[ Upstream commit 56f3ce6751 ]
blkoff_off might over 512 due to fs corrupt or security
vulnerability. That should be checked before being using.
Use ENTRIES_IN_SUM to protect invalid value in cur_data_blkoff.
Signed-off-by: Ocean Chen <oceanchen@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3b2d4dcf71 ]
Since commit 10a68cdf10 (nfsd: fix performance-limiting session
calculation) (Linux 5.1-rc1 and 4.19.31), shares from NFS servers with
1 TB of memory cannot be mounted anymore. The mount just hangs on the
client.
The gist of commit 10a68cdf10 is the change below.
-avail = clamp_t(int, avail, slotsize, avail/3);
+avail = clamp_t(int, avail, slotsize, total_avail/3);
Here are the macros.
#define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <)
#define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi)
`total_avail` is 8,434,659,328 on the 1 TB machine. `clamp_t()` casts
the values to `int`, which for 32-bit integers can only hold values
−2,147,483,648 (−2^31) through 2,147,483,647 (2^31 − 1).
`avail` (in the function signature) is just 65536, so that no overflow
was happening. Before the commit the assignment would result in 21845,
and `num = 4`.
When using `total_avail`, it is causing the assignment to be
18446744072226137429 (printed as %lu), and `num` is then 4164608182.
My next guess is, that `nfsd_drc_mem_used` is then exceeded, and the
server thinks there is no memory available any more for this client.
Updating the arguments of `clamp_t()` and `min_t()` to `unsigned long`
fixes the issue.
Now, `avail = 65536` (before commit 10a68cdf10 `avail = 21845`), but
`num = 4` remains the same.
Fixes: c54f24e338 (nfsd: fix performance-limiting session calculation)
Cc: stable@vger.kernel.org
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c54f24e338 ]
We're unintentionally limiting the number of slots per nfsv4.1 session
to 10. Often more than 10 simultaneous RPCs are needed for the best
performance.
This calculation was meant to prevent any one client from using up more
than a third of the limit we set for total memory use across all clients
and sessions. Instead, it's limiting the client to a third of the
maximum for a single session.
Fix this.
Reported-by: Chris Tracy <ctracy@engr.scu.edu>
Cc: stable@vger.kernel.org
Fixes: de766e5704 "nfsd: give out fewer session slots as limit approaches"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit de766e5704 ]
Instead of granting client's full requests until we hit our DRC size
limit and then failing CREATE_SESSIONs (and hence mounts) completely,
start granting clients smaller slot tables as we approach the limit.
The factor chosen here is pretty much arbitrary.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 44d8660d3b ]
An NFSv4.1+ client negotiates the size of its duplicate reply cache size
in the initial CREATE_SESSION request. The server preallocates the
memory for the duplicate reply cache to ensure that we'll never fail to
record the response to a nonidempotent operation.
To prevent a few CREATE_SESSIONs from consuming all of memory we set an
upper limit based on nr_free_buffer_pages(). 1/2^10 has been too
limiting in practice; 1/2^7 is still less than one percent.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8fd1ab747d ]
If the server that does not implement NFSv4.1 persistent session
semantics reboots while we are performing an exclusive create,
then the return value of NFS4ERR_DELAY when we replay the open
during the grace period causes us to lose the verifier.
When the grace period expires, and we present a new verifier,
the server will then correctly reply NFS4ERR_EXIST.
This commit ensures that we always present the same verifier when
replaying the OPEN.
Reported-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 4e19d6b65f upstream.
The largedir feature was intended to allow ext4 directories to have
unmapped directory blocks (e.g., directory holes). And so the
released e2fsprogs no longer enforces this for largedir file systems;
however, the corresponding change to the kernel-side code was not made.
This commit fixes this oversight.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0bdf8a8245 upstream.
ECRYPTFS_SIZE_AND_MARKER_BYTES is type size_t, so if "rc" is negative
that gets type promoted to a high positive value and treated as success.
Fixes: 778aeb42a7 ("eCryptfs: Cleanup and optimize ecryptfs_lookup_interpose()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
[tyhicks: Use "if/else if" rather than "if/if"]
Cc: stable@vger.kernel.org
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7fa0a1da3d upstream.
Patch series "Coda updates".
The following patch series is a collection of various fixes for Coda,
most of which were collected from linux-fsdevel or linux-kernel but
which have as yet not found their way upstream.
This patch (of 22):
Various file systems expect that vma->vm_file points at their own file
handle, several use file_inode(vma->vm_file) to get at their inode or
use vma->vm_file->private_data. However the way Coda wrapped mmap on a
host file broke this assumption, vm_file was still pointing at the Coda
file and the host file systems would scribble over Coda's inode and
private file data.
This patch fixes the incorrect expectation and wraps vm_ops->open and
vm_ops->close to allow Coda to track when the vm_area_struct is
destroyed so we still release the reference on the Coda file handle at
the right time.
[This patch differs from the original upstream patch because older stable
kernels do not have the call_mmap vfs helper so we call f_ops->mmap
directly.]
Link: http://lkml.kernel.org/r/0e850c6e59c0b147dc2dcd51a3af004c948c3697.1558117389.git.jaharkes@cs.cmu.edu
Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Mikko Rapeli <mikko.rapeli@iki.fi>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Yann Droneaud <ydroneaud@opteya.com>
Cc: Zhouyang Jia <jiazhouyang09@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 179006688a upstream.
If the range for which we are punching a hole covers only part of a page,
we end up updating the inode item but we skip the update of the inode's
iversion, mtime and ctime. Fix that by ensuring we update those properties
of the inode.
A patch for fstests test case generic/059 that tests this as been sent
along with this fix.
Fixes: 2aaa665581 ("Btrfs: add hole punching")
Fixes: e8c1c76e80 ("Btrfs: add missing inode update when punching hole")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5ec27ec735 upstream.
Normally, the inode's i_uid/i_gid are translated relative to s_user_ns,
but this is not a correct behavior for proc. Since sysctl permission
check in test_perm is done against GLOBAL_ROOT_[UG]ID, it makes more
sense to use these values in u_[ug]id of proc inodes. In other words:
although uid/gid in the inode is not read during test_perm, the inode
logically belongs to the root of the namespace. I have confirmed this
with Eric Biederman at LPC and in this thread:
https://lore.kernel.org/lkml/87k1kzjdff.fsf@xmission.com
Consequences
============
Since the i_[ug]id values of proc nodes are not used for permissions
checks, this change usually makes no functional difference. However, it
causes an issue in a setup where:
* a namespace container is created without root user in container -
hence the i_[ug]id of proc nodes are set to INVALID_[UG]ID
* container creator tries to configure it by writing /proc/sys files,
e.g. writing /proc/sys/kernel/shmmax to configure shared memory limit
Kernel does not allow to open an inode for writing if its i_[ug]id are
invalid, making it impossible to write shmmax and thus - configure the
container.
Using a container with no root mapping is apparently rare, but we do use
this configuration at Google. Also, we use a generic tool to configure
the container limits, and the inability to write any of them causes a
failure.
History
=======
The invalid uids/gids in inodes first appeared due to 8175435777 (fs:
Update i_[ug]id_(read|write) to translate relative to s_user_ns).
However, AFAIK, this did not immediately cause any issues. The
inability to write to these "invalid" inodes was only caused by a later
commit 0bd23d09b8 (vfs: Don't modify inodes with a uid or gid unknown
to the vfs).
Tested: Used a repro program that creates a user namespace without any
mapping and stat'ed /proc/$PID/root/proc/sys/kernel/shmmax from outside.
Before the change, it shows the overflow uid, with the change it's 0.
The overflow uid indicates that the uid in the inode is not correct and
thus it is not possible to open the file for writing.
Link: http://lkml.kernel.org/r/20190708115130.250149-1-rburny@google.com
Fixes: 0bd23d09b8 ("vfs: Don't modify inodes with a uid or gid unknown to the vfs")
Signed-off-by: Radoslaw Burny <rburny@google.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: John Sperbeck <jsperbeck@google.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <stable@vger.kernel.org> [4.8+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 44942b4e45 upstream.
According to the open() manpage, Linux reserves the access mode 3
to mean "check for read and write permission on the file and return
a file descriptor that can't be used for reading or writing."
Currently, the NFSv4 code will ask the server to open the file,
and will use an incorrect share access mode of 0. Since it has
an incorrect share access mode, the client later forgets to send
a corresponding close, meaning it can leak stateids on the server.
Fixes: ce4ef7c0a8 ("NFS: Split out NFS v4 file operations")
Cc: stable@vger.kernel.org # 3.6+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6631142229 ]
wbc_account_io() collects information on cgroup ownership of writeback
pages to determine which cgroup should own the inode. Pages can stay
associated with dead memcgs but we want to avoid attributing IOs to
dead blkcgs as much as possible as the association is likely to be
stale. However, currently, pages associated with dead memcgs
contribute to the accounting delaying and/or confusing the
arbitration.
Fix it by ignoring pages associated with dead memcgs.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 5858bdad4d upstream.
The directory may have been removed when entering
fscrypt_ioctl_set_policy(). If so, the empty_dir() check will return
error for ext4 file system.
ext4_rmdir() sets i_size = 0, then ext4_empty_dir() reports an error
because 'inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2)'. If
the fs is mounted with errors=panic, it will trigger a panic issue.
Add the check IS_DEADDIR() to fix this problem.
Fixes: 9bd8212f98 ("ext4 crypto: add encryption policy and password salt support")
Cc: <stable@vger.kernel.org> # v4.1+
Signed-off-by: Hongjie Fang <hongjiefang@asrmicro.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fa33cdbf3e upstream.
In some cases, using the 'truncate' command to extend a UDF file results
in a mismatch between the length of the file's extents (specifically, due
to incorrect length of the final NOT_ALLOCATED extent) and the information
(file) length. The discrepancy can prevent other operating systems
(i.e., Windows 10) from opening the file.
Two particular errors have been observed when extending a file:
1. The final extent is larger than it should be, having been rounded up
to a multiple of the block size.
B. The final extent is not shorter than it should be, due to not having
been updated when the file's information length was increased.
[JK: simplified udf_do_extend_final_block(), fixed up some types]
Fixes: 2c948b3f86 ("udf: Avoid IO in udf_clear_inode")
CC: stable@vger.kernel.org
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Link: https://lore.kernel.org/r/1561948775-5878-1-git-send-email-steve@digidescorp.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit debd1c065d upstream.
Recent FITRIM work, namely bbbf7243d6 ("btrfs: combine device update
operations during transaction commit") combined the way certain
operations are recoded in a transaction. As a result an ASSERT was added
in dev_replace_finish to ensure the new code works correctly.
Unfortunately I got reports that it's possible to trigger the assert,
meaning that during a device replace it's possible to have an unfinished
chunk allocation on the source device.
This is supposed to be prevented by the fact that a transaction is
committed before finishing the replace oepration and alter acquiring the
chunk mutex. This is not sufficient since by the time the transaction is
committed and the chunk mutex acquired it's possible to allocate a chunk
depending on the workload being executed on the replaced device. This
bug has been present ever since device replace was introduced but there
was never code which checks for it.
The correct way to fix is to ensure that there is no pending device
modification operation when the chunk mutex is acquire and if there is
repeat transaction commit. Unfortunately it's not possible to just
exclude the source device from btrfs_fs_devices::dev_alloc_list since
this causes ENOSPC to be hit in transaction commit.
Fixing that in another way would need to add special cases to handle the
last writes and forbid new ones. The looped transaction fix is more
obvious, and can be easily backported. The runtime of dev-replace is
long so there's no noticeable delay caused by that.
Reported-by: David Sterba <dsterba@suse.com>
Fixes: 391cd9df81 ("Btrfs: fix unprotected alloc list insertion during the finishing procedure of replace")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Nikolay Borisov <nborisov@suse.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>
commit 867bfa4a5f upstream.
load_flat_shared_library() is broken: It only calls load_flat_file() if
prepare_binprm() returns zero, but prepare_binprm() returns the number of
bytes read - so this only happens if the file is empty.
Instead, call into load_flat_file() if the number of bytes read is
non-negative. (Even if the number of bytes is zero - in that case,
load_flat_file() will see nullbytes and return a nice -ENOEXEC.)
In addition, remove the code related to bprm creds and stop using
prepare_binprm() - this code is loading a library, not a main executable,
and it only actually uses the members "buf", "file" and "filename" of the
linux_binprm struct. Instead, call kernel_read() directly.
Link: http://lkml.kernel.org/r/20190524201817.16509-1-jannh@google.com
Fixes: 287980e49f ("remove lots of IS_ERR_VALUE abuses")
Signed-off-by: Jann Horn <jannh@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c4e0540d0a upstream.
Currently, btrfs does not consult seed devices to start readahead. As a
result, if readahead zone is added to the seed devices, btrfs_reada_wait()
indefinitely wait for the reada_ctl to finish.
You can reproduce the hung by modifying btrfs/163 to have larger initial
file size (e.g. xfs_io pwrite 4M instead of current 256K).
Fixes: 7414a03fbf ("btrfs: initial readahead code and prototypes")
Cc: stable@vger.kernel.org # 3.2+: ce7791ffee: Btrfs: fix race between readahead and device replace/removal
Cc: stable@vger.kernel.org # 3.2+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f69e749a49 upstream.
file_remove_privs() might be called for non-regular files, e.g.
blkdev inode. There is no reason to do its job on things
like blkdev inodes, pipes, or cdevs. Hence, abort if
file does not refer to a regular inode.
AV: more to the point, for devices there might be any number of
inodes refering to given device. Which one to strip the permissions
from, even if that made any sense in the first place? All of them
will be observed with contents modified, after all.
Found by LockDoc (Alexander Lochmann, Horst Schirmeier and Olaf
Spinczyk)
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Alexander Lochmann <alexander.lochmann@tu-dortmund.de>
Signed-off-by: Horst Schirmeier <horst.schirmeier@tu-dortmund.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Zubin Mithra <zsm@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f6122ed2a4 ]
In the vfs_statx() context, during path lookup, the dentry gets
added to sd->s_dentry via configfs_attach_attr(). In the end,
vfs_statx() kills the dentry by calling path_put(), which invokes
configfs_d_iput(). Ideally, this dentry must be removed from
sd->s_dentry but it doesn't if the sd->s_count >= 3. As a result,
sd->s_dentry is holding reference to a stale dentry pointer whose
memory is already freed up. This results in use-after-free issue,
when this stale sd->s_dentry is accessed later in
configfs_readdir() path.
This issue can be easily reproduced, by running the LTP test case -
sh fs_racer_file_list.sh /config
(https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/fs/racer/fs_racer_file_list.sh)
Fixes: 76ae281f63 ('configfs: fix race between dentry put and lookup')
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit be99ca2716 upstream.
ocfs2_dentry_attach_lock() can be executed in parallel threads against the
same dentry. Make that race safe. The race is like this:
thread A thread B
(A1) enter ocfs2_dentry_attach_lock,
seeing dentry->d_fsdata is NULL,
and no alias found by
ocfs2_find_local_alias, so kmalloc
a new ocfs2_dentry_lock structure
to local variable "dl", dl1
.....
(B1) enter ocfs2_dentry_attach_lock,
seeing dentry->d_fsdata is NULL,
and no alias found by
ocfs2_find_local_alias so kmalloc
a new ocfs2_dentry_lock structure
to local variable "dl", dl2.
......
(A2) set dentry->d_fsdata with dl1,
call ocfs2_dentry_lock() and increase
dl1->dl_lockres.l_ro_holders to 1 on
success.
......
(B2) set dentry->d_fsdata with dl2
call ocfs2_dentry_lock() and increase
dl2->dl_lockres.l_ro_holders to 1 on
success.
......
(A3) call ocfs2_dentry_unlock()
and decrease
dl2->dl_lockres.l_ro_holders to 0
on success.
....
(B3) call ocfs2_dentry_unlock(),
decreasing
dl2->dl_lockres.l_ro_holders, but
see it's zero now, panic
Link: http://lkml.kernel.org/r/20190529174636.22364-1-wen.gang.wang@oracle.com
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Reported-by: Daniel Sobe <daniel.sobe@nxp.com>
Tested-by: Daniel Sobe <daniel.sobe@nxp.com>
Reviewed-by: Changwei Ge <gechangwei@live.cn>
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: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0b8f62625d ]
A fuzzer recently triggered lockdep warnings about potential sb_writers
deadlocks caused by fh_want_write().
Looks like we aren't careful to pair each fh_want_write() with an
fh_drop_write().
It's not normally a problem since fh_put() will call fh_drop_write() for
us. And was OK for NFSv3 where we'd do one operation that might call
fh_want_write(), and then put the filehandle.
But an NFSv4 protocol fuzzer can do weird things like call unlink twice
in a compound, and then we get into trouble.
I'm a little worried about this approach of just leaving everything to
fh_put(). But I think there are probably a lot of
fh_want_write()/fh_drop_write() imbalances so for now I think we need it
to be more forgiving.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7640682e67 ]
FUSE filesystem server and kernel client negotiate during initialization
phase, what should be the maximum write size the client will ever issue.
Correspondingly the filesystem server then queues sys_read calls to read
requests with buffer capacity large enough to carry request header + that
max_write bytes. A filesystem server is free to set its max_write in
anywhere in the range between [1*page, fc->max_pages*page]. In particular
go-fuse[2] sets max_write by default as 64K, wheres default fc->max_pages
corresponds to 128K. Libfuse also allows users to configure max_write, but
by default presets it to possible maximum.
If max_write is < fc->max_pages*page, and in NOTIFY_RETRIEVE handler we
allow to retrieve more than max_write bytes, corresponding prepared
NOTIFY_REPLY will be thrown away by fuse_dev_do_read, because the
filesystem server, in full correspondence with server/client contract, will
be only queuing sys_read with ~max_write buffer capacity, and
fuse_dev_do_read throws away requests that cannot fit into server request
buffer. In turn the filesystem server could get stuck waiting indefinitely
for NOTIFY_REPLY since NOTIFY_RETRIEVE handler returned OK which is
understood by clients as that NOTIFY_REPLY was queued and will be sent
back.
Cap requested size to negotiate max_write to avoid the problem. This
aligns with the way NOTIFY_RETRIEVE handler works, which already
unconditionally caps requested retrieve size to fuse_conn->max_pages. This
way it should not hurt NOTIFY_RETRIEVE semantic if we return less data than
was originally requested.
Please see [1] for context where the problem of stuck filesystem was hit
for real, how the situation was traced and for more involving patch that
did not make it into the tree.
[1] https://marc.info/?l=linux-fsdevel&m=155057023600853&w=2
[2] https://github.com/hanwen/go-fuse
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Cc: Jakob Unterwurzacher <jakobunt@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e95bcdb2fe ]
As Jungyeon reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=203233
- Overview
When mounting the attached crafted image and running program, following errors are reported.
Additionally, it hangs on sync after running program.
The image is intentionally fuzzed from a normal f2fs image for testing.
Compile options for F2FS are as follows.
CONFIG_F2FS_FS=y
CONFIG_F2FS_STAT_FS=y
CONFIG_F2FS_FS_XATTR=y
CONFIG_F2FS_FS_POSIX_ACL=y
CONFIG_F2FS_CHECK_FS=y
- Reproduces
cc poc_13.c
mkdir test
mount -t f2fs tmp.img test
cp a.out test
cd test
sudo ./a.out
sync
- Kernel messages
F2FS-fs (sdb): Bitmap was wrongly set, blk:4608
kernel BUG at fs/f2fs/segment.c:2102!
RIP: 0010:update_sit_entry+0x394/0x410
Call Trace:
f2fs_allocate_data_block+0x16f/0x660
do_write_page+0x62/0x170
f2fs_do_write_node_page+0x33/0xa0
__write_node_page+0x270/0x4e0
f2fs_sync_node_pages+0x5df/0x670
f2fs_write_checkpoint+0x372/0x1400
f2fs_sync_fs+0xa3/0x130
f2fs_do_sync_file+0x1a6/0x810
do_fsync+0x33/0x60
__x64_sys_fsync+0xb/0x10
do_syscall_64+0x43/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
sit.vblocks and sum valid block count in sit.valid_map may be
inconsistent, segment w/ zero vblocks will be treated as free
segment, while allocating in free segment, we may allocate a
free block, if its bitmap is valid previously, it can cause
kernel crash due to bitmap verification failure.
Anyway, to avoid further serious metadata inconsistence and
corruption, it is necessary and worth to detect SIT
inconsistence. So let's enable check_block_count() to verify
vblocks and valid_map all the time rather than do it only
CONFIG_F2FS_CHECK_FS is enabled.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 546d22f070 ]
As Jungyeon reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=203217
- Overview
When mounting the attached crafted image and running program, I got this error.
Additionally, it hangs on sync after running the program.
The image is intentionally fuzzed from a normal f2fs image for testing and I enabled option CONFIG_F2FS_CHECK_FS on.
- Reproduces
cc poc_test_05.c
mkdir test
mount -t f2fs tmp.img test
sudo ./a.out
sync
- Messages
kernel BUG at fs/f2fs/inode.c:707!
RIP: 0010:f2fs_evict_inode+0x33f/0x3a0
Call Trace:
evict+0xba/0x180
f2fs_iget+0x598/0xdf0
f2fs_lookup+0x136/0x320
__lookup_slow+0x92/0x140
lookup_slow+0x30/0x50
walk_component+0x1c1/0x350
path_lookupat+0x62/0x200
filename_lookup+0xb3/0x1a0
do_readlinkat+0x56/0x110
__x64_sys_readlink+0x16/0x20
do_syscall_64+0x43/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
During inode loading, __recover_inline_status() can recovery inode status
and set inode dirty, once we failed in following process, it will fail
the check in f2fs_evict_inode, result in trigger BUG_ON().
Let's clear dirty inode in error path of f2fs_iget() to avoid panic.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 22d61e286e ]
As Jungyeon reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=203227
- Overview
When mounting the attached crafted image, following errors are reported.
Additionally, it hangs on sync after trying to mount it.
The image is intentionally fuzzed from a normal f2fs image for testing.
Compile options for F2FS are as follows.
CONFIG_F2FS_FS=y
CONFIG_F2FS_STAT_FS=y
CONFIG_F2FS_FS_XATTR=y
CONFIG_F2FS_FS_POSIX_ACL=y
CONFIG_F2FS_CHECK_FS=y
- Reproduces
mkdir test
mount -t f2fs tmp.img test
sync
- Messages
kernel BUG at fs/f2fs/recovery.c:549!
RIP: 0010:recover_data+0x167a/0x1780
Call Trace:
f2fs_recover_fsync_data+0x613/0x710
f2fs_fill_super+0x1043/0x1aa0
mount_bdev+0x16d/0x1a0
mount_fs+0x4a/0x170
vfs_kern_mount+0x5d/0x100
do_mount+0x200/0xcf0
ksys_mount+0x79/0xc0
__x64_sys_mount+0x1c/0x20
do_syscall_64+0x43/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
During recovery, if ofs_of_node is inconsistent in between recovered
node page and original checkpointed node page, let's just fail recovery
instead of making kernel panic.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit bbd84f3365 upstream.
Starting from commit 9c225f2655 ("vfs: atomic f_pos accesses as per
POSIX") files opened even via nonseekable_open gate read and write via lock
and do not allow them to be run simultaneously. This can create read vs
write deadlock if a filesystem is trying to implement a socket-like file
which is intended to be simultaneously used for both read and write from
filesystem client. See commit 10dce8af34 ("fs: stream_open - opener for
stream-like files so that read and write can run simultaneously without
deadlock") for details and e.g. commit 581d21a2d0 ("xenbus: fix deadlock
on writes to /proc/xen/xenbus") for a similar deadlock example on
/proc/xen/xenbus.
To avoid such deadlock it was tempting to adjust fuse_finish_open to use
stream_open instead of nonseekable_open on just FOPEN_NONSEEKABLE flags,
but grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
and in particular GVFS which actually uses offset in its read and write
handlers
https://codesearch.debian.net/search?q=-%3Enonseekable+%3Dhttps://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481
so if we would do such a change it will break a real user.
Add another flag (FOPEN_STREAM) for filesystem servers to indicate that the
opened handler is having stream-like semantics; does not use file position
and thus the kernel is free to issue simultaneous read and write request on
opened file handle.
This patch together with stream_open() should be added to stable kernels
starting from v3.14+. This will allow to patch OSSPD and other FUSE
filesystems that provide stream-like files to return FOPEN_STREAM |
FOPEN_NONSEEKABLE in open handler and this way avoid the deadlock on all
kernel versions. This should work because fuse_finish_open ignores unknown
open flags returned from a filesystem and so passing FOPEN_STREAM to a
kernel that is not aware of this flag cannot hurt. In turn the kernel that
is not aware of FOPEN_STREAM will be < v3.14 where just FOPEN_NONSEEKABLE
is sufficient to implement streams without read vs write deadlock.
Cc: stable@vger.kernel.org # v3.14+
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 10dce8af34 upstream.
Commit 9c225f2655 ("vfs: atomic f_pos accesses as per POSIX") added
locking for file.f_pos access and in particular made concurrent read and
write not possible - now both those functions take f_pos lock for the
whole run, and so if e.g. a read is blocked waiting for data, write will
deadlock waiting for that read to complete.
This caused regression for stream-like files where previously read and
write could run simultaneously, but after that patch could not do so
anymore. See e.g. commit 581d21a2d0 ("xenbus: fix deadlock on writes
to /proc/xen/xenbus") which fixes such regression for particular case of
/proc/xen/xenbus.
The patch that added f_pos lock in 2014 did so to guarantee POSIX thread
safety for read/write/lseek and added the locking to file descriptors of
all regular files. In 2014 that thread-safety problem was not new as it
was already discussed earlier in 2006.
However even though 2006'th version of Linus's patch was adding f_pos
locking "only for files that are marked seekable with FMODE_LSEEK (thus
avoiding the stream-like objects like pipes and sockets)", the 2014
version - the one that actually made it into the tree as 9c225f2655 -
is doing so irregardless of whether a file is seekable or not.
See
https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/https://lwn.net/Articles/180387https://lwn.net/Articles/180396
for historic context.
The reason that it did so is, probably, that there are many files that
are marked non-seekable, but e.g. their read implementation actually
depends on knowing current position to correctly handle the read. Some
examples:
kernel/power/user.c snapshot_read
fs/debugfs/file.c u32_array_read
fs/fuse/control.c fuse_conn_waiting_read + ...
drivers/hwmon/asus_atk0110.c atk_debugfs_ggrp_read
arch/s390/hypfs/inode.c hypfs_read_iter
...
Despite that, many nonseekable_open users implement read and write with
pure stream semantics - they don't depend on passed ppos at all. And for
those cases where read could wait for something inside, it creates a
situation similar to xenbus - the write could be never made to go until
read is done, and read is waiting for some, potentially external, event,
for potentially unbounded time -> deadlock.
Besides xenbus, there are 14 such places in the kernel that I've found
with semantic patch (see below):
drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write()
drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write()
drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write()
drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write()
net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write()
drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write()
drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write()
drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write()
net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write()
drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write()
drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write()
drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write()
drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write()
drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write()
In addition to the cases above another regression caused by f_pos
locking is that now FUSE filesystems that implement open with
FOPEN_NONSEEKABLE flag, can no longer implement bidirectional
stream-like files - for the same reason as above e.g. read can deadlock
write locking on file.f_pos in the kernel.
FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f7 ("fuse:
implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp
in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and
write routines not depending on current position at all, and with both
read and write being potentially blocking operations:
See
https://github.com/libfuse/osspdhttps://lwn.net/Articles/308445https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1406https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1438-L1477https://github.com/libfuse/osspd/blob/14a9cff0/osspd.c#L1479-L1510
Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as
"somewhat pipe-like files ..." with read handler not using offset.
However that test implements only read without write and cannot exercise
the deadlock scenario:
https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216
I've actually hit the read vs write deadlock for real while implementing
my FUSE filesystem where there is /head/watch file, for which open
creates separate bidirectional socket-like stream in between filesystem
and its user with both read and write being later performed
simultaneously. And there it is semantically not easy to split the
stream into two separate read-only and write-only channels:
https://lab.nexedi.com/kirr/wendelin.core/blob/f13aa600/wcfs/wcfs.go#L88-169
Let's fix this regression. The plan is:
1. We can't change nonseekable_open to include &~FMODE_ATOMIC_POS -
doing so would break many in-kernel nonseekable_open users which
actually use ppos in read/write handlers.
2. Add stream_open() to kernel to open stream-like non-seekable file
descriptors. Read and write on such file descriptors would never use
nor change ppos. And with that property on stream-like files read and
write will be running without taking f_pos lock - i.e. read and write
could be running simultaneously.
3. With semantic patch search and convert to stream_open all in-kernel
nonseekable_open users for which read and write actually do not
depend on ppos and where there is no other methods in file_operations
which assume @offset access.
4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via
steam_open if that bit is present in filesystem open reply.
It was tempting to change fs/fuse/ open handler to use stream_open
instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but
grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
and in particular GVFS which actually uses offset in its read and
write handlers
https://codesearch.debian.net/search?q=-%3Enonseekable+%3Dhttps://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481
so if we would do such a change it will break a real user.
5. Add stream_open and FOPEN_STREAM handling to stable kernels starting
from v3.14+ (the kernel where 9c225f2655 first appeared).
This will allow to patch OSSPD and other FUSE filesystems that
provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE
in their open handler and this way avoid the deadlock on all kernel
versions. This should work because fs/fuse/ ignores unknown open
flags returned from a filesystem and so passing FOPEN_STREAM to a
kernel that is not aware of this flag cannot hurt. In turn the kernel
that is not aware of FOPEN_STREAM will be < v3.14 where just
FOPEN_NONSEEKABLE is sufficient to implement streams without read vs
write deadlock.
This patch adds stream_open, converts /proc/xen/xenbus to it and adds
semantic patch to automatically locate in-kernel places that are either
required to be converted due to read vs write deadlock, or that are just
safe to be converted because read and write do not use ppos and there
are no other funky methods in file_operations.
Regarding semantic patch I've verified each generated change manually -
that it is correct to convert - and each other nonseekable_open instance
left - that it is either not correct to convert there, or that it is not
converted due to current stream_open.cocci limitations.
The script also does not convert files that should be valid to convert,
but that currently have .llseek = noop_llseek or generic_file_llseek for
unknown reason despite file being opened with nonseekable_open (e.g.
drivers/input/mousedev.c)
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yongzhi Pan <panyongzhi@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Nikolaus Rath <Nikolaus@rath.org>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 15fab63e1e upstream.
Change pipe_buf_get() to return a bool indicating whether it succeeded
in raising the refcount of the page (if the thing in the pipe is a page).
This removes another mechanism for overflowing the page refcount. All
callers converted to handle a failure.
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 31fad7d41e upstream.
In cifs_read_allocate_pages, in case of ENOMEM, we go through
whole rdata->pages array but we have failed the allocation before
nr_pages, therefore we may end up calling put_page with NULL
pointer, causing oops
Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 06989c799f upstream.
When syncing the log, the final phase of a fsync operation, we need to
either create a log root's item or update the existing item in the log
tree of log roots, and that depends on the current value of the log
root's log_transid - if it's 1 we need to create the log root item,
otherwise it must exist already and we update it. Since there is no
synchronization between updating the log_transid and checking it for
deciding whether the log root's item needs to be created or updated, we
end up with a tiny race window that results in attempts to update the
item to fail because the item was not yet created:
CPU 1 CPU 2
btrfs_sync_log()
lock root->log_mutex
set log root's log_transid to 1
unlock root->log_mutex
btrfs_sync_log()
lock root->log_mutex
sets log root's
log_transid to 2
unlock root->log_mutex
update_log_root()
sees log root's log_transid
with a value of 2
calls btrfs_update_root(),
which fails with -EUCLEAN
and causes transaction abort
Until recently the race lead to a BUG_ON at btrfs_update_root(), but after
the recent commit 7ac1e464c4 ("btrfs: Don't panic when we can't find a
root key") we just abort the current transaction.
A sample trace of the BUG_ON() on a SLE12 kernel:
------------[ cut here ]------------
kernel BUG at ../fs/btrfs/root-tree.c:157!
Oops: Exception in kernel mode, sig: 5 [#1]
SMP NR_CPUS=2048 NUMA pSeries
(...)
Supported: Yes, External
CPU: 78 PID: 76303 Comm: rtas_errd Tainted: G X 4.4.156-94.57-default #1
task: c00000ffa906d010 ti: c00000ff42b08000 task.ti: c00000ff42b08000
NIP: d000000036ae5cdc LR: d000000036ae5cd8 CTR: 0000000000000000
REGS: c00000ff42b0b860 TRAP: 0700 Tainted: G X (4.4.156-94.57-default)
MSR: 8000000002029033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 22444484 XER: 20000000
CFAR: d000000036aba66c SOFTE: 1
GPR00: d000000036ae5cd8 c00000ff42b0bae0 d000000036bda220 0000000000000054
GPR04: 0000000000000001 0000000000000000 c00007ffff8d37c8 0000000000000000
GPR08: c000000000e19c00 0000000000000000 0000000000000000 3736343438312079
GPR12: 3930373337303434 c000000007a3a800 00000000007fffff 0000000000000023
GPR16: c00000ffa9d26028 c00000ffa9d261f8 0000000000000010 c00000ffa9d2ab28
GPR20: c00000ff42b0bc48 0000000000000001 c00000ff9f0d9888 0000000000000001
GPR24: c00000ffa9d26000 c00000ffa9d261e8 c00000ffa9d2a800 c00000ff9f0d9888
GPR28: c00000ffa9d26028 c00000ffa9d2aa98 0000000000000001 c00000ffa98f5b20
NIP [d000000036ae5cdc] btrfs_update_root+0x25c/0x4e0 [btrfs]
LR [d000000036ae5cd8] btrfs_update_root+0x258/0x4e0 [btrfs]
Call Trace:
[c00000ff42b0bae0] [d000000036ae5cd8] btrfs_update_root+0x258/0x4e0 [btrfs] (unreliable)
[c00000ff42b0bba0] [d000000036b53610] btrfs_sync_log+0x2d0/0xc60 [btrfs]
[c00000ff42b0bce0] [d000000036b1785c] btrfs_sync_file+0x44c/0x4e0 [btrfs]
[c00000ff42b0bd80] [c00000000032e300] vfs_fsync_range+0x70/0x120
[c00000ff42b0bdd0] [c00000000032e44c] do_fsync+0x5c/0xb0
[c00000ff42b0be10] [c00000000032e8dc] SyS_fdatasync+0x2c/0x40
[c00000ff42b0be30] [c000000000009488] system_call+0x3c/0x100
Instruction dump:
7f43d378 4bffebb9 60000000 88d90008 3d220000 e8b90000 3b390009 e87a01f0
e8898e08 e8f90000 4bfd48e5 60000000 <0fe00000> e95b0060 39200004 394a0ea0
---[ end trace 8f2dc8f919cabab8 ]---
So fix this by doing the check of log_transid and updating or creating the
log root's item while holding the root's log_mutex.
Fixes: 7237f18336 ("Btrfs: fix tree logs parallel sync")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7881ef3f33 ]
Under certain conditions, lru_count may drop below zero resulting in
a large amount of log spam like this:
vmscan: shrink_slab: gfs2_dump_glock+0x3b0/0x630 [gfs2] \
negative objects to delete nr=-1
This happens as follows:
1) A glock is moved from lru_list to the dispose list and lru_count is
decremented.
2) The dispose function calls cond_resched() and drops the lru lock.
3) Another thread takes the lru lock and tries to add the same glock to
lru_list, checking if the glock is on an lru list.
4) It is on a list (actually the dispose list) and so it avoids
incrementing lru_count.
5) The glock is moved to lru_list.
5) The original thread doesn't dispose it because it has been re-added
to the lru list but the lru_count has still decreased by one.
Fix by checking if the LRU flag is set on the glock rather than checking
if the glock is on some list and rearrange the code so that the LRU flag
is added/removed precisely when the glock is added/removed from lru_list.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This reverts commit 038ec2c13e.
There is currently no corresponding patch in master due to additional
changes that would be significantly different from plain revert in the
respective stable branch.
The range argument was not handled correctly and could cause trim to
overlap allocated areas or reach beyond the end of the device. The
address space that fitrim normally operates on is in logical
coordinates, while the discards are done on the physical device extents.
This distinction cannot be made with the current ioctl interface and
caused the confusion.
The bug depends on the layout of block groups and does not always
happen. The whole-fs trim (run by default by the fstrim tool) is not
affected.
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1b426bac66 upstream.
hugetlb uses a fault mutex hash table to prevent page faults of the
same pages concurrently. The key for shared and private mappings is
different. Shared keys off address_space and file index. Private keys
off mm and virtual address. Consider a private mappings of a populated
hugetlbfs file. A fault will map the page from the file and if needed
do a COW to map a writable page.
Hugetlbfs hole punch uses the fault mutex to prevent mappings of file
pages. It uses the address_space file index key. However, private
mappings will use a different key and could race with this code to map
the file page. This causes problems (BUG) for the page cache remove
code as it expects the page to be unmapped. A sample stack is:
page dumped because: VM_BUG_ON_PAGE(page_mapped(page))
kernel BUG at mm/filemap.c:169!
...
RIP: 0010:unaccount_page_cache_page+0x1b8/0x200
...
Call Trace:
__delete_from_page_cache+0x39/0x220
delete_from_page_cache+0x45/0x70
remove_inode_hugepages+0x13c/0x380
? __add_to_page_cache_locked+0x162/0x380
hugetlbfs_fallocate+0x403/0x540
? _cond_resched+0x15/0x30
? __inode_security_revalidate+0x5d/0x70
? selinux_file_permission+0x100/0x130
vfs_fallocate+0x13f/0x270
ksys_fallocate+0x3c/0x80
__x64_sys_fallocate+0x1a/0x20
do_syscall_64+0x5b/0x180
entry_SYSCALL_64_after_hwframe+0x44/0xa9
There seems to be another potential COW issue/race with this approach
of different private and shared keys as noted in commit 8382d914eb
("mm, hugetlb: improve page-fault scalability").
Since every hugetlb mapping (even anon and private) is actually a file
mapping, just use the address_space index key for all mappings. This
results in potentially more hash collisions. However, this should not
be the common case.
Link: http://lkml.kernel.org/r/20190328234704.27083-3-mike.kravetz@oracle.com
Link: http://lkml.kernel.org/r/20190412165235.t4sscoujczfhuiyt@linux-r8p5
Fixes: b5cec28d36 ("hugetlbfs: truncate_hugepages() takes a range of pages")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e32773357d upstream.
A failed call to kobject_init_and_add() must be followed by a call to
kobject_put(). Currently in the error path when adding fs_devices we
are missing this call. This could be fixed by calling
btrfs_sysfs_remove_fsid() if btrfs_sysfs_add_fsid() returns an error or
by adding a call to kobject_put() directly in btrfs_sysfs_add_fsid().
Here we choose the second option because it prevents the slightly
unusual error path handling requirements of kobject from leaking out
into btrfs functions.
Add a call to kobject_put() in the error path of kobject_add_and_init().
This causes the release method to be called if kobject_init_and_add()
fails. open_tree() is the function that calls btrfs_sysfs_add_fsid()
and the error code in this function is already written with the
assumption that the release method is called during the error path of
open_tree() (as seen by the call to btrfs_sysfs_remove_fsid() under the
fail_fsdev_sysfs label).
Cc: stable@vger.kernel.org # v4.4+
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0c713cbab6 upstream.
When we do a full fsync (the bit BTRFS_INODE_NEEDS_FULL_SYNC is set in the
inode) that happens to be ranged, which happens during a msync() or writes
for files opened with O_SYNC for example, we can end up with a corrupt log,
due to different file extent items representing ranges that overlap with
each other, or hit some assertion failures.
When doing a ranged fsync we only flush delalloc and wait for ordered
exents within that range. If while we are logging items from our inode
ordered extents for adjacent ranges complete, we end up in a race that can
make us insert the file extent items that overlap with others we logged
previously and the assertion failures.
For example, if tree-log.c:copy_items() receives a leaf that has the
following file extents items, all with a length of 4K and therefore there
is an implicit hole in the range 68K to 72K - 1:
(257 EXTENT_ITEM 64K), (257 EXTENT_ITEM 72K), (257 EXTENT_ITEM 76K), ...
It copies them to the log tree. However due to the need to detect implicit
holes, it may release the path, in order to look at the previous leaf to
detect an implicit hole, and then later it will search again in the tree
for the first file extent item key, with the goal of locking again the
leaf (which might have changed due to concurrent changes to other inodes).
However when it locks again the leaf containing the first key, the key
corresponding to the extent at offset 72K may not be there anymore since
there is an ordered extent for that range that is finishing (that is,
somewhere in the middle of btrfs_finish_ordered_io()), and it just
removed the file extent item but has not yet replaced it with a new file
extent item, so the part of copy_items() that does hole detection will
decide that there is a hole in the range starting from 68K to 76K - 1,
and therefore insert a file extent item to represent that hole, having
a key offset of 68K. After that we now have a log tree with 2 different
extent items that have overlapping ranges:
1) The file extent item copied before copy_items() released the path,
which has a key offset of 72K and a length of 4K, representing the
file range 72K to 76K - 1.
2) And a file extent item representing a hole that has a key offset of
68K and a length of 8K, representing the range 68K to 76K - 1. This
item was inserted after releasing the path, and overlaps with the
extent item inserted before.
The overlapping extent items can cause all sorts of unpredictable and
incorrect behaviour, either when replayed or if a fast (non full) fsync
happens later, which can trigger a BUG_ON() when calling
btrfs_set_item_key_safe() through __btrfs_drop_extents(), producing a
trace like the following:
[61666.783269] ------------[ cut here ]------------
[61666.783943] kernel BUG at fs/btrfs/ctree.c:3182!
[61666.784644] invalid opcode: 0000 [#1] PREEMPT SMP
(...)
[61666.786253] task: ffff880117b88c40 task.stack: ffffc90008168000
[61666.786253] RIP: 0010:btrfs_set_item_key_safe+0x7c/0xd2 [btrfs]
[61666.786253] RSP: 0018:ffffc9000816b958 EFLAGS: 00010246
[61666.786253] RAX: 0000000000000000 RBX: 000000000000000f RCX: 0000000000030000
[61666.786253] RDX: 0000000000000000 RSI: ffffc9000816ba4f RDI: ffffc9000816b937
[61666.786253] RBP: ffffc9000816b998 R08: ffff88011dae2428 R09: 0000000000001000
[61666.786253] R10: 0000160000000000 R11: 6db6db6db6db6db7 R12: ffff88011dae2418
[61666.786253] R13: ffffc9000816ba4f R14: ffff8801e10c4118 R15: ffff8801e715c000
[61666.786253] FS: 00007f6060a18700(0000) GS:ffff88023f5c0000(0000) knlGS:0000000000000000
[61666.786253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[61666.786253] CR2: 00007f6060a28000 CR3: 0000000213e69000 CR4: 00000000000006e0
[61666.786253] Call Trace:
[61666.786253] __btrfs_drop_extents+0x5e3/0xaad [btrfs]
[61666.786253] ? time_hardirqs_on+0x9/0x14
[61666.786253] btrfs_log_changed_extents+0x294/0x4e0 [btrfs]
[61666.786253] ? release_extent_buffer+0x38/0xb4 [btrfs]
[61666.786253] btrfs_log_inode+0xb6e/0xcdc [btrfs]
[61666.786253] ? lock_acquire+0x131/0x1c5
[61666.786253] ? btrfs_log_inode_parent+0xee/0x659 [btrfs]
[61666.786253] ? arch_local_irq_save+0x9/0xc
[61666.786253] ? btrfs_log_inode_parent+0x1f5/0x659 [btrfs]
[61666.786253] btrfs_log_inode_parent+0x223/0x659 [btrfs]
[61666.786253] ? arch_local_irq_save+0x9/0xc
[61666.786253] ? lockref_get_not_zero+0x2c/0x34
[61666.786253] ? rcu_read_unlock+0x3e/0x5d
[61666.786253] btrfs_log_dentry_safe+0x60/0x7b [btrfs]
[61666.786253] btrfs_sync_file+0x317/0x42c [btrfs]
[61666.786253] vfs_fsync_range+0x8c/0x9e
[61666.786253] SyS_msync+0x13c/0x1c9
[61666.786253] entry_SYSCALL_64_fastpath+0x18/0xad
A sample of a corrupt log tree leaf with overlapping extents I got from
running btrfs/072:
item 14 key (295 108 200704) itemoff 2599 itemsize 53
extent data disk bytenr 0 nr 0
extent data offset 0 nr 458752 ram 458752
item 15 key (295 108 659456) itemoff 2546 itemsize 53
extent data disk bytenr 4343541760 nr 770048
extent data offset 606208 nr 163840 ram 770048
item 16 key (295 108 663552) itemoff 2493 itemsize 53
extent data disk bytenr 4343541760 nr 770048
extent data offset 610304 nr 155648 ram 770048
item 17 key (295 108 819200) itemoff 2440 itemsize 53
extent data disk bytenr 4334788608 nr 4096
extent data offset 0 nr 4096 ram 4096
The file extent item at offset 659456 (item 15) ends at offset 823296
(659456 + 163840) while the next file extent item (item 16) starts at
offset 663552.
Another different problem that the race can trigger is a failure in the
assertions at tree-log.c:copy_items(), which expect that the first file
extent item key we found before releasing the path exists after we have
released path and that the last key we found before releasing the path
also exists after releasing the path:
$ cat -n fs/btrfs/tree-log.c
4080 if (need_find_last_extent) {
4081 /* btrfs_prev_leaf could return 1 without releasing the path */
4082 btrfs_release_path(src_path);
4083 ret = btrfs_search_slot(NULL, inode->root, &first_key,
4084 src_path, 0, 0);
4085 if (ret < 0)
4086 return ret;
4087 ASSERT(ret == 0);
(...)
4103 if (i >= btrfs_header_nritems(src_path->nodes[0])) {
4104 ret = btrfs_next_leaf(inode->root, src_path);
4105 if (ret < 0)
4106 return ret;
4107 ASSERT(ret == 0);
4108 src = src_path->nodes[0];
4109 i = 0;
4110 need_find_last_extent = true;
4111 }
(...)
The second assertion implicitly expects that the last key before the path
release still exists, because the surrounding while loop only stops after
we have found that key. When this assertion fails it produces a stack like
this:
[139590.037075] assertion failed: ret == 0, file: fs/btrfs/tree-log.c, line: 4107
[139590.037406] ------------[ cut here ]------------
[139590.037707] kernel BUG at fs/btrfs/ctree.h:3546!
[139590.038034] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
[139590.038340] CPU: 1 PID: 31841 Comm: fsstress Tainted: G W 5.0.0-btrfs-next-46 #1
(...)
[139590.039354] RIP: 0010:assfail.constprop.24+0x18/0x1a [btrfs]
(...)
[139590.040397] RSP: 0018:ffffa27f48f2b9b0 EFLAGS: 00010282
[139590.040730] RAX: 0000000000000041 RBX: ffff897c635d92c8 RCX: 0000000000000000
[139590.041105] RDX: 0000000000000000 RSI: ffff897d36a96868 RDI: ffff897d36a96868
[139590.041470] RBP: ffff897d1b9a0708 R08: 0000000000000000 R09: 0000000000000000
[139590.041815] R10: 0000000000000008 R11: 0000000000000000 R12: 0000000000000013
[139590.042159] R13: 0000000000000227 R14: ffff897cffcbba88 R15: 0000000000000001
[139590.042501] FS: 00007f2efc8dee80(0000) GS:ffff897d36a80000(0000) knlGS:0000000000000000
[139590.042847] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[139590.043199] CR2: 00007f8c064935e0 CR3: 0000000232252002 CR4: 00000000003606e0
[139590.043547] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[139590.043899] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[139590.044250] Call Trace:
[139590.044631] copy_items+0xa3f/0x1000 [btrfs]
[139590.045009] ? generic_bin_search.constprop.32+0x61/0x200 [btrfs]
[139590.045396] btrfs_log_inode+0x7b3/0xd70 [btrfs]
[139590.045773] btrfs_log_inode_parent+0x2b3/0xce0 [btrfs]
[139590.046143] ? do_raw_spin_unlock+0x49/0xc0
[139590.046510] btrfs_log_dentry_safe+0x4a/0x70 [btrfs]
[139590.046872] btrfs_sync_file+0x3b6/0x440 [btrfs]
[139590.047243] btrfs_file_write_iter+0x45b/0x5c0 [btrfs]
[139590.047592] __vfs_write+0x129/0x1c0
[139590.047932] vfs_write+0xc2/0x1b0
[139590.048270] ksys_write+0x55/0xc0
[139590.048608] do_syscall_64+0x60/0x1b0
[139590.048946] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[139590.049287] RIP: 0033:0x7f2efc4be190
(...)
[139590.050342] RSP: 002b:00007ffe743243a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[139590.050701] RAX: ffffffffffffffda RBX: 0000000000008d58 RCX: 00007f2efc4be190
[139590.051067] RDX: 0000000000008d58 RSI: 00005567eca0f370 RDI: 0000000000000003
[139590.051459] RBP: 0000000000000024 R08: 0000000000000003 R09: 0000000000008d60
[139590.051863] R10: 0000000000000078 R11: 0000000000000246 R12: 0000000000000003
[139590.052252] R13: 00000000003d3507 R14: 00005567eca0f370 R15: 0000000000000000
(...)
[139590.055128] ---[ end trace 193f35d0215cdeeb ]---
So fix this race between a full ranged fsync and writeback of adjacent
ranges by flushing all delalloc and waiting for all ordered extents to
complete before logging the inode. This is the simplest way to solve the
problem because currently the full fsync path does not deal with ranges
at all (it assumes a full range from 0 to LLONG_MAX) and it always needs
to look at adjacent ranges for hole detection. For use cases of ranged
fsyncs this can make a few fsyncs slower but on the other hand it can
make some following fsyncs to other ranges do less work or no need to do
anything at all. A full fsync is rare anyway and happens only once after
loading/creating an inode and once after less common operations such as a
shrinking truncate.
This is an issue that exists for a long time, and was often triggered by
generic/127, because it does mmap'ed writes and msync (which triggers a
ranged fsync). Adding support for the tree checker to detect overlapping
extents (next patch in the series) and trigger a WARN() when such cases
are found, and then calling btrfs_check_leaf_full() at the end of
btrfs_insert_file_extent() made the issue much easier to detect. Running
btrfs/072 with that change to the tree checker and making fsstress open
files always with O_SYNC made it much easier to trigger the issue (as
triggering it with generic/127 is very rare).
CC: stable@vger.kernel.org # 3.16+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 72bd2323ec upstream.
Currently when we fail to COW a path at btrfs_update_root() we end up
always aborting the transaction. However all the current callers of
btrfs_update_root() are able to deal with errors returned from it, many do
end up aborting the transaction themselves (directly or not, such as the
transaction commit path), other BUG_ON() or just gracefully cancel whatever
they were doing.
When syncing the fsync log, we call btrfs_update_root() through
tree-log.c:update_log_root(), and if it returns an -ENOSPC error, the log
sync code does not abort the transaction, instead it gracefully handles
the error and returns -EAGAIN to the fsync handler, so that it falls back
to a transaction commit. Any other error different from -ENOSPC, makes the
log sync code abort the transaction.
So remove the transaction abort from btrfs_update_log() when we fail to
COW a path to update the root item, so that if an -ENOSPC failure happens
we avoid aborting the current transaction and have a chance of the fsync
succeeding after falling back to a transaction commit.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203413
Fixes: 79787eaab4 ("btrfs: replace many BUG_ONs with proper error handling")
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5a5ec83d6a upstream.
Commit 4d207133e9 changed the types of the statistic values in struct
gfs2_lkstats from s64 to u64. Because of that, what should be a signed
value in gfs2_update_stats turned into an unsigned value. When shifted
right, we end up with a large positive value instead of a small negative
value, which results in an incorrect variance estimate.
Fixes: 4d207133e9 ("gfs2: Make statistics unsigned, suitable for use with do_div()")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: stable@vger.kernel.org # v4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ee0ed02ca9 upstream.
It is possible that unlinked inode enters ext4_setattr() (e.g. if
somebody calls ftruncate(2) on unlinked but still open file). In such
case we should not delete the inode from the orphan list if truncate
fails. Note that this is mostly a theoretical concern as filesystem is
corrupted if we reach this path anyway but let's be consistent in our
orphan handling.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c2d1b3aae3 upstream.
Up until now trimming the freespace was done irrespective of what the
arguments of the FITRIM ioctl were. For example fstrim's -o/-l arguments
will be entirely ignored. Fix it by correctly handling those paramter.
This requires breaking if the found freespace extent is after the end of
the passed range as well as completing trim after trimming
fstrim_range::len bytes.
Fixes: 499f377f49 ("btrfs: iterate over unused chunk space in FITRIM")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Nikolay Borisov <nborisov@suse.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>
[ Upstream commit 4e9036042f ]
To choose whether to pick the GID from the old (16bit) or new (32bit)
field, we should check if the old gid field is set to 0xffff. Mainline
checks the old *UID* field instead - cut'n'paste from the corresponding
code in ufs_get_inode_uid().
Fixes: 252e211e90
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
