Description of problem:

struct dqblk
  {
    u_int32_t dqb_bhardlimit;   /* absolute limit on disk blks alloc */
    u_int32_t dqb_bsoftlimit;   /* preferred limit on disk blks */
    u_int32_t dqb_curblocks;    /* current block count */
    u_int32_t dqb_ihardlimit;   /* maximum # allocated inodes */
    u_int32_t dqb_isoftlimit;   /* preferred inode limit */
    u_int32_t dqb_curinodes;    /* current # allocated inodes */
    time_t dqb_btime;           /* time limit for excessive disk use */
    time_t dqb_itime;           /* time limit for excessive files */
  };

struct rquota {
        int rq_bsize;
        bool_t rq_active;
        u_int rq_bhardlimit;
        u_int rq_bsoftlimit;
        u_int rq_curblocks;
        u_int rq_fhardlimit;
        u_int rq_fsoftlimit;
        u_int rq_curfiles;
        u_int rq_btimeleft;
        u_int rq_ftimeleft;
};

rquota_server.c line 171 has the following memcpy:

memcpy((caddr_t *)&result.getquota_rslt_u.gqr_rquota.rq_bhardlimit,
                (caddr_t *)&dq_dqb, sizeof(struct dqblk));
                                                                     
                                                     
the goal of the memcpy is to copy the 8 fields from struct dqblk to 
the last 8 fields of the struct quota.
That is, 6 ints and 2 time_t's get copied to 8 ints.
On 32 bit machines, that's ok (but ugly) since a time_t is also a 32
bit value; on 64 bit machines time_t is 64 bit though, thus buffer
overflowing the stack.

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