lkml.org 
[lkml]   [2010]   [Jun]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    SubjectRe: Additional info on modpost segfault
    Date
    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.

    Does the attached patch fix it?

    Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>

    --- a/scripts/mod/modpost.c
    +++ b/scripts/mod/modpost.c
    @@ -1317,8 +1317,8 @@ static unsigned int *reloc_location(struct elf_info *elf,
    Elf_Shdr *sechdrs = elf->sechdrs;
    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)
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/
    \
     
     \ /
      Last update: 2010-06-11 01:11    [W:0.019 / U:62.068 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site