Overflow Memory with Network Update??

Discuss the development of new homebrew software, tools and libraries.

Moderators: cheriff, TyRaNiD

Post Reply
RATiX
Posts: 48
Joined: Sat Apr 30, 2005 5:02 pm

Overflow Memory with Network Update??

Post by RATiX »

When you download an update with the Network Update function, it doesn't write the file to the memory stick until the very end. For example, if you start a Network Update, rip the MS out ater it has started downloading (I did this when it was at 0%), all you get is a file that says "Corrupted Data" and supposedly 16KB big under the Game -> Memory Stick place in the XMB. I run Network update again, let it d/l 99% of the update, and I rip the MS out. Again, I get a 16 KB "Corrupted Data" file. Basically, if someone was able to use the Network Update function to send it a homebrew update with a large file size, you would be able to overrun the memory (which seems to be the place where the update file is stored until it's 100% downloaded).

Also, if you have an update (100%, non-corrupted) on the MS, and re-download the update, if you let it d/l 100% of the way, it will overwrite the update on the MS.

My guess is that the Network Update sends some 16KB file to reserve space (or maybe act as some kind of header or container) for the update. The update downloads, but not to the Memory Stick, despite the fact that the Memory Stick access light flashes constantly. Perhaps some small bit of data is being while the update is being d/l'd. Anyway, after all files have been downloaded, the PSP checks if there has been another update on the MS (or perhaps it does this when it first creates the 16KB file, I don't know) and then overwrites any existing update with the one stored in memory.

I don't know if a memory overflow is useful, but this is one way to do it, or so it seems.

*I haven't connected the PSP to a PC to see what the real size of the "Corrupted Data" files are; they may be smaller/larger than 16KB in reality.
mrbrown
Site Admin
Posts: 1537
Joined: Sat Jan 17, 2004 11:24 am

Post by mrbrown »

Moved to the new Exploit forum.

Dude, news for you, it is writing to the memory stick, that's why the light is constantly flashing. But because you eject it while it's writing, it never gets the chance to close the file, resulting in corrupted data.

You can end up trashing your memory stick this way, I wouldn't advise doing it anymore. I think Herben mentioned this in another thread, but folks, please don't yank out your memory stick as it's being accessed, that's just being dumb.
ichan
Posts: 7
Joined: Sun Apr 03, 2005 1:28 am

Post by ichan »

just something really simple i've always wanted to know, does yanking out a memory stick actually thrash it to an unrecoverable state potentially or would it just corrupt the data and require a re-formatting?
zigzag
Posts: 129
Joined: Wed Jan 26, 2005 2:11 pm

Post by zigzag »

I heard the PSP doesn't have enough memory for a memory overflow exploit? Is this the case?

lol... sorry, I couldn't resist :)
pixel
Posts: 791
Joined: Fri Jan 30, 2004 11:43 pm

Post by pixel »

Troll radar detection alert!
pixel: A mischievous magical spirit associated with screen displays. The computer industry has frequently borrowed from mythology. Witness the sprites in computer graphics, the demons in artificial intelligence and the trolls in the marketing department.
quedijo
Posts: 3
Joined: Fri May 20, 2005 2:45 pm
Location: Earth

Post by quedijo »

ROFLOL... your retarded zigzag. :P ;)
`^~${NONO}$~^`
"it's Not Joey, It's Noe!"
allthatinny
Posts: 24
Joined: Fri May 06, 2005 5:59 pm

Post by allthatinny »

why is he retarted, cuz he dont know as much as you do?
allthatinny
Posts: 24
Joined: Fri May 06, 2005 5:59 pm

Post by allthatinny »

zigzag wrote:I heard the PSP doesn't have enough memory for a memory overflow exploit? Is this the case?

lol... sorry, I couldn't resist :)
ack didnt notice that last bit at the bottom, my bad ;)
Post Reply