linux/kernel
Alexei Starovoitov ceefbc96fa bpf: add per-insn complexity limit
malicious bpf program may try to force the verifier to remember
a lot of distinct verifier states.
Put a limit to number of per-insn 'struct bpf_verifier_state'.
Note that hitting the limit doesn't reject the program.
It potentially makes the verifier do more steps to analyze the program.
It means that malicious programs will hit BPF_COMPLEXITY_LIMIT_INSNS sooner
instead of spending cpu time walking long link list.

The limit of BPF_COMPLEXITY_LIMIT_STATES==64 affects cilium progs
with slight increase in number of "steps" it takes to successfully verify
the programs:
                       before    after
bpf_lb-DLB_L3.o         1940      1940
bpf_lb-DLB_L4.o         3089      3089
bpf_lb-DUNKNOWN.o       1065      1065
bpf_lxc-DDROP_ALL.o     28052  |  28162
bpf_lxc-DUNKNOWN.o      35487  |  35541
bpf_netdev.o            10864     10864
bpf_overlay.o           6643      6643
bpf_lcx_jit.o           38437     38437

But it also makes malicious program to be rejected in 0.4 seconds vs 6.5
Hence apply this limit to unprivileged programs only.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-12-04 17:22:02 +01:00
..
bpf bpf: add per-insn complexity limit 2018-12-04 17:22:02 +01:00
cgroup for-linus-20181102 2018-11-02 11:25:48 -07:00
configs kvm_config: add CONFIG_VIRTIO_MENU 2018-10-24 20:55:56 -04:00
debug kdb: kdb_support: mark expected switch fall-throughs 2018-11-13 20:38:50 +00:00
dma mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
events Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-11-03 18:13:43 -07:00
gcov
irq irq/matrix: Fix memory overallocation 2018-11-01 10:00:38 +01:00
livepatch
locking mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
power memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
printk mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
rcu
sched Merge branch 'akpm' (patches from Andrew) 2018-11-18 11:31:26 -08:00
time posix-cpu-timers: Remove useless call to check_dl_overrun() 2018-11-08 07:43:35 +01:00
trace bpf: fix check of allowed specifiers in bpf_trace_printk 2018-11-23 21:54:14 +01:00
.gitignore
acct.c
async.c
audit.c
audit.h
audit_fsnotify.c
audit_tree.c
audit_watch.c
auditfilter.c
auditsc.c
backtracetest.c
bounds.c kbuild: fix kernel/bounds.c 'W=1' warning 2018-10-31 08:54:14 -07:00
capability.c
compat.c
configs.c
context_tracking.c
cpu.c Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 18:43:04 +01:00
cpu_pm.c
crash_core.c
crash_dump.c
cred.c
delayacct.c delayacct: track delays from thrashing cache pages 2018-10-26 16:26:32 -07:00
dma.c
elfcore.c
exec_domain.c
exit.c
extable.c
fail_function.c kernel/fail_function.c: remove meaningless null pointer check before debugfs_remove_recursive 2018-10-31 08:54:12 -07:00
fork.c New gcc plugin: stackleak 2018-11-01 11:46:27 -07:00
freezer.c
futex.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
futex_compat.c
groups.c
hung_task.c kernel: hung_task.c: disable on suspend 2018-10-25 18:45:08 +02:00
iomem.c
irq_work.c
jump_label.c Merge branch 'x86/build' into locking/core, to pick up dependent patches and unify jump-label work 2018-10-16 17:30:11 +02:00
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c
kexec.c
kexec_core.c kexec: Allocate decrypted control pages for kdump if SME is enabled 2018-10-06 12:01:51 +02:00
kexec_file.c kernel/kexec_file.c: remove some duplicated includes 2018-11-03 10:09:37 -07:00
kexec_internal.h
kmod.c
kprobes.c
ksysfs.c
kthread.c
latencytop.c
Makefile
memremap.c Merge branch 'xarray' of git://git.infradead.org/users/willy/linux-dax 2018-10-28 11:35:40 -07:00
module-internal.h
module.c jump_table: Move entries into ro_after_init region 2018-09-27 17:56:49 +02:00
module_signing.c
notifier.c
nsproxy.c
padata.c
panic.c kernel/panic.c: filter out a potential trailing newline 2018-10-31 08:54:14 -07:00
params.c
pid.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
pid_namespace.c
profile.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
ptrace.c Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-10-24 11:22:39 +01:00
range.c
reboot.c
relay.c
resource.c resource/docs: Complete kernel-doc style function documentation 2018-11-07 16:47:47 +01:00
rseq.c
seccomp.c Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2018-10-24 11:49:35 +01:00
signal.c kernel/signal.c: fix a comment error 2018-10-31 08:54:14 -07:00
smp.c smp,cpumask: introduce on_each_cpu_cond_mask 2018-10-09 16:51:11 +02:00
smpboot.c
smpboot.h
softirq.c Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-25 11:43:47 -07:00
stackleak.c
stacktrace.c
stop_machine.c
sys.c
sys_ni.c
sysctl.c kernel/sysctl.c: remove duplicated include 2018-11-03 10:09:37 -07:00
sysctl_binary.c
task_work.c
taskstats.c
test_kprobes.c
torture.c
tracepoint.c tracepoint: Fix tracepoint array element size mismatch 2018-10-17 15:35:29 -04:00
tsacct.c
ucount.c
uid16.c
uid16.h
umh.c umh: Add command line to user mode helpers 2018-10-22 19:37:36 -07:00
up.c smp,cpumask: introduce on_each_cpu_cond_mask 2018-10-09 16:51:11 +02:00
user-return-notifier.c
user.c
user_namespace.c userns: also map extents in the reverse map to kernel IDs 2018-11-07 23:51:16 -06:00
utsname.c
utsname_sysctl.c
watchdog.c
watchdog_hld.c
workqueue.c
workqueue_internal.h