segfault due to dereference near-null pointer in do_refill

[kcwu]

input

00000000: 3c74 6162 6c65 3e3c 6c69 7374 696e 673e  <table><listing>
00000010: 3c74 6162 6c65 5f61 6c74 2074 6964 3d30  <table_alt tid=0
00000020: 3c2f 6c69 7374 696e 673c 7461 626c 653e  </listing<table>

gdb

Program received signal SIGSEGV, Segmentation fault.
0x00000000004423a4 in do_refill (tbl=0x7bf000, row=0, col=0, maxlimit=79) at table.c:768
768                     int limit = tbl->tables[id].indent + t->total_width;
(gdb) p t
$1 = (struct table *) 0x0

found by afl-fuzz

[tats]

Fixed, thank you.