tftp: prevent overwriting reserved memory

This fixes CVE-2018-18439 ("insufficient boundary checks in network
image boot") by using lmb to check for a valid range to store
received blocks.

Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
[trini: Always build lib/lmb.o on LMB and lib/fdtdec.o on OF_LIBFDT]
Signed-off-by: Tom Rini <trini@konsulko.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/Makefile b/lib/Makefile
index f5de4a851b..61d7ff0678 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -30,14 +30,12 @@ obj-y += crc7.o
 obj-y += crc8.o
 obj-y += crc16.o
 obj-$(CONFIG_ERRNO_STR) += errno_str.o
-obj-$(CONFIG_OF_LIBFDT) += fdtdec.o
 obj-$(CONFIG_FIT) += fdtdec_common.o
 obj-$(CONFIG_TEST_FDTDEC) += fdtdec_test.o
 obj-$(CONFIG_GZIP_COMPRESSED) += gzip.o
 obj-$(CONFIG_GENERATE_SMBIOS_TABLE) += smbios.o
 obj-$(CONFIG_IMAGE_SPARSE) += image-sparse.o
 obj-y += initcall.o
-obj-$(CONFIG_LMB) += lmb.o
 obj-y += ldiv.o
 obj-$(CONFIG_MD5) += md5.o
 obj-y += net_utils.o
@@ -89,9 +87,11 @@ obj-y += crc32.o
 obj-$(CONFIG_CRC32C) += crc32c.o
 obj-y += ctype.o
 obj-y += div64.o
+obj-$(CONFIG_OF_LIBFDT) += fdtdec.o
 obj-y += hang.o
 obj-y += linux_compat.o
 obj-y += linux_string.o
+obj-$(CONFIG_LMB) += lmb.o
 obj-y += membuff.o
 obj-$(CONFIG_REGEX) += slre.o
 obj-y += string.o