debugedit: fix segment fault while file's bss offset have a large number

While ELF_C_RDWR_MMAP was used, elf_begin invoked mmap() to map file
into memory. While the file's bss Offset has a large number, elf_update
caculated file size by __elf64_updatenull_wrlock and the size was
enlarged.

In this situation, elf_update invoked ftruncate to enlarge the file,
and memory size (elf->maximum_size) also was incorrectly updated.
There was segment fault in elf_end which invoked munmap with the
length is the enlarged file size, not the mmap's length.

Before the above operations, invoke elf_begin/elf_update/elf_end
with ELF_C_RDWR and ELF_F_LAYOUT set to enlarge the above file, it
could make sure the file is safe for the following elf operations.

[YOCTO #5356]
https://bugzilla.redhat.com/show_bug.cgi?id=1019707
https://bugzilla.redhat.com/show_bug.cgi?id=1020842

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>

0 files changed, 0 insertions, 0 deletions