Re: [PATCH v2 03/20] vmcore, sysfs: export ELF note segment size instead of vmcoreinfo data size

Zhang Yanfei
2013-03-05T09:31:07Z

于 2013年03月02日 16:36, HATAYAMA Daisuke 写道:
> p_memsz member of program header entry with PT_NOTE type needs to have
> size of the corresponding ELF note segment. Currently, vmcoreinfo
> exports data part only. If vmcoreinfo reachs vmcoreinfo_max_size, then
> in merge_note_headers_elf{32,64}, empty ELF note header cannot be
> found or buffer overrun can happen.
>
> Note: kexec-tools assigns PAGE_SIZE to p_memsz for other ELF note
> types. Due to the above reason, the same issue occurs if actual ELF
> note data exceeds (PAGE_SIZE - 2 * KEXEC_NOTE_HEAD_BYTES).
>
> Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
> ---
>
> kernel/ksysfs.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
> index 6ada93c..97d2763 100644
> --- a/kernel/ksysfs.c
> +++ b/kernel/ksysfs.c
> @@ -126,7 +126,7 @@ static ssize_t vmcoreinfo_show(struct kobject *kobj,
> {
> return sprintf(buf, "%lx %x\n",
> paddr_vmcoreinfo_note(),
> - (unsigned int)vmcoreinfo_max_size);
> + (unsigned int)sizeof(vmcoreinfo_note));
> }
> KERNEL_ATTR_RO(vmcoreinfo);

Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>

>
>
>
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec
>