always make a process snapshot as the kernel might discard your broken process once it runs low on memory so you have time to debug:
snap 41356 >/tmp/dns.snap char *domain strings alloc header seems to have been corrupted (or just freed by accident?). the string just gets allocated and freed in mydnsquery() so its unlikely a bug there. someone else has corrupted its alloc header? it looks more like corruption as we dont hand this pointer out to someone else but netmkaddr(). look at the raw data, often one can get a clue by what it got overridden with and try to figure out what the previous block before our block that got corrupted was. the pool allocator keeps the callerpc's of who allocated the block so you can use that to figure out what it is, or look at the contents. // dump the memory arround our corrupted block dump(0x497f8 - 0x10, 0x100, "X") maybe our block didnt got overridden but really freed with a call to free but with the wrong pointer? check the alloc magic! // check the contents, should be an ip address string dump(0x49800, 1, "s") run acid with -lpool -lleak and run blockdump() if its corrupted block, it might just stop at the block before our one and will print the allocpc's and give some diagnostics. i can try this if you provide process snapshot file. -- cinap
