linux-toradex.git/fs, branch v4.9.16

ext4: don't BUG when truncating encrypted inodes on the orphan list

2017-03-18T11:14:34+00:00

commit 0d06863f903ac5f4f6efb0273079d27de3e53a28 upstream.

Fix a BUG when the kernel tries to mount a file system constructed as
follows:

echo foo > foo.txt
mke2fs -Fq -t ext4 -O encrypt foo.img 100
debugfs -w foo.img << EOF
write foo.txt a
set_inode_field a i_flags 0x80800
set_super_value s_last_orphan 12
quit
EOF

root@kvm-xfstests:~# mount -o loop foo.img /mnt
[  160.238770] ------------[ cut here ]------------
[  160.240106] kernel BUG at /usr/projects/linux/ext4/fs/ext4/inode.c:3874!
[  160.240106] invalid opcode: 0000 [#1] SMP
[  160.240106] Modules linked in:
[  160.240106] CPU: 0 PID: 2547 Comm: mount Tainted: G        W       4.10.0-rc3-00034-gcdd33b941b67 #227
[  160.240106] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1 04/01/2014
[  160.240106] task: f4518000 task.stack: f47b6000
[  160.240106] EIP: ext4_block_zero_page_range+0x1a7/0x2b4
[  160.240106] EFLAGS: 00010246 CPU: 0
[  160.240106] EAX: 00000001 EBX: f7be4b50 ECX: f47b7dc0 EDX: 00000007
[  160.240106] ESI: f43b05a8 EDI: f43babec EBP: f47b7dd0 ESP: f47b7dac
[  160.240106]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
[  160.240106] CR0: 80050033 CR2: bfd85b08 CR3: 34a00680 CR4: 000006f0
[  160.240106] Call Trace:
[  160.240106]  ext4_truncate+0x1e9/0x3e5
[  160.240106]  ext4_fill_super+0x286f/0x2b1e
[  160.240106]  ? set_blocksize+0x2e/0x7e
[  160.240106]  mount_bdev+0x114/0x15f
[  160.240106]  ext4_mount+0x15/0x17
[  160.240106]  ? ext4_calculate_overhead+0x39d/0x39d
[  160.240106]  mount_fs+0x58/0x115
[  160.240106]  vfs_kern_mount+0x4b/0xae
[  160.240106]  do_mount+0x671/0x8c3
[  160.240106]  ? _copy_from_user+0x70/0x83
[  160.240106]  ? strndup_user+0x31/0x46
[  160.240106]  SyS_mount+0x57/0x7b
[  160.240106]  do_int80_syscall_32+0x4f/0x61
[  160.240106]  entry_INT80_32+0x2f/0x2f
[  160.240106] EIP: 0xb76b919e
[  160.240106] EFLAGS: 00000246 CPU: 0
[  160.240106] EAX: ffffffda EBX: 08053838 ECX: 08052188 EDX: 080537e8
[  160.240106] ESI: c0ed0000 EDI: 00000000 EBP: 080537e8 ESP: bfa13660
[  160.240106]  DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b
[  160.240106] Code: 59 8b 00 a8 01 0f 84 09 01 00 00 8b 07 66 25 00 f0 66 3d 00 80 75 61 89 f8 e8 3e e2 ff ff 84 c0 74 56 83 bf 48 02 00 00 00 75 02 <0f> 0b 81 7d e8 00 10 00 00 74 02 0f 0b 8b 43 04 8b 53 08 31 c9
[  160.240106] EIP: ext4_block_zero_page_range+0x1a7/0x2b4 SS:ESP: 0068:f47b7dac
[  160.317241] ---[ end trace d6a773a375c810a5 ]---

The problem is that when the kernel tries to truncate an inode in
ext4_truncate(), it tries to clear any on-disk data beyond i_size.
Without the encryption key, it can't do that, and so it triggers a
BUG.

E2fsck does *not* provide this service, and in practice most file
systems have their orphan list processed by e2fsck, so to avoid
crashing, this patch skips this step if we don't have access to the
encryption key (which is the case when processing the orphan list; in
all other cases, we will have the encryption key, or the kernel
wouldn't have allowed the file to be opened).

An open question is whether the fact that e2fsck isn't clearing the
bytes beyond i_size causing problems --- and if we've lived with it
not doing it for so long, can we drop this from the kernel replay of
the orphan list in all cases (not just when we don't have the key for
encrypted inodes).

Addresses-Google-Bug: #35209576

Signed-off-by: Theodore Ts'o 
Signed-off-by: Eric Biggers 
Signed-off-by: Greg Kroah-Hartman

fat: fix using uninitialized fields of fat_inode/fsinfo_inode

2017-03-15T02:02:52+00:00

commit c0d0e351285161a515396b7b1ee53ec9ffd97e3c upstream.

Recently fallocate patch was merged and it uses
MSDOS_I(inode)->mmu_private at fat_evict_inode().  However,
fat_inode/fsinfo_inode that was introduced in past didn't initialize
MSDOS_I(inode) properly.

With those combinations, it became the cause of accessing random entry
in FAT area.

Link: http://lkml.kernel.org/r/87pohrj4i8.fsf@mail.parknet.co.jp
Signed-off-by: OGAWA Hirofumi 
Reported-by: Moreno Bartalucci 
Tested-by: Moreno Bartalucci 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ceph: remove req from unsafe list when unregistering it

2017-03-15T02:02:45+00:00

commit df963ea8a082d31521a120e8e31a29ad8a1dc215 upstream.

There's no reason a request should ever be on a s_unsafe list but not
in the request tree.

Link: http://tracker.ceph.com/issues/18474
Signed-off-by: Jeff Layton 
Reviewed-by: Yan, Zheng 
Signed-off-by: Ilya Dryomov 
Signed-off-by: Greg Kroah-Hartman

orangefs: Use RCU for destroy_inode

2017-03-15T02:02:44+00:00

commit 0695d7dc1d9f19b82ec2cae24856bddce278cfe6 upstream.

freeing of inodes must be RCU-delayed on all filesystems

Signed-off-by: Peter Zijlstra (Intel) 
Signed-off-by: Al Viro 
Signed-off-by: Greg Kroah-Hartman

fs: Better permission checking for submounts

2017-03-15T02:02:44+00:00

commit 93faccbbfa958a9668d3ab4e30f38dd205cee8d8 upstream.

To support unprivileged users mounting filesystems two permission
checks have to be performed: a test to see if the user allowed to
create a mount in the mount namespace, and a test to see if
the user is allowed to access the specified filesystem.

The automount case is special in that mounting the original filesystem
grants permission to mount the sub-filesystems, to any user who
happens to stumble across the their mountpoint and satisfies the
ordinary filesystem permission checks.

Attempting to handle the automount case by using override_creds
almost works.  It preserves the idea that permission to mount
the original filesystem is permission to mount the sub-filesystem.
Unfortunately using override_creds messes up the filesystems
ordinary permission checks.

Solve this by being explicit that a mount is a submount by introducing
vfs_submount, and using it where appropriate.

vfs_submount uses a new mount internal mount flags MS_SUBMOUNT, to let
sget and friends know that a mount is a submount so they can take appropriate
action.

sget and sget_userns are modified to not perform any permission checks
on submounts.

follow_automount is modified to stop using override_creds as that
has proven problemantic.

do_mount is modified to always remove the new MS_SUBMOUNT flag so
that we know userspace will never by able to specify it.

autofs4 is modified to stop using current_real_cred that was put in
there to handle the previous version of submount permission checking.

cifs is modified to pass the mountpoint all of the way down to vfs_submount.

debugfs is modified to pass the mountpoint all of the way down to
trace_automount by adding a new parameter.  To make this change easier
a new typedef debugfs_automount_t is introduced to capture the type of
the debugfs automount function.

Fixes: 069d5ac9ae0d ("autofs:  Fix automounts by using current_real_cred()->uid")
Fixes: aeaa4a79ff6a ("fs: Call d_automount with the filesystems creds")
Reviewed-by: Trond Myklebust 
Reviewed-by: Seth Forshee 
Signed-off-by: "Eric W. Biederman" 
Signed-off-by: Greg Kroah-Hartman

mnt: Tuck mounts under others instead of creating shadow/side mounts.

2017-03-15T02:02:43+00:00

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 
Signed-off-by: "Eric W. Biederman" 
Signed-off-by: Greg Kroah-Hartman

ceph: update readpages osd request according to size of pages

2017-03-12T05:41:53+00:00

commit d641df819db8b80198fd85d9de91137e8a823b07 upstream.

add_to_page_cache_lru() can fails, so the actual pages to read
can be smaller than the initial size of osd request. We need to
update osd request size in that case.

Signed-off-by: Yan, Zheng 
Reviewed-by: Jeff Layton 
Signed-off-by: Greg Kroah-Hartman

f2fs: avoid to issue redundant discard commands

2017-03-12T05:41:51+00:00

commit 8b107f5b97772c7c0c218302e9a4d15b4edf50b4 upstream.

If segs_per_sec is over 1 like under SMR, previously f2fs issues discard
commands redundantly on the same section, since we didn't move end position
for the previous discard command.

E.g.,

                       start  end
                         |    |
      prefree_bitmap = [01111100111100]

And, after issue discard for this section,
                             end      start
                              |        |
      prefree_bitmap = [01111100111100]

Select this section again by searching from (end + 1),
                             start  end
                                |   |
      prefree_bitmap = [01111100111100]

Fixes: 36abef4e796d38 ("f2fs: introduce mode=lfs mount option")
Cc: Damien Le Moal 
Signed-off-by: Jaegeuk Kim 
Signed-off-by: Greg Kroah-Hartman

f2fs: add ovp valid_blocks check for bg gc victim to fg_gc

2017-03-12T05:41:51+00:00

commit e93b9865251a0503d83fd570e7d5a7c8bc351715 upstream.

For foreground gc, greedy algorithm should be adapted, which makes
this formula work well:

	(2 * (100 / config.overprovision + 1) + 6)

But currently, we fg_gc have a prior to select bg_gc victim segments to gc
first, these victims are selected by cost-benefit algorithm, we can't guarantee
such segments have the small valid blocks, which may destroy the f2fs rule, on
the worstest case, would consume all the free segments.

This patch fix this by add a filter in check_bg_victims, if segment's has # of
valid blocks over overprovision ratio, skip such segments.

Signed-off-by: Hou Pengyang 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim 
Signed-off-by: Greg Kroah-Hartman

f2fs: fix multiple f2fs_add_link() calls having same name

2017-03-12T05:41:51+00:00

commit 88c5c13a5027b36d914536fdba23f069d7067204 upstream.

It turns out a stakable filesystem like sdcardfs in AOSP can trigger multiple
vfs_create() to lower filesystem. In that case, f2fs will add multiple dentries
having same name which breaks filesystem consistency.

Until upper layer fixes, let's work around by f2fs, which shows actually not
much performance regression.

Signed-off-by: Jaegeuk Kim 
Signed-off-by: Greg Kroah-Hartman