• mckusick's avatar
    The binary representation of the superblock (the fs structure) is written · cfac6b7d
    mckusick authored
    out verbatim to the disk: see ffs_sbput() in sys/ufs/ffs/ffs_subr.c.
    It contains a pointer to the fs_summary_info structure. This pointer
    value inadvertently causes garbage to be stored. It is garbage because
    the pointer to the fs_summary_info structure is the address the then
    current stack or heap. Although a mere pointer does not reveal anything
    useful (like a part of a private key) to an attacker, garbage output
    deteriorates reproducibility.
    
    This commit zeros out the pointer to the fs_summary_info structure
    before writing the out the superblock.
    
    Reviewed by:  kib
    Tested by:    Peter Holm
    PR:           246983
    Sponsored by: Netflix
    cfac6b7d