1. 03 Nov, 2022 34 commits
  2. 02 Nov, 2022 6 commits
    • Luiz Augusto von Dentz's avatar
      Bluetooth: L2CAP: Fix attempting to access uninitialized memory · b1a2cd50
      Luiz Augusto von Dentz authored
      On l2cap_parse_conf_req the variable efs is only initialized if
      remote_efs has been set.
      
      CVE: CVE-2022-42895
      CC: stable@vger.kernel.org
      Reported-by: default avatarTamás Koczka <poprdi@google.com>
      Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
      Reviewed-by: default avatarTedd Ho-Jeong An <tedd.an@intel.com>
      b1a2cd50
    • Luiz Augusto von Dentz's avatar
      Bluetooth: L2CAP: Fix l2cap_global_chan_by_psm · f937b758
      Luiz Augusto von Dentz authored
      l2cap_global_chan_by_psm shall not return fixed channels as they are not
      meant to be connected by (S)PSM.
      Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
      Reviewed-by: default avatarTedd Ho-Jeong An <tedd.an@intel.com>
      f937b758
    • Luiz Augusto von Dentz's avatar
      Bluetooth: L2CAP: Fix accepting connection request for invalid SPSM · 711f8c3f
      Luiz Augusto von Dentz authored
      The Bluetooth spec states that the valid range for SPSM is from
      0x0001-0x00ff so it is invalid to accept values outside of this range:
      
        BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
        page 1059:
        Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges
      
      CVE: CVE-2022-42896
      CC: stable@vger.kernel.org
      Reported-by: default avatarTamás Koczka <poprdi@google.com>
      Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
      Reviewed-by: default avatarTedd Ho-Jeong An <tedd.an@intel.com>
      711f8c3f
    • Luiz Augusto von Dentz's avatar
      Bluetooth: hci_conn: Fix not restoring ISO buffer count on disconnect · 5638d9ea
      Luiz Augusto von Dentz authored
      When disconnecting an ISO link the controller may not generate
      HCI_EV_NUM_COMP_PKTS for unacked packets which needs to be restored in
      hci_conn_del otherwise the host would assume they are still in use and
      would not be able to use all the buffers available.
      
      Fixes: 26afbd82 ("Bluetooth: Add initial implementation of CIS connections")
      Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
      Tested-by: default avatarFrédéric Danis <frederic.danis@collabora.com>
      5638d9ea
    • Hawkins Jiawei's avatar
      Bluetooth: L2CAP: Fix memory leak in vhci_write · 7c9524d9
      Hawkins Jiawei authored
      Syzkaller reports a memory leak as follows:
      ====================================
      BUG: memory leak
      unreferenced object 0xffff88810d81ac00 (size 240):
        [...]
        hex dump (first 32 bytes):
          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
        backtrace:
          [<ffffffff838733d9>] __alloc_skb+0x1f9/0x270 net/core/skbuff.c:418
          [<ffffffff833f742f>] alloc_skb include/linux/skbuff.h:1257 [inline]
          [<ffffffff833f742f>] bt_skb_alloc include/net/bluetooth/bluetooth.h:469 [inline]
          [<ffffffff833f742f>] vhci_get_user drivers/bluetooth/hci_vhci.c:391 [inline]
          [<ffffffff833f742f>] vhci_write+0x5f/0x230 drivers/bluetooth/hci_vhci.c:511
          [<ffffffff815e398d>] call_write_iter include/linux/fs.h:2192 [inline]
          [<ffffffff815e398d>] new_sync_write fs/read_write.c:491 [inline]
          [<ffffffff815e398d>] vfs_write+0x42d/0x540 fs/read_write.c:578
          [<ffffffff815e3cdd>] ksys_write+0x9d/0x160 fs/read_write.c:631
          [<ffffffff845e0645>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
          [<ffffffff845e0645>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
          [<ffffffff84600087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
      ====================================
      
      HCI core will uses hci_rx_work() to process frame, which is queued to
      the hdev->rx_q tail in hci_recv_frame() by HCI driver.
      
      Yet the problem is that, HCI core may not free the skb after handling
      ACL data packets. To be more specific, when start fragment does not
      contain the L2CAP length, HCI core just copies skb into conn->rx_skb and
      finishes frame process in l2cap_recv_acldata(), without freeing the skb,
      which triggers the above memory leak.
      
      This patch solves it by releasing the relative skb, after processing
      the above case in l2cap_recv_acldata().
      
      Fixes: 4d7ea8ee ("Bluetooth: L2CAP: Fix handling fragmented length")
      Link: https://lore.kernel.org/all/0000000000000d0b1905e6aaef64@google.com/
      Reported-and-tested-by: syzbot+8f819e36e01022991cfa@syzkaller.appspotmail.com
      Signed-off-by: default avatarHawkins Jiawei <yin31149@gmail.com>
      Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
      7c9524d9
    • Zhengchao Shao's avatar
      Bluetooth: L2CAP: fix use-after-free in l2cap_conn_del() · 0d0e2d03
      Zhengchao Shao authored
      When l2cap_recv_frame() is invoked to receive data, and the cid is
      L2CAP_CID_A2MP, if the channel does not exist, it will create a channel.
      However, after a channel is created, the hold operation of the channel
      is not performed. In this case, the value of channel reference counting
      is 1. As a result, after hci_error_reset() is triggered, l2cap_conn_del()
      invokes the close hook function of A2MP to release the channel. Then
       l2cap_chan_unlock(chan) will trigger UAF issue.
      
      The process is as follows:
      Receive data:
      l2cap_data_channel()
          a2mp_channel_create()  --->channel ref is 2
          l2cap_chan_put()       --->channel ref is 1
      
      Triger event:
          hci_error_reset()
              hci_dev_do_close()
              ...
              l2cap_disconn_cfm()
                  l2cap_conn_del()
                      l2cap_chan_hold()    --->channel ref is 2
                      l2cap_chan_del()     --->channel ref is 1
                      a2mp_chan_close_cb() --->channel ref is 0, release channel
                      l2cap_chan_unlock()  --->UAF of channel
      
      The detailed Call Trace is as follows:
      BUG: KASAN: use-after-free in __mutex_unlock_slowpath+0xa6/0x5e0
      Read of size 8 at addr ffff8880160664b8 by task kworker/u11:1/7593
      Workqueue: hci0 hci_error_reset
      Call Trace:
       <TASK>
       dump_stack_lvl+0xcd/0x134
       print_report.cold+0x2ba/0x719
       kasan_report+0xb1/0x1e0
       kasan_check_range+0x140/0x190
       __mutex_unlock_slowpath+0xa6/0x5e0
       l2cap_conn_del+0x404/0x7b0
       l2cap_disconn_cfm+0x8c/0xc0
       hci_conn_hash_flush+0x11f/0x260
       hci_dev_close_sync+0x5f5/0x11f0
       hci_dev_do_close+0x2d/0x70
       hci_error_reset+0x9e/0x140
       process_one_work+0x98a/0x1620
       worker_thread+0x665/0x1080
       kthread+0x2e4/0x3a0
       ret_from_fork+0x1f/0x30
       </TASK>
      
      Allocated by task 7593:
       kasan_save_stack+0x1e/0x40
       __kasan_kmalloc+0xa9/0xd0
       l2cap_chan_create+0x40/0x930
       amp_mgr_create+0x96/0x990
       a2mp_channel_create+0x7d/0x150
       l2cap_recv_frame+0x51b8/0x9a70
       l2cap_recv_acldata+0xaa3/0xc00
       hci_rx_work+0x702/0x1220
       process_one_work+0x98a/0x1620
       worker_thread+0x665/0x1080
       kthread+0x2e4/0x3a0
       ret_from_fork+0x1f/0x30
      
      Freed by task 7593:
       kasan_save_stack+0x1e/0x40
       kasan_set_track+0x21/0x30
       kasan_set_free_info+0x20/0x30
       ____kasan_slab_free+0x167/0x1c0
       slab_free_freelist_hook+0x89/0x1c0
       kfree+0xe2/0x580
       l2cap_chan_put+0x22a/0x2d0
       l2cap_conn_del+0x3fc/0x7b0
       l2cap_disconn_cfm+0x8c/0xc0
       hci_conn_hash_flush+0x11f/0x260
       hci_dev_close_sync+0x5f5/0x11f0
       hci_dev_do_close+0x2d/0x70
       hci_error_reset+0x9e/0x140
       process_one_work+0x98a/0x1620
       worker_thread+0x665/0x1080
       kthread+0x2e4/0x3a0
       ret_from_fork+0x1f/0x30
      
      Last potentially related work creation:
       kasan_save_stack+0x1e/0x40
       __kasan_record_aux_stack+0xbe/0xd0
       call_rcu+0x99/0x740
       netlink_release+0xe6a/0x1cf0
       __sock_release+0xcd/0x280
       sock_close+0x18/0x20
       __fput+0x27c/0xa90
       task_work_run+0xdd/0x1a0
       exit_to_user_mode_prepare+0x23c/0x250
       syscall_exit_to_user_mode+0x19/0x50
       do_syscall_64+0x42/0x80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd
      
      Second to last potentially related work creation:
       kasan_save_stack+0x1e/0x40
       __kasan_record_aux_stack+0xbe/0xd0
       call_rcu+0x99/0x740
       netlink_release+0xe6a/0x1cf0
       __sock_release+0xcd/0x280
       sock_close+0x18/0x20
       __fput+0x27c/0xa90
       task_work_run+0xdd/0x1a0
       exit_to_user_mode_prepare+0x23c/0x250
       syscall_exit_to_user_mode+0x19/0x50
       do_syscall_64+0x42/0x80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd
      
      Fixes: d0be8347 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put")
      Signed-off-by: default avatarZhengchao Shao <shaozhengchao@huawei.com>
      Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
      0d0e2d03