linux-toradex.git/drivers/block, branch v4.4.115

loop: fix concurrent lo_open/lo_release

2018-02-03T16:04:24+00:00

commit ae6650163c66a7eff1acd6eb8b0f752dcfa8eba5 upstream.

范龙飞 reports that KASAN can report a use-after-free in __lock_acquire.
The reason is due to insufficient serialization in lo_release(), which
will continue to use the loop device even after it has decremented the
lo_refcnt to zero.

In the meantime, another process can come in, open the loop device
again as it is being shut down. Confusion ensues.

Reported-by: 范龙飞 
Signed-off-by: Linus Torvalds 
Signed-off-by: Jens Axboe 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

rbd: set max_segments to USHRT_MAX

2018-01-17T08:35:30+00:00

commit 21acdf45f4958135940f0b4767185cf911d4b010 upstream.

Commit d3834fefcfe5 ("rbd: bump queue_max_segments") bumped
max_segments (unsigned short) to max_hw_sectors (unsigned int).
max_hw_sectors is set to the number of 512-byte sectors in an object
and overflows unsigned short for 32M (largest possible) objects, making
the block layer resort to handing us single segment (i.e. single page
or even smaller) bios in that case.

Fixes: d3834fefcfe5 ("rbd: bump queue_max_segments")
Signed-off-by: Ilya Dryomov 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

zram: set physical queue limits to avoid array out of bounds accesses

2017-12-16T09:33:53+00:00

[ Upstream commit 0bc315381fe9ed9fb91db8b0e82171b645ac008f ]

zram can handle at most SECTORS_PER_PAGE sectors in a bio's bvec. When using
the NVMe over Fabrics loopback target which potentially sends a huge bulk of
pages attached to the bio's bvec this results in a kernel panic because of
array out of bounds accesses in zram_decompress_page().

Signed-off-by: Johannes Thumshirn 
Reviewed-by: Hannes Reinecke 
Reviewed-by: Sergey Senozhatsky 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

xen-blkback: don't leak stack data via response ring

2017-11-21T08:21:17+00:00

commit 089bc0143f489bd3a4578bdff5f4ca68fb26f341 upstream.

Rather than constructing a local structure instance on the stack, fill
the fields directly on the shared ring, just like other backends do.
Build on the fact that all response structure flavors are actually
identical (the old code did make this assumption too).

This is XSA-216.

Signed-off-by: Jan Beulich 
Reviewed-by: Konrad Rzeszutek Wilk 
Signed-off-by: Konrad Rzeszutek Wilk 
[bwh: Backported to 4.4: adjust context]
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

rbd: use GFP_NOIO for parent stat and data requests

2017-11-15T16:13:13+00:00

commit 1e37f2f84680fa7f8394fd444b6928e334495ccc upstream.

rbd_img_obj_exists_submit() and rbd_img_obj_parent_read_full() are on
the writeback path for cloned images -- we attempt a stat on the parent
object to see if it exists and potentially read it in to call copyup.
GFP_NOIO should be used instead of GFP_KERNEL here.

Link: http://tracker.ceph.com/issues/22014
Signed-off-by: Ilya Dryomov 
Reviewed-by: David Disseldorp 
[idryomov@gmail.com: backport to < 4.9: context]
Signed-off-by: Greg Kroah-Hartman

skd: Submit requests to firmware before triggering the doorbell

2017-09-27T09:00:14+00:00

commit 5fbd545cd3fd311ea1d6e8be4cedddd0ee5684c7 upstream.

Ensure that the members of struct skd_msg_buf have been transferred
to the PCIe adapter before the doorbell is triggered. This patch
avoids that I/O fails sporadically and that the following error
message is reported:

(skd0:STM000196603:[0000:00:09.0]): Completion mismatch comp_id=0x0000 skreq=0x0400 new=0x0000

Signed-off-by: Bart Van Assche 
Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Johannes Thumshirn 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

skd: Avoid that module unloading triggers a use-after-free

2017-09-27T09:00:14+00:00

commit 7277cc67b3916eed47558c64f9c9c0de00a35cda upstream.

Since put_disk() triggers a disk_release() call and since that
last function calls blk_put_queue() if disk->queue != NULL, clear
the disk->queue pointer before calling put_disk(). This avoids
that unloading the skd kernel module triggers the following
use-after-free:

WARNING: CPU: 8 PID: 297 at lib/refcount.c:128 refcount_sub_and_test+0x70/0x80
refcount_t: underflow; use-after-free.
CPU: 8 PID: 297 Comm: kworker/8:1 Not tainted 4.11.10-300.fc26.x86_64 #1
Workqueue: events work_for_cpu_fn
Call Trace:
 dump_stack+0x63/0x84
 __warn+0xcb/0xf0
 warn_slowpath_fmt+0x5a/0x80
 refcount_sub_and_test+0x70/0x80
 refcount_dec_and_test+0x11/0x20
 kobject_put+0x1f/0x50
 blk_put_queue+0x15/0x20
 disk_release+0xae/0xf0
 device_release+0x32/0x90
 kobject_release+0x67/0x170
 kobject_put+0x2b/0x50
 put_disk+0x17/0x20
 skd_destruct+0x5c/0x890 [skd]
 skd_pci_probe+0x124d/0x13a0 [skd]
 local_pci_probe+0x42/0xa0
 work_for_cpu_fn+0x14/0x20
 process_one_work+0x19e/0x470
 worker_thread+0x1dc/0x4a0
 kthread+0x125/0x140
 ret_from_fork+0x25/0x30

Signed-off-by: Bart Van Assche 
Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Johannes Thumshirn 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

virtio_blk: fix panic in initialization error path

2017-08-11T16:08:58+00:00

[ Upstream commit 6bf6b0aa3da84a3d9126919a94c49c0fb7ee2fb3 ]

If blk_mq_init_queue() returns an error, it gets assigned to
vblk->disk->queue. Then, when we call put_disk(), we end up calling
blk_put_queue() with the ERR_PTR, causing a bad dereference. Fix it by
only assigning to vblk->disk->queue on success.

Signed-off-by: Omar Sandoval 
Reviewed-by: Jeff Moyer 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

xen/blkback: don't use xen_blkif_get() in xen-blkback kthread

2017-08-07T02:19:43+00:00

commit a24fa22ce22ae302b3bf8f7008896d52d5d57b8d upstream.

There is no need to use xen_blkif_get()/xen_blkif_put() in the kthread
of xen-blkback. Thread stopping is synchronous and using the blkif
reference counting in the kthread will avoid to ever let the reference
count drop to zero at the end of an I/O running concurrent to
disconnecting and multiple rings.

Setting ring->xenblkd to NULL after stopping the kthread isn't needed
as the kthread does this already.

Signed-off-by: Juergen Gross 
Tested-by: Steven Haigh 
Acked-by: Roger Pau Monné 
Signed-off-by: Konrad Rzeszutek Wilk 
Signed-off-by: Greg Kroah-Hartman

xen/blkback: don't free be structure too early

2017-08-07T02:19:43+00:00

commit 71df1d7ccad1c36f7321d6b3b48f2ea42681c363 upstream.

The be structure must not be freed when freeing the blkif structure
isn't done. Otherwise a use-after-free of be when unmapping the ring
used for communicating with the frontend will occur in case of a
late call of xenblk_disconnect() (e.g. due to an I/O still active
when trying to disconnect).

Signed-off-by: Juergen Gross 
Tested-by: Steven Haigh 
Acked-by: Roger Pau Monné 
Signed-off-by: Konrad Rzeszutek Wilk 
Signed-off-by: Greg Kroah-Hartman