[ Upstream commit c6a45ee7607de3a350008630f4369b1b5ac80884 ]
ublk_ch_uring_cmd_local() may jump to the out label before
initialising the io pointer. This will cause trouble if DEBUG is
defined, because the pr_devel() call dereferences io. Clang reports:
drivers/block/ublk_drv.c:2403:6: error: variable 'io' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
2403 | if (tag >= ub->dev_info.queue_depth)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/block/ublk_drv.c:2492:32: note: uninitialized use occurs here
2492 | __func__, cmd_op, tag, ret, io->flags);
|
Fix this by initialising io to NULL and checking it before
dereferencing it.
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver")
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 79bd8c9814a273fa7ba43399e1c07adec3fc95db ]
With 6e0a48552b8c (ps3disk: use memcpy_{from,to}_bvec) converting
ps3disk to new bvec helpers, incrementing the offset was accidently
lost, corrupting consecutive buffers. Restore index for non-corrupted
data transfers.
Fixes: 6e0a48552b8c (ps3disk: use memcpy_{from,to}_bvec)
Signed-off-by: René Rebe <rene@exactco.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1649714b930f9ea6233ce0810ba885999da3b5d4 ]
There is one use-after-free warning when running NBD_CMD_CONNECT and
NBD_CLEAR_SOCK:
nbd_genl_connect
nbd_alloc_and_init_config // config_refs=1
nbd_start_device // config_refs=2
set NBD_RT_HAS_CONFIG_REF open nbd // config_refs=3
recv_work done // config_refs=2
NBD_CLEAR_SOCK // config_refs=1
close nbd // config_refs=0
refcount_inc -> uaf
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 24 PID: 1014 at lib/refcount.c:25 refcount_warn_saturate+0x12e/0x290
nbd_genl_connect+0x16d0/0x1ab0
genl_family_rcv_msg_doit+0x1f3/0x310
genl_rcv_msg+0x44a/0x790
The issue can be easily reproduced by adding a small delay before
refcount_inc(&nbd->config_refs) in nbd_genl_connect():
mutex_unlock(&nbd->config_lock);
if (!ret) {
set_bit(NBD_RT_HAS_CONFIG_REF, &config->runtime_flags);
+ printk("before sleep\n");
+ mdelay(5 * 1000);
+ printk("after sleep\n");
refcount_inc(&nbd->config_refs);
nbd_connect_reply(info, nbd->index);
}
Fixes: e46c7287b1c2 ("nbd: add a basic netlink interface")
Signed-off-by: Zheng Qixing <zhengqixing@huawei.com>
Reviewed-by: Yu Kuai <yukuai@fnnas.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9517b82d8d422d426a988b213fdd45c6b417b86d ]
There is one uaf issue in recv_work when running NBD_CLEAR_SOCK and
NBD_CMD_RECONFIGURE:
nbd_genl_connect // conf_ref=2 (connect and recv_work A)
nbd_open // conf_ref=3
recv_work A done // conf_ref=2
NBD_CLEAR_SOCK // conf_ref=1
nbd_genl_reconfigure // conf_ref=2 (trigger recv_work B)
close nbd // conf_ref=1
recv_work B
config_put // conf_ref=0
atomic_dec(&config->recv_threads); -> UAF
Or only running NBD_CLEAR_SOCK:
nbd_genl_connect // conf_ref=2
nbd_open // conf_ref=3
NBD_CLEAR_SOCK // conf_ref=2
close nbd
nbd_release
config_put // conf_ref=1
recv_work
config_put // conf_ref=0
atomic_dec(&config->recv_threads); -> UAF
Commit 87aac3a80af5 ("nbd: call nbd_config_put() before notifying the
waiter") moved nbd_config_put() to run before waking up the waiter in
recv_work, in order to ensure that nbd_start_device_ioctl() would not
be woken up while nbd->task_recv was still uncleared.
However, in nbd_start_device_ioctl(), after being woken up it explicitly
calls flush_workqueue() to make sure all current works are finished.
Therefore, there is no need to move the config put ahead of the wakeup.
Move nbd_config_put() to the end of recv_work, so that the reference is
held for the whole lifetime of the worker thread. This makes sure the
config cannot be freed while recv_work is still running, even if clear
+ reconfigure interleave.
In addition, we don't need to worry about recv_work dropping the last
nbd_put (which causes deadlock):
path A (netlink with NBD_CFLAG_DESTROY_ON_DISCONNECT):
connect // nbd_refs=1 (trigger recv_work)
open nbd // nbd_refs=2
NBD_CLEAR_SOCK
close nbd
nbd_release
nbd_disconnect_and_put
flush_workqueue // recv_work done
nbd_config_put
nbd_put // nbd_refs=1
nbd_put // nbd_refs=0
queue_work
path B (netlink without NBD_CFLAG_DESTROY_ON_DISCONNECT):
connect // nbd_refs=2 (trigger recv_work)
open nbd // nbd_refs=3
NBD_CLEAR_SOCK // conf_refs=2
close nbd
nbd_release
nbd_config_put // conf_refs=1
nbd_put // nbd_refs=2
recv_work done // conf_refs=0, nbd_refs=1
rmmod // nbd_refs=0
Reported-by: syzbot+56fbf4c7ddf65e95c7cc@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6907edce.a70a0220.37351b.0014.GAE@google.com/T/
Fixes: 87aac3a80af5 ("nbd: make the config put is called before the notifying the waiter")
Depends-on: e2daec488c57 ("nbd: Fix hungtask when nbd_config_put")
Signed-off-by: Zheng Qixing <zhengqixing@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Pull block fixes from Jens Axboe:
- Fix blk-crypto reporting EIO when EINVAL is the correct error code
- Two bug fixes for the block zone support
- NVME pull request via Keith:
- Target side authentication fixup
- Peer-to-peer metadata fixup
- null_blk DMA alignment fix
* tag 'block-6.18-20251031' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
null_blk: set dma alignment to logical block size
blk-crypto: use BLK_STS_INVAL for alignment errors
block: make REQ_OP_ZONE_OPEN a write operation
block: fix op_is_zone_mgmt() to handle REQ_OP_ZONE_RESET_ALL
nvme-pci: use blk_map_iter for p2p metadata
nvmet-auth: update sc_c in host response
This driver assumes that bio vectors are memory aligned to the logical
block size, so set the queue limit to reflect that.
Unless we set up the limit based on the logical block size, we will go
out of page bounds in copy_to_nullb / copy_from_nullb.
Apparently this wasn't noticed so far because none of the tests generate
such buffers, but since commit 851c4c96db00 ("xfs: implement
XFS_IOC_DIOINFO in terms of vfs_getattr") xfstests generates unaligned
I/O, which now lead to memory corruption when using null_blk devices
with 4k block size.
Fixes: bf8d08532bc1 ("iomap: add support for dma aligned direct-io")
Fixes: b1a000d3b8ec ("block: relax direct io memory alignment")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull block fixes from Jens Axboe:
- Fix dma alignment for PI
- Fix selinux bogosity with nbd, where sendmsg would get rejected
* tag 'block-6.18-20251023' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
block: require LBA dma_alignment when using PI
nbd: override creds to kernel when calling sock_{send,recv}msg()
sock_{send,recv}msg() internally calls security_socket_{send,recv}msg(),
which does security checks (e.g. SELinux) for socket access against the
current task. However, _sock_xmit() in drivers/block/nbd.c may be called
indirectly from a userspace syscall, where the NBD socket access would
be incorrectly checked against the calling userspace task (which simply
tries to read/write a file that happens to reside on an NBD device).
To fix this, temporarily override creds to kernel ones before calling
the sock_*() functions. This allows the security modules to recognize
this as internal access by the kernel, which will normally be allowed.
A way to trigger the issue is to do the following (on a system with
SELinux set to enforcing):
### Create nbd device:
truncate -s 256M /tmp/testfile
nbd-server localhost:10809 /tmp/testfile
### Connect to the nbd server:
nbd-client localhost
### Create mdraid array
mdadm --create -l 1 -n 2 /dev/md/testarray /dev/nbd0 missing
After these steps, assuming the SELinux policy doesn't allow the
unexpected access pattern, errors will be visible on the kernel console:
[ 142.204243] nbd0: detected capacity change from 0 to 524288
[ 165.189967] md: async del_gendisk mode will be removed in future, please upgrade to mdadm-4.5+
[ 165.252299] md/raid1:md127: active with 1 out of 2 mirrors
[ 165.252725] md127: detected capacity change from 0 to 522240
[ 165.255434] block nbd0: Send control failed (result -13)
[ 165.255718] block nbd0: Request send failed, requeueing
[ 165.256006] block nbd0: Dead connection, failed to find a fallback
[ 165.256041] block nbd0: Receive control failed (result -32)
[ 165.256423] block nbd0: shutting down sockets
[ 165.257196] I/O error, dev nbd0, sector 2048 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.257736] Buffer I/O error on dev md127, logical block 0, async page read
[ 165.258263] I/O error, dev nbd0, sector 2048 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.259376] Buffer I/O error on dev md127, logical block 0, async page read
[ 165.259920] I/O error, dev nbd0, sector 2048 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.260628] Buffer I/O error on dev md127, logical block 0, async page read
[ 165.261661] ldm_validate_partition_table(): Disk read failed.
[ 165.262108] I/O error, dev nbd0, sector 2048 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.262769] Buffer I/O error on dev md127, logical block 0, async page read
[ 165.263697] I/O error, dev nbd0, sector 2048 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.264412] Buffer I/O error on dev md127, logical block 0, async page read
[ 165.265412] I/O error, dev nbd0, sector 2048 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.265872] Buffer I/O error on dev md127, logical block 0, async page read
[ 165.266378] I/O error, dev nbd0, sector 2048 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.267168] Buffer I/O error on dev md127, logical block 0, async page read
[ 165.267564] md127: unable to read partition table
[ 165.269581] I/O error, dev nbd0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.269960] Buffer I/O error on dev nbd0, logical block 0, async page read
[ 165.270316] I/O error, dev nbd0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.270913] Buffer I/O error on dev nbd0, logical block 0, async page read
[ 165.271253] I/O error, dev nbd0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2
[ 165.271809] Buffer I/O error on dev nbd0, logical block 0, async page read
[ 165.272074] ldm_validate_partition_table(): Disk read failed.
[ 165.272360] nbd0: unable to read partition table
[ 165.289004] ldm_validate_partition_table(): Disk read failed.
[ 165.289614] nbd0: unable to read partition table
The corresponding SELinux denial on Fedora/RHEL will look like this
(assuming it's not silenced):
type=AVC msg=audit(1758104872.510:116): avc: denied { write } for pid=1908 comm="mdadm" laddr=::1 lport=32772 faddr=::1 fport=10809 scontext=system_u:system_r:mdadm_t:s0-s0:c0.c1023 tcontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tclass=tcp_socket permissive=0
The respective backtrace looks like this:
@security[mdadm, -13,
handshake_exit+221615650
handshake_exit+221615650
handshake_exit+221616465
security_socket_sendmsg+5
sock_sendmsg+106
handshake_exit+221616150
sock_sendmsg+5
__sock_xmit+162
nbd_send_cmd+597
nbd_handle_cmd+377
nbd_queue_rq+63
blk_mq_dispatch_rq_list+653
__blk_mq_do_dispatch_sched+184
__blk_mq_sched_dispatch_requests+333
blk_mq_sched_dispatch_requests+38
blk_mq_run_hw_queue+239
blk_mq_dispatch_plug_list+382
blk_mq_flush_plug_list.part.0+55
__blk_flush_plug+241
__submit_bio+353
submit_bio_noacct_nocheck+364
submit_bio_wait+84
__blkdev_direct_IO_simple+232
blkdev_read_iter+162
vfs_read+591
ksys_read+95
do_syscall_64+92
entry_SYSCALL_64_after_hwframe+120
]: 1
The issue has started to appear since commit 060406c61c7c ("block: add
plug while submitting IO").
Cc: Ming Lei <ming.lei@redhat.com>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2348878
Fixes: 060406c61c7c ("block: add plug while submitting IO")
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull block fixes from Jens Axboe: - Don't include __GFP_NOWARN for loop worker allocation, as it already uses GFP_NOWAIT which has __GFP_NOWARN set already - Small series cleaning up the recent bio_iov_iter_get_pages() changes - loop fix for leaking the backing reference file, if validation fails - Update of a comment pertaining to disk/partition stat locking * tag 'block-6.18-20251009' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: loop: remove redundant __GFP_NOWARN flag block: move bio_iov_iter_get_bdev_pages to block/fops.c iomap: open code bio_iov_iter_get_bdev_pages block: rename bio_iov_iter_get_pages_aligned to bio_iov_iter_get_pages block: remove bio_iov_iter_get_pages block: Update a comment of disk statistics loop: fix backing file reference leak on validation error
GFP_NOWAIT already includes __GFP_NOWARN, so let's remove the redundant __GFP_NOWARN. Signed-off-by: Pedro Demarchi Gomes <pedrodemargomes@gmail.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>