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.hatay...@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); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/