48224 Commits

Author SHA1 Message Date
Wu Bo
1de356b13c ceph: fix double unlock in handle_cap_export()
[ Upstream commit 4d8e28ff3106b093d98bfd2eceb9b430c70a8758 ]

If the ceph_mdsc_open_export_target_session() return fails, it will
do a "goto retry", but the session mutex has already been unlocked.
Re-lock the mutex in that case to ensure that we don't unlock it
twice.

Signed-off-by: Wu Bo <wubo40@huawei.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 16:41:48 +02:00
Xiyu Yang
1957df4975 configfs: fix config_item refcnt leak in configfs_rmdir()
[ Upstream commit 8aebfffacfa379ba400da573a5bf9e49634e38cb ]

configfs_rmdir() invokes configfs_get_config_item(), which returns a
reference of the specified config_item object to "parent_item" with
increased refcnt.

When configfs_rmdir() returns, local variable "parent_item" becomes
invalid, so the refcount should be decreased to keep refcount balanced.

The reference counting issue happens in one exception handling path of
configfs_rmdir(). When down_write_killable() fails, the function forgets
to decrease the refcnt increased by configfs_get_config_item(), causing
a refcnt leak.

Fix this issue by calling config_item_put() when down_write_killable()
fails.

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 16:41:45 +02:00
Al Viro
26204c47c8 fix multiplication overflow in copy_fdtable()
[ Upstream commit 4e89b7210403fa4a8acafe7c602b6212b7af6c3b ]

cpy and set really should be size_t; we won't get an overflow on that,
since sysctl_nr_open can't be set above ~(size_t)0 / sizeof(void *),
so nr that would've managed to overflow size_t on that multiplication
won't get anywhere near copy_fdtable() - we'll fail with EMFILE
before that.

Cc: stable@kernel.org # v2.6.25+
Fixes: 9cfe015aa424 (get rid of NR_OPEN and introduce a sysctl_nr_open)
Reported-by: Thiago Macieira <thiago.macieira@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 16:41:40 +02:00
Eric W. Biederman
72d5fb7f67 exec: Move would_dump into flush_old_exec
commit f87d1c9559164294040e58f5e3b74a162bf7c6e8 upstream.

I goofed when I added mm->user_ns support to would_dump.  I missed the
fact that in the case of binfmt_loader, binfmt_em86, binfmt_misc, and
binfmt_script bprm->file is reassigned.  Which made the move of
would_dump from setup_new_exec to __do_execve_file before exec_binprm
incorrect as it can result in would_dump running on the script instead
of the interpreter of the script.

The net result is that the code stopped making unreadable interpreters
undumpable.  Which allows them to be ptraced and written to disk
without special permissions.  Oops.

The move was necessary because the call in set_new_exec was after
bprm->mm was no longer valid.

To correct this mistake move the misplaced would_dump from
__do_execve_file into flos_old_exec, before exec_mmap is called.

I tested and confirmed that without this fix I can attach with gdb to
a script with an unreadable interpreter, and with this fix I can not.

Cc: stable@vger.kernel.org
Fixes: f84df2a6f268 ("exec: Ensure mm->user_ns contains the execed files")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:15:41 +02:00
Ronnie Sahlberg
f0fff9a77e cifs: Fix a race condition with cifs_echo_request
[ Upstream commit f2caf901c1b7ce65f9e6aef4217e3241039db768 ]

There is a race condition with how we send (or supress and don't send)
smb echos that will cause the client to incorrectly think the
server is unresponsive and thus needs to be reconnected.

Summary of the race condition:
 1) Daisy chaining scheduling creates a gap.
 2) If traffic comes unfortunate shortly after
    the last echo, the planned echo is suppressed.
 3) Due to the gap, the next echo transmission is delayed
    until after the timeout, which is set hard to twice
    the echo interval.

This is fixed by changing the timeouts from 2 to three times the echo interval.

Detailed description of the bug: https://lutz.donnerhacke.de/eng/Blog/Groundhog-Day-with-SMB-remount

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:34 +02:00
Samuel Cabrero
79d25ee27b cifs: Check for timeout on Negotiate stage
[ Upstream commit 76e752701a8af4404bbd9c45723f7cbd6e4a251e ]

Some servers seem to accept connections while booting but never send
the SMBNegotiate response neither close the connection, causing all
processes accessing the share hang on uninterruptible sleep state.

This happens when the cifs_demultiplex_thread detects the server is
unresponsive so releases the socket and start trying to reconnect.
At some point, the faulty server will accept the socket and the TCP
status will be set to NeedNegotiate. The first issued command accessing
the share will start the negotiation (pid 5828 below), but the response
will never arrive so other commands will be blocked waiting on the mutex
(pid 55352).

This patch checks for unresponsive servers also on the negotiate stage
releasing the socket and reconnecting if the response is not received
and checking again the tcp state when the mutex is acquired.

PID: 55352  TASK: ffff880fd6cc02c0  CPU: 0   COMMAND: "ls"
 #0 [ffff880fd9add9f0] schedule at ffffffff81467eb9
 #1 [ffff880fd9addb38] __mutex_lock_slowpath at ffffffff81468fe0
 #2 [ffff880fd9addba8] mutex_lock at ffffffff81468b1a
 #3 [ffff880fd9addbc0] cifs_reconnect_tcon at ffffffffa042f905 [cifs]
 #4 [ffff880fd9addc60] smb_init at ffffffffa042faeb [cifs]
 #5 [ffff880fd9addca0] CIFSSMBQPathInfo at ffffffffa04360b5 [cifs]
 ....

Which is waiting a mutex owned by:

PID: 5828   TASK: ffff880fcc55e400  CPU: 0   COMMAND: "xxxx"
 #0 [ffff880fbfdc19b8] schedule at ffffffff81467eb9
 #1 [ffff880fbfdc1b00] wait_for_response at ffffffffa044f96d [cifs]
 #2 [ffff880fbfdc1b60] SendReceive at ffffffffa04505ce [cifs]
 #3 [ffff880fbfdc1bb0] CIFSSMBNegotiate at ffffffffa0438d79 [cifs]
 #4 [ffff880fbfdc1c50] cifs_negotiate_protocol at ffffffffa043b383 [cifs]
 #5 [ffff880fbfdc1c80] cifs_reconnect_tcon at ffffffffa042f911 [cifs]
 #6 [ffff880fbfdc1d20] smb_init at ffffffffa042faeb [cifs]
 #7 [ffff880fbfdc1d60] CIFSSMBQFSInfo at ffffffffa0434eb0 [cifs]
 ....

Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurélien Aptel <aaptel@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:34 +02:00
Logan Gunthorpe
da97a80a65 chardev: add helper function to register char devs with a struct device
commit 233ed09d7fdacf592ee91e6c97ce5f4364fbe7c0 upstream.

Credit for this patch goes is shared with Dan Williams [1]. I've
taken things one step further to make the helper function more
useful and clean up calling code.

There's a common pattern in the kernel whereby a struct cdev is placed
in a structure along side a struct device which manages the life-cycle
of both. In the naive approach, the reference counting is broken and
the struct device can free everything before the chardev code
is entirely released.

Many developers have solved this problem by linking the internal kobjs
in this fashion:

cdev.kobj.parent = &parent_dev.kobj;

The cdev code explicitly gets and puts a reference to it's kobj parent.
So this seems like it was intended to be used this way. Dmitrty Torokhov
first put this in place in 2012 with this commit:

2f0157f char_dev: pin parent kobject

and the first instance of the fix was then done in the input subsystem
in the following commit:

4a215aa Input: fix use-after-free introduced with dynamic minor changes

Subsequently over the years, however, this issue seems to have tripped
up multiple developers independently. For example, see these commits:

0d5b7da iio: Prevent race between IIO chardev opening and IIO device
(by Lars-Peter Clausen in 2013)

ba0ef85 tpm: Fix initialization of the cdev
(by Jason Gunthorpe in 2015)

5b28dde [media] media: fix use-after-free in cdev_put() when app exits
after driver unbind
(by Shauh Khan in 2016)

This technique is similarly done in at least 15 places within the kernel
and probably should have been done so in another, at least, 5 places.
The kobj line also looks very suspect in that one would not expect
drivers to have to mess with kobject internals in this way.
Even highly experienced kernel developers can be surprised by this
code, as seen in [2].

To help alleviate this situation, and hopefully prevent future
wasted effort on this problem, this patch introduces a helper function
to register a char device along with its parent struct device.
This creates a more regular API for tying a char device to its parent
without the developer having to set members in the underlying kobject.

This patch introduce cdev_device_add and cdev_device_del which
replaces a common pattern including setting the kobj parent, calling
cdev_add and then calling device_add. It also introduces cdev_set_parent
for the few cases that set the kobject parent without using device_add.

[1] https://lkml.org/lkml/2017/2/13/700
[2] https://lkml.org/lkml/2017/2/10/370

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:32 +02:00
Shijie Luo
e94c149b8a ext4: add cond_resched() to ext4_protect_reserved_inode
commit af133ade9a40794a37104ecbcc2827c0ea373a3c upstream.

When journal size is set too big by "mkfs.ext4 -J size=", or when
we mount a crafted image to make journal inode->i_size too big,
the loop, "while (i < num)", holds cpu too long. This could cause
soft lockup.

[  529.357541] Call trace:
[  529.357551]  dump_backtrace+0x0/0x198
[  529.357555]  show_stack+0x24/0x30
[  529.357562]  dump_stack+0xa4/0xcc
[  529.357568]  watchdog_timer_fn+0x300/0x3e8
[  529.357574]  __hrtimer_run_queues+0x114/0x358
[  529.357576]  hrtimer_interrupt+0x104/0x2d8
[  529.357580]  arch_timer_handler_virt+0x38/0x58
[  529.357584]  handle_percpu_devid_irq+0x90/0x248
[  529.357588]  generic_handle_irq+0x34/0x50
[  529.357590]  __handle_domain_irq+0x68/0xc0
[  529.357593]  gic_handle_irq+0x6c/0x150
[  529.357595]  el1_irq+0xb8/0x140
[  529.357599]  __ll_sc_atomic_add_return_acquire+0x14/0x20
[  529.357668]  ext4_map_blocks+0x64/0x5c0 [ext4]
[  529.357693]  ext4_setup_system_zone+0x330/0x458 [ext4]
[  529.357717]  ext4_fill_super+0x2170/0x2ba8 [ext4]
[  529.357722]  mount_bdev+0x1a8/0x1e8
[  529.357746]  ext4_mount+0x44/0x58 [ext4]
[  529.357748]  mount_fs+0x50/0x170
[  529.357752]  vfs_kern_mount.part.9+0x54/0x188
[  529.357755]  do_mount+0x5ac/0xd78
[  529.357758]  ksys_mount+0x9c/0x118
[  529.357760]  __arm64_sys_mount+0x28/0x38
[  529.357764]  el0_svc_common+0x78/0x130
[  529.357766]  el0_svc_handler+0x38/0x78
[  529.357769]  el0_svc+0x8/0xc
[  541.356516] watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [mount:18674]

Link: https://lore.kernel.org/r/20200211011752.29242-1-luoshijie1@huawei.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Shijie Luo <luoshijie1@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:29 +02:00
Kees Cook
c7adf03146 binfmt_elf: Do not move brk for INTERP-less ET_EXEC
commit 7be3cb019db1cbd5fd5ffe6d64a23fefa4b6f229 upstream.

When brk was moved for binaries without an interpreter, it should have
been limited to ET_DYN only. In other words, the special case was an
ET_DYN that lacks an INTERP, not just an executable that lacks INTERP.
The bug manifested for giant static executables, where the brk would end
up in the middle of the text area on 32-bit architectures.

Reported-and-tested-by: Richard Kojedzinszky <richard@kojedz.in>
Fixes: bbdc6076d2e5 ("binfmt_elf: move brk out of mmap when doing direct loader exec")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:15:29 +02:00
Kees Cook
4e3f9b3f7c binfmt_elf: move brk out of mmap when doing direct loader exec
commit bbdc6076d2e5d07db44e74c11b01a3e27ab90b32 upstream.

Commmit eab09532d400 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE"),
made changes in the rare case when the ELF loader was directly invoked
(e.g to set a non-inheritable LD_LIBRARY_PATH, testing new versions of
the loader), by moving into the mmap region to avoid both ET_EXEC and
PIE binaries.  This had the effect of also moving the brk region into
mmap, which could lead to the stack and brk being arbitrarily close to
each other.  An unlucky process wouldn't get its requested stack size
and stack allocations could end up scribbling on the heap.

This is illustrated here.  In the case of using the loader directly, brk
(so helpfully identified as "[heap]") is allocated with the _loader_ not
the binary.  For example, with ASLR entirely disabled, you can see this
more clearly:

$ /bin/cat /proc/self/maps
555555554000-55555555c000 r-xp 00000000 ... /bin/cat
55555575b000-55555575c000 r--p 00007000 ... /bin/cat
55555575c000-55555575d000 rw-p 00008000 ... /bin/cat
55555575d000-55555577e000 rw-p 00000000 ... [heap]
...
7ffff7ff7000-7ffff7ffa000 r--p 00000000 ... [vvar]
7ffff7ffa000-7ffff7ffc000 r-xp 00000000 ... [vdso]
7ffff7ffc000-7ffff7ffd000 r--p 00027000 ... /lib/x86_64-linux-gnu/ld-2.27.so
7ffff7ffd000-7ffff7ffe000 rw-p 00028000 ... /lib/x86_64-linux-gnu/ld-2.27.so
7ffff7ffe000-7ffff7fff000 rw-p 00000000 ...
7ffffffde000-7ffffffff000 rw-p 00000000 ... [stack]

$ /lib/x86_64-linux-gnu/ld-2.27.so /bin/cat /proc/self/maps
...
7ffff7bcc000-7ffff7bd4000 r-xp 00000000 ... /bin/cat
7ffff7bd4000-7ffff7dd3000 ---p 00008000 ... /bin/cat
7ffff7dd3000-7ffff7dd4000 r--p 00007000 ... /bin/cat
7ffff7dd4000-7ffff7dd5000 rw-p 00008000 ... /bin/cat
7ffff7dd5000-7ffff7dfc000 r-xp 00000000 ... /lib/x86_64-linux-gnu/ld-2.27.so
7ffff7fb2000-7ffff7fd6000 rw-p 00000000 ...
7ffff7ff7000-7ffff7ffa000 r--p 00000000 ... [vvar]
7ffff7ffa000-7ffff7ffc000 r-xp 00000000 ... [vdso]
7ffff7ffc000-7ffff7ffd000 r--p 00027000 ... /lib/x86_64-linux-gnu/ld-2.27.so
7ffff7ffd000-7ffff7ffe000 rw-p 00028000 ... /lib/x86_64-linux-gnu/ld-2.27.so
7ffff7ffe000-7ffff8020000 rw-p 00000000 ... [heap]
7ffffffde000-7ffffffff000 rw-p 00000000 ... [stack]

The solution is to move brk out of mmap and into ELF_ET_DYN_BASE since
nothing is there in the direct loader case (and ET_EXEC is still far
away at 0x400000).  Anything that ran before should still work (i.e.
the ultimately-launched binary already had the brk very far from its
text, so this should be no different from a COMPAT_BRK standpoint).  The
only risk I see here is that if someone started to suddenly depend on
the entire memory space lower than the mmap region being available when
launching binaries via a direct loader execs which seems highly
unlikely, I'd hope: this would mean a binary would _not_ work when
exec()ed normally.

(Note that this is only done under CONFIG_ARCH_HAS_ELF_RANDOMIZATION
when randomization is turned on.)

Link: http://lkml.kernel.org/r/20190422225727.GA21011@beast
Link: https://lkml.kernel.org/r/CAGXu5jJ5sj3emOT2QPxQkNQk0qbU6zEfu9=Omfhx_p0nCKPSjA@mail.gmail.com
Fixes: eab09532d400 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Ali Saidi <alisaidi@amazon.com>
Cc: Ali Saidi <alisaidi@amazon.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:15:27 +02:00
Ronnie Sahlberg
3f9b0d0f19 cifs: protect updating server->dstaddr with a spinlock
[ Upstream commit fada37f6f62995cc449b36ebba1220594bfe55fe ]

We use a spinlock while we are reading and accessing the destination address for a server.
We need to also use this spinlock to protect when we are modifying this address from
reconn_set_ipaddr().

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-10 10:28:01 +02:00
Andreas Gruenbacher
f92f290414 nfs: Fix potential posix_acl refcnt leak in nfs3_set_acl
commit 7648f939cb919b9d15c21fff8cd9eba908d595dc upstream.

nfs3_set_acl keeps track of the acl it allocated locally to determine if an acl
needs to be released at the end.  This results in a memory leak when the
function allocates an acl as well as a default acl.  Fix by releasing acls
that differ from the acl originally passed into nfs3_set_acl.

Fixes: b7fa0554cf1b ("[PATCH] NFS: Add support for NFSv3 ACLs")
Reported-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-05 19:14:40 +02:00
Xiyu Yang
a05346de2c btrfs: fix block group leak when removing fails
commit f6033c5e333238f299c3ae03fac8cc1365b23b77 upstream.

btrfs_remove_block_group() invokes btrfs_lookup_block_group(), which
returns a local reference of the block group that contains the given
bytenr to "block_group" with increased refcount.

When btrfs_remove_block_group() returns, "block_group" becomes invalid,
so the refcount should be decreased to keep refcount balanced.

The reference counting issue happens in several exception handling paths
of btrfs_remove_block_group(). When those error scenarios occur such as
btrfs_alloc_path() returns NULL, the function forgets to decrease its
refcnt increased by btrfs_lookup_block_group() and will cause a refcnt
leak.

Fix this issue by jumping to "out_put_group" label and calling
btrfs_put_block_group() when those error scenarios occur.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-05 19:14:31 +02:00
Theodore Ts'o
fb57d4e291 ext4: fix special inode number checks in __ext4_iget()
commit 191ce17876c9367819c4b0a25b503c0f6d9054d8 upstream.

The check for special (reserved) inode number checks in __ext4_iget()
was broken by commit 8a363970d1dc: ("ext4: avoid declaring fs
inconsistent due to invalid file handles").  This was caused by a
botched reversal of the sense of the flag now known as
EXT4_IGET_SPECIAL (when it was previously named EXT4_IGET_NORMAL).
Fix the logic appropriately.

Fixes: 8a363970d1dc ("ext4: avoid declaring fs inconsistent...")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-05 19:14:29 +02:00
Al Viro
fcd41818e1 propagate_one(): mnt_set_mountpoint() needs mount_lock
commit b0d3869ce9eeacbb1bbd541909beeef4126426d5 upstream.

... to protect the modification of mp->m_count done by it.  Most of
the places that modify that thing also have namespace_lock held,
but not all of them can do so, so we really need mount_lock here.
Kudos to Piotr Krysiuk <piotras@gmail.com>, who'd spotted a related
bug in pivot_root(2) (fixed unnoticed in 5.3); search for other
similar turds has caught out this one.

Cc: stable@kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Piotr Krysiuk <piotras@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:20 +02:00
Ritesh Harjani
b1880905a1 ext4: check for non-zero journal inum in ext4_calculate_overhead
commit f1eec3b0d0a849996ebee733b053efa71803dad5 upstream.

While calculating overhead for internal journal, also check
that j_inum shouldn't be 0. Otherwise we get below error with
xfstests generic/050 with external journal (XXX_LOGDEV config) enabled.

It could be simply reproduced with loop device with an external journal
and marking blockdev as RO before mounting.

[ 3337.146838] EXT4-fs error (device pmem1p2): ext4_get_journal_inode:4634: comm mount: inode #0: comm mount: iget: illegal inode #
------------[ cut here ]------------
generic_make_request: Trying to write to read-only block-device pmem1p2 (partno 2)
WARNING: CPU: 107 PID: 115347 at block/blk-core.c:788 generic_make_request_checks+0x6b4/0x7d0
CPU: 107 PID: 115347 Comm: mount Tainted: G             L   --------- -t - 4.18.0-167.el8.ppc64le #1
NIP:  c0000000006f6d44 LR: c0000000006f6d40 CTR: 0000000030041dd4
<...>
NIP [c0000000006f6d44] generic_make_request_checks+0x6b4/0x7d0
LR [c0000000006f6d40] generic_make_request_checks+0x6b0/0x7d0
<...>
Call Trace:
generic_make_request_checks+0x6b0/0x7d0 (unreliable)
generic_make_request+0x3c/0x420
submit_bio+0xd8/0x200
submit_bh_wbc+0x1e8/0x250
__sync_dirty_buffer+0xd0/0x210
ext4_commit_super+0x310/0x420 [ext4]
__ext4_error+0xa4/0x1e0 [ext4]
__ext4_iget+0x388/0xe10 [ext4]
ext4_get_journal_inode+0x40/0x150 [ext4]
ext4_calculate_overhead+0x5a8/0x610 [ext4]
ext4_fill_super+0x3188/0x3260 [ext4]
mount_bdev+0x778/0x8f0
ext4_mount+0x28/0x50 [ext4]
mount_fs+0x74/0x230
vfs_kern_mount.part.6+0x6c/0x250
do_mount+0x2fc/0x1280
sys_mount+0x158/0x180
system_call+0x5c/0x70
EXT4-fs (pmem1p2): no journal found
EXT4-fs (pmem1p2): can't get journal size
EXT4-fs (pmem1p2): mounted filesystem without journal. Opts: dax,norecovery

Fixes: 3c816ded78bb ("ext4: use journal inode to determine journal overhead")
Reported-by: Harish Sriram <harish@linux.ibm.com>
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200316093038.25485-1-riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:19 +02:00
Colin Ian King
5a905c2d2c ext4: unsigned int compared against zero
commit fbbbbd2f28aec991f3fbc248df211550fbdfd58c upstream.

There are two cases where u32 variables n and err are being checked
for less than zero error values, the checks is always false because
the variables are not signed. Fix this by making the variables ints.

Addresses-Coverity: ("Unsigned compared against 0")
Fixes: 345c0dbf3a30 ("ext4: protect journal inode's blocks using block_validity")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Ashwin H <ashwinh@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:19 +02:00
Theodore Ts'o
12140f9b8f ext4: fix block validity checks for journal inodes using indirect blocks
commit 170417c8c7bb2cbbdd949bf5c443c0c8f24a203b upstream.

Commit 345c0dbf3a30 ("ext4: protect journal inode's blocks using
block_validity") failed to add an exception for the journal inode in
ext4_check_blockref(), which is the function used by ext4_get_branch()
for indirect blocks.  This caused attempts to read from the ext3-style
journals to fail with:

[  848.968550] EXT4-fs error (device sdb7): ext4_get_branch:171: inode #8: block 30343695: comm jbd2/sdb7-8: invalid block

Fix this by adding the missing exception check.

Fixes: 345c0dbf3a30 ("ext4: protect journal inode's blocks using block_validity")
Reported-by: Arthur Marsh <arthur.marsh@internode.on.net>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Ashwin H <ashwinh@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:19 +02:00
Theodore Ts'o
2130aae807 ext4: don't perform block validity checks on the journal inode
commit 0a944e8a6c66ca04c7afbaa17e22bf208a8b37f0 upstream.

Since the journal inode is already checked when we added it to the
block validity's system zone, if we check it again, we'll just trigger
a failure.

This was causing failures like this:

[   53.897001] EXT4-fs error (device sda): ext4_find_extent:909: inode
#8: comm jbd2/sda-8: pblk 121667583 bad header/extent: invalid extent entries - magic f30a, entries 8, max 340(340), depth 0(0)
[   53.931430] jbd2_journal_bmap: journal block not found at offset 49 on sda-8
[   53.938480] Aborting journal on device sda-8.

... but only if the system was under enough memory pressure that
logical->physical mapping for the journal inode gets pushed out of the
extent cache.  (This is why it wasn't noticed earlier.)

Fixes: 345c0dbf3a30 ("ext4: protect journal inode's blocks using block_validity")
Reported-by: Dan Rue <dan.rue@linaro.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Ashwin H <ashwinh@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:19 +02:00
Theodore Ts'o
a9855260fe ext4: protect journal inode's blocks using block_validity
commit 345c0dbf3a30872d9b204db96b5857cd00808cae upstream.

Add the blocks which belong to the journal inode to block_validity's
system zone so attempts to deallocate or overwrite the journal due a
corrupted file system where the journal blocks are also claimed by
another inode.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202879
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Ashwin H <ashwinh@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:18 +02:00
Theodore Ts'o
553f7c0b91 ext4: avoid declaring fs inconsistent due to invalid file handles
commit 8a363970d1dc38c4ec4ad575c862f776f468d057 upstream.

If we receive a file handle, either from NFS or open_by_handle_at(2),
and it points at an inode which has not been initialized, and the file
system has metadata checksums enabled, we shouldn't try to get the
inode, discover the checksum is invalid, and then declare the file
system as being inconsistent.

This can be reproduced by creating a test file system via "mke2fs -t
ext4 -O metadata_csum /tmp/foo.img 8M", mounting it, cd'ing into that
directory, and then running the following program.

#define _GNU_SOURCE
#include <fcntl.h>

struct handle {
	struct file_handle fh;
	unsigned char fid[MAX_HANDLE_SZ];
};

int main(int argc, char **argv)
{
	struct handle h = {{8, 1 }, { 12, }};

	open_by_handle_at(AT_FDCWD, &h.fh, O_RDONLY);
	return 0;
}

Google-Bug-Id: 120690101
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Ashwin H <ashwinh@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:18 +02:00
Theodore Ts'o
ae8bbfebb1 ext4: convert BUG_ON's to WARN_ON's in mballoc.c
[ Upstream commit 907ea529fc4c3296701d2bfc8b831dd2a8121a34 ]

If the in-core buddy bitmap gets corrupted (or out of sync with the
block bitmap), issue a WARN_ON and try to recover.  In most cases this
involves skipping trying to allocate out of a particular block group.
We can end up declaring the file system corrupted, which is fair,
since the file system probably should be checked before we proceed any
further.

Link: https://lore.kernel.org/r/20200414035649.293164-1-tytso@mit.edu
Google-Bug-Id: 34811296
Google-Bug-Id: 34639169
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-02 17:23:18 +02:00
Darrick J. Wong
83693a553a xfs: fix partially uninitialized structure in xfs_reflink_remap_extent
[ Upstream commit c142932c29e533ee892f87b44d8abc5719edceec ]

In the reflink extent remap function, it turns out that uirec (the block
mapping corresponding only to the part of the passed-in mapping that got
unmapped) was not fully initialized.  Specifically, br_state was not
being copied from the passed-in struct to the uirec.  This could lead to
unpredictable results such as the reflinked mapping being marked
unwritten in the destination file.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-02 17:23:16 +02:00
Vasily Averin
0ebb05631c nfsd: memory corruption in nfsd4_lock()
commit e1e8399eee72e9d5246d4d1bcacd793debe34dd3 upstream.

New struct nfsd4_blocked_lock allocated in find_or_allocate_block()
does not initialized nbl_list and nbl_lru.
If conflock allocation fails rollback can call list_del_init()
access uninitialized fields and corrupt memory.

v2: just initialize nbl_list and nbl_lru right after nbl allocation.

Fixes: 76d348fadff5 ("nfsd: have nfsd4_lock use blocking locks for v4.1+ lock")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:15 +02:00
Miklos Szeredi
5aae6c46a5 fuse: fix possibly missed wake-up after abort
commit 2d84a2d19b6150c6dbac1e6ebad9c82e4c123772 upstream.

In current fuse_drop_waiting() implementation it's possible that
fuse_wait_aborted() will not be woken up in the unlikely case that
fuse_abort_conn() + fuse_wait_aborted() runs in between checking
fc->connected and calling atomic_dec(&fc->num_waiting).

Do the atomic_dec_and_test() unconditionally, which also provides the
necessary barrier against reordering with the fc->connected check.

The explicit smp_mb() in fuse_wait_aborted() is not actually needed, since
the spin_unlock() in fuse_abort_conn() provides the necessary RELEASE
barrier after resetting fc->connected.  However, this is not a performance
sensitive path, and adding the explicit barrier makes it easier to
document.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: b8f95e5d13f5 ("fuse: umount should wait for all requests")
Cc: <stable@vger.kernel.org> #v4.19
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:15 +02:00
Jann Horn
f8e84d7a94 vmalloc: fix remap_vmalloc_range() bounds checks
commit bdebd6a2831b6fab69eb85cee74a8ba77f1a1cc2 upstream.

remap_vmalloc_range() has had various issues with the bounds checks it
promises to perform ("This function checks that addr is a valid
vmalloc'ed area, and that it is big enough to cover the vma") over time,
e.g.:

 - not detecting pgoff<<PAGE_SHIFT overflow

 - not detecting (pgoff<<PAGE_SHIFT)+usize overflow

 - not checking whether addr and addr+(pgoff<<PAGE_SHIFT) are the same
   vmalloc allocation

 - comparing a potentially wildly out-of-bounds pointer with the end of
   the vmalloc region

In particular, since commit fc9702273e2e ("bpf: Add mmap() support for
BPF_MAP_TYPE_ARRAY"), unprivileged users can cause kernel null pointer
dereferences by calling mmap() on a BPF map with a size that is bigger
than the distance from the start of the BPF map to the end of the
address space.

This could theoretically be used as a kernel ASLR bypass, by using
whether mmap() with a given offset oopses or returns an error code to
perform a binary search over the possible address range.

To allow remap_vmalloc_range_partial() to verify that addr and
addr+(pgoff<<PAGE_SHIFT) are in the same vmalloc region, pass the offset
to remap_vmalloc_range_partial() instead of adding it to the pointer in
remap_vmalloc_range().

In remap_vmalloc_range_partial(), fix the check against
get_vm_area_size() by using size comparisons instead of pointer
comparisons, and add checks for pgoff.

Fixes: 833423143c3a ("[PATCH] mm: introduce remap_vmalloc_range()")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Link: http://lkml.kernel.org/r/20200415222312.236431-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:10 +02:00
Piotr Krysiuk
91e997939d fs/namespace.c: fix mountpoint reference counter race
A race condition between threads updating mountpoint reference counter
affects longterm releases 4.4.220, 4.9.220, 4.14.177 and 4.19.118.

The mountpoint reference counter corruption may occur when:
* one thread increments m_count member of struct mountpoint
  [under namespace_sem, but not holding mount_lock]
    pivot_root()
* another thread simultaneously decrements the same m_count
  [under mount_lock, but not holding namespace_sem]
    put_mountpoint()
      unhash_mnt()
        umount_mnt()
          mntput_no_expire()

To fix this race condition, grab mount_lock before updating m_count in
pivot_root().

Reference: CVE-2020-12114
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Piotr Krysiuk <piotras@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:10 +02:00
Yan, Zheng
a263d5547a ceph: don't skip updating wanted caps when cap is stale
[ Upstream commit 0aa971b6fd3f92afef6afe24ef78d9bb14471519 ]

1. try_get_cap_refs() fails to get caps and finds that mds_wanted
   does not include what it wants. It returns -ESTALE.
2. ceph_get_caps() calls ceph_renew_caps(). ceph_renew_caps() finds
   that inode has cap, so it calls ceph_check_caps().
3. ceph_check_caps() finds that issued caps (without checking if it's
   stale) already includes caps wanted by open file, so it skips
   updating wanted caps.

Above events can cause an infinite loop inside ceph_get_caps().

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-02 17:23:03 +02:00
Qiujun Huang
debfa1e28e ceph: return ceph_mdsc_do_request() errors from __get_parent()
[ Upstream commit c6d50296032f0b97473eb2e274dc7cc5d0173847 ]

Return the error returned by ceph_mdsc_do_request(). Otherwise,
r_target_inode ends up being NULL this ends up returning ENOENT
regardless of the error.

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-02 17:23:03 +02:00
Dmitry Monakhov
6f362a4304 ext4: fix extent_status fragmentation for plain files
commit 4068664e3cd2312610ceac05b74c4cf1853b8325 upstream.

Extents are cached in read_extent_tree_block(); as a result, extents
are not cached for inodes with depth == 0 when we try to find the
extent using ext4_find_extent().  The result of the lookup is cached
in ext4_map_blocks() but is only a subset of the extent on disk.  As a
result, the contents of extents status cache can get very badly
fragmented for certain workloads, such as a random 4k read workload.

File size of /mnt/test is 33554432 (8192 blocks of 4096 bytes)
 ext:     logical_offset:        physical_offset: length:   expected: flags:
   0:        0..    8191:      40960..     49151:   8192:             last,eof

$ perf record -e 'ext4:ext4_es_*' /root/bin/fio --name=t --direct=0 --rw=randread --bs=4k --filesize=32M --size=32M --filename=/mnt/test
$ perf script | grep ext4_es_insert_extent | head -n 10
             fio   131 [000]    13.975421:           ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [494/1) mapped 41454 status W
             fio   131 [000]    13.975939:           ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [6064/1) mapped 47024 status W
             fio   131 [000]    13.976467:           ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [6907/1) mapped 47867 status W
             fio   131 [000]    13.976937:           ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [3850/1) mapped 44810 status W
             fio   131 [000]    13.977440:           ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [3292/1) mapped 44252 status W
             fio   131 [000]    13.977931:           ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [6882/1) mapped 47842 status W
             fio   131 [000]    13.978376:           ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [3117/1) mapped 44077 status W
             fio   131 [000]    13.978957:           ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [2896/1) mapped 43856 status W
             fio   131 [000]    13.979474:           ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [7479/1) mapped 48439 status W

Fix this by caching the extents for inodes with depth == 0 in
ext4_find_extent().

[ Renamed ext4_es_cache_extents() to ext4_cache_extents() since this
  newly added function is not in extents_cache.c, and to avoid
  potential visual confusion with ext4_es_cache_extent().  -TYT ]

Signed-off-by: Dmitry Monakhov <dmonakhov@gmail.com>
Link: https://lore.kernel.org/r/20191106122502.19986-1-dmonakhov@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:22:55 +02:00
Jan Kara
24b731dca3 ext2: fix debug reference to ext2_xattr_cache
[ Upstream commit 32302085a8d90859c40cf1a5e8313f575d06ec75 ]

Fix a debug-only build error in ext2/xattr.c:

When building without extra debugging, (and with another patch that uses
no_printk() instead of <empty> for the ext2-xattr debug-print macros,
this build error happens:

../fs/ext2/xattr.c: In function ‘ext2_xattr_cache_insert’:
../fs/ext2/xattr.c:869:18: error: ‘ext2_xattr_cache’ undeclared (first use in
this function); did you mean ‘ext2_xattr_list’?
     atomic_read(&ext2_xattr_cache->c_entry_count));

Fix the problem by removing cached entry count from the debug message
since otherwise we'd have to export the mbcache structure just for that.

Fixes: be0726d33cb8 ("ext2: convert to mbcache2")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:59:14 +02:00
Randy Dunlap
5ec603feb9 ext2: fix empty body warnings when -Wextra is used
[ Upstream commit 44a52022e7f15cbaab957df1c14f7a4f527ef7cf ]

When EXT2_ATTR_DEBUG is not defined, modify the 2 debug macros
to use the no_printk() macro instead of <nothing>.
This fixes gcc warnings when -Wextra is used:

../fs/ext2/xattr.c:252:42: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../fs/ext2/xattr.c:258:42: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../fs/ext2/xattr.c:330:42: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]
../fs/ext2/xattr.c:872:45: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]

I have verified that the only object code change (with gcc 7.5.0) is
the reversal of some instructions from 'cmp a,b' to 'cmp b,a'.

Link: https://lore.kernel.org/r/e18a7395-61fb-2093-18e8-ed4f8cf56248@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jan Kara <jack@suse.com>
Cc: linux-ext4@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:59:13 +02:00
Trond Myklebust
c08f96aeef NFS: Fix memory leaks in nfs_pageio_stop_mirroring()
[ Upstream commit 862f35c94730c9270833f3ad05bd758a29f204ed ]

If we just set the mirror count to 1 without first clearing out
the mirrors, we can leak queued up requests.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:59:13 +02:00
Eric Sandeen
cb04d34762 ext4: do not commit super on read-only bdev
[ Upstream commit c96e2b8564adfb8ac14469ebc51ddc1bfecb3ae2 ]

Under some circumstances we may encounter a filesystem error on a
read-only block device, and if we try to save the error info to the
superblock and commit it, we'll wind up with a noisy error and
backtrace, i.e.:

[ 3337.146838] EXT4-fs error (device pmem1p2): ext4_get_journal_inode:4634: comm mount: inode #0: comm mount: iget: illegal inode #
------------[ cut here ]------------
generic_make_request: Trying to write to read-only block-device pmem1p2 (partno 2)
WARNING: CPU: 107 PID: 115347 at block/blk-core.c:788 generic_make_request_checks+0x6b4/0x7d0
...

To avoid this, commit the error info in the superblock only if the
block device is writable.

Reported-by: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/4b6e774d-cc00-3469-7abb-108eb151071a@sandeen.net
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:59:12 +02:00
Misono Tomohiro
6d3a2dca54 NFS: direct.c: Fix memory leak of dreq when nfs_get_lock_context fails
[ Upstream commit 8605cf0e852af3b2c771c18417499dc4ceed03d5 ]

When dreq is allocated by nfs_direct_req_alloc(), dreq->kref is
initialized to 2. Therefore we need to call nfs_direct_req_release()
twice to release the allocated dreq. Usually it is called in
nfs_file_direct_{read, write}() and nfs_direct_complete().

However, current code only calls nfs_direct_req_relese() once if
nfs_get_lock_context() fails in nfs_file_direct_{read, write}().
So, that case would result in memory leak.

Fix this by adding the missing call.

Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:59:11 +02:00
Jan Kara
40a88da4d8 ext4: do not zeroout extents beyond i_disksize
commit 801674f34ecfed033b062a0f217506b93c8d5e8a upstream.

We do not want to create initialized extents beyond end of file because
for e2fsck it is impossible to distinguish them from a case of corrupted
file size / extent tree and so it complains like:

Inode 12, i_size is 147456, should be 163840.  Fix? no

Code in ext4_ext_convert_to_initialized() and
ext4_split_convert_extents() try to make sure it does not create
initialized extents beyond inode size however they check against
inode->i_size which is wrong. They should instead check against
EXT4_I(inode)->i_disksize which is the current inode size on disk.
That's what e2fsck is going to see in case of crash before all dirty
data is written. This bug manifests as generic/456 test failure (with
recent enough fstests where fsx got fixed to properly pass
FALLOC_KEEP_SIZE_FL flags to the kernel) when run with dioread_lock
mount option.

CC: stable@vger.kernel.org
Fixes: 21ca087a3891 ("ext4: Do not zero out uninitialized extents beyond i_size")
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20200331105016.8674-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:59:05 +02:00
Josef Bacik
32bb4ca97b btrfs: check commit root generation in should_ignore_root
commit 4d4225fc228e46948486d8b8207955f0c031b92e upstream.

Previously we would set the reloc root's last snapshot to transid - 1.
However there was a problem with doing this, and we changed it to
setting the last snapshot to the generation of the commit node of the fs
root.

This however broke should_ignore_root().  The assumption is that if we
are in a generation newer than when the reloc root was created, then we
would find the reloc root through normal backref lookups, and thus can
ignore any fs roots we find with an old enough reloc root.

Now that the last snapshot could be considerably further in the past
than before, we'd end up incorrectly ignoring an fs root.  Thus we'd
find no nodes for the bytenr we were searching for, and we'd fail to
relocate anything.  We'd loop through the relocate code again and see
that there were still used space in that block group, attempt to
relocate those bytenr's again, fail in the same way, and just loop like
this forever.  This is tricky in that we have to not modify the fs root
at all during this time, so we need to have a block group that has data
in this fs root that is not shared by any other root, which is why this
has been difficult to reproduce.

Fixes: 054570a1dc94 ("Btrfs: fix relocation incorrectly dropping data references")
CC: stable@vger.kernel.org # 4.9+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:59:04 +02:00
Josh Triplett
b845d41ffc ext4: fix incorrect inodes per group in error message
commit b9c538da4e52a7b79dfcf4cfa487c46125066dfb upstream.

If ext4_fill_super detects an invalid number of inodes per group, the
resulting error message printed the number of blocks per group, rather
than the number of inodes per group. Fix it to print the correct value.

Fixes: cd6bb35bf7f6d ("ext4: use more strict checks for inodes_per_block on mount")
Link: https://lore.kernel.org/r/8be03355983a08e5d4eed480944613454d7e2550.1585434649.git.josh@joshtriplett.org
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:59:03 +02:00
Josh Triplett
536d20c044 ext4: fix incorrect group count in ext4_fill_super error message
commit df41460a21b06a76437af040d90ccee03888e8e5 upstream.

ext4_fill_super doublechecks the number of groups before mounting; if
that check fails, the resulting error message prints the group count
from the ext4_sb_info sbi, which hasn't been set yet. Print the freshly
computed group count instead (which at that point has just been computed
in "blocks_count").

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Fixes: 4ec1102813798 ("ext4: Add sanity checks for the superblock before mounting the filesystem")
Link: https://lore.kernel.org/r/8b957cd1513fcc4550fe675c10bcce2175c33a49.1585431964.git.josh@joshtriplett.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:59:03 +02:00
zhangyi (F)
0064b0f1ff jbd2: improve comments about freeing data buffers whose page mapping is NULL
commit 780f66e59231fcf882f36c63f287252ee47cc75a upstream.

Improve comments in jbd2_journal_commit_transaction() to describe why
we don't need to clear the buffer_mapped bit for freeing file mapping
buffers whose page mapping is NULL.

Link: https://lore.kernel.org/r/20200217112706.20085-1-yi.zhang@huawei.com
Fixes: c96dceeabf76 ("jbd2: do not clear the BH_Mapped flag when forgetting a metadata buffer")
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:59:03 +02:00
Filipe Manana
68a417b5be Btrfs: fix crash during unmount due to race with delayed inode workers
[ Upstream commit f0cc2cd70164efe8f75c5d99560f0f69969c72e4 ]

During unmount we can have a job from the delayed inode items work queue
still running, that can lead to at least two bad things:

1) A crash, because the worker can try to create a transaction just
   after the fs roots were freed;

2) A transaction leak, because the worker can create a transaction
   before the fs roots are freed and just after we committed the last
   transaction and after we stopped the transaction kthread.

A stack trace example of the crash:

 [79011.691214] kernel BUG at lib/radix-tree.c:982!
 [79011.692056] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
 [79011.693180] CPU: 3 PID: 1394 Comm: kworker/u8:2 Tainted: G        W         5.6.0-rc2-btrfs-next-54 #2
 (...)
 [79011.696789] Workqueue: btrfs-delayed-meta btrfs_work_helper [btrfs]
 [79011.697904] RIP: 0010:radix_tree_tag_set+0xe7/0x170
 (...)
 [79011.702014] RSP: 0018:ffffb3c84a317ca0 EFLAGS: 00010293
 [79011.702949] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 [79011.704202] RDX: ffffb3c84a317cb0 RSI: ffffb3c84a317ca8 RDI: ffff8db3931340a0
 [79011.705463] RBP: 0000000000000005 R08: 0000000000000005 R09: ffffffff974629d0
 [79011.706756] R10: ffffb3c84a317bc0 R11: 0000000000000001 R12: ffff8db393134000
 [79011.708010] R13: ffff8db3931340a0 R14: ffff8db393134068 R15: 0000000000000001
 [79011.709270] FS:  0000000000000000(0000) GS:ffff8db3b6a00000(0000) knlGS:0000000000000000
 [79011.710699] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [79011.711710] CR2: 00007f22c2a0a000 CR3: 0000000232ad4005 CR4: 00000000003606e0
 [79011.712958] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 [79011.714205] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 [79011.715448] Call Trace:
 [79011.715925]  record_root_in_trans+0x72/0xf0 [btrfs]
 [79011.716819]  btrfs_record_root_in_trans+0x4b/0x70 [btrfs]
 [79011.717925]  start_transaction+0xdd/0x5c0 [btrfs]
 [79011.718829]  btrfs_async_run_delayed_root+0x17e/0x2b0 [btrfs]
 [79011.719915]  btrfs_work_helper+0xaa/0x720 [btrfs]
 [79011.720773]  process_one_work+0x26d/0x6a0
 [79011.721497]  worker_thread+0x4f/0x3e0
 [79011.722153]  ? process_one_work+0x6a0/0x6a0
 [79011.722901]  kthread+0x103/0x140
 [79011.723481]  ? kthread_create_worker_on_cpu+0x70/0x70
 [79011.724379]  ret_from_fork+0x3a/0x50
 (...)

The following diagram shows a sequence of steps that lead to the crash
during ummount of the filesystem:

        CPU 1                                             CPU 2                                CPU 3

 btrfs_punch_hole()
   btrfs_btree_balance_dirty()
     btrfs_balance_delayed_items()
       --> sees
           fs_info->delayed_root->items
           with value 200, which is greater
           than
           BTRFS_DELAYED_BACKGROUND (128)
           and smaller than
           BTRFS_DELAYED_WRITEBACK (512)
       btrfs_wq_run_delayed_node()
         --> queues a job for
             fs_info->delayed_workers to run
             btrfs_async_run_delayed_root()

                                                                                            btrfs_async_run_delayed_root()
                                                                                              --> job queued by CPU 1

                                                                                              --> starts picking and running
                                                                                                  delayed nodes from the
                                                                                                  prepare_list list

                                                 close_ctree()

                                                   btrfs_delete_unused_bgs()

                                                   btrfs_commit_super()

                                                     btrfs_join_transaction()
                                                       --> gets transaction N

                                                     btrfs_commit_transaction(N)
                                                       --> set transaction state
                                                        to TRANTS_STATE_COMMIT_START

                                                                                             btrfs_first_prepared_delayed_node()
                                                                                               --> picks delayed node X through
                                                                                                   the prepared_list list

                                                       btrfs_run_delayed_items()

                                                         btrfs_first_delayed_node()
                                                           --> also picks delayed node X
                                                               but through the node_list
                                                               list

                                                         __btrfs_commit_inode_delayed_items()
                                                            --> runs all delayed items from
                                                                this node and drops the
                                                                node's item count to 0
                                                                through call to
                                                                btrfs_release_delayed_inode()

                                                         --> finishes running any remaining
                                                             delayed nodes

                                                       --> finishes transaction commit

                                                   --> stops cleaner and transaction threads

                                                   btrfs_free_fs_roots()
                                                     --> frees all roots and removes them
                                                         from the radix tree
                                                         fs_info->fs_roots_radix

                                                                                             btrfs_join_transaction()
                                                                                               start_transaction()
                                                                                                 btrfs_record_root_in_trans()
                                                                                                   record_root_in_trans()
                                                                                                     radix_tree_tag_set()
                                                                                                       --> crashes because
                                                                                                           the root is not in
                                                                                                           the radix tree
                                                                                                           anymore

If the worker is able to call btrfs_join_transaction() before the unmount
task frees the fs roots, we end up leaking a transaction and all its
resources, since after the call to btrfs_commit_super() and stopping the
transaction kthread, we don't expect to have any transaction open anymore.

When this situation happens the worker has a delayed node that has no
more items to run, since the task calling btrfs_run_delayed_items(),
which is doing a transaction commit, picks the same node and runs all
its items first.

We can not wait for the worker to complete when running delayed items
through btrfs_run_delayed_items(), because we call that function in
several phases of a transaction commit, and that could cause a deadlock
because the worker calls btrfs_join_transaction() and the task doing the
transaction commit may have already set the transaction state to
TRANS_STATE_COMMIT_DOING.

Also it's not possible to get into a situation where only some of the
items of a delayed node are added to the fs/subvolume tree in the current
transaction and the remaining ones in the next transaction, because when
running the items of a delayed inode we lock its mutex, effectively
waiting for the worker if the worker is running the items of the delayed
node already.

Since this can only cause issues when unmounting a filesystem, fix it in
a simple way by waiting for any jobs on the delayed workers queue before
calling btrfs_commit_supper() at close_ctree(). This works because at this
point no one can call btrfs_btree_balance_dirty() or
btrfs_balance_delayed_items(), and if we end up waiting for any worker to
complete, btrfs_commit_super() will commit the transaction created by the
worker.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:59:00 +02:00
Simon Gander
ffdfcd878c hfsplus: fix crash and filesystem corruption when deleting files
commit 25efb2ffdf991177e740b2f63e92b4ec7d310a92 upstream.

When removing files containing extended attributes, the hfsplus driver may
remove the wrong entries from the attributes b-tree, causing major
filesystem damage and in some cases even kernel crashes.

To remove a file, all its extended attributes have to be removed as well.
The driver does this by looking up all keys in the attributes b-tree with
the cnid of the file.  Each of these entries then gets deleted using the
key used for searching, which doesn't contain the attribute's name when it
should.  Since the key doesn't contain the name, the deletion routine will
not find the correct entry and instead remove the one in front of it.  If
parent nodes have to be modified, these become corrupt as well.  This
causes invalid links and unsorted entries that not even macOS's fsck_hfs
is able to fix.

To fix this, modify the search key before an entry is deleted from the
attributes b-tree by copying the found entry's key into the search key,
therefore ensuring that the correct entry gets removed from the tree.

Signed-off-by: Simon Gander <simon@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Anton Altaparmakov <anton@tuxera.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200327155541.1521-1-simon@tuxera.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:58:59 +02:00
Changwei Ge
75ace9f0de ocfs2: no need try to truncate file beyond i_size
commit 783fda856e1034dee90a873f7654c418212d12d7 upstream.

Linux fallocate(2) with FALLOC_FL_PUNCH_HOLE mode set, its offset can
exceed the inode size.  Ocfs2 now doesn't allow that offset beyond inode
size.  This restriction is not necessary and violates fallocate(2)
semantics.

If fallocate(2) offset is beyond inode size, just return success and do
nothing further.

Otherwise, ocfs2 will crash the kernel.

  kernel BUG at fs/ocfs2//alloc.c:7264!
   ocfs2_truncate_inline+0x20f/0x360 [ocfs2]
   ocfs2_remove_inode_range+0x23c/0xcb0 [ocfs2]
   __ocfs2_change_file_space+0x4a5/0x650 [ocfs2]
   ocfs2_fallocate+0x83/0xa0 [ocfs2]
   vfs_fallocate+0x148/0x230
   SyS_fallocate+0x48/0x80
   do_syscall_64+0x79/0x170

Signed-off-by: Changwei Ge <chge@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200407082754.17565-1-chge@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:58:58 +02:00
Qian Cai
9945c406c8 ext4: fix a data race at inode->i_blocks
commit 28936b62e71e41600bab319f262ea9f9b1027629 upstream.

inode->i_blocks could be accessed concurrently as noticed by KCSAN,

 BUG: KCSAN: data-race in ext4_do_update_inode [ext4] / inode_add_bytes

 write to 0xffff9a00d4b982d0 of 8 bytes by task 22100 on cpu 118:
  inode_add_bytes+0x65/0xf0
  __inode_add_bytes at fs/stat.c:689
  (inlined by) inode_add_bytes at fs/stat.c:702
  ext4_mb_new_blocks+0x418/0xca0 [ext4]
  ext4_ext_map_blocks+0x1a6b/0x27b0 [ext4]
  ext4_map_blocks+0x1a9/0x950 [ext4]
  _ext4_get_block+0xfc/0x270 [ext4]
  ext4_get_block_unwritten+0x33/0x50 [ext4]
  __block_write_begin_int+0x22e/0xae0
  __block_write_begin+0x39/0x50
  ext4_write_begin+0x388/0xb50 [ext4]
  ext4_da_write_begin+0x35f/0x8f0 [ext4]
  generic_perform_write+0x15d/0x290
  ext4_buffered_write_iter+0x11f/0x210 [ext4]
  ext4_file_write_iter+0xce/0x9e0 [ext4]
  new_sync_write+0x29c/0x3b0
  __vfs_write+0x92/0xa0
  vfs_write+0x103/0x260
  ksys_write+0x9d/0x130
  __x64_sys_write+0x4c/0x60
  do_syscall_64+0x91/0xb05
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 read to 0xffff9a00d4b982d0 of 8 bytes by task 8 on cpu 65:
  ext4_do_update_inode+0x4a0/0xf60 [ext4]
  ext4_inode_blocks_set at fs/ext4/inode.c:4815
  ext4_mark_iloc_dirty+0xaf/0x160 [ext4]
  ext4_mark_inode_dirty+0x129/0x3e0 [ext4]
  ext4_convert_unwritten_extents+0x253/0x2d0 [ext4]
  ext4_convert_unwritten_io_end_vec+0xc5/0x150 [ext4]
  ext4_end_io_rsv_work+0x22c/0x350 [ext4]
  process_one_work+0x54f/0xb90
  worker_thread+0x80/0x5f0
  kthread+0x1cd/0x1f0
  ret_from_fork+0x27/0x50

 4 locks held by kworker/u256:0/8:
  #0: ffff9a025abc4328 ((wq_completion)ext4-rsv-conversion){+.+.}, at: process_one_work+0x443/0xb90
  #1: ffffab5a862dbe20 ((work_completion)(&ei->i_rsv_conversion_work)){+.+.}, at: process_one_work+0x443/0xb90
  #2: ffff9a025a9d0f58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2]
  #3: ffff9a00d4b985d8 (&(&ei->i_raw_lock)->rlock){+.+.}, at: ext4_do_update_inode+0xaa/0xf60 [ext4]
 irq event stamp: 3009267
 hardirqs last  enabled at (3009267): [<ffffffff980da9b7>] __find_get_block+0x107/0x790
 hardirqs last disabled at (3009266): [<ffffffff980da8f9>] __find_get_block+0x49/0x790
 softirqs last  enabled at (3009230): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c
 softirqs last disabled at (3009223): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0

 Reported by Kernel Concurrency Sanitizer on:
 CPU: 65 PID: 8 Comm: kworker/u256:0 Tainted: G L 5.6.0-rc2-next-20200221+ #7
 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019
 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work [ext4]

The plain read is outside of inode->i_lock critical section which
results in a data race. Fix it by adding READ_ONCE() there.

Link: https://lore.kernel.org/r/20200222043258.2279-1-cai@lca.pw
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:58:58 +02:00
Josef Bacik
c7b7daf956 btrfs: drop block from cache on error in relocation
commit 8e19c9732ad1d127b5575a10f4fbcacf740500ff upstream.

If we have an error while building the backref tree in relocation we'll
process all the pending edges and then free the node.  However if we
integrated some edges into the cache we'll lose our link to those edges
by simply freeing this node, which means we'll leak memory and
references to any roots that we've found.

Instead we need to use remove_backref_node(), which walks through all of
the edges that are still linked to this node and free's them up and
drops any root references we may be holding.

CC: stable@vger.kernel.org # 4.9+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:58:56 +02:00
Eric W. Biederman
110012a2c9 signal: Extend exec_id to 64bits
commit d1e7fd6462ca9fc76650fbe6ca800e35b24267da upstream.

Replace the 32bit exec_id with a 64bit exec_id to make it impossible
to wrap the exec_id counter.  With care an attacker can cause exec_id
wrap and send arbitrary signals to a newly exec'd parent.  This
bypasses the signal sending checks if the parent changes their
credentials during exec.

The severity of this problem can been seen that in my limited testing
of a 32bit exec_id it can take as little as 19s to exec 65536 times.
Which means that it can take as little as 14 days to wrap a 32bit
exec_id.  Adam Zabrocki has succeeded wrapping the self_exe_id in 7
days.  Even my slower timing is in the uptime of a typical server.
Which means self_exec_id is simply a speed bump today, and if exec
gets noticably faster self_exec_id won't even be a speed bump.

Extending self_exec_id to 64bits introduces a problem on 32bit
architectures where reading self_exec_id is no longer atomic and can
take two read instructions.  Which means that is is possible to hit
a window where the read value of exec_id does not match the written
value.  So with very lucky timing after this change this still
remains expoiltable.

I have updated the update of exec_id on exec to use WRITE_ONCE
and the read of exec_id in do_notify_parent to use READ_ONCE
to make it clear that there is no locking between these two
locations.

Link: https://lore.kernel.org/kernel-hardening/20200324215049.GA3710@pi3.com.pl
Fixes: 2.3.23pre2
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-24 07:58:54 +02:00
Josef Bacik
ce216cff2d btrfs: track reloc roots based on their commit root bytenr
[ Upstream commit ea287ab157c2816bf12aad4cece41372f9d146b4 ]

We always search the commit root of the extent tree for looking up back
references, however we track the reloc roots based on their current
bytenr.

This is wrong, if we commit the transaction between relocating tree
blocks we could end up in this code in build_backref_tree

  if (key.objectid == key.offset) {
	  /*
	   * Only root blocks of reloc trees use backref
	   * pointing to itself.
	   */
	  root = find_reloc_root(rc, cur->bytenr);
	  ASSERT(root);
	  cur->root = root;
	  break;
  }

find_reloc_root() is looking based on the bytenr we had in the commit
root, but if we've COWed this reloc root we will not find that bytenr,
and we will trip over the ASSERT(root).

Fix this by using the commit_root->start bytenr for indexing the commit
root.  Then we change the __update_reloc_root() caller to be used when
we switch the commit root for the reloc root during commit.

This fixes the panic I was seeing when we started throttling relocation
for delayed refs.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:58:49 +02:00
Josef Bacik
daa2bddfcf btrfs: remove a BUG_ON() from merge_reloc_roots()
[ Upstream commit 7b7b74315b24dc064bc1c683659061c3d48f8668 ]

This was pretty subtle, we default to reloc roots having 0 root refs, so
if we crash in the middle of the relocation they can just be deleted.
If we successfully complete the relocation operations we'll set our root
refs to 1 in prepare_to_merge() and then go on to merge_reloc_roots().

At prepare_to_merge() time if any of the reloc roots have a 0 reference
still, we will remove that reloc root from our reloc root rb tree, and
then clean it up later.

However this only happens if we successfully start a transaction.  If
we've aborted previously we will skip this step completely, and only
have reloc roots with a reference count of 0, but were never properly
removed from the reloc control's rb tree.

This isn't a problem per-se, our references are held by the list the
reloc roots are on, and by the original root the reloc root belongs to.
If we end up in this situation all the reloc roots will be added to the
dirty_reloc_list, and then properly dropped at that point.  The reloc
control will be free'd and the rb tree is no longer used.

There were two options when fixing this, one was to remove the BUG_ON(),
the other was to make prepare_to_merge() handle the case where we
couldn't start a trans handle.

IMO this is the cleaner solution.  I started with handling the error in
prepare_to_merge(), but it turned out super ugly.  And in the end this
BUG_ON() simply doesn't matter, the cleanup was happening properly, we
were just panicing because this BUG_ON() only matters in the success
case.  So I've opted to just remove it and add a comment where it was.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:58:49 +02:00
Bob Peterson
e0d199c1eb gfs2: Don't demote a glock until its revokes are written
[ Upstream commit df5db5f9ee112e76b5202fbc331f990a0fc316d6 ]

Before this patch, run_queue would demote glocks based on whether
there are any more holders. But if the glock has pending revokes that
haven't been written to the media, giving up the glock might end in
file system corruption if the revokes never get written due to
io errors, node crashes and fences, etc. In that case, another node
will replay the metadata blocks associated with the glock, but
because the revoke was never written, it could replay that block
even though the glock had since been granted to another node who
might have made changes.

This patch changes the logic in run_queue so that it never demotes
a glock until its count of pending revokes reaches zero.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-24 07:58:48 +02:00
Ilya Dryomov
1cccf9da6a ceph: canonicalize server path in place
commit b27a939e8376a3f1ed09b9c33ef44d20f18ec3d0 upstream.

syzbot reported that 4fbc0c711b24 ("ceph: remove the extra slashes in
the server path") had caused a regression where an allocation could be
done under a spinlock -- compare_mount_options() is called by sget_fc()
with sb_lock held.

We don't really need the supplied server path, so canonicalize it
in place and compare it directly.  To make this work, the leading
slash is kept around and the logic in ceph_real_mount() to skip it
is restored.  CEPH_MSG_CLIENT_SESSION now reports the same (i.e.
canonicalized) path, with the leading slash of course.

Fixes: 4fbc0c711b24 ("ceph: remove the extra slashes in the server path")
Reported-by: syzbot+98704a51af8e3d9425a9@syzkaller.appspotmail.com
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-13 10:32:57 +02:00