Changes

Kernel Loader (view source)

863 bytes added , 04:26, 31 August 2019

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== KernelLdr_ApplyRelocations ==

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~~TODO~~: ~~Fill this out~~

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This does standard ELF relocation using .dynamic.

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First, it iterates over all entries in .dynamic, extracting .rel.dyn, .rela.dyn, relent, relatent, relcount, relacount from the relevant entries.

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Then it does the following two loops to apply R_AARCH64_RELATIVE relocations:

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<pre>

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for (size_t i = 0; i < rel_count; i++) {

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const Elf64_Rel *rel = dyn_rel_start + rel_ent * i;

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while (uint32_t(rel->r_info) != R_AARCH64_RELATIVE) { /* Invalid entry, infloops */ }

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*((Elf64_Addr *)(base_address + rel->r_offset)) += base_address;

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}

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</pre>

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<pre>

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for (size_t i = 0; i < rela_count; i++) {

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const Elf64_Rela *rela = dyn_rela_start + rela_ent * i;

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while (uint32_t(rela->r_info) != R_AARCH64_RELATIVE) { /* Invalid entry, infloops */ }

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*((Elf64_Addr *)(base_address + rela->r_offset)) = base_address + rela->r_addend;

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}

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</pre>

== KernelLdr_lib_init_array() ==

888

edits