Commit 1c938663 authored Jun 11, 2010 by Krzysztof Halasa Committed by Michal Marek Jun 12, 2010

kbuild: Fix modpost segfault



Alan <alan@clueserver.org> writes:

> program: /home/alan/GitTrees/linux-2.6-mid-ref/scripts/mod/modpost -o
> Module.symvers -S vmlinux.o
>
> Program received signal SIGSEGV, Segmentation fault.

It just hit me.
It's the offset calculation in reloc_location() which overflows:
        return (void *)elf->hdr + sechdrs[section].sh_offset +
               (r->r_offset - sechdrs[section].sh_addr);

E.g. for the first rodata r entry:
r->r_offset < sechdrs[section].sh_addr
and the expression in the parenthesis produces 0xFFFFFFE0 or something
equally wise.

Reported-by: Alan <alan@clueserver.org>
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
Tested-by: Alan <alan@clueserver.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>

parent 607b30fc

scripts/mod/modpost.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1342,7 +1342,7 @@ static unsigned int reloc_location(struct elf_info elf,
		int section = sechdr->sh_info;

		return (void *)elf->hdr + sechdrs[section].sh_offset +
		(r->r_offset - sechdrs[section].sh_addr);
		r->r_offset - sechdrs[section].sh_addr;
		}

		static int addend_386_rel(struct elf_info elf, Elf_Shdr sechdr, Elf_Rela *r)

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