chrisrohlf | 2 years ago | on: Remembering Bell Labs as legendary idea factory prepares to leave N.J. home
chrisrohlf's comments
chrisrohlf | 2 years ago | on: The last days of a 350-year-old family farm
chrisrohlf | 2 years ago | on: The last days of a 350-year-old family farm
This is exactly what it is here in NJ. They’re called ‘fake farmers’ here, and a quick google search will show you they cost the state tens of millions in lost tax revenue per year. Its all the usual suspects too, you know, the kind of celebrities that lecture you on giving and their politics. Those quaint farm stands are just a ruse to keep their tax bills to a minimum on >5 acres if expensive land in wealthy counties.
chrisrohlf | 3 years ago | on: Netflix to open $900M facility at former Fort Monmouth Army base in New Jersey
chrisrohlf | 3 years ago | on: Netflix to open $900M facility at former Fort Monmouth Army base in New Jersey
https://tworivertimes.com/move-over-netflix-the-army-signal-...
chrisrohlf | 3 years ago | on: How secure are RISC-V chips?
chrisrohlf | 3 years ago | on: The era of fast, cheap genome sequencing is here
I’ve yet to finish the order process but I share this here because in my research of companies providing full sequencing services I never came across them and yet they seem far more reputable than others. Current SEO for these services turns up a lot of sketchy companies.
chrisrohlf | 4 years ago | on: AI Code Generation and Cybersecurity
It’s a really exciting area of research.
chrisrohlf | 5 years ago | on: IsoAlloc: Detecting Uninitialized Reads with Userfaultfd
chrisrohlf | 5 years ago | on: IsoAlloc: Detecting Uninitialized Reads with Userfaultfd
chrisrohlf | 5 years ago | on: IsoAlloc: Detecting Uninitialized Reads with Userfaultfd
chrisrohlf | 6 years ago | on: Isolation Alloc
You're right that Electric Fence takes a different approach and is more geared towards finding bugs and isn't really suitable as a general purpose allocator. The easiest way to describe it is taking some allocations and placing them on their own page of memory, surrounding them with guard pages, and then setting the page PROT_NONE upon free so that any access results in a segfault. For a more modern attempt at this check out GWP ASAN which is doing something very similar but in Chrome across millions of installs https://chromium.googlesource.com/chromium/src.git/+/master/...
As for the allocator in glibc, a lot of its internal data structures either live on the same pages as user chunks or write meta data to free chunks. So using aggressive strategies like page permissions to protect that data is often not an option.
chrisrohlf | 7 years ago | on: On exploiting the jemalloc memory manager (2014)
chrisrohlf | 7 years ago | on: Ask HN: How do security researchers know where to look for vulnerabilites?
chrisrohlf | 9 years ago | on: Ask HN: How do I start my own consulting firm?
chrisrohlf | 9 years ago | on: Ask HN: How do I start my own consulting firm?
1) Your tech skills matter less than you think they do. Customers want good work of course but they also need a reliable partner who will answer the phone and provide guidance beyond just handing over code or a report. Be professional above all else.
2) Don't fool yourself that you're only consulting while you build a product. Its two entirely separate types of businesses. If you try to do both you run the risk of doing them both poorly.
3) Figure out your growth plan before even thinking about a sales person. You probably wont need one for awhile.
4) Yes you want mentors, preferably people who have built something similar to what you're trying to build now. Even better if they failed at it.
5) Don't rush into subcontracting. You will lock yourself out of big contracts that way. Large companies want a varied list of vendors to choose from. Only do this when it makes strategic sense for your longer term plans.
A small consultancy is a great lifestyle business. Be realistic about your goals for it. Scaling up a consultancy is mostly limited by how many experts you can hire. And if you do your job right its only a matter of time before your best people start their own thing.
chrisrohlf | 9 years ago | on: Ask HN: Who is hiring? (June 2016)
You can find all of our openings here https://tas-yahoo.taleo.net/careersection/yahoo_us_cs/jobsea...
chrisrohlf | 10 years ago | on: Font Parsing Vulnerabilities
chrisrohlf | 10 years ago | on: Rtrace is an x86/x86_64 native code debugger written in Ruby
I wrote Eucalyptus as the primary unit test for rtrace but its a fully functional native code debugger. Here is an example of how you can configure it using Ruby to trace calls to malloc() and print out some information:
https://github.com/yahoo/rtrace/blob/master/Eucalyptus/examp...
If you're interested in contributing, the signal handler in Rtrace could use some cleanup. Helper methods for interacting with procfs and the process memory are always useful too.
chrisrohlf | 11 years ago | on: Improving browser security