Daniel Borkmann
ae968e270f
bpf: Fix pointer arithmetic mask tightening under state pruning
...
commit e042aa532c84d18ff13291d00620502ce7a38dda upstream.
In 7fedb63a8307 ("bpf: Tighten speculative pointer arithmetic mask") we
narrowed the offset mask for unprivileged pointer arithmetic in order to
mitigate a corner case where in the speculative domain it is possible to
advance, for example, the map value pointer by up to value_size-1 out-of-
bounds in order to leak kernel memory via side-channel to user space.
The verifier's state pruning for scalars leaves one corner case open
where in the first verification path R_x holds an unknown scalar with an
aux->alu_limit of e.g. 7, and in a second verification path that same
register R_x, here denoted as R_x', holds an unknown scalar which has
tighter bounds and would thus satisfy range_within(R_x, R_x') as well as
tnum_in(R_x, R_x') for state pruning, yielding an aux->alu_limit of 3:
Given the second path fits the register constraints for pruning, the final
generated mask from aux->alu_limit will remain at 7. While technically
not wrong for the non-speculative domain, it would however be possible
to craft similar cases where the mask would be too wide as in 7fedb63a8307.
One way to fix it is to detect the presence of unknown scalar map pointer
arithmetic and force a deeper search on unknown scalars to ensure that
we do not run into a masking mismatch.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[OP: adjusted context in include/linux/bpf_verifier.h for 5.4]
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-15 09:47:39 +02:00
..
bpf
bpf: Fix pointer arithmetic mask tightening under state pruning
2021-09-15 09:47:39 +02:00
cgroup
cgroup/cpuset: Fix a partition bug with hotplug
2021-09-15 09:47:32 +02:00
configs
debug
kdb: Make memory allocations more robust
2021-03-04 10:26:10 +01:00
dma
swiotlb: fix "x86: Don't panic if can not alloc buffer for swiotlb"
2020-11-18 19:20:32 +01:00
events
perf: Fix data race between pin_count increment/decrement
2021-06-16 11:59:44 +02:00
gcov
gcov: re-fix clang-11+ support
2021-04-14 08:24:10 +02:00
irq
genirq/timings: Fix error return code in irq_timings_test_irqs()
2021-09-15 09:47:29 +02:00
livepatch
locking
locking/mutex: Fix HANDOFF condition
2021-09-15 09:47:25 +02:00
power
PM: EM: Increase energy calculation precision
2021-09-15 09:47:33 +02:00
printk
printk: fix deadlock when kernel panic
2021-03-04 10:26:50 +01:00
rcu
rcu/tree: Handle VM stoppage in stall detection
2021-09-15 09:47:26 +02:00
sched
sched: Fix UCLAMP_FLAG_IDLE setting
2021-09-15 09:47:28 +02:00
time
hrtimer: Ensure timerfd notification for HIGHRES=n
2021-09-15 09:47:26 +02:00
trace
tracing / histogram: Fix NULL pointer dereference on strcmp() on NULL event name
2021-08-26 08:36:20 -04:00
.gitignore
kbuild: update config_data.gz only when the content of .config is changed
2021-05-11 14:04:16 +02:00
acct.c
async.c
audit.c
audit: fix a net reference leak in audit_list_rules_send()
2020-06-22 09:30:59 +02:00
audit.h
audit: fix a net reference leak in audit_list_rules_send()
2020-06-22 09:30:59 +02:00
audit_fsnotify.c
audit_tree.c
audit: move put_tree() to avoid trim_trees refcount underflow and UAF
2021-09-03 10:08:16 +02:00
audit_watch.c
audit: CONFIG_CHANGE don't log internal bookkeeping as an event
2020-10-01 13:17:32 +02:00
auditfilter.c
audit: fix a net reference leak in audit_list_rules_send()
2020-06-22 09:30:59 +02:00
auditsc.c
backtracetest.c
bounds.c
capability.c
compat.c
configs.c
context_tracking.c
cpu.c
cpu/hotplug: Cure the cpusets trainwreck
2021-07-19 08:53:15 +02:00
cpu_pm.c
kernel/cpu_pm: Fix uninitted local in cpu_pm
2020-06-22 09:31:22 +02:00
crash_core.c
crash_dump.c
cred.c
keys: Fix request_key() cache
2020-01-17 19:48:42 +01:00
delayacct.c
dma.c
exec_domain.c
exit.c
don't dump the threads that had been already exiting when zapped.
2020-11-18 19:20:31 +01:00
extable.c
fail_function.c
fail_function: Remove a redundant mutex unlock
2020-11-24 13:29:18 +01:00
fork.c
exec: Transform exec_update_mutex into a rw_semaphore
2021-01-09 13:44:55 +01:00
freezer.c
futex.c
mm, futex: fix shared futex pgoff on shmem huge page
2021-06-30 08:47:55 -04:00
gen_kheaders.sh
kbuild: add variables for compression tools
2020-09-03 11:27:10 +02:00
groups.c
hung_task.c
iomem.c
irq_work.c
jump_label.c
kallsyms.c
kallsyms: Refactor kallsyms_show_value() to take cred
2020-07-16 08:16:44 +02:00
kcmp.c
exec: Transform exec_update_mutex into a rw_semaphore
2021-01-09 13:44:55 +01:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c
kexec.c
kexec_core.c
kernel: kexec: remove the lock operation of system_transition_mutex
2021-02-03 23:25:56 +01:00
kexec_elf.c
kexec_file.c
kernel: kexec_file: fix error return code of kexec_calculate_store_digests()
2021-05-19 10:08:28 +02:00
kexec_internal.h
kheaders.c
kmod.c
kmod: make request_module() return an error when autoloading is disabled
2020-04-17 10:50:22 +02:00
kprobes.c
tracing/kprobe: Fix to support kretprobe events on unloaded modules
2021-02-13 13:52:54 +01:00
ksysfs.c
kthread.c
kthread: Fix PF_KTHREAD vs to_kthread() race
2021-09-12 08:56:39 +02:00
latencytop.c
Makefile
kbuild: update config_data.gz only when the content of .config is changed
2021-05-11 14:04:16 +02:00
module-internal.h
module.c
module: limit enabling module.sig_enforce
2021-06-30 08:47:42 -04:00
module_signature.c
module: harden ELF info handling
2021-04-07 14:47:38 +02:00
module_signing.c
module: harden ELF info handling
2021-04-07 14:47:38 +02:00
notifier.c
kernel/notifier.c: intercept duplicate registrations to avoid infinite loops
2020-10-01 13:17:23 +02:00
nsproxy.c
padata.c
padata: add separate cpuhp node for CPUHP_PADATA_DEAD
2020-06-17 16:40:22 +02:00
panic.c
params.c
pid.c
pid_namespace.c
profile.c
ptrace.c
ptrace: make ptrace() fail if the tracee changed its pid unexpectedly
2021-05-26 12:05:15 +02:00
range.c
reboot.c
reboot: fix overflow parsing reboot cpu number
2020-11-18 19:20:30 +01:00
relay.c
kernel/relay.c: fix memleak on destroy relay channel
2020-08-26 10:40:51 +02:00
resource.c
/dev/mem: Revoke mappings when a driver claims the region
2020-06-24 17:50:35 +02:00
rseq.c
seccomp.c
seccomp: Add missing return in non-void function
2021-03-04 10:26:45 +01:00
signal.c
ptrace: fix task_join_group_stop() for the case when current is traced
2020-11-10 12:37:24 +01:00
smp.c
smp: Fix smp_call_function_single_async prototype
2021-05-14 09:44:33 +02:00
smpboot.c
kthread: Extract KTHREAD_IS_PER_CPU
2021-02-07 15:35:49 +01:00
smpboot.h
softirq.c
stackleak.c
stacktrace.c
stop_machine.c
sys.c
kernel/sys.c: avoid copying possible padding bytes in copy_to_user
2020-10-01 13:17:23 +02:00
sys_ni.c
sysctl-test.c
kernel/sysctl-test: Add null pointer test for sysctl.c:proc_dointvec()
2020-10-01 13:17:10 +02:00
sysctl.c
sysctl.c: fix underflow value setting risk in vm_table
2021-03-17 17:03:45 +01:00
sysctl_binary.c
task_work.c
taskstats.c
taskstats: fix data-race
2020-01-09 10:19:54 +01:00
test_kprobes.c
torture.c
tracepoint.c
tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing
2021-07-14 16:53:08 +02:00
tsacct.c
ucount.c
uid16.c
uid16.h
umh.c
usermodehelper: reset umask to default before executing user process
2020-10-14 10:32:58 +02:00
up.c
smp: Fix smp_call_function_single_async prototype
2021-05-14 09:44:33 +02:00
user-return-notifier.c
user.c
user_namespace.c
utsname.c
utsname_sysctl.c
watchdog.c
watchdog/softlockup: Enforce that timestamp is valid on boot
2020-02-24 08:36:52 +01:00
watchdog_hld.c
workqueue.c
workqueue: fix UAF in pwq_unbound_release_workfn()
2021-07-31 08:19:37 +02:00
workqueue_internal.h