x60
[ 5375.719462]  [<ffffffffa02776a6>] update_dev_time+0x16/0x40 [btrfs]
[ 5375.719485]  [<ffffffffa02825be>] btrfs_scratch_superblocks+0x4e/0x90 [btrfs]
[ 5375.719506]  [<ffffffffa0282665>] btrfs_destroy_dev_replace_tgtdev+0x65/0x150 [btrfs]
[ 5375.719530]  [<ffffffffa02c6c80>] btrfs_dev_replace_finishing+0x6b0/0x990 [btrfs]
[ 5375.719554]  [<ffffffffa02c6b23>] ? btrfs_dev_replace_finishing+0x553/0x990 [btrfs]
[ 5375.719576]  [<ffffffffa02c729e>] btrfs_dev_replace_start+0x33e/0x540 [btrfs]
[ 5375.719598]  [<ffffffffa02c7f58>] btrfs_auto_replace_start+0xf8/0x140 [btrfs]
[ 5375.719621]  [<ffffffffa02464e6>] health_kthread+0x246/0x490 [btrfs]
[ 5375.719641]  [<ffffffffa02463d8>] ? health_kthread+0x138/0x490 [btrfs]
[ 5375.719661]  [<ffffffffa02462a0>] ? btrfs_congested_fn+0x180/0x180 [btrfs]
[ 5375.719663]  [<ffffffff810a70df>] kthread+0xef/0x110
[ 5375.719666]  [<ffffffff810a6ff0>] ? kthread_create_on_node+0x200/0x200
[ 5375.719669]  [<ffffffff81637d2f>] ret_from_fork+0x3f/0x70
[ 5375.719672]  [<ffffffff810a6ff0>] ? kthread_create_on_node+0x200/0x200
[ 5375.719697] ------------[ cut here ]------------

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reported-by: Yauhen Kharuzhy <yauhen.kharuzhy@zavadatar.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
Dan Carpenter
f5ecec3ce2 btrfs: send: silence an integer overflow warning
The "sizeof(*arg->clone_sources) * arg->clone_sources_count" expression
can overflow.  It causes several static checker warnings.  It's all
under CAP_SYS_ADMIN so it's not that serious but lets silence the
warnings.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
Luis de Bethencourt
41b34accb2 btrfs: avoid overflowing f_bfree
Since mixed block groups accounting isn't byte-accurate and f_bree is an
unsigned integer, it could overflow. Avoid this.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Suggested-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
Luis de Bethencourt
ae02d1bd07 btrfs: fix mixed block count of available space
Metadata for mixed block is already accounted in total data and should not
be counted as part of the free metadata space.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=114281
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
Austin S. Hemmelgarn
88be159c90 btrfs: allow balancing to dup with multi-device
Currently, we don't allow the user to try and rebalance to a dup profile
on a multi-device filesystem.  In most cases, this is a perfectly sensible
restriction as raid1 uses the same amount of space and provides better
protection.

However, when reshaping a multi-device filesystem down to a single device
filesystem, this requires the user to convert metadata and system chunks
to single profile before deleting devices, and then convert again to dup,
which leaves a period of time where metadata integrity is reduced.

This patch removes the single-device-only restriction from converting to
dup profile to remove this potential data integrity reduction.

Signed-off-by: Austin S. Hemmelgarn <ahferroin7@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 15:22:49 +02:00
David Sterba
2355ac8495 btrfs: ioctl: reorder exclusive op check in RM_DEV
Move the op exclusivity check before the other code (same as in
ADD_DEV).

Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 14:58:00 +02:00
David Sterba
58409edd2d btrfs: kill unused writepage_io_hook callback
It seems to be long time unused, since 2008 and
6885f308b5570 ("Btrfs: Misc 2.6.25 updates").

Propagating the removal touches some code but has no functional effect.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-06 14:57:57 +02:00
Mathias Krause
8148a73c99 proc: prevent accessing /proc/<PID>/environ until it's ready
If /proc/<PID>/environ gets read before the envp[] array is fully set up
in create_{aout,elf,elf_fdpic,flat}_tables(), we might end up trying to
read more bytes than are actually written, as env_start will already be
set but env_end will still be zero, making the range calculation
underflow, allowing to read beyond the end of what has been written.

Fix this as it is done for /proc/<PID>/cmdline by testing env_end for
zero.  It is, apparently, intentionally set last in create_*_tables().

This bug was found by the PaX size_overflow plugin that detected the
arithmetic underflow of 'this_len = env_end - (env_start + src)' when
env_end is still zero.

The expected consequence is that userland trying to access
/proc/<PID>/environ of a not yet fully set up process may get
inconsistent data as we're in the middle of copying in the environment
variables.

Fixes: https://forums.grsecurity.net/viewtopic.php?f=3&t=4363
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=116461
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: Pax Team <pageexec@freemail.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
James Morris
0250abcd72 Merge tag 'keys-next-20160505' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs into next 2016-05-06 09:29:00 +10:00
Linus Torvalds
c5e0666c5a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull userns fix from Eric Biederman:
 "This contains just a single fix for a nasty oops"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  propogate_mnt: Handle the first propogated copy being a slave
2016-05-05 08:41:57 -07:00
Eric W. Biederman
5ec0811d30 propogate_mnt: Handle the first propogated copy being a slave
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.

Cc: stable@vger.kernel.org
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>
2016-05-05 09:54:45 -05:00
Al Viro
6a480a7842 ecryptfs: fix handling of directory opening
First of all, trying to open them r/w is idiocy; it's guaranteed to fail.
Moreover, assigning ->f_pos and assuming that everything will work is
blatantly broken - try that with e.g. tmpfs as underlying layer and watch
the fireworks.  There may be a non-trivial amount of state associated with
current IO position, well beyond the numeric offset.  Using the single
struct file associated with underlying inode is really not a good idea;
we ought to open one for each ecryptfs directory struct file.

Additionally, file_operations both for directories and non-directories are
full of pointless methods; non-directories should *not* have ->iterate(),
directories should not have ->flush(), ->fasync() and ->splice_read().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-04 14:04:13 -04:00
Anand Jain
88acff64c6 btrfs: cleanup assigning next active device with a check
Creates helper fucntion as needed by the device delete
and replace operations. Also now it checks if the next
device being assigned is an active device.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-04 10:41:08 +02:00
Anand Jain
8ed01abe7d btrfs: s_bdev is not null after missing replace
Yauhen reported in the ML that s_bdev is null at mount, and
s_bdev gets updated to some device when missing device is
replaced, as because bdev is null for missing device, things
gets matched up. Fix this by checking if s_bdev is set. I
didn't want to completely remove updating s_bdev because
the future multi device support at vfs layer may need it.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reported-by: Yauhen Kharuzhy <yauhen.kharuzhy@zavadatar.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-05-04 09:52:44 +02:00
David S. Miller
cba6532100 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/ipv4/ip_gre.c

Minor conflicts between tunnel bug fixes in net and
ipv6 tunnel cleanups in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-04 00:52:29 -04:00
Linus Torvalds
610603a520 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fixes from Miklos Szeredi:
 "Fix a regression and update the MAINTAINERS entry for fuse"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: update mailing list in MAINTAINERS
  fuse: Fix return value from fuse_get_user_pages()
2016-05-03 14:23:58 -07:00
Chao Yu
3f8ab27085 f2fs: factor out fsync inode entry operations
Factor out fsync inode entry operations into {add,del}_fsync_inode.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-03 11:20:07 -07:00
Chao Yu
c81ced05b2 f2fs: fix to clear page private flag
Commit 28bc106b2346 ("f2fs: support revoking atomic written pages")
forgot to clear page private flag correctly, fix it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-03 11:20:06 -07:00
Chao Yu
23dc974eed f2fs: fix to clear private data in page
Private data in page should be removed during ->releasepage or
->invalidatepage, otherwise garbage data would be remained in that page.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-03 11:20:05 -07:00
Al Viro
9ac3d3e846 nfs: switch to ->iterate_shared()
aside of the usual care about seeding dcache from readdir, we need
to be careful about the pagecache evictions here.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:53 -04:00
Al Viro
9cf843e3f4 lookup_open(): lock the parent shared unless O_CREAT is given
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:17 -04:00
Al Viro
6fbd07146d lookup_open(): put the dentry fed to ->lookup() or ->atomic_open() into in-lookup hash
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:16 -04:00
Al Viro
12fa5e2404 lookup_open(): expand the call of real_lookup()
... and lose the duplicate IS_DEADDIR() - we'd already checked that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:16 -04:00
Al Viro
384f26e28f atomic_open(): reorder and clean up a bit
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:15 -04:00
Al Viro
1643b43fbd lookup_open(): lift the "fallback to !O_CREAT" logics from atomic_open()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:15 -04:00
Al Viro
b3d58eaffb atomic_open(): be paranoid about may_open() return value
It should never return positives; however, with Linux S&M crowd
involved, no bogosity is impossible.  Results would be unpleasant...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:14 -04:00
Al Viro
0fb1ea0933 atomic_open(): delay open_to_namei_flags() until the method call
nobody else needs that transformation.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:14 -04:00
Al Viro
fe9ec8291f do_last(): take fput() on error after opening to out:
make it conditional on *opened & FILE_OPENED; in addition to getting
rid of exit_fput: thing, it simplifies atomic_open() cleanup on
may_open() failure.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:13 -04:00
Al Viro
47f9dbd387 do_last(): get rid of duplicate ELOOP check
may_open() will catch it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:13 -04:00
Al Viro
55db2fd936 atomic_open(): massage the create_error logics a bit
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:12 -04:00
Al Viro
9d0728e16e atomic_open(): consolidate "overridden ENOENT" in open-yourself cases
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:12 -04:00
Al Viro
5249e411b4 atomic_open(): don't bother with EEXIST check - it's done in do_last()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:51:11 -04:00
Al Viro
df889b3631 Merge branch 'for-linus' into work.lookups 2016-05-02 19:49:46 -04:00
Al Viro
ce8644fcad lookup_open(): expand the call of vfs_create()
Lift IS_DEADDIR handling up into the part common with atomic_open(),
remove it from the latter.  Collapse permission checks into the
call of may_o_create(), getting it closer to atomic_open() case.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:49:33 -04:00
Al Viro
6ac087099e path_openat(): take O_PATH handling out of do_last()
do_last() and lookup_open() simpler that way and so does O_PATH
itself.  As it bloody well should: we find what the pathname
resolves to, same way as in stat() et.al. and associate it with
FMODE_PATH struct file.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:49:33 -04:00
Al Viro
3b0a3c1ac1 simple local filesystems: switch to ->iterate_shared()
no changes needed (XFS isn't simple, but it has the same parallelism
in the interesting parts exercised from CXFS).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-02 19:49:32 -04:00