[PATCH 00/64] Introduce strict memcpy() bounds checking

Kees Cook
2021-07-27T21:01:35Z

Hi,

This patch series (based on next-20210726) implements stricter (no struct
member overflows) bounds checking for memcpy(), memmove(), and memset()
under CONFIG_FORTIFY_SOURCE. To quote a later patch in the series:

tl;dr: In order to eliminate a large class of common buffer overflow
flaws that continue to persist in the kernel, have memcpy() (under
CONFIG_FORTIFY_SOURCE) perform bounds checking of the destination struct
member when they have a known size. This would have caught all of the
memcpy()-related buffer write overflow flaws identified in at least the
last three years.

As this series introduces various helpers and performs several phases of
treewide cleanups, I'm expecting to carry this series in my tree, so I'd
love to get some Reviews and Acks. Given the size, I've mostly aimed this
series at various mailing lists, otherwise the CC size got really big. :)

Specifically, this series is logically split into several steps:

Clean up remaining simple compile-time memcpy() warnings:
media: omap3isp: Extract struct group for memcpy() region
mac80211: Use flex-array for radiotap header bitmap
rpmsg: glink: Replace strncpy() with strscpy_pad()

Introduce struct_group() and apply it treewide to avoid compile-time
memcpy() warnings:
stddef: Introduce struct_group() helper macro
skbuff: Switch structure bounds to struct_group()
bnxt_en: Use struct_group_attr() for memcpy() region
staging: rtl8192e: Use struct_group() for memcpy() region
staging: rtl8192u: Use struct_group() for memcpy() region
staging: rtl8723bs: Avoid field-overflowing memcpy()
lib80211: Use struct_group() for memcpy() region
net/mlx5e: Avoid field-overflowing memcpy()
mwl8k: Use struct_group() for memcpy() region
libertas: Use struct_group() for memcpy() region
libertas_tf: Use struct_group() for memcpy() region
ipw2x00: Use struct_group() for memcpy() region
thermal: intel: int340x_thermal: Use struct_group() for memcpy() region
iommu/amd: Use struct_group() for memcpy() region
cxgb3: Use struct_group() for memcpy() region
ip: Use struct_group() for memcpy() regions
intersil: Use struct_group() for memcpy() region
cxgb4: Use struct_group() for memcpy() region
bnx2x: Use struct_group() for memcpy() region
drm/amd/pm: Use struct_group() for memcpy() region
staging: wlan-ng: Use struct_group() for memcpy() region
drm/mga/mga_ioc32: Use struct_group() for memcpy() region
net/mlx5e: Use struct_group() for memcpy() region
HID: cp2112: Use struct_group() for memcpy() region

Prepare fortify for additional hardening:
compiler_types.h: Remove __compiletime_object_size()
lib/string: Move helper functions out of string.c
fortify: Move remaining fortify helpers into fortify-string.h
fortify: Explicitly disable Clang support

Add compile-time and run-time tests:
fortify: Add compile-time FORTIFY_SOURCE tests
lib: Introduce CONFIG_TEST_MEMCPY

Enable new compile-time memcpy() and memmove() bounds checking:
fortify: Detect struct member overflows in memcpy() at compile-time
fortify: Detect struct member overflows in memmove() at compile-time

Clean up remaining simple compile-time memset() warnings:
scsi: ibmvscsi: Avoid multi-field memset() overflow by aiming at srp

Introduce memset_after() helper and apply it (and struct_group())
treewide to avoid compile-time memset() warnings:
string.h: Introduce memset_after() for wiping trailing members/padding
xfrm: Use memset_after() to clear padding
mac80211: Use memset_after() to clear tx status
net: 802: Use memset_after() to clear struct fields
net: dccp: Use memset_after() for TP zeroing
net: qede: Use memset_after() for counters
ath11k: Use memset_after() for clearing queue descriptors
iw_cxgb4: Use memset_after() for cpl_t5_pass_accept_rpl
intel_th: msu: Use memset_after() for clearing hw header
IB/mthca: Use memset_after() for clearing mpt_entry
btrfs: Use memset_after() to clear end of struct
drbd: Use struct_group() to zero algs
cm4000_cs: Use struct_group() to zero struct cm4000_dev region
KVM: x86: Use struct_group() to zero decode cache
tracing: Use struct_group() to zero struct trace_iterator
dm integrity: Use struct_group() to zero struct journal_sector
HID: roccat: Use struct_group() to zero kone_mouse_event
ipv6: Use struct_group() to zero rt6_info
RDMA/mlx5: Use struct_group() to zero struct mlx5_ib_mr
ethtool: stats: Use struct_group() to clear all stats at once
netfilter: conntrack: Use struct_group() to zero struct nf_conn
powerpc: Split memset() to avoid multi-field overflow

Enable new compile-time memset() bounds checking:
fortify: Detect struct member overflows in memset() at compile-time

Enable Clang support and global array-bounds checking:
fortify: Work around Clang inlining bugs
Makefile: Enable -Warray-bounds

Avoid run-time memcpy() bounds check warnings:
netlink: Avoid false-positive memcpy() warning
iwlwifi: dbg_ini: Split memcpy() to avoid multi-field write

Enable run-time memcpy() bounds checking:
fortify: Add run-time WARN for cross-field memcpy()

A future series will clean up for and add run-time memset() bounds
checking.

Thanks!

-Kees

Makefile | 1 -
arch/s390/lib/string.c | 3 +
arch/x86/boot/compressed/misc.c | 3 +-
arch/x86/kvm/emulate.c | 3 +-
arch/x86/kvm/kvm_emulate.h | 19 +-
arch/x86/lib/memcpy_32.c | 1 +
arch/x86/lib/string_32.c | 1 +
drivers/block/drbd/drbd_main.c | 3 +-
drivers/block/drbd/drbd_protocol.h | 6 +-
drivers/block/drbd/drbd_receiver.c | 3 +-
drivers/char/pcmcia/cm4000_cs.c | 9 +-
drivers/gpu/drm/amd/include/atomfirmware.h | 9 +-
.../drm/amd/pm/inc/smu11_driver_if_arcturus.h | 3 +-
.../drm/amd/pm/inc/smu11_driver_if_navi10.h | 3 +-
.../amd/pm/inc/smu13_driver_if_aldebaran.h | 3 +-
.../gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c | 6 +-
.../gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c | 12 +-
.../drm/amd/pm/swsmu/smu13/aldebaran_ppt.c | 6 +-
drivers/gpu/drm/mga/mga_ioc32.c | 30 +-
drivers/hid/hid-cp2112.c | 14 +-
drivers/hid/hid-roccat-kone.c | 2 +-
drivers/hid/hid-roccat-kone.h | 12 +-
drivers/hwtracing/intel_th/msu.c | 4 +-
drivers/infiniband/hw/cxgb4/cm.c | 5 +-
drivers/infiniband/hw/mlx5/mlx5_ib.h | 4 +-
drivers/infiniband/hw/mthca/mthca_mr.c | 3 +-
drivers/iommu/amd/init.c | 9 +-
drivers/macintosh/smu.c | 3 +-
drivers/md/dm-integrity.c | 9 +-
drivers/media/platform/omap3isp/ispstat.c | 5 +-
.../net/ethernet/broadcom/bnx2x/bnx2x_stats.c | 7 +-
.../net/ethernet/broadcom/bnx2x/bnx2x_stats.h | 14 +-
drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c | 4 +-
drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.h | 14 +-
drivers/net/ethernet/chelsio/cxgb3/sge.c | 9 +-
drivers/net/ethernet/chelsio/cxgb4/sge.c | 8 +-
drivers/net/ethernet/chelsio/cxgb4/t4_msg.h | 2 +-
drivers/net/ethernet/chelsio/cxgb4/t4fw_api.h | 10 +-
drivers/net/ethernet/chelsio/cxgb4vf/sge.c | 7 +-
drivers/net/ethernet/mellanox/mlx5/core/en.h | 4 +-
.../net/ethernet/mellanox/mlx5/core/en/xdp.c | 4 +-
.../net/ethernet/mellanox/mlx5/core/en_tx.c | 2 +-
drivers/net/ethernet/qlogic/qede/qede_main.c | 2 +-
drivers/net/wireguard/queueing.h | 4 +-
drivers/net/wireless/ath/ath11k/hal_rx.c | 13 +-
drivers/net/wireless/ath/carl9170/tx.c | 4 +-
drivers/net/wireless/intel/ipw2x00/libipw.h | 12 +-
.../net/wireless/intel/ipw2x00/libipw_rx.c | 8 +-
drivers/net/wireless/intel/iwlwifi/fw/file.h | 2 +-
.../net/wireless/intel/iwlwifi/iwl-dbg-tlv.c | 3 +-
.../net/wireless/intersil/hostap/hostap_hw.c | 5 +-
.../wireless/intersil/hostap/hostap_wlan.h | 14 +-
drivers/net/wireless/intersil/p54/txrx.c | 4 +-
drivers/net/wireless/marvell/libertas/host.h | 10 +-
drivers/net/wireless/marvell/libertas/tx.c | 5 +-
.../marvell/libertas_tf/libertas_tf.h | 10 +-
.../net/wireless/marvell/libertas_tf/main.c | 3 +-
drivers/net/wireless/marvell/mwl8k.c | 10 +-
drivers/rpmsg/qcom_glink_native.c | 2 +-
drivers/scsi/ibmvscsi/ibmvscsi.c | 2 +-
drivers/staging/rtl8192e/rtllib.h | 20 +-
drivers/staging/rtl8192e/rtllib_crypt_ccmp.c | 3 +-
drivers/staging/rtl8192e/rtllib_rx.c | 8 +-
.../staging/rtl8192u/ieee80211/ieee80211.h | 24 +-
.../rtl8192u/ieee80211/ieee80211_crypt_ccmp.c | 3 +-
.../staging/rtl8192u/ieee80211/ieee80211_rx.c | 8 +-
drivers/staging/rtl8723bs/core/rtw_mlme.c | 2 +-
drivers/staging/rtl8723bs/core/rtw_security.c | 5 +-
drivers/staging/rtl8723bs/core/rtw_xmit.c | 5 +-
drivers/staging/wlan-ng/hfa384x.h | 16 +-
drivers/staging/wlan-ng/hfa384x_usb.c | 4 +-
.../intel/int340x_thermal/acpi_thermal_rel.c | 5 +-
.../intel/int340x_thermal/acpi_thermal_rel.h | 48 +--
fs/btrfs/root-tree.c | 5 +-
include/linux/compiler-gcc.h | 2 -
include/linux/compiler_types.h | 4 -
include/linux/fortify-string.h | 234 +++++++++++---
include/linux/ieee80211.h | 8 +-
include/linux/if_vlan.h | 6 +-
include/linux/skbuff.h | 9 +-
include/linux/stddef.h | 34 ++
include/linux/string.h | 26 +-
include/linux/thread_info.h | 2 +-
include/linux/trace_events.h | 26 +-
include/net/flow.h | 6 +-
include/net/ieee80211_radiotap.h | 24 +-
include/net/ip6_fib.h | 30 +-
include/net/mac80211.h | 4 +-
include/net/netfilter/nf_conntrack.h | 20 +-
include/uapi/drm/mga_drm.h | 37 ++-
include/uapi/linux/if_ether.h | 12 +-
include/uapi/linux/ip.h | 12 +-
include/uapi/linux/ipv6.h | 12 +-
include/uapi/linux/netlink.h | 1 +
include/uapi/linux/omap3isp.h | 44 ++-
kernel/trace/trace.c | 4 +-
lib/.gitignore | 2 +
lib/Kconfig.debug | 3 +
lib/Makefile | 32 ++
lib/string.c | 210 +------------
lib/string_helpers.c | 201 ++++++++++++
lib/test_fortify/read_overflow-memchr.c | 5 +
lib/test_fortify/read_overflow-memchr_inv.c | 5 +
lib/test_fortify/read_overflow-memcmp.c | 5 +
lib/test_fortify/read_overflow-memscan.c | 5 +
lib/test_fortify/read_overflow2-memcmp.c | 5 +
lib/test_fortify/read_overflow2-memcpy.c | 5 +
lib/test_fortify/read_overflow2-memmove.c | 5 +
.../read_overflow2_field-memcpy.c | 5 +
.../read_overflow2_field-memmove.c | 5 +
lib/test_fortify/test_fortify.h | 31 ++
lib/test_fortify/write_overflow-memcpy.c | 5 +
lib/test_fortify/write_overflow-memmove.c | 5 +
lib/test_fortify/write_overflow-memset.c | 5 +
lib/test_fortify/write_overflow-strlcpy.c | 5 +
lib/test_fortify/write_overflow-strncpy.c | 5 +
lib/test_fortify/write_overflow-strscpy.c | 5 +
.../write_overflow_field-memcpy.c | 5 +
.../write_overflow_field-memmove.c | 5 +
.../write_overflow_field-memset.c | 5 +
lib/test_memcpy.c | 297 ++++++++++++++++++
net/802/hippi.c | 2 +-
net/core/flow_dissector.c | 10 +-
net/core/skbuff.c | 14 +-
net/dccp/trace.h | 4 +-
net/ethtool/stats.c | 15 +-
net/ipv4/ip_output.c | 6 +-
net/ipv6/route.c | 4 +-
net/mac80211/rx.c | 2 +-
net/netfilter/nf_conntrack_core.c | 4 +-
net/netlink/af_netlink.c | 4 +-
net/wireless/lib80211_crypt_ccmp.c | 3 +-
net/wireless/radiotap.c | 5 +-
net/xfrm/xfrm_policy.c | 4 +-
net/xfrm/xfrm_user.c | 2 +-
scripts/test_fortify.sh | 64 ++++
security/Kconfig | 3 +
137 files changed, 1484 insertions(+), 633 deletions(-)
create mode 100644 lib/test_fortify/read_overflow-memchr.c
create mode 100644 lib/test_fortify/read_overflow-memchr_inv.c
create mode 100644 lib/test_fortify/read_overflow-memcmp.c
create mode 100644 lib/test_fortify/read_overflow-memscan.c
create mode 100644 lib/test_fortify/read_overflow2-memcmp.c
create mode 100644 lib/test_fortify/read_overflow2-memcpy.c
create mode 100644 lib/test_fortify/read_overflow2-memmove.c
create mode 100644 lib/test_fortify/read_overflow2_field-memcpy.c
create mode 100644 lib/test_fortify/read_overflow2_field-memmove.c
create mode 100644 lib/test_fortify/test_fortify.h
create mode 100644 lib/test_fortify/write_overflow-memcpy.c
create mode 100644 lib/test_fortify/write_overflow-memmove.c
create mode 100644 lib/test_fortify/write_overflow-memset.c
create mode 100644 lib/test_fortify/write_overflow-strlcpy.c
create mode 100644 lib/test_fortify/write_overflow-strncpy.c
create mode 100644 lib/test_fortify/write_overflow-strscpy.c
create mode 100644 lib/test_fortify/write_overflow_field-memcpy.c
create mode 100644 lib/test_fortify/write_overflow_field-memmove.c
create mode 100644 lib/test_fortify/write_overflow_field-memset.c
create mode 100644 lib/test_memcpy.c
create mode 100644 scripts/test_fortify.sh

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2.30.2