Am 17.12.2018 um 20:06 schrieb Simon Goldschmidt:
This series fixes CVE-2018-18440 ("insufficient boundary checks in filesystem image load") by adding restrictions to the 'load' command and fixes CVE-2018-18439 ("insufficient boundary checks in network image boot") by adding restrictions to the tftp code. The functions from lmb.c are used to setup regions of allowed and reserved memory. Then, the file size to load is checked against these addresses and loading the file is aborted if it would overwrite reserved memory.
The memory reservation code is reused from bootm/image.
Changes in v7:
- add braces around if/else with macros accross more than one line
- fix compiling without CONFIG_FIT
- fix compiling without CONFIG_LMB
Please ignore v7: I've just found an overflow bug in the ARM port of 'arch_lmb_reserve' that should go in as well. I'm preparing v8.
Regards, Simon
Changes in v6:
- fix size of allocated regions that need alignment padding
- fix compiling without OF_CONTROL
- fixed NULL pointer access in 'fdt_blob' passed to 'boot_fdt_add_mem_rsv_regions'
Changes in v5:
- added tests for lib/lmb.c
- fixed bug in lmb.c when ram is at the end of 32-bit address range
- fixed a bug in lmb_alloc_addr when resulting reserved ranges get combined
Changes in v4:
- fixed invalid 'if' statement without braces in boot_fdt_reserve_region
- removed patch 7 ("net: remove CONFIG_MCAST_TFTP), adapted patch 8
Changes in v3:
- No patch changes, but needed to resend since patman added too many cc addresses that gmail seemed to detect as spam :-(
Changes in v2:
- added code to reserve devicetree reserved-memory in lmb
- added tftp fixes (patches 7 and 8)
- fixed a bug in new function lmb_alloc_addr
Simon Goldschmidt (9): test: add test for lib/lmb.c lmb: fix allocation at end of address range lib: lmb: reserving overlapping regions should fail fdt: parse "reserved-memory" for memory reservation lib: lmb: extend lmb for checks at load time fs: prevent overwriting reserved memory bootm: use new common function lmb_init_and_reserve lmb: remove unused extern declaration tftp: prevent overwriting reserved memory
common/bootm.c | 8 +- common/image-fdt.c | 53 +++- fs/fs.c | 56 ++++- include/lmb.h | 7 +- lib/Makefile | 1 + lib/lmb.c | 106 ++++++-- net/tftp.c | 73 +++++- test/lib/Makefile | 1 + test/lib/lmb.c | 601 +++++++++++++++++++++++++++++++++++++++++++++ 9 files changed, 853 insertions(+), 53 deletions(-) create mode 100644 test/lib/lmb.c