errors from rn_inithead back to the ipfw initialization function.
- Check return value of rn_inithead for failure, if table allocation has
failed for any reason, free up any tables we have created and return ENOMEM
- In ipfw_init check the return value of init_tables and free up any mutexes or
UMA zones which may have been created.
- Assert that the supplied table is not NULL before attempting to dereference.
This fixes panics which were a result of invalid memory accesses due to failed
table allocation. This is an issue mainly because the R_Zalloc function is a
malloc(M_NOWAIT) wrapper, thus making it possible for allocations to fail.
Found by: Coverity Prevent (tm)
Coverity ID: CID79
MFC after: 1 week
9c57c204be