x86, relocs: Add more per-cpu gold special cases (d751c169) · Commits · 戴 / test

The "gold" linker doesn't seem to put some additional per-cpu cases in the right place. Add these to the per-cpu check. Without this, the kASLR patch series fails to correctly apply relocations, and fails to boot. Signed-off-by:

Michael Davidson <md@google.com> Signed-off-by:

Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/20131011013954.GA28902@www.outflux.net Signed-off-by:

H. Peter Anvin <hpa@linux.intel.com>

arch/x86/tools/relocs.c

+13 −5

Original line number	Diff line number	Diff line
		@@ -722,15 +722,23 @@ static void percpu_init(void)

		/*
		* Check to see if a symbol lies in the .data..percpu section.
		* For some as yet not understood reason the "__init_begin"
		* symbol which immediately preceeds the .data..percpu section
		* also shows up as it it were part of it so we do an explict
		* check for that symbol name and ignore it.
		*
		* The linker incorrectly associates some symbols with the
		* .data..percpu section so we also need to check the symbol
		* name to make sure that we classify the symbol correctly.
		*
		* The GNU linker incorrectly associates:
		* __init_begin
		*
		* The "gold" linker incorrectly associates:
		* init_per_cpu__irq_stack_union
		* init_per_cpu__gdt_page
		*/
		static int is_percpu_sym(ElfW(Sym) sym, const char symname)
		{
		return (sym->st_shndx == per_cpu_shndx) &&
		strcmp(symname, "__init_begin");
		strcmp(symname, "__init_begin") &&
		strncmp(symname, "init_per_cpu_", 13);
		}

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