linux-stable.git/drivers, branch v5.0.5

loop: access lo_backing_file only when the loop device is Lo_bound

2019-03-27T05:17:59+00:00

commit f7c8a4120eedf24c36090b7542b179ff7a649219 upstream.

Commit 758a58d0bc67 ("loop: set GENHD_FL_NO_PART_SCAN after
blkdev_reread_part()") separates "lo->lo_backing_file = NULL" and
"lo->lo_state = Lo_unbound" into different critical regions protected by
loop_ctl_mutex.

However, there is below race that the NULL lo->lo_backing_file would be
accessed when the backend of a loop is another loop device, e.g., loop0's
backend is a file, while loop1's backend is loop0.

loop0's backend is file            loop1's backend is loop0

__loop_clr_fd()
  mutex_lock(&loop_ctl_mutex);
  lo->lo_backing_file = NULL; --> set to NULL
  mutex_unlock(&loop_ctl_mutex);
                                   loop_set_fd()
                                     mutex_lock_killable(&loop_ctl_mutex);
                                     loop_validate_file()
                                       f = l->lo_backing_file; --> NULL
                                         access if loop0 is not Lo_unbound
  mutex_lock(&loop_ctl_mutex);
  lo->lo_state = Lo_unbound;
  mutex_unlock(&loop_ctl_mutex);

lo->lo_backing_file should be accessed only when the loop device is
Lo_bound.

In fact, the problem has been introduced already in commit 7ccd0791d985
("loop: Push loop_ctl_mutex down into loop_clr_fd()") after which
loop_validate_file() could see devices in Lo_rundown state with which it
did not count. It was harmless at that point but still.

Fixes: 7ccd0791d985 ("loop: Push loop_ctl_mutex down into loop_clr_fd()")
Reported-by: syzbot+9bdc1adc1c55e7fe765b@syzkaller.appspotmail.com
Signed-off-by: Dongli Zhang 
Reviewed-by: Jan Kara 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

RDMA/cma: Rollback source IP address if failing to acquire device

2019-03-27T05:17:58+00:00

commit 5fc01fb846bce8fa6d5f95e2625b8ce0f8e86810 upstream.

If cma_acquire_dev_by_src_ip() returns error in addr_handler(), the
device state changes back to RDMA_CM_ADDR_BOUND but the resolved source
IP address is still left. After that, if rdma_destroy_id() is called
after rdma_listen(), the device is freed without removed from
listen_any_list in cma_cancel_operation(). Revert to the previous IP
address if acquiring device fails.

Reported-by: syzbot+f3ce716af730c8f96637@syzkaller.appspotmail.com
Signed-off-by: Myungho Jung 
Reviewed-by: Parav Pandit 
Signed-off-by: Jason Gunthorpe 
Signed-off-by: Greg Kroah-Hartman

drm/vkms: Fix flush_work() without INIT_WORK().

2019-03-27T05:17:58+00:00

commit b30b61ff6b1dc37f276cf56a8328b80086a3ffca upstream.

syzbot is hitting a lockdep warning [1] because flush_work() is called
without INIT_WORK() after kzalloc() at vkms_atomic_crtc_reset().

Commit 6c234fe37c57627a ("drm/vkms: Implement CRC debugfs API") added
INIT_WORK() to only vkms_atomic_crtc_duplicate_state() side. Assuming
that lifecycle of crc_work is appropriately managed, fix this problem
by adding INIT_WORK() to vkms_atomic_crtc_reset() side.

[1] https://syzkaller.appspot.com/bug?id=a5954455fcfa51c29ca2ab55b203076337e1c770

Reported-and-tested-by: syzbot 
Signed-off-by: Tetsuo Handa 
Reviewed-by: Shayenne Moura 
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/1547829823-9877-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_ldisc: Postpone HCI_UART_PROTO_READY bit set in hci_uart_set_proto()

2019-03-27T05:17:58+00:00

commit 56897b217a1d0a91c9920cb418d6b3fe922f590a upstream.

task A:                                task B:
hci_uart_set_proto                     flush_to_ldisc
 - p->open(hu) -> h5_open  //alloc h5  - receive_buf
 - set_bit HCI_UART_PROTO_READY         - tty_port_default_receive_buf
 - hci_uart_register_dev                 - tty_ldisc_receive_buf
                                          - hci_uart_tty_receive
				           - test_bit HCI_UART_PROTO_READY
				            - h5_recv
 - clear_bit HCI_UART_PROTO_READY             while() {
 - p->open(hu) -> h5_close //free h5
				              - h5_rx_3wire_hdr
				               - h5_reset()  //use-after-free
                                              }

It could use ioctl to set hci uart proto, but there is
a use-after-free issue when hci_uart_register_dev() fail in
hci_uart_set_proto(), see stack above, fix this by setting
HCI_UART_PROTO_READY bit only when hci_uart_register_dev()
return success.

Reported-by: syzbot+899a33dc0fa0dbaf06a6@syzkaller.appspotmail.com
Signed-off-by: Kefeng Wang 
Reviewed-by: Jeremy Cline 
Signed-off-by: Marcel Holtmann 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_ldisc: Initialize hci_dev before open()

2019-03-27T05:17:57+00:00

commit 32a7b4cbe93b0a0ef7e63d31ca69ce54736c4412 upstream.

The hci_dev struct hdev is referenced in work queues and timers started
by open() in some protocols. This creates a race between the
initialization function and the work or timer which can result hdev
being dereferenced while it is still null.

The syzbot report contains a reliable reproducer which causes a null
pointer dereference of hdev in hci_uart_write_work() by making the
memory allocation for hdev fail.

To fix this, ensure hdev is valid from before calling a protocol's
open() until after calling a protocol's close().

Reported-by: syzbot+257790c15bcdef6fe00c@syzkaller.appspotmail.com
Signed-off-by: Jeremy Cline 
Signed-off-by: Marcel Holtmann 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_uart: Check if socket buffer is ERR_PTR in h4_recv_buf()

2019-03-27T05:17:57+00:00

commit 1dc2d785156cbdc80806c32e8d2c7c735d0b4721 upstream.

h4_recv_buf() callers store the return value to socket buffer and
recursively pass the buffer to h4_recv_buf() without protection. So,
ERR_PTR returned from h4_recv_buf() can be dereferenced, if called again
before setting the socket buffer to NULL from previous error. Check if
skb is ERR_PTR in h4_recv_buf().

Reported-by: syzbot+017a32f149406df32703@syzkaller.appspotmail.com
Signed-off-by: Myungho Jung 
Signed-off-by: Marcel Holtmann 
Signed-off-by: Greg Kroah-Hartman

media: v4l2-ctrls.c/uvc: zero v4l2_event

2019-03-27T05:17:56+00:00

commit f45f3f753b0a3d739acda8e311b4f744d82dc52a upstream.

Control events can leak kernel memory since they do not fully zero the
event. The same code is present in both v4l2-ctrls.c and uvc_ctrl.c, so
fix both.

It appears that all other event code is properly zeroing the structure,
it's these two places.

Signed-off-by: Hans Verkuil 
Reported-by: syzbot+4f021cf3697781dbd9fb@syzkaller.appspotmail.com
Reviewed-by: Laurent Pinchart 
Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Greg Kroah-Hartman

clocksource/drivers/riscv: Fix clocksource mask

2019-03-27T05:17:55+00:00

commit 32d0be018f6f5ee2d5d19c4795304613560814cf upstream.

For all riscv architectures (RV32, RV64 and RV128), the clocksource
is a 64 bit incrementing counter.

Fix the clock source mask accordingly.

Tested on both 64bit and 32 bit virt machine in QEMU.

Fixes: 62b019436814 ("clocksource: new RISC-V SBI timer driver")
Signed-off-by: Atish Patra 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Anup Patel 
Cc: Albert Ou 
Cc: Daniel Lezcano 
Cc: linux-riscv@lists.infradead.org
Cc: Palmer Dabbelt 
Cc: Anup Patel 
Cc: Damien Le Moal 
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190322215411.19362-1-atish.patra@wdc.com
Signed-off-by: Greg Kroah-Hartman

irqchip/gic-v3-its: Fix comparison logic in lpi_range_cmp

2019-03-27T05:17:55+00:00

commit 89dc891792c2e046b030f87600109c22209da32e upstream.

The lpi_range_list is supposed to be sorted in ascending order of
->base_id (at least if the range merging is to work), but the current
comparison function returns a positive value if rb->base_id >
ra->base_id, which means that list_sort() will put A after B in that
case - and vice versa, of course.

Fixes: 880cb3cddd16 (irqchip/gic-v3-its: Refactor LPI allocator)
Cc: stable@vger.kernel.org (v4.19+)
Signed-off-by: Rasmus Villemoes 
Signed-off-by: Marc Zyngier 
Signed-off-by: Greg Kroah-Hartman

scsi: ibmvscsi: Fix empty event pool access during host removal

2019-03-27T05:17:54+00:00

commit 7f5203c13ba8a7b7f9f6ecfe5a4d5567188d7835 upstream.

The event pool used for queueing commands is destroyed fairly early in the
ibmvscsi_remove() code path. Since, this happens prior to the call so
scsi_remove_host() it is possible for further calls to queuecommand to be
processed which manifest as a panic due to a NULL pointer dereference as
seen here:

PANIC: "Unable to handle kernel paging request for data at address
0x00000000"

Context process backtrace:

DSISR: 0000000042000000 ????Syscall Result: 0000000000000000
4 [c000000002cb3820] memcpy_power7 at c000000000064204
[Link Register] [c000000002cb3820] ibmvscsi_send_srp_event at d000000003ed14a4
5 [c000000002cb3920] ibmvscsi_send_srp_event at d000000003ed14a4 [ibmvscsi] ?(unreliable)
6 [c000000002cb39c0] ibmvscsi_queuecommand at d000000003ed2388 [ibmvscsi]
7 [c000000002cb3a70] scsi_dispatch_cmd at d00000000395c2d8 [scsi_mod]
8 [c000000002cb3af0] scsi_request_fn at d00000000395ef88 [scsi_mod]
9 [c000000002cb3be0] __blk_run_queue at c000000000429860
10 [c000000002cb3c10] blk_delay_work at c00000000042a0ec
11 [c000000002cb3c40] process_one_work at c0000000000dac30
12 [c000000002cb3cd0] worker_thread at c0000000000db110
13 [c000000002cb3d80] kthread at c0000000000e3378
14 [c000000002cb3e30] ret_from_kernel_thread at c00000000000982c

The kernel buffer log is overfilled with this log:

[11261.952732] ibmvscsi: found no event struct in pool!

This patch reorders the operations during host teardown. Start by calling
the SRP transport and Scsi_Host remove functions to flush any outstanding
work and set the host offline. LLDD teardown follows including destruction
of the event pool, freeing the Command Response Queue (CRQ), and unmapping
any persistent buffers. The event pool destruction is protected by the
scsi_host lock, and the pool is purged prior of any requests for which we
never received a response. Finally, move the removal of the scsi host from
our global list to the end so that the host is easily locatable for
debugging purposes during teardown.

Cc:  # v2.6.12+
Signed-off-by: Tyrel Datwyler 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Greg Kroah-Hartman