this post was submitted on 15 May 2024
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I appreciate this thread's nuanced discussion of how file deletion works from a technical standpoint depending on storage medium. But as a user, when I delete something, it should go away forever. I don't care how.
grabs your phone, throws it on the ground and blasts it with a shotgun
There you go! =)
Cloud's deleted folder enters the chat.
Objective updated: shoot cloud server
Many years ago, we had a troubled employee leave work very mad. He was quite furious with his computer and went home for his revolver unbeknownst to us. He came back to work with it and unloaded all six rounds into the system. Each round went through the case and each one missed the drive/motherboard/videocard. So, the system was still working despite the abrupt extra cooling holes. This further incensed him and he went away even madder, but this time in cuffs.
Wow, how do you suck that bad at aiming?
It’s pretty easy if you don’t know where the computer’s vital organs are
You never shoot the ~~messenger~~ monitor.
The computer is good at dodging without moving
It’s like how I can talk while holding my breath but only over a call
John Connor has entered the chat
I’ve been pleased with their messaging on that - “deleted items remaining trash for [some period]…“ (IIRC)
Well… if you really want to delete them…
takes blasted phone, insert remnants into small iron cup, places in inductive furnace
Hey at least I know it gets the job done
Hmm. I don't know. Like, the actual surface involved in the storage is a lot smaller than the actual phone, and I imagine that you may-or-not destroy it with a given pellet.
I remember '80s movies -- from a time when a lot of people weren't all that personally-familiar with computers -- where someone "destroying a computer" consisted of shooting its screen, which might be not that far off what would be happening. here. In fact, I bet that that probably has a TV Tropes entry.
googles
Well, they have a guy punching it, same kind of idea.
https://tvtropes.org/pmwiki/pmwiki.php/Main/ComputerEqualsMonitor
Might be kind of the same idea, just writ small.
I’ve started seeing people, who really should know better, referring to the PC tower as the CPU. As in, “I bought a bracket that mounts to my variable height desk which can hold my CPU up off the floor and let it move with my desk”.
Bro I’m looking at a picture of a custom water cooled PC here, you should know the fucking difference between a CPU and a computer case.
Eh, that's been a thing for a long time. Decades at least.
I think that the problem is that there isn't really a great term to clearly refer to the "non-monitor-and-peripherals" part of the "computer". "Case" would refer to just the case, not what's in it. "Tower" or "desktop" is overspecific, refers to particular form factors. I have a tower, but some people have under-monitor desktops (though that's rare today) or various times of small form factor PCs. If I say "computer", that doesn't really clearly exclude peripherals.
And honestly, we don't really use the term "GPU" quite correctly either. I'll call a whole PCI video card a "GPU", but I suppose that strictly-speaking, that should only be talking about a specific chip on the card.
8 bit games would label the computer player as CPU as a shorthand, I honestly probably got snapped at by a nerd sometime in my teens for making the mistake and got the central processing unit lecture so I don’t really make that association but I also never heard anyone pronounce “NES” not as an acronym prior to YouTube, so, I figure different people have different experiences also.
At one time I remember people commonly referring to the case as the hard drive.
I learned everything about how to build a PC from buildapc... like 12 years ago. Nowadays it has been infested by idiots who don't know shit but act like they do, and also think more RGB = more better.
I don't know what happened, but I put together a PC for the first time in some years, and holy mother of God, all the components have RGB LEDs slapped on them now. I had to actively work to find parts that didn't have RGB LEDs on them (and I still accidentally wound up with some on the motherboard). I mean, yeah, LED case fans have been a thing for a while, and there was always a contingent that put electroluminescent strips on their computers. And it kinda grew into a lot of keyboards and mice. But now it's a large portion of CPU fans, most cases, RAM sticks have RGB LEDs, motherboards have RGB LEDs. I didn't have trouble finding non-RGB LED NVMe storage, or non-RGB LED SATA drives, but even there, you can get them. Hell, there are RGB LED cables.
I can only assume that a large portion of the people building PCs these days are doing it to have them physically blinged up.
Like, nothing wrong with wanting to do that, but I couldn't believe the tiny proportion that wasn't doing that.
I actually like having lights on the keyboard. Mostly because I can find rarely used keys in the dark.
The only way my box is blinged up is with tastefully beige-brown fans. I actually felt slightly betrayed by Noctua when they started making black fans.
You know what? They're technically correct. There's historically plenty of computer systems which came in multiple different cases, sometimes that's still the case but the most obvious examples are historical, where you would get something like the CPU (yes) in one case and then a huge-ass card reader in another case and drum memory in yet another. Those drums were used as RAM. Each case was standing on the floor, at least chest-high.
Simply integrating various peripherals into the CPU doesn't make the CPU any less of the CPU. Even ignoring the case thing and just looking at the CPU package (or even die): Modern CPUs contain a lot of things that would've been external to it, or even in a different case, in the past. You'll hear the term "SoC", system on a chip, thrown around but that's misleading most CPUs nowadays are SoCs: You have your CPU cores, yes, but you also have a memory controller, you have storage interfaces and general IO (PCIe is a storage interface), as well as a GPU. It's been a long time since mainboards came with northbridges. Newer CPUs may have enough memory on package to reasonably run without external memory (and not just "use the cache as ram during early boot" kind of stuff).
Easy peasy
Lemon squeezey
Years of working tech support in my past tells me that this is a lie. "OMG restore this!"
I think tech would be a better place if it did actually go away when you deleted things. If something's not explicitly backed up people really should have no hope of bringing it back.
If every time an OS had to delete something it had to fill the space with zeros or garbage data multiple times just to make extra sure it's gone, we'd all be trashing our flash chips very fast, and performance would be heavily degraded. There really isn't a way around this.
The solution to keep private files private is to put them into an encrypted container of some sort where you control the keys.
Step away from hardware constraints for a moment, and consider the OS:
If the OS says a file is deleted, under no circumstances should the OS be able to recover it. Sure, certain tools may exist to pull it back; but it should be unavailable to the OS after that. And yet, apparently a software update was enough to recover these files. Thus, the concerns about data safety in an environment where the OS cannot be trusted to remove data when it says it has been removed.
So let's stop calling it "deleted" then, and call it what it is. "Forgetting".
I'm not sure what you actually want the OS to do about it other than as I said, fill it with random data.
I think this is just semantics at this point, but to me there is a difference between “deleted” and “erased”. I see deleted as the typical “moved to trash” or
rmaction, with erased being overwritten bits, or like microwaving a drive.Edit - If i remember correctly deleting something in most OS’s/File Systems just deletes the pointer to that file on disk. The data just hangs out until new data is written to that sector. The solution, other than the one you mentioned about encrypting stored data and destroying the key when you want the data “deleted”, would be to only ever store data in volatile memory. That would make for a horrendous user experience though.
You can delete files by overwriting the data. On Linux its shred -zu [file]. Its slow but good to do if you are deleting sensitive data.
Its good its not the standard delete function.
Question: what fraction of bits do you need to randomly flip to ensure the data is unrecoverable?
Information theory aside: In practice all because you can't write bit-by-bit and if you leave full bytes untouched there still might be enough information for an attacker to get information, especially if it's of the "did this computer once store this file" kind of information, not the actual file contents.
If I'm not completely mistaken overwriting the file once will be enough to prevent recovering with logical means, that is, reading the bits the way the manufacturer intended you to, physical forensics can go further by being able to discern "this bit, before it got overwritten, was a 1 or 0" by looking very closely at the physical medium, details on how much flipping you need to defeat that will depend on the physical details.
And I wouldn't be too terribly sure about that electro magnet you built into your case to erase your HDD with a panic button: It's in a fixed place, will have a fixed magnetic field, it's going to scramble everything sure but the way it scrambles is highly uniform so the bits can probably be recovered. If you want to be really sure buy a crucible and melt the thing.
Also, may I interest you in this stylish tin-foil hat, special offer.
If you delete normally, only the index of the files are removed, so the data can be recovered by a recovery program reading the "empty" space on the disk and looking for readable data.
If you do a single pass erase, the bits will overwritten one time. About half the bits will be unchanged, but that makes little difference. Any recovery software trying to read it will read the newly written bits instead of the old ones and will not be able to recover anything.
However, forensic investigation can probably recover data after a single pass erase. The shred command defaults to 3 passes, but you can do many more if you need to be even more sure.
Unless you have data that someone would spend large sums on forensics to recover, 1 to 3 passes is probably enough.
If it's completely random then 50%, that's how stream ciphers works.
Well, iOS could just do it like every other OS that don't restore deleted data by installing an update.
Well, the storage device should handle that then. And modern NVMEs do. Self-encrypted drives are used to hide deleted information from an attacker that desolders the storage chips.
Edit: there are NVMEs that dont use self encryption, BUT they should still recognize a deleted sector.
That would apply in my "encrypted container of some sort" solution, yes.
Deletion commands are unfortunately not very reliable on many SSDs
The OS should never let that happen. It always should abstract the partition into a filesystem.
It's to prevent you from accidentally deleting a photo you would never want to delete. If you want to make sure it's deleted, you just go into the Photos app and delete it from the Recently Deleted folder. I prefer this approach, as I have accidentally deleted a photo that I did not mean to, and luckily it was still there. Use cases are different though, so.
That still doesn't fully erase the data though. It just tells the computer that that space on the drive is available to be overwritten, but the 1s and 0s are still recoverable
Right, right. I understand that. I was just explaining why the option is good for people like me. I don't take nudes, and I don't receive nudes, so I don't mind if the data is still there or not. I'm just glad the photo of me and my friend was still there when I noticed it was missing from my album after a recent meme deletion spree. lol
Imo there should be options for standard deletion and total deletion. Standard is faster, puts less wear on the drive, and keeps the files potentially recoverable, whole total would make it totally unrecoverable at the expense of taking slightly longer and putting a bit more wear on the drive
That is what thermite is for.
The second drive bay is the right size for a handy block of data erasing c4
No one will ever read my Zuck / Bezos fanfic.
Lol. I actually used to know a guy that claimed he used to have computer setup with a small thing to thermite on his hard drive and had set it up so if there were too many wrong passwords it would set the igniter off for the thermite. I don't know if you really, did but he definitely had the technical skills to do that. He was one of those extreme early adopters of BSD and Linux who never used GUI. Oh and he was batshit crazy, legitimately I can see him thinking that was a good idea.