• Pierre-Louis Bossart's avatar
    ACPI / property: fix handling of data_nodes in acpi_get_next_subnode() · 23583f77
    Pierre-Louis Bossart authored
    When the DSDT tables expose devices with subdevices and a set of
    hierarchical _DSD properties, the data returned by
    acpi_get_next_subnode() is incorrect, with the results suggesting a bad
    pointer assignment. The parser works fine with device_nodes or
    data_nodes, but not with a combination of the two.
    
    The problem is traced to an invalid pointer used when jumping from
    handling device_nodes to data nodes. The existing code looks for data
    nodes below the last subdevice found instead of the common root. Fix
    by forcing the acpi_device pointer to be derived from the same fwnode
    for the two types of subnodes.
    
    This same problem of handling device and data nodes was already fixed
    in a similar way by 'commit bf4703fd ("ACPI / property: fix data
    node parsing in acpi_get_next_subnode()")' but broken later by 'commit
    34055190 ("ACPI / property: Add fwnode_get_next_child_node()")', so
    this should probably go to linux-stable all the way to 4.12
    Signed-off-by: default avatarPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
    Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    23583f77
property.c 35.7 KB