twx-linux/kernel
Andrii Nakryiko cf5fe3c71c bpf: make __reg{32,64}_deduce_bounds logic more robust
This change doesn't seem to have any effect on selftests and production
BPF object files, but we preemptively try to make it more robust.

First, "learn sign from signed bounds" comment is misleading, as we are
learning not just sign, but also values.

Second, we simplify the check for determining whether entire range is
positive or negative similarly to other checks added earlier, using
appropriate u32/u64 cast and single comparisons. As explain in comments
in __reg64_deduce_bounds(), the checks are equivalent.

Last but not least, smin/smax and s32_min/s32_max reassignment based on
min/max of both umin/umax and smin/smax (and 32-bit equivalents) is hard
to explain and justify. We are updating unsigned bounds from signed
bounds, why would we update signed bounds at the same time? This might
be correct, but it's far from obvious why and the code or comments don't
try to justify this. Given we've added a separate deduction of signed
bounds from unsigned bounds earlier, this seems at least redundant, if
not just wrong.

In short, we remove doubtful pieces, and streamline the rest to follow
the logic and approach of the rest of reg_bounds_sync() checks.

Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231112010609.848406-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-11-15 12:03:42 -08:00
..
bpf bpf: make __reg{32,64}_deduce_bounds logic more robust 2023-11-15 12:03:42 -08:00
cgroup Merge branch 'for-6.8-bpf' of https://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup into bpf-next 2023-11-10 09:02:13 -08:00
configs hardening: Provide Kconfig fragments for basic options 2023-09-22 09:50:55 -07:00
debug kdb: Corrects comment for kdballocenv 2023-11-06 17:13:55 +00:00
dma dma-mapping updates for Linux 6.7 2023-11-01 13:15:54 -10:00
entry entry: Remove empty addr_limit_user_check() 2023-08-23 10:32:39 +02:00
events Many singleton patches against the MM code. The patch series which are 2023-11-02 19:38:47 -10:00
futex io_uring-futex-2023-10-30 2023-11-01 11:25:08 -10:00
gcov gcov: annotate struct gcov_iterator with __counted_by 2023-10-18 14:43:22 -07:00
irq As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
kcsan mm: delete checks for xor_unlock_is_negative_byte() 2023-10-18 14:34:17 -07:00
livepatch livepatch: Fix missing newline character in klp_resolve_symbols() 2023-09-20 11:24:18 +02:00
locking RCU pull request for v6.7 2023-10-30 18:01:41 -10:00
module This update includes the following changes: 2023-11-02 16:15:30 -10:00
power Power management updates for 6.7-rc1 2023-10-31 15:38:12 -10:00
printk TTY/Serial changes for 6.7-rc1 2023-11-03 15:44:25 -10:00
rcu RCU fixes for v6.7 2023-11-08 09:47:52 -08:00
sched As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
time Networking changes for 6.7. 2023-10-31 05:10:11 -10:00
trace bpf: Add __bpf_dynptr_data* for in kernel use 2023-11-09 19:07:38 -08:00
.gitignore
acct.c fs: rename __mnt_{want,drop}_write*() helpers 2023-09-11 15:05:50 +02:00
async.c
audit_fsnotify.c
audit_tree.c As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
audit_watch.c audit: don't take task_lock() in audit_exe_compare() code path 2023-10-25 22:29:47 -04:00
audit.c audit: move trailing statements to next line 2023-08-15 18:16:14 -04:00
audit.h audit: correct audit_filter_inodes() definition 2023-07-21 12:17:25 -04:00
auditfilter.c audit: move trailing statements to next line 2023-08-15 18:16:14 -04:00
auditsc.c audit,io_uring: io_uring openat triggers audit reference count underflow 2023-10-13 18:34:46 +02:00
backtracetest.c
bounds.c
capability.c lsm: constify the 'target' parameter in security_capget() 2023-08-08 16:48:47 -04:00
cfi.c
compat.c
configs.c
context_tracking.c
cpu_pm.c
cpu.c asm-generic updates for v6.7 2023-11-01 15:28:33 -10:00
crash_core.c crash_core.c: remove unneeded functions 2023-10-04 10:41:58 -07:00
crash_dump.c
cred.c lsm/stable-6.7 PR 20231030 2023-10-30 20:13:17 -10:00
delayacct.c
dma.c
exec_domain.c
exit.c As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
exit.h exit: add internal include file with helpers 2023-09-21 12:03:50 -06:00
extable.c
fail_function.c
fork.c As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
freezer.c freezer,sched: Use saved_state to reduce some spurious wakeups 2023-09-18 08:14:36 +02:00
gen_kheaders.sh
groups.c groups: Convert group_info.usage to refcount_t 2023-09-29 11:28:39 -07:00
hung_task.c
iomem.c kernel/iomem.c: remove __weak ioremap_cache helper 2023-08-21 13:37:28 -07:00
irq_work.c
jump_label.c
kallsyms_internal.h
kallsyms_selftest.c Modules changes for v6.6-rc1 2023-08-29 17:32:32 -07:00
kallsyms_selftest.h
kallsyms.c kallsyms: Change func signature for cleanup_symbol_name() 2023-08-25 15:00:36 -07:00
kcmp.c file: convert to SLAB_TYPESAFE_BY_RCU 2023-10-19 11:02:48 +02:00
Kconfig.freezer
Kconfig.hz
Kconfig.kexec docs: fix link s390/zfcpdump.rst 2023-10-04 10:41:56 -07:00
Kconfig.locks
Kconfig.preempt
kcov.c
kexec_core.c crash_core: move crashk_*res definition into crash_core.c 2023-10-04 10:41:58 -07:00
kexec_elf.c
kexec_file.c integrity-v6.6 2023-08-30 09:16:56 -07:00
kexec_internal.h
kexec.c kernel: kexec: copy user-array safely 2023-10-09 16:59:47 +10:00
kheaders.c
kprobes.c kprobes: kretprobe scalability improvement 2023-10-18 23:59:54 +09:00
ksyms_common.c
ksysfs.c crash: hotplug support for kexec_load() 2023-08-24 16:25:14 -07:00
kthread.c As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
latencytop.c
Makefile
module_signature.c
notifier.c
nsproxy.c nsproxy: Convert nsproxy.count to refcount_t 2023-08-21 11:29:12 -07:00
padata.c padata: Fix refcnt handling in padata_free_shell() 2023-10-27 18:04:24 +08:00
panic.c panic: use atomic_try_cmpxchg in panic() and nmi_panic() 2023-10-04 10:41:56 -07:00
params.c
pid_namespace.c pid: pid_ns_ctl_handler: remove useless comment 2023-10-04 10:41:57 -07:00
pid_sysctl.h memfd: replace ratcheting feature from vm.memfd_noexec with hierarchy 2023-08-21 13:37:59 -07:00
pid.c pidfd: prevent a kernel-doc warning 2023-09-19 13:21:33 -07:00
profile.c
ptrace.c mm: make __access_remote_vm() static 2023-10-18 14:34:15 -07:00
range.c
reboot.c kernel/reboot: Add device to sys_off_handler 2023-07-28 11:33:09 +01:00
regset.c
relay.c kernel: relay: remove unnecessary NULL values from relay_open_buf 2023-08-18 10:18:55 -07:00
resource_kunit.c
resource.c resource: Unify next_resource() and next_resource_skip_children() 2023-10-05 13:58:07 +02:00
rseq.c
scftorture.c scftorture: Pause testing after memory-allocation failure 2023-07-14 15:02:57 -07:00
scs.c
seccomp.c seccomp: Add missing kerndoc notations 2023-08-17 12:32:15 -07:00
signal.c As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
smp.c CSD lock commits for v6.7 2023-10-30 17:56:53 -10:00
smpboot.c kthread: add kthread_stop_put 2023-10-04 10:41:57 -07:00
smpboot.h
softirq.c sched/core: introduce sched_core_idle_cpu() 2023-07-13 15:21:50 +02:00
stackleak.c
stacktrace.c stacktrace: Export stack_trace_save_tsk 2023-09-11 23:59:47 -04:00
static_call_inline.c
static_call.c
stop_machine.c
sys_ni.c asm-generic updates for v6.7 2023-11-01 15:28:33 -10:00
sys.c As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
sysctl-test.c
sysctl.c asm-generic updates for v6.7 2023-11-01 15:28:33 -10:00
task_work.c task_work: add kerneldoc annotation for 'data' argument 2023-09-19 13:21:32 -07:00
taskstats.c taskstats: fill_stats_for_tgid: use for_each_thread() 2023-10-04 10:41:57 -07:00
torture.c torture: Print out torture module parameters 2023-09-24 17:24:01 +02:00
tracepoint.c
tsacct.c
ucount.c sysctl: Add size to register_sysctl 2023-08-15 15:26:17 -07:00
uid16.c
uid16.h
umh.c
up.c smp: Change function signatures to use call_single_data_t 2023-09-13 14:59:24 +02:00
user_namespace.c As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
user-return-notifier.c
user.c binfmt_misc: enable sandboxed mounts 2023-10-11 08:46:01 -07:00
usermode_driver.c
utsname_sysctl.c
utsname.c
vhost_task.c
watch_queue.c kernel: watch_queue: copy user-array safely 2023-10-09 16:59:48 +10:00
watchdog_buddy.c
watchdog_perf.c
watchdog.c watchdog: move softlockup_panic back to early_param 2023-11-01 12:10:02 -07:00
workqueue_internal.h workqueue: Drop the special locking rule for worker->flags and worker_pool->flags 2023-08-07 15:57:22 -10:00
workqueue.c As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00