1. 15 Mar, 2016 4 commits
    • Johannes Berg's avatar
      cfg80211/wext: fix message ordering · 11eee1c3
      Johannes Berg authored
      commit cb150b9d upstream.
      
      Since cfg80211 frequently takes actions from its netdev notifier
      call, wireless extensions messages could still be ordered badly
      since the wext netdev notifier, since wext is built into the
      kernel, runs before the cfg80211 netdev notifier. For example,
      the following can happen:
      
      5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default
          link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff
      5: wlan1: <BROADCAST,MULTICAST,UP>
          link/ether
      
      when setting the interface down causes the wext message.
      
      To also fix this, export the wireless_nlevent_flush() function
      and also call it from the cfg80211 notifier.
      Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      11eee1c3
    • Johannes Berg's avatar
      wext: fix message delay/ordering · e5f07718
      Johannes Berg authored
      commit 8bf86273 upstream.
      
      Beniamino reported that he was getting an RTM_NEWLINK message for a
      given interface, after the RTM_DELLINK for it. It turns out that the
      message is a wireless extensions message, which was sent because the
      interface had been connected and disconnection while it was deleted
      caused a wext message.
      
      For its netlink messages, wext uses RTM_NEWLINK, but the message is
      without all the regular rtnetlink attributes, so "ip monitor link"
      prints just rudimentary information:
      
      5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN group default
          link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff
      Deleted 5: wlan1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default
          link/ether 02:00:00:00:01:00 brd ff:ff:ff:ff:ff:ff
      5: wlan1: <BROADCAST,MULTICAST,UP>
          link/ether
      (from my hwsim reproduction)
      
      This can cause userspace to get confused since it doesn't expect an
      RTM_NEWLINK message after RTM_DELLINK.
      
      The reason for this is that wext schedules a worker to send out the
      messages, and the scheduling delay can cause the messages to get out
      to userspace in different order.
      
      To fix this, have wext register a netdevice notifier and flush out
      any pending messages when netdevice state changes. This fixes any
      ordering whenever the original message wasn't sent by a notifier
      itself.
      Reported-by: default avatarBeniamino Galvani <bgalvani@redhat.com>
      Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      e5f07718
    • Vladis Dronov's avatar
      Input: aiptek - fix crash on detecting device without endpoints · 6d286755
      Vladis Dronov authored
      commit 8e20cf2b upstream.
      
      The aiptek driver crashes in aiptek_probe() when a specially crafted USB
      device without endpoints is detected. This fix adds a check that the device
      has proper configuration expected by the driver. Also an error return value
      is changed to more matching one in one of the error paths.
      Reported-by: default avatarRalf Spenneberg <ralf@spenneberg.net>
      Signed-off-by: default avatarVladis Dronov <vdronov@redhat.com>
      Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      6d286755
    • Martin Schwidefsky's avatar
      s390/mm: four page table levels vs. fork · 5b62f74b
      Martin Schwidefsky authored
      commit 3446c13b upstream.
      
      The fork of a process with four page table levels is broken since
      git commit 6252d702 "[S390] dynamic page tables."
      
      All new mm contexts are created with three page table levels and
      an asce limit of 4TB. If the parent has four levels dup_mmap will
      add vmas to the new context which are outside of the asce limit.
      The subsequent call to copy_page_range will walk the three level
      page table structure of the new process with non-zero pgd and pud
      indexes. This leads to memory clobbers as the pgd_index *and* the
      pud_index is added to the mm->pgd pointer without a pgd_deref
      in between.
      
      The init_new_context() function is selecting the number of page
      table levels for a new context. The function is used by mm_init()
      which in turn is called by dup_mm() and mm_alloc(). These two are
      used by fork() and exec(). The init_new_context() function can
      distinguish the two cases by looking at mm->context.asce_limit,
      for fork() the mm struct has been copied and the number of page
      table levels may not change. For exec() the mm_alloc() function
      set the new mm structure to zero, in this case a three-level page
      table is created as the temporary stack space is located at
      STACK_TOP_MAX = 4TB.
      
      This fixes CVE-2016-2143.
      Reported-by: default avatarMarcin Kościelnicki <koriakin@0x04.net>
      Reviewed-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      5b62f74b
  2. 10 Mar, 2016 36 commits