twx-linux/kernel
Eduard Zingerman bbbc02b744 bpf: copy_verifier_state() should copy 'loop_entry' field
The bpf_verifier_state.loop_entry state should be copied by
copy_verifier_state(). Otherwise, .loop_entry values from unrelated
states would poison env->cur_state.

Additionally, env->stack should not contain any states with
.loop_entry != NULL. The states in env->stack are yet to be verified,
while .loop_entry is set for states that reached an equivalent state.
This means that env->cur_state->loop_entry should always be NULL after
pop_stack().

See the selftest in the next commit for an example of the program that
is not safe yet is accepted by verifier w/o this fix.

This change has some verification performance impact for selftests:

File                                Program                       Insns (A)  Insns (B)  Insns   (DIFF)  States (A)  States (B)  States (DIFF)
----------------------------------  ----------------------------  ---------  ---------  --------------  ----------  ----------  -------------
arena_htab.bpf.o                    arena_htab_llvm                     717        426  -291 (-40.59%)          57          37  -20 (-35.09%)
arena_htab_asm.bpf.o                arena_htab_asm                      597        445  -152 (-25.46%)          47          37  -10 (-21.28%)
arena_list.bpf.o                    arena_list_del                      309        279    -30 (-9.71%)          23          14   -9 (-39.13%)
iters.bpf.o                         iter_subprog_check_stacksafe        155        141    -14 (-9.03%)          15          14    -1 (-6.67%)
iters.bpf.o                         iter_subprog_iters                 1094       1003    -91 (-8.32%)          88          83    -5 (-5.68%)
iters.bpf.o                         loop_state_deps2                    479        725  +246 (+51.36%)          46          63  +17 (+36.96%)
kmem_cache_iter.bpf.o               open_coded_iter                      63         59     -4 (-6.35%)           7           6   -1 (-14.29%)
verifier_bits_iter.bpf.o            max_words                            92         84     -8 (-8.70%)           8           7   -1 (-12.50%)
verifier_iterating_callbacks.bpf.o  cond_break2                         113        107     -6 (-5.31%)          12          12    +0 (+0.00%)

And significant negative impact for sched_ext:

File               Program                 Insns (A)  Insns (B)  Insns         (DIFF)  States (A)  States (B)  States      (DIFF)
-----------------  ----------------------  ---------  ---------  --------------------  ----------  ----------  ------------------
bpf.bpf.o          lavd_init                    7039      14723      +7684 (+109.16%)         490        1139     +649 (+132.45%)
bpf.bpf.o          layered_dispatch            11485      10548         -937 (-8.16%)         848         762       -86 (-10.14%)
bpf.bpf.o          layered_dump                 7422    1000001  +992579 (+13373.47%)         681       31178  +30497 (+4478.27%)
bpf.bpf.o          layered_enqueue             16854      71127     +54273 (+322.02%)        1611        6450    +4839 (+300.37%)
bpf.bpf.o          p2dq_dispatch                 665        791        +126 (+18.95%)          68          78       +10 (+14.71%)
bpf.bpf.o          p2dq_init                    2343       2980        +637 (+27.19%)         201         237       +36 (+17.91%)
bpf.bpf.o          refresh_layer_cpumasks      16487     674760   +658273 (+3992.68%)        1770       65370  +63600 (+3593.22%)
bpf.bpf.o          rusty_select_cpu             1937      40872    +38935 (+2010.07%)         177        3210   +3033 (+1713.56%)
scx_central.bpf.o  central_dispatch              636       2687      +2051 (+322.48%)          63         227     +164 (+260.32%)
scx_nest.bpf.o     nest_init                     636        815        +179 (+28.14%)          60          73       +13 (+21.67%)
scx_qmap.bpf.o     qmap_dispatch                2393       3580       +1187 (+49.60%)         196         253       +57 (+29.08%)
scx_qmap.bpf.o     qmap_dump                     233        318         +85 (+36.48%)          22          30        +8 (+36.36%)
scx_qmap.bpf.o     qmap_init                   16367      17436        +1069 (+6.53%)         603         669       +66 (+10.95%)

Note 'layered_dump' program, which now hits 1M instructions limit.
This impact would be mitigated in the next patch.

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250215110411.3236773-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18 19:22:58 -08:00
..
bpf bpf: copy_verifier_state() should copy 'loop_entry' field 2025-02-18 19:22:58 -08:00
cgroup drm next for 6.14-rc1 2025-01-21 16:09:47 -08:00
configs configs/debug: make sure PROVE_RCU_LIST=y takes effect 2024-10-28 10:21:09 -07:00
debug kdb: Remove unused flags stack 2025-01-25 08:22:26 +00:00
dma dma-debug: fix physical address calculation for struct dma_debug_entry 2024-11-28 10:19:16 +01:00
entry sched: Add TIF_NEED_RESCHED_LAZY infrastructure 2024-11-05 12:55:37 +01:00
events kernel: be more careful about dup_mmap() failures and uprobe registering 2025-02-01 03:53:25 -08:00
futex Mainly individually changelogged singleton patches. The patch series in 2025-01-26 17:50:53 -08:00
gcov gcov: clang: use correct function param names 2025-01-24 22:47:27 -08:00
irq Updates for the interrupt subsystem: 2025-01-21 13:51:07 -08:00
kcsan kcsan: Remove redundant call of kallsyms_lookup_name() 2024-10-14 16:44:56 +02:00
livepatch livepatch: Add stack_order sysfs attribute 2024-12-09 11:44:03 +01:00
locking treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
module Kbuild updates for v6.14 2025-01-31 12:07:07 -08:00
power More power management updates for 6.14-rc1 2025-01-30 15:10:34 -08:00
printk treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
rcu The various patchsets are summarized below. Plus of course many 2025-01-26 18:36:23 -08:00
sched More power management updates for 6.14-rc1 2025-01-30 15:10:34 -08:00
time treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
trace treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
.gitignore
acct.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
async.c
audit_fsnotify.c
audit_tree.c
audit_watch.c
audit.c audit: Initialize lsmctx to avoid memory allocation error 2025-01-29 20:02:04 -05:00
audit.h audit: change context data from secid to lsm_prop 2024-10-11 14:34:16 -04:00
auditfilter.c audit: fix suffixed '/' filename matching 2024-12-05 19:22:38 -05:00
auditsc.c lsm/stable-6.14 PR 20250121 2025-01-21 20:03:04 -08:00
backtracetest.c backtracetest: add MODULE_DESCRIPTION() 2024-06-24 22:24:55 -07:00
bounds.c bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS 2024-04-29 08:29:29 -07:00
capability.c kernel: remove get_task_comm() and print task comm directly 2025-01-12 20:21:15 -08:00
cfi.c
compat.c
configs.c
context_tracking.c context_tracking, rcu: Rename rcu_dyntick trace event into rcu_watching 2024-08-15 21:30:43 +05:30
cpu_pm.c
cpu.c The various patchsets are summarized below. Plus of course many 2025-01-26 18:36:23 -08:00
crash_core.c kexec/crash: no crash update when kexec in progress 2024-11-05 17:12:27 -08:00
crash_reserve.c crash: fix crash memory reserve exceed system memory bug 2024-09-01 20:43:30 -07:00
cred.c cred: remove old {override,revert}_creds() helpers 2024-12-02 11:25:09 +01:00
delayacct.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
dma.c
elfcorehdr.c
exec_domain.c
exit.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
exit.h
extable.c
fail_function.c
fork.c kernel: be more careful about dup_mmap() failures and uprobe registering 2025-02-01 03:53:25 -08:00
freezer.c sched/fair: Fix external p->on_rq users 2024-10-14 09:14:35 +02:00
gen_kheaders.sh Kbuild updates for v6.14 2025-01-31 12:07:07 -08:00
groups.c
hung_task.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
iomem.c
irq_work.c kasan: make kasan_record_aux_stack_noalloc() the default behaviour 2025-01-13 22:40:36 -08:00
jump_label.c jump_label: Fix static_key_slow_dec() yet again 2024-09-10 11:57:27 +02:00
kallsyms_internal.h kallsyms: get rid of code for absolute kallsyms 2024-07-20 16:33:21 +09:00
kallsyms_selftest.c kallsyms: Use kthread_run_on_cpu() 2025-01-02 22:12:12 +01:00
kallsyms_selftest.h
kallsyms.c kallsyms: Match symbols exactly with CONFIG_LTO_CLANG 2024-08-15 09:33:35 -07:00
kcmp.c get rid of ...lookup...fdget_rcu() family 2024-10-07 13:34:41 -04:00
Kconfig.freezer
Kconfig.hz
Kconfig.kexec crash, powerpc: default to CRASH_DUMP=n on PPC_BOOK3S_32 2024-11-14 22:43:48 -08:00
Kconfig.locks
Kconfig.preempt sched: No PREEMPT_RT=y for all{yes,mod}config 2024-11-07 15:25:05 +01:00
kcov.c kcov: mark in_softirq_really() as __always_inline 2024-12-30 17:59:08 -08:00
kexec_core.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
kexec_elf.c
kexec_file.c kexec_file: fix elfcorehdr digest exclusion when CONFIG_CRASH_HOTPLUG=y 2024-09-01 17:59:01 -07:00
kexec_internal.h kexec: use atomic_try_cmpxchg_acquire() in kexec_trylock() 2024-09-01 20:43:23 -07:00
kexec.c
kheaders.c kheaders: Simplify attribute through __BIN_ATTR_SIMPLE_RO() 2024-12-24 09:46:49 +01:00
kprobes.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
ksyms_common.c
ksysfs.c kernel/ksysfs.c: simplify bin_attribute definition 2025-01-07 16:59:15 +01:00
kthread.c Mainly individually changelogged singleton patches. The patch series in 2025-01-26 17:50:53 -08:00
latencytop.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
Makefile mm: move kernel/numa.c to mm/ 2024-09-03 21:15:26 -07:00
module_signature.c
notifier.c reboot: move reboot_notifier_list to kernel/reboot.c 2024-11-05 17:12:31 -08:00
nsproxy.c fdget(), trivial conversions 2024-11-03 01:28:06 -05:00
padata.c padata: avoid UAF for reorder_work 2025-01-19 12:44:28 +08:00
panic.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
params.c module: Constify 'struct module_attribute' 2025-01-26 13:05:23 +01:00
pid_namespace.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
pid_sysctl.h treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
pid.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
profile.c profiling: remove profile=sleep support 2024-08-04 13:36:28 -07:00
ptrace.c
range.c
reboot.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
regset.c regset: use kvzalloc() for regset_get_alloc() 2024-04-25 21:07:03 -07:00
relay.c [tree-wide] finally take no_llseek out 2024-09-27 08:18:43 -07:00
resource_kunit.c resource, kunit: fix user-after-free in resource_test_region_intersects() 2024-10-09 12:47:19 -07:00
resource.c kernel/resource: simplify API __devm_release_region() implementation 2025-01-12 20:20:58 -08:00
rseq.c rseq: Fix rseq unregistration regression 2025-01-21 08:10:51 +01:00
scftorture.c scftorture: Handle NULL argument passed to scf_add_to_free_list(). 2024-11-14 16:09:51 -08:00
scs.c
seccomp.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
signal.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
smp.c CSD-lock pull request for v6.14 2025-01-28 11:34:03 -08:00
smpboot.c
smpboot.h
softirq.c softirq: Allow raising SCHED_SOFTIRQ from SMP-call-function on RT kernel 2024-12-02 12:01:27 +01:00
stackleak.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
stacktrace.c
static_call_inline.c x86/static-call: provide a way to do very early static-call updates 2024-12-13 09:28:32 +01:00
static_call.c
stop_machine.c stop_machine: Fix rcu_momentary_eqs() call in multi_cpu_stop() 2024-12-11 20:50:47 -08:00
sys_ni.c Probes updates for v6.11: 2024-07-18 12:19:20 -07:00
sys.c tracing: Add task_prctl_unknown tracepoint 2024-12-22 20:28:11 -08:00
sysctl-test.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
sysctl.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
task_work.c kasan: make kasan_record_aux_stack_noalloc() the default behaviour 2025-01-13 22:40:36 -08:00
taskstats.c fdget(), more trivial conversions 2024-11-03 01:28:06 -05:00
torture.c torture: Add MODULE_DESCRIPTION() 2024-05-30 15:31:38 -07:00
tracepoint.c tracing: Fix syscall tracepoint use-after-free 2024-11-01 14:37:31 -04:00
tsacct.c tsacct: replace strncpy() with strscpy() 2024-07-12 16:39:53 -07:00
ucount.c ucounts: move kfree() out of critical zone protected by ucounts_lock 2025-01-12 20:21:00 -08:00
uid16.c
uid16.h
umh.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
up.c
user_namespace.c user_namespace: use kmemdup_array() instead of kmemdup() for multiple allocation 2024-09-09 16:47:42 -07:00
user-return-notifier.c
user.c uidgid: make sure we fit into one cacheline 2024-09-12 12:16:09 +02:00
usermode_driver.c
utsname_sysctl.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
utsname.c
vhost_task.c vhost_task: Handle SIGKILL by flushing work and exiting 2024-05-22 08:31:15 -04:00
vmcore_info.c mm: support only one page_type per page 2024-09-03 21:15:43 -07:00
watch_queue.c watch_queue: Use page->private instead of page->index 2024-12-22 11:29:51 +01:00
watchdog_buddy.c
watchdog_perf.c watchdog/perf: properly initialize the turbo mode timestamp and rearm counter 2024-07-17 21:11:34 -07:00
watchdog.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
workqueue_internal.h
workqueue.c The various patchsets are summarized below. Plus of course many 2025-01-26 18:36:23 -08:00