The ext4 fstrim implementation uses the block bitmaps to find free space
that can be discarded.  If we haven't replayed the journal, the bitmaps
will be stale and we absolutely *cannot* use stale metadata to zap the
underlying storage.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Currently, we are releasing the indirect buffer where we are done with
it in ext4_ind_remove_space(), so we can see the brelse() and
BUFFER_TRACE() everywhere.  It seems fragile and hard to read, and we
may probably forget to release the buffer some day.  This patch cleans
up the code by putting of the code which releases the buffers to the
end of the function.
Signed-off-by: Nzhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>

All indirect buffers get by ext4_find_shared() should be released no
mater the branch should be freed or not. But now, we forget to release
the lower depth indirect buffers when removing space from the same
higher depth indirect block. It will lead to buffer leak and futher
more, it may lead to quota information corruption when using old quota,
consider the following case.

 - Create and mount an empty ext4 filesystem without extent and quota
   features,
 - quotacheck and enable the user & group quota,
 - Create some files and write some data to them, and then punch hole
   to some files of them, it may trigger the buffer leak problem
   mentioned above.
 - Disable quota and run quotacheck again, it will create two new
   aquota files and write the checked quota information to them, which
   probably may reuse the freed indirect block(the buffer and page
   cache was not freed) as data block.
 - Enable quota again, it will invoke
   vfs_load_quota_inode()->invalidate_bdev() to try to clean unused
   buffers and pagecache. Unfortunately, because of the buffer of quota
   data block is still referenced, quota code cannot read the up to date
   quota info from the device and lead to quota information corruption.

This problem can be reproduced by xfstests generic/231 on ext3 file
system or ext4 file system without extent and quota features.

This patch fix this problem by releasing the missing indirect buffers,
in ext4_ind_remove_space().
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: Nzhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: stable@kernel.org

On machines where the GART aperture is mapped over physical RAM,
/proc/kcore contains the GART aperture range. Accessing the GART range via
/proc/kcore results in a kernel crash.

vmcore used to have the same issue, until it was fixed with commit
2a3e83c6 ("x86/gart: Exclude GART aperture from vmcore")', leveraging
existing hook infrastructure in vmcore to let /proc/vmcore return zeroes
when attempting to read the aperture region, and so it won't read from the
actual memory.

Apply the same workaround for kcore. First implement the same hook
infrastructure for kcore, then reuse the hook functions introduced in the
previous vmcore fix. Just with some minor adjustment, rename some functions
for more general usage, and simplify the hook infrastructure a bit as there
is no module usage yet.
Suggested-by: NBaoquan He <bhe@redhat.com>
Signed-off-by: NKairui Song <kasong@redhat.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NJiri Bohac <jbohac@suse.cz>
Acked-by: NBaoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Dave Young <dyoung@redhat.com>
Link: https://lkml.kernel.org/r/20190308030508.13548-1-kasong@redhat.com

To 2.19
Signed-off-by: NSteve French <stfrench@microsoft.com>

Workaround problem with Samba responses to SMB3.1.1
null user (guest) mounts.  The server doesn't set the
expected flag in the session setup response so we have
to do a similar check to what is done in smb3_validate_negotiate
where we also check if the user is a null user (but not sec=krb5
since username might not be passed in on mount for Kerberos case).

Note that the commit below tightened the conditions and forced signing
for the SMB2-TreeConnect commands as per MS-SMB2.
However, this should only apply to normal user sessions and not for
cases where there is no user (even if server forgets to set the flag
in the response) since we don't have anything useful to sign with.
This is especially important now that the more secure SMB3.1.1 protocol
is in the default dialect list.

An earlier patch ("cifs: allow guest mounts to work for smb3.11") fixed
the guest mounts to Windows.

    Fixes: 6188f28b ("Tree connect for SMB3.1.1 must be signed for non-encrypted shares")
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: NPaulo Alcantara <palcantara@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <stfrench@microsoft.com>

This patch fixes the following KASAN report:

[  779.044746] BUG: KASAN: slab-out-of-bounds in string+0xab/0x180
[  779.044750] Read of size 1 at addr ffff88814f327968 by task trace-cmd/2812

[  779.044756] CPU: 1 PID: 2812 Comm: trace-cmd Not tainted 5.1.0-rc1+ #62
[  779.044760] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-0-ga698c89-prebuilt.qemu.org 04/01/2014
[  779.044761] Call Trace:
[  779.044769]  dump_stack+0x5b/0x90
[  779.044775]  ? string+0xab/0x180
[  779.044781]  print_address_description+0x6c/0x23c
[  779.044787]  ? string+0xab/0x180
[  779.044792]  ? string+0xab/0x180
[  779.044797]  kasan_report.cold.3+0x1a/0x32
[  779.044803]  ? string+0xab/0x180
[  779.044809]  string+0xab/0x180
[  779.044816]  ? widen_string+0x160/0x160
[  779.044822]  ? vsnprintf+0x5bf/0x7f0
[  779.044829]  vsnprintf+0x4e7/0x7f0
[  779.044836]  ? pointer+0x4a0/0x4a0
[  779.044841]  ? seq_buf_vprintf+0x79/0xc0
[  779.044848]  seq_buf_vprintf+0x62/0xc0
[  779.044855]  trace_seq_printf+0x113/0x210
[  779.044861]  ? trace_seq_puts+0x110/0x110
[  779.044867]  ? trace_raw_output_prep+0xd8/0x110
[  779.044876]  trace_raw_output_smb3_tcon_class+0x9f/0xc0
[  779.044882]  print_trace_line+0x377/0x890
[  779.044888]  ? tracing_buffers_read+0x300/0x300
[  779.044893]  ? ring_buffer_read+0x58/0x70
[  779.044899]  s_show+0x6e/0x140
[  779.044906]  seq_read+0x505/0x6a0
[  779.044913]  vfs_read+0xaf/0x1b0
[  779.044919]  ksys_read+0xa1/0x130
[  779.044925]  ? kernel_write+0xa0/0xa0
[  779.044931]  ? __do_page_fault+0x3d5/0x620
[  779.044938]  do_syscall_64+0x63/0x150
[  779.044944]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  779.044949] RIP: 0033:0x7f62c2c2db31
[ 779.044955] Code: fe ff ff 48 8d 3d 17 9e 09 00 48 83 ec 08 e8 96 02
02 00 66 0f 1f 44 00 00 8b 05 fa fc 2c 00 48 63 ff 85 c0 75 13 31 c0
0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48
89
[  779.044958] RSP: 002b:00007ffd6e116678 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[  779.044964] RAX: ffffffffffffffda RBX: 0000560a38be9260 RCX: 00007f62c2c2db31
[  779.044966] RDX: 0000000000002000 RSI: 00007ffd6e116710 RDI: 0000000000000003
[  779.044966] RDX: 0000000000002000 RSI: 00007ffd6e116710 RDI: 0000000000000003
[  779.044969] RBP: 00007f62c2ef5420 R08: 0000000000000000 R09: 0000000000000003
[  779.044972] R10: ffffffffffffffa8 R11: 0000000000000246 R12: 00007ffd6e116710
[  779.044975] R13: 0000000000002000 R14: 0000000000000d68 R15: 0000000000002000

[  779.044981] Allocated by task 1257:
[  779.044987]  __kasan_kmalloc.constprop.5+0xc1/0xd0
[  779.044992]  kmem_cache_alloc+0xad/0x1a0
[  779.044997]  getname_flags+0x6c/0x2a0
[  779.045003]  user_path_at_empty+0x1d/0x40
[  779.045008]  do_faccessat+0x12a/0x330
[  779.045012]  do_syscall_64+0x63/0x150
[  779.045017]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[  779.045019] Freed by task 1257:
[  779.045023]  __kasan_slab_free+0x12e/0x180
[  779.045029]  kmem_cache_free+0x85/0x1b0
[  779.045034]  filename_lookup.part.70+0x176/0x250
[  779.045039]  do_faccessat+0x12a/0x330
[  779.045043]  do_syscall_64+0x63/0x150
[  779.045048]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[  779.045052] The buggy address belongs to the object at ffff88814f326600
which belongs to the cache names_cache of size 4096
[  779.045057] The buggy address is located 872 bytes to the right of
4096-byte region [ffff88814f326600, ffff88814f327600)
[  779.045058] The buggy address belongs to the page:
[  779.045062] page:ffffea00053cc800 count:1 mapcount:0 mapping:ffff88815b191b40 index:0x0 compound_mapcount: 0
[  779.045067] flags: 0x200000000010200(slab|head)
[  779.045075] raw: 0200000000010200 dead000000000100 dead000000000200 ffff88815b191b40
[  779.045081] raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
[  779.045083] page dumped because: kasan: bad access detected

[  779.045085] Memory state around the buggy address:
[  779.045089]  ffff88814f327800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045093]  ffff88814f327880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045097] >ffff88814f327900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045099]                                                           ^
[  779.045103]  ffff88814f327980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045107]  ffff88814f327a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045109] ==================================================================
[  779.045110] Disabling lock debugging due to kernel taint

Correctly assign tree name str for smb3_tcon event.
Signed-off-by: NPaulo Alcantara (SUSE) <paulo@paulo.ac>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Fix Guest/Anonymous sessions so that they work with SMB 3.11.

The commit noted below tightened the conditions and forced signing for
the SMB2-TreeConnect commands as per MS-SMB2.
However, this should only apply to normal user sessions and not for
Guest/Anonumous sessions.

Fixes: 6188f28b ("Tree connect for SMB3.1.1 must be signed for non-encrypted shares")
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <stfrench@microsoft.com>

It was mapped to EIO which can be confusing when user space
queries for an object GUID for an object for which the server
file system doesn't support (or hasn't saved one).

As Amir Goldstein suggested this is similar to ENOATTR
(equivalently ENODATA in Linux errno definitions) so
changing NT STATUS code mapping for OBJECTID_NOT_FOUND
to ENODATA.
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Amir Goldstein <amir73il@gmail.com>

dedupe_file_range operations is combiled into remap_file_range.
But it's always skipped for dedupe operations in function
cifs_remap_file_range.

Example to test:
Before this patch:
  # dd if=/dev/zero of=cifs/file bs=1M count=1
  # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file
  XFS_IOC_FILE_EXTENT_SAME: Invalid argument

After this patch:
  # dd if=/dev/zero of=cifs/file bs=1M count=1
  # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file
  XFS_IOC_FILE_EXTENT_SAME: Operation not supported

Influence for xfstests:
generic/091
generic/112
generic/127
generic/263
These tests report this error "do_copy_range:: Invalid
argument" instead of "FIDEDUPERANGE: Invalid argument".
Because there are still two bugs cause these test failed.
https://bugzilla.kernel.org/show_bug.cgi?id=202935
https://bugzilla.kernel.org/show_bug.cgi?id=202785Signed-off-by: NXiaoli Feng <fengxiaoli0714@gmail.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

When sending a rdata, transport may return -EAGAIN. In this case
we should re-obtain credits because the session may have been
reconnected.

Change in v2: adjust_credits before re-sending
Signed-off-by: NLong Li <longli@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

When sending a wdata, transport may return -EAGAIN. In this case
we should re-obtain credits because the session may have been
reconnected.

Change in v2: adjust_credits before re-sending
Signed-off-by: NLong Li <longli@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

When file handle is embedded inside fanotify_event and usercopy checks
are enabled, we get a warning like:

Bad or missing usercopy whitelist? Kernel memory exposure attempt detected
from SLAB object 'fanotify_event' (offset 40, size 8)!
WARNING: CPU: 1 PID: 7649 at mm/usercopy.c:78 usercopy_warn+0xeb/0x110
mm/usercopy.c:78

Annotate handling in fanotify_event properly to mark copying it to
userspace is fine.

Reported-by: syzbot+2c49971e251e36216d1f@syzkaller.appspotmail.com
Fixes: a8b13aa2 ("fanotify: enable FAN_REPORT_FID init flag")
Signed-off-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NAmir Goldstein <amir73il@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

If bio_iov_iter_get_pages() is called on an iov_iter that is flagged
with NO_REF, then we don't need to add a page reference for the pages
that we add.

Add BIO_NO_PAGE_REF to track this in the bio, so IO completion knows
not to drop a reference to these pages.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

For ITER_BVEC, if we're holding on to kernel pages, the caller
doesn't need to grab a reference to the bvec pages, and drop that
same reference on IO completion. This is essentially safe for any
ITER_BVEC, but some use cases end up reusing pages and uncondtionally
dropping a page reference on completion. And example of that is
sendfile(2), that ends up being a splice_in + splice_out on the
pipe pages.

Add a flag that tells us it's fine to not grab a page reference
to the bvec pages, since that caller knows not to drop a reference
when it's done with the pages.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

I've seen cases where bulk alloc fails, since the bulk alloc API
is all-or-nothing - either we get the number we ask for, or it
returns 0 as number of entries.

If we fail a batch bulk alloc, retry a "normal" kmem_cache_alloc()
and just use that instead of failing with -EAGAIN.

While in there, ensure we use GFP_KERNEL. That was an oversight in
the original code, when we switched away from GFP_ATOMIC.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Make udf_truncate_extents() properly propagate errors to its callers and
let udf_setsize() handle the error properly as well. This lets userspace
know in case there's some error when truncating blocks.
Signed-off-by: NJan Kara <jack@suse.cz>

When truncate(2) hits IO error when reading indirect extent block the
code just bugs with:

kernel BUG at linux-4.15.0/fs/udf/truncate.c:249!
...

Fix the problem by bailing out cleanly in case of IO error.

CC: stable@vger.kernel.org
Reported-by: Njean-luc malet <jeanluc.malet@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Permission checks on current's netns should be done only when
netns are enabled.
Reported-by: NDominik Brodowski <linux@dominikbrodowski.net>
Fixes: 23bf1b6bSigned-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This is a straight port of Al's fix for the aio poll implementation,
since the io_uring version is heavily based on that. The below
description is almost straight from that patch, just modified to
fit the io_uring situation.

io_poll() has to cope with several unpleasant problems:
	* requests that might stay around indefinitely need to
be made visible for io_cancel(2); that must not be done to
a request already completed, though.
	* in cases when ->poll() has placed us on a waitqueue,
wakeup might have happened (and request completed) before ->poll()
returns.
	* worse, in some early wakeup cases request might end
up re-added into the queue later - we can't treat "woken up and
currently not in the queue" as "it's not going to stick around
indefinitely"
	* ... moreover, ->poll() might have decided not to
put it on any queues to start with, and that needs to be distinguished
from the previous case
	* ->poll() might have tried to put us on more than one queue.
Only the first will succeed for io poll, so we might end up missing
wakeups.  OTOH, we might very well notice that only after the
wakeup hits and request gets completed (all before ->poll() gets
around to the second poll_wait()).  In that case it's too late to
decide that we have an error.

req->woken was an attempt to deal with that.  Unfortunately, it was
broken.  What we need to keep track of is not that wakeup has happened -
the thing might come back after that.  It's that async reference is
already gone and won't come back, so we can't (and needn't) put the
request on the list of cancellables.

The easiest case is "request hadn't been put on any waitqueues"; we
can tell by seeing NULL apt.head, and in that case there won't be
anything async.  We should either complete the request ourselves
(if vfs_poll() reports anything of interest) or return an error.

In all other cases we get exclusion with wakeups by grabbing the
queue lock.

If request is currently on queue and we have something interesting
from vfs_poll(), we can steal it and complete the request ourselves.

If it's on queue and vfs_poll() has not reported anything interesting,
we either put it on the cancellable list, or, if we know that it
hadn't been put on all queues ->poll() wanted it on, we steal it and
return an error.

If it's _not_ on queue, it's either been already dealt with (in which
case we do nothing), or there's io_poll_complete_work() about to be
executed.  In that case we either put it on the cancellable list,
or, if we know it hadn't been put on all queues ->poll() wanted it on,
simulate what cancel would've done.

Fixes: 221c5eb2 ("io_uring: add support for IORING_OP_POLL")
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This isn't a straight port of commit 84c4e1f8 for aio.c, since
io_uring doesn't use files in exactly the same way. But it's pretty
close. See the commit message for that commit.

This essentially fixes a use-after-free with the poll command
handling, but it takes cue from Linus's approach to just simplifying
the file handling. We move the setup of the file into a higher level
location, so the individual commands don't have to deal with it. And
then we release the reference when we free the associated io_kiocb.

Fixes: 221c5eb2 ("io_uring: add support for IORING_OP_POLL")
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We currently use the fact that if ->ki_filp is already set, then we've
done the prep. In preparation for moving the file assignment earlier,
use a separate flag to tell whether the request has been prepped for
IO or not.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The callers all convert to an integer, and we only return 0/-ERROR
anyway.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Currently when the file system resize using ext4_resize_fs() fails it
will report into log that "resized filesystem to <requested block
count>".  However this may not be true in the case of failure.  Use the
current block count as returned by ext4_blocks_count() to report the
block count.

Additionally, report a warning that "error occurred during file system
resize"
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Currently in add_new_gdb_meta_bg() there is a missing brelse of gdb_bh
in case ext4_journal_get_write_access() fails.
Additionally kvfree() is missing in the same error path. Fix it by
moving the ext4_journal_get_write_access() before the ext4 sb update as
Ted suggested and release n_group_desc and gdb_bh in case it fails.

Fixes: 61a9c11e ("ext4: add missing brelse() add_new_gdb_meta_bg()'s error path")
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Get rid of the special casing of "normal" requests not having
any references to the io_kiocb. We initialize the ref count to 2,
one for the submission side, and one or the completion side.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This function is never used from the beginning (and is commented out);
let's remove it.
Signed-off-by: NJason Yan <yanaijie@huawei.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

When admin calls "reboot -f" - i.e., does a hard system reboot by
directly calling reboot(2) - ext4 filesystem mounted with errors=panic
can panic the system. This happens because the underlying device gets
disabled without unmounting the filesystem and thus some syscall running
in parallel to reboot(2) can result in the filesystem getting IO errors.

This is somewhat surprising to the users so try improve the behavior by
switching to errors=remount-ro behavior when the system is running
reboot(2).
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Ext4 needs to serialize unaligned direct AIO because the zeroing of
partial blocks of two competing unaligned AIOs can result in data
corruption.

However it decides not to serialize if the potentially unaligned aio is
past i_size with the rationale that no pending writes are possible past
i_size. Unfortunately if the i_size is not block aligned and the second
unaligned write lands past i_size, but still into the same block, it has
the potential of corrupting the previous unaligned write to the same
block.

This is (very simplified) reproducer from Frank

    // 41472 = (10 * 4096) + 512
    // 37376 = 41472 - 4096

    ftruncate(fd, 41472);
    io_prep_pwrite(iocbs[0], fd, buf[0], 4096, 37376);
    io_prep_pwrite(iocbs[1], fd, buf[1], 4096, 41472);

    io_submit(io_ctx, 1, &iocbs[1]);
    io_submit(io_ctx, 1, &iocbs[2]);

    io_getevents(io_ctx, 2, 2, events, NULL);

Without this patch the 512B range from 40960 up to the start of the
second unaligned write (41472) is going to be zeroed overwriting the data
written by the first write. This is a data corruption.

00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
*
00009200  30 30 30 30 30 30 30 30  30 30 30 30 30 30 30 30
*
0000a000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
*
0000a200  31 31 31 31 31 31 31 31  31 31 31 31 31 31 31 31

With this patch the data corruption is avoided because we will recognize
the unaligned_aio and wait for the unwritten extent conversion.

00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
*
00009200  30 30 30 30 30 30 30 30  30 30 30 30 30 30 30 30
*
0000a200  31 31 31 31 31 31 31 31  31 31 31 31 31 31 31 31
*
0000b200
Reported-by: NFrank Sorenson <fsorenso@redhat.com>
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Fixes: e9e3bcec ("ext4: serialize unaligned asynchronous DIO")
Cc: stable@vger.kernel.org

We see the following NULL pointer dereference while running xfstests
generic/475:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
PGD 8000000c84bad067 P4D 8000000c84bad067 PUD c84e62067 PMD 0
Oops: 0000 [#1] SMP PTI
CPU: 7 PID: 9886 Comm: fsstress Kdump: loaded Not tainted 5.0.0-rc8 #10
RIP: 0010:ext4_do_update_inode+0x4ec/0x760
...
Call Trace:
? jbd2_journal_get_write_access+0x42/0x50
? __ext4_journal_get_write_access+0x2c/0x70
? ext4_truncate+0x186/0x3f0
ext4_mark_iloc_dirty+0x61/0x80
ext4_mark_inode_dirty+0x62/0x1b0
ext4_truncate+0x186/0x3f0
? unmap_mapping_pages+0x56/0x100
ext4_setattr+0x817/0x8b0
notify_change+0x1df/0x430
do_truncate+0x5e/0x90
? generic_permission+0x12b/0x1a0

This is triggered because the NULL pointer handle->h_transaction was
dereferenced in function ext4_update_inode_fsync_trans().
I found that the h_transaction was set to NULL in jbd2__journal_restart
but failed to attached to a new transaction while the journal is aborted.

Fix this by checking the handle before updating the inode.

Fixes: b436b9be ("ext4: Wait for proper transaction commit on fsync")
Signed-off-by: NJiufei Xue <jiufei.xue@linux.alibaba.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Cc: stable@kernel.org

We have a customer reporting crashes in lock_get_status() with many
"Leaked POSIX lock" messages preceeding the crash.

 Leaked POSIX lock on dev=0x0:0x56 ...
 Leaked POSIX lock on dev=0x0:0x56 ...
 Leaked POSIX lock on dev=0x0:0x56 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 POSIX: fl_owner=ffff8900e7b79380 fl_flags=0x1 fl_type=0x1 fl_pid=20709
 Leaked POSIX lock on dev=0x0:0x4b ino...
 Leaked locks on dev=0x0:0x4b ino=0xf911400000029:
 POSIX: fl_owner=ffff89f41c870e00 fl_flags=0x1 fl_type=0x1 fl_pid=19592
 stack segment: 0000 [#1] SMP
 Modules linked in: binfmt_misc msr tcp_diag udp_diag inet_diag unix_diag af_packet_diag netlink_diag rpcsec_gss_krb5 arc4 ecb auth_rpcgss nfsv4 md4 nfs nls_utf8 lockd grace cifs sunrpc ccm dns_resolver fscache af_packet iscsi_ibft iscsi_boot_sysfs vmw_vsock_vmci_transport vsock xfs libcrc32c sb_edac edac_core crct10dif_pclmul crc32_pclmul ghash_clmulni_intel drbg ansi_cprng vmw_balloon aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd joydev pcspkr vmxnet3 i2c_piix4 vmw_vmci shpchp fjes processor button ac btrfs xor raid6_pq sr_mod cdrom ata_generic sd_mod ata_piix vmwgfx crc32c_intel drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm serio_raw ahci libahci drm libata vmw_pvscsi sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_mod autofs4

 Supported: Yes
 CPU: 6 PID: 28250 Comm: lsof Not tainted 4.4.156-94.64-default #1
 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/05/2016
 task: ffff88a345f28740 ti: ffff88c74005c000 task.ti: ffff88c74005c000
 RIP: 0010:[<ffffffff8125dcab>]  [<ffffffff8125dcab>] lock_get_status+0x9b/0x3b0
 RSP: 0018:ffff88c74005fd90  EFLAGS: 00010202
 RAX: ffff89bde83e20ae RBX: ffff89e870003d18 RCX: 0000000049534f50
 RDX: ffffffff81a3541f RSI: ffffffff81a3544e RDI: ffff89bde83e20ae
 RBP: 0026252423222120 R08: 0000000020584953 R09: 000000000000ffff
 R10: 0000000000000000 R11: ffff88c74005fc70 R12: ffff89e5ca7b1340
 R13: 00000000000050e5 R14: ffff89e870003d30 R15: ffff89e5ca7b1340
 FS:  00007fafd64be800(0000) GS:ffff89f41fd00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000001c80018 CR3: 000000a522048000 CR4: 0000000000360670
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Stack:
  0000000000000208 ffffffff81a3d6b6 ffff89e870003d30 ffff89e870003d18
  ffff89e5ca7b1340 ffff89f41738d7c0 ffff89e870003d30 ffff89e5ca7b1340
  ffffffff8125e08f 0000000000000000 ffff89bc22b67d00 ffff88c74005ff28
 Call Trace:
  [<ffffffff8125e08f>] locks_show+0x2f/0x70
  [<ffffffff81230ad1>] seq_read+0x251/0x3a0
  [<ffffffff81275bbc>] proc_reg_read+0x3c/0x70
  [<ffffffff8120e456>] __vfs_read+0x26/0x140
  [<ffffffff8120e9da>] vfs_read+0x7a/0x120
  [<ffffffff8120faf2>] SyS_read+0x42/0xa0
  [<ffffffff8161cbc3>] entry_SYSCALL_64_fastpath+0x1e/0xb7

When Linux closes a FD (close(), close-on-exec, dup2(), ...) it calls
filp_close() which also removes all posix locks.

The lock struct is initialized like so in filp_close() and passed
down to cifs

	...
        lock.fl_type = F_UNLCK;
        lock.fl_flags = FL_POSIX | FL_CLOSE;
        lock.fl_start = 0;
        lock.fl_end = OFFSET_MAX;
	...

Note the FL_CLOSE flag, which hints the VFS code that this unlocking
is done for closing the fd.

filp_close()
  locks_remove_posix(filp, id);
    vfs_lock_file(filp, F_SETLK, &lock, NULL);
      return filp->f_op->lock(filp, cmd, fl) => cifs_lock()
        rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock, xid);
          rc = server->ops->mand_unlock_range(cfile, flock, xid);
          if (flock->fl_flags & FL_POSIX && !rc)
                  rc = locks_lock_file_wait(file, flock)

Notice how we don't call locks_lock_file_wait() which does the
generic VFS lock/unlock/wait work on the inode if rc != 0.

If we are closing the handle, the SMB server is supposed to remove any
locks associated with it. Similarly, cifs.ko frees and wakes up any
lock and lock waiter when closing the file:

cifs_close()
  cifsFileInfo_put(file->private_data)
	/*
	 * Delete any outstanding lock records. We'll lose them when the file
	 * is closed anyway.
	 */
	down_write(&cifsi->lock_sem);
	list_for_each_entry_safe(li, tmp, &cifs_file->llist->locks, llist) {
		list_del(&li->llist);
		cifs_del_lock_waiters(li);
		kfree(li);
	}
	list_del(&cifs_file->llist->llist);
	kfree(cifs_file->llist);
	up_write(&cifsi->lock_sem);

So we can safely ignore unlocking failures in cifs_lock() if they
happen with the FL_CLOSE flag hint set as both the server and the
client take care of it during the actual closing.

This is not a proper fix for the unlocking failure but it's safe and
it seems to prevent the lock leakages and crashes the customer
experiences.
Signed-off-by: NAurelien Aptel <aaptel@suse.com>
Signed-off-by: NNeilBrown <neil@brown.name>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Acked-by: NPavel Shilovsky <pshilov@microsoft.com>

For debugging purposes we often have to be able to query
additional information only available via SMB3 FSCTL
from the server from user space tools (e.g. like
cifs-utils's smbinfo).  See MS-FSCC and MS-SMB2 protocol
specifications for more details.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

smb2_set_sparse does not return -errno, it returns a boolean where
true means success.
Change this to just ignore the return value just like the other callsites.

Additionally add code to handle the case where we must set the file sparse
and possibly also extending it.

Fixes xfstests: generic/236 generic/350 generic/420
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

As Sergey Senozhatsky pointed out __constant_cpu_to_le32()
is misspelled in a few definitions in the list of status
codes smb2status.h as __constanst_cpu_to_le32()
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>

This cleanup removes cifs specific code from SMB2/SMB3 code paths
which is cleaner and easier to maintain as the code to handle
special files is improved.  Below is an example creating special files
using 'sfu' mount option over SMB3 to Windows (with this patch)
(Note that to Samba server, support for saving dos attributes
has to be enabled for the SFU mount option to work).

In the future this will also make implementation of creating
special files as reparse points easier (as Windows NFS server does
for example).

   root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/char
   character special file

   root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/block
   block special file
Signed-off-by: NAurelien Aptel <aaptel@suse.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

Also updated a comment describing use of the GlobalMid_Lock
Signed-off-by: NSteve French <stfrench@microsoft.com>

Detected by CoverityScan CID#1438719 ("Unused Value")

buf is reset again before being used so these two lines of code
are useless.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

The passthrough queries from user space tools like smbinfo can be either
SMB3 QUERY_INFO or SMB3 FSCTL, but we are not checking for the latter.
Temporarily we return EOPNOTSUPP for SMB3 FSCTL passthrough requests
but once compounding fsctls is fixed can enable.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

Can be helpful in debugging various xfstests that are currently
skipped or failing due to missing features in our current
implementation of fallocate.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

This allows fallocate -z to work against a Windows2016 share.

This is due to the SMB3 ZERO_RANGE command does not modify the filesize.
To address this we will now append a compounded SET-INFO to update the
end-of-file information.

This brings xfstests generic/469 closer to working against a windows share.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>