2023-10-17 18:29:36 +00:00
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# ELF
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2023-10-18 15:03:31 +00:00
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## Basic structure
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2023-10-17 18:29:36 +00:00
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2023-10-18 15:03:31 +00:00
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1. ELF header (0x00 - 0x40)
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2. Program header (0x40 - 0x78)
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3. Padding (0x78 - 0x80)
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4. Machine code (0x80)
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2023-10-17 18:29:36 +00:00
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## Entry point
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The entry point is defined in the first 64 bytes (ELF header).
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2023-10-18 15:03:31 +00:00
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## Base address
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The minimum base address is controlled by the `mmap` settings:
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```shell
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sysctl vm.mmap_min_addr
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```
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Usually, this value is 65536 (0x1000).
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## Initialization in Linux
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See `/lib/modules/$(uname -r)/build/arch/x86/include/asm/elf.h`.
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