Dobin 0x11_MemoryLayout.pdf
Dobin 0x11_MemoryLayout.pdf
Dobin 0x11_MemoryLayout.pdf
Describe the memory layout of a 32 bit system inluding the EIP and ESP pointer.
What are the charecteristics of the stack?
Stack:
- There is one contiguous memory region containing the stack for the process
- LIFO - Last in, First Out
- Contains funtion local variables
- Also contains: Saved Instruction Pointer (SIP)
- Current function adds data to the top (bottom) of the stack
What are the charecteristics of the heap?
Heap:
- There is on contiguous memory region containing the heap
- Memory allocator returns specific pieces of the memory region
- For malloc()
- Alos contains: heap management data
What is stored in the code region in memory?
Code region contains:
- Compiled program code
What is the ELF format, and name 3 types.
Programs are stored in ELF files
ELF: Executable and Linkable Format
- Like COFF, PE (EXE), ....
ELF types:
- ET_EXEC: Executable File
- ET_REL: Relocatable File
- ET_DYN: Shared Object File
ELF "views"
- Sections
- Segments
Describe the ELF Format how is it structured?
Sturcture of ELF file from top to bottom:
- ELF Header
- Program Header Table (contains the location of sections)
- Sections (are contained in segments)
- Section Header Table (contains locationn of sections
In the ELF format what can be contained in the sections?
Sections:
- .text: Executable instructions
- .bss: Unitialized data (usualy the heap)
- .data: initialized data
- .rodata: Read-Only data
- .got: Global Offset Table
- .plt: Prcedure Linkage Table
- .init / .fini: initialiyation instructions ("glibc")
How is an ELF file loaded what is loaded into the stack, heap and code block?
.plt, .text, .init get written into code block
.got, .data, .bss is written into the heap
unalocated space is the stack.
What is the process of creating a process from an ELF file called and what are the sections and segments used for?
The process of creating a process from an ELF file is called: "Linking and Loading"
Sections:
- Are for compiler (gcc), to link several objec t files together (.o)
Segments:
- Are for the loader, to create the process
- Consists of one or more sections
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Cartes-fiches
Describe the memory layout of a 32 bit system inluding the EIP and ESP pointer.
What are the charecteristics of the stack?
Stack:
- There is one contiguous memory region containing the stack for the process
- LIFO - Last in, First Out
- Contains funtion local variables
- Also contains: Saved Instruction Pointer (SIP)
- Current function adds data to the top (bottom) of the stack
What are the charecteristics of the heap?
Heap:
- There is on contiguous memory region containing the heap
- Memory allocator returns specific pieces of the memory region
- For malloc()
- Alos contains: heap management data
What is stored in the code region in memory?
Code region contains:
- Compiled program code
What is the ELF format, and name 3 types.
Programs are stored in ELF files
ELF: Executable and Linkable Format
- Like COFF, PE (EXE), ....
ELF types:
- ET_EXEC: Executable File
- ET_REL: Relocatable File
- ET_DYN: Shared Object File
ELF "views"
- Sections
- Segments
Describe the ELF Format how is it structured?
Sturcture of ELF file from top to bottom:
- ELF Header
- Program Header Table (contains the location of sections)
- Sections (are contained in segments)
- Section Header Table (contains locationn of sections
In the ELF format what can be contained in the sections?
Sections:
- .text: Executable instructions
- .bss: Unitialized data (usualy the heap)
- .data: initialized data
- .rodata: Read-Only data
- .got: Global Offset Table
- .plt: Prcedure Linkage Table
- .init / .fini: initialiyation instructions ("glibc")
How is an ELF file loaded what is loaded into the stack, heap and code block?
.plt, .text, .init get written into code block
.got, .data, .bss is written into the heap
unalocated space is the stack.
What is the process of creating a process from an ELF file called and what are the sections and segments used for?
The process of creating a process from an ELF file is called: "Linking and Loading"
Sections:
- Are for compiler (gcc), to link several objec t files together (.o)
Segments:
- Are for the loader, to create the process
- Consists of one or more sections
