Pull io_uring fixes from Jens Axboe:
"Fix for two regressions in this cycle, both reported by the postgresql
use case.

One removes the added restriction on who can submit IO, making it
possible for rings shared across forks to do so. The other fixes an
issue for the same kind of use case, where one exiting process would
cancel all IO"

* tag 'io_uring-5.5-2020-01-26' of git://git.kernel.dk/linux-block:
io_uring: don't cancel all work on process exit
Revert "io_uring: only allow submit from owning task"

Pull block fix from Jens Axboe:
"Unfortunately this weekend we had a few last minute reports, one was
for block.

The partition disable for zoned devices was overly restrictive, it can
work (and be supported) just fine for host-aware variants.

Here's a fix ensuring that's the case so we don't break existing users
of that"

* tag 'block-5.5-2020-01-26' of git://git.kernel.dk/linux-block:
block: allow partitions on host aware zone devices

If we're sharing the ring across forks, then one process exiting means
that we cancel ALL work and prevent future work. This is overly
restrictive. As long as we cancel the work associated with the files
from the current task, it's safe to let others persist. Normal fd close
on exit will still wait (and cancel) pending work.

Fixes: fcb323cc53e2 ("io_uring: io_uring: add support for async work inheriting files")
Reported-by: Andres Freund <andres@anarazel.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull SCSI fixes from James Bottomley:
"Two last minute fixes, both in drivers.

The fnic one is a highly unlikely condition, but the RDMA one is a
recently introduced regression that causes a kernel warning to trigger
in every RDMA logon, which would be unsightly if it got into the final
release"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: RDMA/isert: Fix a recently introduced regression related to logout
scsi: fnic: do not queue commands during fwreset

Host-aware SMR drives can be used with the commands to explicitly manage
zone state, but they can also be used as normal disks. In the former
case it makes perfect sense to allow partitions on them, in the latter
it does not, just like for host managed devices. Add a check to
add_partition to allow partitions on host aware devices, but give
up any zone management capabilities in that case, which also catches
the previously missed case of adding a partition vs just scanning it.

Because sd can rescan the attribute at runtime it needs to check if
a disk has partitions, for which a new helper is added to genhd.h.

Fixes: 5eac3eb30c9a ("block: Remove partition support for zoned block devices")
Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This ends up being too restrictive for tasks that willingly fork and
share the ring between forks. Andres reports that this breaks his
postgresql work. Since we're close to 5.5 release, revert this change
for now.

Cc: stable@vger.kernel.org
Fixes: 44d282796f81 ("io_uring: only allow submit from owning task")
Reported-by: Andres Freund <andres@anarazel.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull vfs fix from Al Viro:
"Fix a use-after-free in do_last() handling of sysctl_protected_...
checks.

The use-after-free normally doesn't happen there, but race with
rename() and it becomes possible"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
do_last(): fetch directory ->i_mode and ->i_uid before it's too late

iscsit_close_connection() calls isert_wait_conn(). Due to commit
e9d3009cb936 both functions call target_wait_for_sess_cmds() although that
last function should be called only once. Fix this by removing the
target_wait_for_sess_cmds() call from isert_wait_conn() and by only calling
isert_wait_conn() after target_wait_for_sess_cmds().

Fixes: e9d3009cb936 ("scsi: target: iscsi: Wait for all commands to finish before freeing a session").
Link: https://lore.kernel.org/r/20200116044737.19507-1-bvanassche@acm.org
Reported-by: Rahul Kundu <rahul.kundu@chelsio.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Logical block size has type unsigned short. That means that it can be at
most 32768. However, there are architectures that can run with 64k pages
(for example arm64) and on these architectures, it may be possible to
create block devices with 64k block size.

For exmaple (run this on an architecture with 64k pages):

Mount will fail with this error because it tries to read the superblock using 2-sector
access:
device-mapper: writecache: I/O is not aligned, sector 2, size 1024, block size 65536
EXT4-fs (dm-0): unable to read superblock

This patch changes the logical block size from unsigned short to unsigned
int to avoid the overflow.

Cc: stable@vger.kernel.org
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

fds field of struct io_uring_files_update is problematic with regards
to compat user space, as pointer size is different in 32-bit, 32-on-64-bit,
and 64-bit user space. In order to avoid custom handling of compat in
the syscall implementation, make fds __u64 and use u64_to_user_ptr in
order to retrieve it. Also, align the field naturally and check that
no garbage is passed there.

Fixes: c3a31e605620c279 ("io_uring: add support for IORING_REGISTER_FILES_UPDATE")
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The afs filesystem needs to prohibit certain characters from cell names,
such as '/', as these are used to form filenames in procfs, leading to
the following warning being generated:

WARNING: CPU: 0 PID: 3489 at fs/proc/generic.c:178

Fix afs_alloc_cell() to disallow nonprintable characters, '/', '@' and
names that begin with a dot.

Remove the check for "@cell" as that is then redundant.

This can be tested by running:

echo add foo/.bar 1.2.3.4 >/proc/fs/afs/cells

Note that we will also need to deal with:

- Names ending in ".invalid" shouldn't be passed to the DNS.

- Names that contain non-valid domainname chars shouldn't be passed to
the DNS.

- DNS replies that say "your-dns-needs-immediate-attention.<gTLD>" and
replies containing A records that say 127.0.53.53 should be
considered invalid.
[https://www.icann.org/en/system/files/files/name-collision-mitigation-01aug14-en.pdf]

but these need to be dealt with by the kafs-client DNS program rather
than the kernel.

Reported-by: syzbot+b904ba7c947a37b4b291@syzkaller.appspotmail.com
Cc: stable@kernel.org
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

may_create_in_sticky() call is done when we already have dropped the
reference to dir.

Fixes: 30aba6656f61e (namei: allow restricted O_CREAT of FIFOs and regular files)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

When a link is going down the driver will be calling fnic_cleanup_io(),
which will traverse all commands and calling 'done' for each found command.
While the traversal is handled under the host_lock, calling 'done' happens
after the host_lock is being dropped.

As fnic_queuecommand_lck() is being called with the host_lock held, it
might well be that it will pick the command being selected for abortion
from the above routine and enqueue it for sending, but then 'done' is being
called on that very command from the above routine.

Which of course confuses the hell out of the scsi midlayer.

So fix this by not queueing commands when fnic_cleanup_io is active.

Link: https://lore.kernel.org/r/20200116102053.62755-1-hare@suse.de
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>