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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-16 01:04:08 +08:00
linux-next/drivers/isdn
Duoming Zhou 175302f6b7 mISDN: hfcpci: Fix use-after-free bug in hfcpci_softirq
The function hfcpci_softirq() is a timer handler. If it
is running, the timer_pending() will return 0 and the
del_timer_sync() in HFC_cleanup() will not be executed.
As a result, the use-after-free bug will happen. The
process is shown below:

    (cleanup routine)          |        (timer handler)
HFC_cleanup()                  | hfcpci_softirq()
 if (timer_pending(&hfc_tl))   |
   del_timer_sync()            |
 ...                           | ...
 pci_unregister_driver(hc)     |
  driver_unregister            |  driver_for_each_device
   bus_remove_driver           |   _hfcpci_softirq
    driver_detach              |   ...
     put_device(dev) //[1]FREE |
                               |    dev_get_drvdata(dev) //[2]USE

The device is deallocated is position [1] and used in
position [2].

Fix by removing the "timer_pending" check in HFC_cleanup(),
which makes sure that the hfcpci_softirq() have finished
before the resource is deallocated.

Fixes: 009fc857c5 ("mISDN: fix possible use-after-free in HFC_cleanup()")
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-09 19:11:54 +01:00
..
capi isdn: move from strlcpy with unused retval to strscpy 2022-08-22 17:54:03 -07:00
hardware mISDN: hfcpci: Fix use-after-free bug in hfcpci_softirq 2022-10-09 19:11:54 +01:00
mISDN mISDN: fix use-after-free bugs in l1oip timer handlers 2022-09-30 12:32:42 +01:00
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile isdn: capi: dead code removal 2019-12-11 09:12:38 +01:00