Kirill A Shutemov reports that the kernel doesn't try to cap dest_count
in any way, and uses the number to allocate kernel memory. This causes
high order allocation warnings in the kernel log if someone passes in a
big enough value. We should clamp the allocation at PAGE_SIZE to avoid
stressing the VM.
The two existing users of the dedupe ioctl never send more than 120
requests, so we can safely clamp dest_range at PAGE_SIZE, because with
4k pages we can handle up to 127 dedupe candidates. Given the max
extent length of 16MB, we can end up doing 2GB of IO which is plenty.
[ Note: the "offsetof()" can't overflow, because 'count' is just a
16-bit integer. That's not obvious in the limited context of the
patch, so I'm noting it here because it made me go look. - Linus ]
Reported-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All the VFS functions in the dedupe ioctl path return int status, so
the ioctl handler ought to as well.
Found by Coverity, CID 1350952.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This prevents a double-fetch from user space that can lead to to an
undersized allocation and heap overflow.
Fixes: 54dbc15172 ("vfs: hoist the btrfs deduplication ioctl to the vfs")
Signed-off-by: Scott Bauer <sbauer@plzdonthack.me>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).
Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull vfs copy_file_range updates from Al Viro:
"Several series around copy_file_range/CLONE"
* 'work.copy_file_range' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
btrfs: use new dedupe data function pointer
vfs: hoist the btrfs deduplication ioctl to the vfs
vfs: wire up compat ioctl for CLONE/CLONE_RANGE
cifs: avoid unused variable and label
nfsd: implement the NFSv4.2 CLONE operation
nfsd: Pass filehandle to nfs4_preprocess_stateid_op()
vfs: pull btrfs clone API to vfs layer
locks: new locks_mandatory_area calling convention
vfs: Add vfs_copy_file_range() support for pagecache copies
btrfs: add .copy_file_range file operation
x86: add sys_copy_file_range to syscall tables
vfs: add copy_file_range syscall and vfs helper
Hoist the btrfs EXTENT_SAME ioctl up to the VFS and make the name
more systematic (FIDEDUPERANGE).
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The btrfs clone ioctls are now adopted by other file systems, with NFS
and CIFS already having support for them, and XFS being under active
development. To avoid growth of various slightly incompatible
implementations, add one to the VFS. Note that clones are different from
file copies in several ways:
- they are atomic vs other writers
- they support whole file clones
- they support 64-bit legth clones
- they do not allow partial success (aka short writes)
- clones are expected to be a fast metadata operation
Because of that it would be rather cumbersome to try to piggyback them on
top of the recent clone_file_range infrastructure. The converse isn't
true and the clone_file_range system call could try clone file range as
a first attempt to copy, something that further patches will enable.
Based on earlier work from Peng Tao.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
__generic_block_fiemap may spin very long time for large sparse files.
Without this patch an unprivileged user may abuse system resources simply
by spawning a vast number of unkilable busyloops (works on ext2/ext3):
truncate --size 1T test
for ((i=0;i<1024;i++))
do
filefrag test > /dev/null &
done
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull nfsd updates from Bruce Fields:
"A comparatively quieter cycle for nfsd this time, but still with two
larger changes:
- RPC server scalability improvements from Jeff Layton (using RCU
instead of a spinlock to find idle threads).
- server-side NFSv4.2 ALLOCATE/DEALLOCATE support from Anna
Schumaker, enabling fallocate on new clients"
* 'for-3.19' of git://linux-nfs.org/~bfields/linux: (32 commits)
nfsd4: fix xdr4 count of server in fs_location4
nfsd4: fix xdr4 inclusion of escaped char
sunrpc/cache: convert to use string_escape_str()
sunrpc: only call test_bit once in svc_xprt_received
fs: nfsd: Fix signedness bug in compare_blob
sunrpc: add some tracepoints around enqueue and dequeue of svc_xprt
sunrpc: convert to lockless lookup of queued server threads
sunrpc: fix potential races in pool_stats collection
sunrpc: add a rcu_head to svc_rqst and use kfree_rcu to free it
sunrpc: require svc_create callers to pass in meaningful shutdown routine
sunrpc: have svc_wake_up only deal with pool 0
sunrpc: convert sp_task_pending flag to use atomic bitops
sunrpc: move rq_cachetype field to better optimize space
sunrpc: move rq_splice_ok flag into rq_flags
sunrpc: move rq_dropme flag into rq_flags
sunrpc: move rq_usedeferral flag to rq_flags
sunrpc: move rq_local field to rq_flags
sunrpc: add a generic rq_flags field to svc_rqst and move rq_secure to it
nfsd: minor off by one checks in __write_versions()
sunrpc: release svc_pool_map reference when serv allocation fails
...
Currently, freezing a filesystem involves calling freeze_super, which locks
sb->s_umount and then calls the fs-specific freeze_fs hook. This makes it
hard for gfs2 (and potentially other cluster filesystems) to use the vfs
freezing code to do freezes on all the cluster nodes.
In order to communicate that a freeze has been requested, and to make sure
that only one node is trying to freeze at a time, gfs2 uses a glock
(sd_freeze_gl). The problem is that there is no hook for gfs2 to acquire
this lock before calling freeze_super. This means that two nodes can
attempt to freeze the filesystem by both calling freeze_super, acquiring
the sb->s_umount lock, and then attempting to grab the cluster glock
sd_freeze_gl. Only one will succeed, and the other will be stuck in
freeze_super, making it impossible to finish freezing the node.
To solve this problem, this patch adds the freeze_super and thaw_super
hooks. If a filesystem implements these hooks, they are called instead of
the vfs freeze_super and thaw_super functions. This means that every
filesystem that implements these hooks must call the vfs freeze_super and
thaw_super functions itself within the hook function to make use of the vfs
freezing code.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This function needs to be exported so it can be used by the NFSD module
when responding to the new ALLOCATE and DEALLOCATE operations in NFS
v4.2. Christoph Hellwig suggested renaming the function to stay
consistent with how other vfs functions are named.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include. Fix up any implicit
include dependencies that were being masked by module.h along
the way.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
We're doing some odd things there, which already messes up various users
(see the net/socket.c code that this removes), and it was going to add
yet more crud to the block layer because of the incorrect error code
translation.
ENOIOCTLCMD is not an error return that should be returned to user mode
from the "ioctl()" system call, but it should *not* be translated as
EINVAL ("Invalid argument"). It should be translated as ENOTTY
("Inappropriate ioctl for device").
That EINVAL confusion has apparently so permeated some code that the
block layer actually checks for it, which is sad. We continue to do so
for now, but add a big comment about how wrong that is, and we should
remove it entirely eventually. In the meantime, this tries to keep the
changes localized to just the EINVAL -> ENOTTY fix, and removing code
that makes it harder to do the right thing.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move declaration of 'inode' to beginning of the function. Since it
is referenced directly or indirectly (in case of FIFREEZE/FITHAW/
FS_IOC_FIEMAP) it's not harmful IMHO. And remove unnecessary casts
using 'argp' instead.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Some filesystems don't deal well with being asked to map less than
blocksize blocks (GFS2 for example). Since we are always mapping at least
blocksize sections anyway, just make sure len is at least as big as a
blocksize so we don't trip up any filesystems. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The fi_extents_start field of struct fiemap_extent_info is a
user pointer but was not marked as __user. This makes sparse
emit following warnings:
CHECK fs/ioctl.c
fs/ioctl.c:114:26: warning: incorrect type in argument 1 (different address spaces)
fs/ioctl.c:114:26: expected void [noderef] <asn:1>*dst
fs/ioctl.c:114:26: got struct fiemap_extent *[assigned] dest
fs/ioctl.c:202:14: warning: incorrect type in argument 1 (different address spaces)
fs/ioctl.c:202:14: expected void const volatile [noderef] <asn:1>*<noident>
fs/ioctl.c:202:14: got struct fiemap_extent *[assigned] fi_extents_start
fs/ioctl.c:212:27: warning: incorrect type in argument 1 (different address spaces)
fs/ioctl.c:212:27: expected void [noderef] <asn:1>*dst
fs/ioctl.c:212:27: got char *<noident>
Also add 'ufiemap' variable to eliminate unnecessary casts.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Add EXT4_IOC_TRIM ioctl to handle batched discard
fs: Do not dispatch FITRIM through separate super_operation
ext4: ext4_fill_super shouldn't return 0 on corruption
jbd2: fix /proc/fs/jbd2/<dev> when using an external journal
ext4: missing unlock in ext4_clear_request_list()
ext4: fix setting random pages PageUptodate
There was concern that FITRIM ioctl is not common enough to be included
in core vfs ioctl, as Christoph Hellwig pointed out there's no real point
in dispatching this out to a separate vector instead of just through
->ioctl.
So this commit removes ioctl_fstrim() from vfs ioctl and trim_fs
from super_operation structure.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.
Remove this too as a cleanup.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Adds an filesystem independent ioctl to allow implementation of file
system batched discard support. I takes fstrim_range structure as an
argument. fstrim_range is definec in the include/fs.h and its
definition is as follows.
struct fstrim_range {
start;
len;
minlen;
}
start - first Byte to trim
len - number of Bytes to trim from start
minlen - minimum extent length to trim, free extents shorter than this
number of Bytes will be ignored. This will be rounded up to fs
block size.
It is also possible to specify NULL as an argument. In this case the
arguments will set itself as follows:
start = 0;
len = ULLONG_MAX;
minlen = 0;
So it will trim the whole file system at one run.
After the FITRIM is done, the number of actually discarded Bytes is stored
in fstrim_range.len to give the user better insight on how much storage
space has been really released for wear-leveling.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Darrick J. Wong
Scott Bauer
Al Viro
Linus Torvalds
Christoph Hellwig
Dmitry Monakhov
Benjamin Marzinski
Anna Schumaker
Paul Gortmaker
Namhyung Kim
Josef Bacik
Lukas Czerner
Arnd Bergmann