2018-01-30 03:41:02 +00:00
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/*
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* Copyright (c) 2018 William Pitcock <nenolod@dereferenced.org>
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*
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* Permission to use, copy, modify, and/or distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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*
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* This software is provided 'as is' and without any warranty, express or
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* implied. In no event shall the authors be liable for any damages arising
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* from the use of this software.
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*/
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.globl __start_context;
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__start_context:
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/* get the proper context into position and test for NULL */
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movq %rbx, %rsp
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movq (%rsp), %rdi
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testq %rdi, %rdi
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2018-02-15 04:34:37 +00:00
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/* if we have no linked context, lets get out of here */
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je no_linked_context
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2018-01-30 03:41:02 +00:00
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/* call setcontext to switch to the linked context */
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call __setcontext@plt
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movq %rax, %rdi
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2018-02-15 04:34:37 +00:00
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no_linked_context:
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2018-01-30 03:41:02 +00:00
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/* we are returning into a null context, it seems, so maybe we should exit */
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call exit@plt
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/* something is really hosed, call hlt to force termination */
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hlt
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