linux-stable.git/drivers/block, branch v6.1.69

nbd: pass nbd_sock to nbd_read_reply() instead of index

2023-12-20T16:00:23+00:00

[ Upstream commit 98c598afc22d4e43c2ad91860b65996d0c099a5d ]

If a socket is processing ioctl 'NBD_SET_SOCK', config->socks might be
krealloc in nbd_add_socket(), and a garbage request is received now, a UAF
may occurs.

  T1
  nbd_ioctl
   __nbd_ioctl
    nbd_add_socket
     blk_mq_freeze_queue
				T2
  				recv_work
  				 nbd_read_reply
  				  sock_xmit
     krealloc config->socks
				   def config->socks

Pass nbd_sock to nbd_read_reply(). And introduce a new function
sock_xmit_recv(), which differs from sock_xmit only in the way it get
socket.

==================================================================
BUG: KASAN: use-after-free in sock_xmit+0x525/0x550
Read of size 8 at addr ffff8880188ec428 by task kworker/u12:1/18779

Workqueue: knbd4-recv recv_work
Call Trace:
 __dump_stack
 dump_stack+0xbe/0xfd
 print_address_description.constprop.0+0x19/0x170
 __kasan_report.cold+0x6c/0x84
 kasan_report+0x3a/0x50
 sock_xmit+0x525/0x550
 nbd_read_reply+0xfe/0x2c0
 recv_work+0x1c2/0x750
 process_one_work+0x6b6/0xf10
 worker_thread+0xdd/0xd80
 kthread+0x30a/0x410
 ret_from_fork+0x22/0x30

Allocated by task 18784:
 kasan_save_stack+0x1b/0x40
 kasan_set_track
 set_alloc_info
 __kasan_kmalloc
 __kasan_kmalloc.constprop.0+0xf0/0x130
 slab_post_alloc_hook
 slab_alloc_node
 slab_alloc
 __kmalloc_track_caller+0x157/0x550
 __do_krealloc
 krealloc+0x37/0xb0
 nbd_add_socket
 +0x2d3/0x880
 __nbd_ioctl
 nbd_ioctl+0x584/0x8e0
 __blkdev_driver_ioctl
 blkdev_ioctl+0x2a0/0x6e0
 block_ioctl+0xee/0x130
 vfs_ioctl
 __do_sys_ioctl
 __se_sys_ioctl+0x138/0x190
 do_syscall_64+0x33/0x40
 entry_SYSCALL_64_after_hwframe+0x61/0xc6

Freed by task 18784:
 kasan_save_stack+0x1b/0x40
 kasan_set_track+0x1c/0x30
 kasan_set_free_info+0x20/0x40
 __kasan_slab_free.part.0+0x13f/0x1b0
 slab_free_hook
 slab_free_freelist_hook
 slab_free
 kfree+0xcb/0x6c0
 krealloc+0x56/0xb0
 nbd_add_socket+0x2d3/0x880
 __nbd_ioctl
 nbd_ioctl+0x584/0x8e0
 __blkdev_driver_ioctl
 blkdev_ioctl+0x2a0/0x6e0
 block_ioctl+0xee/0x130
 vfs_ioctl
 __do_sys_ioctl
 __se_sys_ioctl+0x138/0x190
 do_syscall_64+0x33/0x40
 entry_SYSCALL_64_after_hwframe+0x61/0xc6

Signed-off-by: Li Nan 
Reviewed-by: Yu Kuai 
Reviewed-by: Ming Lei 
Link: https://lore.kernel.org/r/20230911023308.3467802-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

nbd: fold nbd config initialization into nbd_alloc_config()

2023-12-20T16:00:22+00:00

[ Upstream commit 1b59860540a4018e8071dc18d4893ec389506b7d ]

There are no functional changes, make the code cleaner and prepare to
fix null-ptr-dereference while accessing 'nbd->config'.

Signed-off-by: Li Nan 
Reviewed-by: Josef Bacik 
Link: https://lore.kernel.org/r/20231116162316.1740402-2-linan666@huaweicloud.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

virtio-blk: fix implicit overflow on virtio_max_dma_size

2023-11-28T17:07:02+00:00

[ Upstream commit fafb51a67fb883eb2dde352539df939a251851be ]

The following codes have an implicit conversion from size_t to u32:
(u32)max_size = (size_t)virtio_max_dma_size(vdev);

This may lead overflow, Ex (size_t)4G -> (u32)0. Once
virtio_max_dma_size() has a larger size than U32_MAX, use U32_MAX
instead.

Signed-off-by: zhenwei pi 
Message-Id: <20230904061045.510460-1-pizhenwei@bytedance.com>
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Sasha Levin

nbd: fix uaf in nbd_open

2023-11-20T10:52:17+00:00

[ Upstream commit 327462725b0f759f093788dfbcb2f1fd132f956b ]

Commit 4af5f2e03013 ("nbd: use blk_mq_alloc_disk and
blk_cleanup_disk") cleans up disk by blk_cleanup_disk() and it won't set
disk->private_data as NULL as before. UAF may be triggered in nbd_open()
if someone tries to open nbd device right after nbd_put() since nbd has
been free in nbd_dev_remove().

Fix this by implementing ->free_disk and free private data in it.

Fixes: 4af5f2e03013 ("nbd: use blk_mq_alloc_disk and blk_cleanup_disk")
Signed-off-by: Li Lingfeng 
Reviewed-by: Josef Bacik 
Link: https://lore.kernel.org/r/20231107103435.2074904-1-lilingfeng@huaweicloud.com
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

rbd: take header_rwsem in rbd_dev_refresh() only when updating

2023-10-10T20:00:37+00:00

commit 0b207d02bd9ab8dcc31b262ca9f60dbc1822500d upstream.

rbd_dev_refresh() has been holding header_rwsem across header and
parent info read-in unnecessarily for ages.  With commit 870611e4877e
("rbd: get snapshot context after exclusive lock is ensured to be
held"), the potential for deadlocks became much more real owning to
a) header_rwsem now nesting inside lock_rwsem and b) rw_semaphores
not allowing new readers after a writer is registered.

For example, assuming that I/O request 1, I/O request 2 and header
read-in request all target the same OSD:

1. I/O request 1 comes in and gets submitted
2. watch error occurs
3. rbd_watch_errcb() takes lock_rwsem for write, clears owner_cid and
   releases lock_rwsem
4. after reestablishing the watch, rbd_reregister_watch() calls
   rbd_dev_refresh() which takes header_rwsem for write and submits
   a header read-in request
5. I/O request 2 comes in: after taking lock_rwsem for read in
   __rbd_img_handle_request(), it blocks trying to take header_rwsem
   for read in rbd_img_object_requests()
6. another watch error occurs
7. rbd_watch_errcb() blocks trying to take lock_rwsem for write
8. I/O request 1 completion is received by the messenger but can't be
   processed because lock_rwsem won't be granted anymore
9. header read-in request completion can't be received, let alone
   processed, because the messenger is stranded

Change rbd_dev_refresh() to take header_rwsem only for actually
updating rbd_dev->header.  Header and parent info read-in don't need
any locking.

Cc: stable@vger.kernel.org # 0b035401c570: rbd: move rbd_dev_refresh() definition
Cc: stable@vger.kernel.org # 510a7330c82a: rbd: decouple header read-in from updating rbd_dev->header
Cc: stable@vger.kernel.org # c10311776f0a: rbd: decouple parent info read-in from updating rbd_dev
Cc: stable@vger.kernel.org
Fixes: 870611e4877e ("rbd: get snapshot context after exclusive lock is ensured to be held")
Signed-off-by: Ilya Dryomov 
Reviewed-by: Dongsheng Yang 
Signed-off-by: Sasha Levin

rbd: decouple parent info read-in from updating rbd_dev

2023-10-10T20:00:37+00:00

commit c10311776f0a8ddea2276df96e255625b07045a8 upstream.

Unlike header read-in, parent info read-in is already decoupled in
get_parent_info(), but it's buried in rbd_dev_v2_parent_info() along
with the processing logic.

Separate the initial read-in and update read-in logic into
rbd_dev_setup_parent() and rbd_dev_update_parent() respectively and
have rbd_dev_v2_parent_info() just populate struct parent_image_info
(i.e. what get_parent_info() did).  Some existing QoI issues, like
flatten of a standalone clone being disregarded on refresh, remain.

Signed-off-by: Ilya Dryomov 
Reviewed-by: Dongsheng Yang 
Signed-off-by: Sasha Levin

rbd: decouple header read-in from updating rbd_dev->header

2023-10-10T20:00:37+00:00

commit 510a7330c82a7754d5df0117a8589e8a539067c7 upstream.

Make rbd_dev_header_info() populate a passed struct rbd_image_header
instead of rbd_dev->header and introduce rbd_dev_update_header() for
updating mutable fields in rbd_dev->header upon refresh.  The initial
read-in of both mutable and immutable fields in rbd_dev_image_probe()
passes in rbd_dev->header so no update step is required there.

rbd_init_layout() is now called directly from rbd_dev_image_probe()
instead of individually in format 1 and format 2 implementations.

Signed-off-by: Ilya Dryomov 
Reviewed-by: Dongsheng Yang 
Signed-off-by: Sasha Levin

rbd: move rbd_dev_refresh() definition

2023-10-10T20:00:37+00:00

commit 0b035401c57021fc6c300272cbb1c5a889d4fe45 upstream.

Move rbd_dev_refresh() definition further down to avoid having to
move struct parent_image_info definition in the next commit.  This
spares some forward declarations too.

Signed-off-by: Ilya Dryomov 
Reviewed-by: Dongsheng Yang 
[idryomov@gmail.com: backport to 5.10-6.1: context]
Signed-off-by: Sasha Levin

null_blk: fix poll request timeout handling

2023-09-19T10:27:56+00:00

commit 5a26e45edb4690d58406178b5a9ea4c6dcf2c105 upstream.

When doing io_uring benchmark on /dev/nullb0, it's easy to crash the
kernel if poll requests timeout triggered, as reported by David. [1]

BUG: kernel NULL pointer dereference, address: 0000000000000008
Workqueue: kblockd blk_mq_timeout_work
RIP: 0010:null_timeout_rq+0x4e/0x91
Call Trace:
 ? null_timeout_rq+0x4e/0x91
 blk_mq_handle_expired+0x31/0x4b
 bt_iter+0x68/0x84
 ? bt_tags_iter+0x81/0x81
 __sbitmap_for_each_set.constprop.0+0xb0/0xf2
 ? __blk_mq_complete_request_remote+0xf/0xf
 bt_for_each+0x46/0x64
 ? __blk_mq_complete_request_remote+0xf/0xf
 ? percpu_ref_get_many+0xc/0x2a
 blk_mq_queue_tag_busy_iter+0x14d/0x18e
 blk_mq_timeout_work+0x95/0x127
 process_one_work+0x185/0x263
 worker_thread+0x1b5/0x227

This is indeed a race problem between null_timeout_rq() and null_poll().

null_poll()				null_timeout_rq()
  spin_lock(&nq->poll_lock)
  list_splice_init(&nq->poll_list, &list)
  spin_unlock(&nq->poll_lock)

  while (!list_empty(&list))
    req = list_first_entry()
    list_del_init()
    ...
    blk_mq_add_to_batch()
    // req->rq_next = NULL
					spin_lock(&nq->poll_lock)

					// rq->queuelist->next == NULL
					list_del_init(&rq->queuelist)

					spin_unlock(&nq->poll_lock)

Fix these problems by setting requests state to MQ_RQ_COMPLETE under
nq->poll_lock protection, in which null_timeout_rq() can safely detect
this race and early return.

Note this patch just fix the kernel panic when request timeout happen.

[1] https://lore.kernel.org/all/3893581.1691785261@warthog.procyon.org.uk/

Fixes: 0a593fbbc245 ("null_blk: poll queue support")
Reported-by: David Howells 
Tested-by: David Howells 
Reviewed-by: Ming Lei 
Signed-off-by: Chengming Zhou 
Link: https://lore.kernel.org/r/20230901120306.170520-2-chengming.zhou@linux.dev
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

ublk: remove check IO_URING_F_SQE128 in ublk_ch_uring_cmd

2023-08-30T14:11:11+00:00

commit 9c7c4bc986932218fd0df9d2a100509772028fb1 upstream.

sizeof(struct ublksrv_io_cmd) is 16bytes, which can be held in 64byte SQE,
so not necessary to check IO_URING_F_SQE128.

With this change, we get chance to save half SQ ring memory.

Fixed: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver")
Signed-off-by: Ming Lei 
Link: https://lore.kernel.org/r/20230220041413.1524335-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman