• Stefan Wiehler's avatar
    of/irq: Prevent device address out-of-bounds read in interrupt map walk · b739dffa
    Stefan Wiehler authored
    When of_irq_parse_raw() is invoked with a device address smaller than
    the interrupt parent node (from #address-cells property), KASAN detects
    the following out-of-bounds read when populating the initial match table
    (dyndbg="func of_irq_parse_* +p"):
    
      OF: of_irq_parse_one: dev=/soc@0/picasso/watchdog, index=0
      OF:  parent=/soc@0/pci@878000000000/gpio0@17,0, intsize=2
      OF:  intspec=4
      OF: of_irq_parse_raw: ipar=/soc@0/pci@878000000000/gpio0@17,0, size=2
      OF:  -> addrsize=3
      ==================================================================
      BUG: KASAN: slab-out-of-bounds in of_irq_parse_raw+0x2b8/0x8d0
      Read of size 4 at addr ffffff81beca5608 by task bash/764
    
      CPU: 1 PID: 764 Comm: bash Tainted: G           O       6.1.67-484c613561-nokia_sm_arm64 #1
      Hardware name: Unknown Unknown Product/Unknown Product, BIOS 2023.01-12.24.03-dirty 01/01/2023
      Call trace:
       dump_backtrace+0xdc/0x130
       show_stack+0x1c/0x30
       dump_stack_lvl+0x6c/0x84
       print_report+0x150/0x448
       kasan_report+0x98/0x140
       __asan_load4+0x78/0xa0
       of_irq_parse_raw+0x2b8/0x8d0
       of_irq_parse_one+0x24c/0x270
       parse_interrupts+0xc0/0x120
       of_fwnode_add_links+0x100/0x2d0
       fw_devlink_parse_fwtree+0x64/0xc0
       device_add+0xb38/0xc30
       of_device_add+0x64/0x90
       of_platform_device_create_pdata+0xd0/0x170
       of_platform_bus_create+0x244/0x600
       of_platform_notify+0x1b0/0x254
       blocking_notifier_call_chain+0x9c/0xd0
       __of_changeset_entry_notify+0x1b8/0x230
       __of_changeset_apply_notify+0x54/0xe4
       of_overlay_fdt_apply+0xc04/0xd94
       ...
    
      The buggy address belongs to the object at ffffff81beca5600
       which belongs to the cache kmalloc-128 of size 128
      The buggy address is located 8 bytes inside of
       128-byte region [ffffff81beca5600, ffffff81beca5680)
    
      The buggy address belongs to the physical page:
      page:00000000230d3d03 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1beca4
      head:00000000230d3d03 order:1 compound_mapcount:0 compound_pincount:0
      flags: 0x8000000000010200(slab|head|zone=2)
      raw: 8000000000010200 0000000000000000 dead000000000122 ffffff810000c300
      raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
      page dumped because: kasan: bad access detected
    
      Memory state around the buggy address:
       ffffff81beca5500: 04 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
       ffffff81beca5580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
      >ffffff81beca5600: 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                            ^
       ffffff81beca5680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
       ffffff81beca5700: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
      ==================================================================
      OF:  -> got it !
    
    Prevent the out-of-bounds read by copying the device address into a
    buffer of sufficient size.
    Signed-off-by: default avatarStefan Wiehler <stefan.wiehler@nokia.com>
    Link: https://lore.kernel.org/r/20240812100652.3800963-1-stefan.wiehler@nokia.comSigned-off-by: default avatarRob Herring (Arm) <robh@kernel.org>
    b739dffa
irq.c 20.6 KB