Questions tagged [virtual-memory]

In computing, virtual memory is a memory management technique developed for multitasking kernels. This technique virtualizes a computer architecture's various forms of computer data storage (such as random-access memory and disk storage), allowing a program to be designed as though there is only one kind of memory, "virtual" memory, which behaves like directly addressable read/write memory (RAM).

In computing, virtual memory is a memory management technique developed for multitasking kernels. This technique virtualizes a computer architecture's various forms of computer data storage (such as random-access memory and disk storage), allowing a program to be designed as though there is only one kind of memory, "virtual" memory, which behaves like directly addressable read/write memory (RAM).

-- Wikipedia

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Why encrypt data in memory?

I saw that KeePass not only encrypts its password-database-file, it also can encrypt the passwords it holds in memory. This is just an example. I thinking of a new project dealing with sensitve / personal data and now I ask myself if I should…
user573215
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Reading physical memory frame previously owned by another process to read contents of its memory page

I had a conversation with @anger32 who states that zeroing a physical memory page frame when passing the page backed by that frame to another process is not the responsibility of OSes like Windows and Linux (though they do that, they don't guarantee…
KOLANICH
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Ring 1 and Ring 2 Memory Protection Architecture

I have heard that Ring 1 and Ring 2 memory protections are basically no-longer used within modern systems. However, when I checked into things, all I found was that these rings are somehow associated with drivers and driver access. Have these really…
Guy Incognito
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Effects of DDoS attacks on memory use under Linux

Can someone whose Linux system is under DDoS attacks give me exact data on the effects of the Low Orbit Ion Cannon (LOIC), the High Orbit Ion Cannon (HOIC), Slowloris, PyLoris, Hping etc. on memory use under Linux? Basically, I'd like timestamped…
nlovric
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Does Linux kernel use DEP for kernel memory?

Does the Linux kernel use DEP internally for its kernel memory? In other words, does the Linux kernel take care to ensure that, when the kernel is executing (in kernel mode), every executable location in memory is non-writeable, and every writeable…
D.W.
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RAM Encryption. Is it possible?

Without adding any additional hardware, is RAM encryption possible? If so are there any known and currently used implementations for Linux or Windows systems? And if this is something that is possible without extra hardware, is there any software…
16b7195abb140a3929bbc322d1c6f1
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How to securely read a physical memory address in Linux?

I am trying to read a physical memory address in a device running embedded Linux with our application. The widely suggested method is to use mmap , convert it into virtual address and then read the value. Now I would like to know if it a man in the…
Vasu
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Is the Windows paging file safe in the encrypted partition?

I came across this setting called ClearPageFileAtShutdown. The setting is described here and says: If you are truly worried about security, boot Windows off a fully-encrypted drive. Then you needn't worry about your sensitive data being unencrypted…
Iteration
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Heartbleed and heap management - Why user data and passwords are kept in memory?

If I understand correctly the hearbleed vulnerability, only the heap of the OpenSSL process can be retrieved by an attacker (or part of depending on the memory allocation type that is used). Then, how comes the OpenSSL process keeps in memory what…
ack__
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How to detect when your RAM is being copied or scanned by a hypervisor

I am working in a Virtual Machine that is on a ESXi server on a remote machine. I am not the only one who has access to the ESXi and others could take memory snapshots of my running VM. Is there a way to detect someone trying to take a snapshot, or…
user3779430
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Shutdown: Clear virtual memory pagefile

I was reading about Windows Local Policy of " Shutdown: Clear virtual memory pagefile ". I need some clarification on this brief policy description: What do it mean by operating system that allow booting to the other. Why OS has to make sure that…
Ali Ahmad
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Intepreting PE (Portable Executable) headers of suspicious malware files

I am starting up on malware analysis, and I am analyzing a file to see if it is packed or obfuscated. Using PEview I am examining the .text, .rdata and .data headers. I know that if there is a big difference between the Virtual Size (size…
Franko
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Why code memory pages should be readable?

I understand that each instruction should be read into CPU for execution, which probably is the reason why code pages should be "r-x". But my observation is that the behavior of reading code into CPU for execution is normal, while reading code into…
Infinite
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Completely Protected Virtual Folder

I am a Python / C developer currently working on a extremely important piece of software. The details of the code will not be mentioned, and the only place the code appears is on my own hard drive, in a virtual disk image used by a windows 7 virtual…
joebloggs
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PGP on hibernation files?

I was afraid reading this: This $299 tool is reportedly capable of decrypting BitLocker, PGP, and TrueCrypt disks in real-time . It seems to me that PGP and other sensible tools have to lock memory to ensure they where not be swapped, nor…
F. Hauri - Give Up GitHub
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