Bad sh_off or sh_size could trigger a bad malloc or read. Sanity check
the header values first before trying to malloc a huge buffer or reading
any data that will certainly fail.
https://bugzilla.redhat.com/show_bug.cgi?id=1387584
Signed-off-by: Mark Wielaard <mjw@redhat.com>
+2016-10-21 Mark Wielaard <mjw@redhat.com>
+
+ * elf_getdata.c (__libelf_set_rawdata_wrlock): Sanity check
+ offset and size before trying to malloc and read data.
+
2016-10-26 Mark Wielaard <mjw@redhat.com>
* elf_begin.c (read_file): Always set maxsize when parent == NULL.
}
else if (likely (elf->fildes != -1))
{
+ /* First see whether the information in the section header is
+ valid and it does not ask for too much. Check for unsigned
+ overflow. */
+ if (unlikely (offset > elf->maximum_size
+ || elf->maximum_size - offset < size))
+ {
+ /* Something is wrong. */
+ __libelf_seterrno (ELF_E_INVALID_SECTION_HEADER);
+ return 1;
+ }
+
/* We have to read the data from the file. Allocate the needed
memory. */
scn->rawdata_base = scn->rawdata.d.d_buf