linux/kernel
Daniel Thompson eadb2f47a3 lockdown: also lock down previous kgdb use
KGDB and KDB allow read and write access to kernel memory, and thus
should be restricted during lockdown.  An attacker with access to a
serial port (for example, via a hypervisor console, which some cloud
vendors provide over the network) could trigger the debugger so it is
important that the debugger respect the lockdown mode when/if it is
triggered.

Fix this by integrating lockdown into kdb's existing permissions
mechanism.  Unfortunately kgdb does not have any permissions mechanism
(although it certainly could be added later) so, for now, kgdb is simply
and brutally disabled by immediately exiting the gdb stub without taking
any action.

For lockdowns established early in the boot (e.g. the normal case) then
this should be fine but on systems where kgdb has set breakpoints before
the lockdown is enacted than "bad things" will happen.

CVE: CVE-2022-21499
Co-developed-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-05-24 11:29:34 -07:00
..
bpf rcu: Make the TASKS_RCU Kconfig option be selected 2022-04-20 16:52:58 -07:00
cgroup cgroup/cpuset: Remove cpus_allowed/mems_allowed setup in cpuset_init_smp() 2022-05-05 08:57:00 -10:00
configs x86/configs: Add x86 debugging Kconfig fragment plus docs 2022-04-06 19:56:29 +02:00
debug lockdown: also lock down previous kgdb use 2022-05-24 11:29:34 -07:00
dma dma-direct: avoid redundant memory sync for swiotlb 2022-04-14 06:30:39 +02:00
entry Locking changes in this cycle were: 2022-05-24 10:18:23 -07:00
events Perf events changes for this cycle were: 2022-05-24 10:59:38 -07:00
futex futex: Remove a PREEMPT_RT_FULL reference. 2022-05-13 12:36:51 +02:00
gcov gcov: Remove compiler version check 2021-12-02 17:25:21 +09:00
irq Updates for interrupt core and drivers: 2022-05-23 16:58:49 -07:00
kcsan kcsan: Use preemption model accessors 2022-04-05 10:24:42 +02:00
livepatch ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
locking locking/qrwlock: Change "queue rwlock" to "queued rwlock" 2022-05-11 16:27:04 +02:00
power for-5.18/block-2022-03-18 2022-03-21 16:48:55 -07:00
printk printk changes for 5.18 2022-03-23 10:54:27 -07:00
rcu Merge branch 'exp.2022.05.11a' into HEAD 2022-05-11 11:49:35 -07:00
sched Scheduler changes in this cycle were: 2022-05-24 11:11:13 -07:00
time Updates for timers and timekeeping core code: 2022-05-23 17:05:55 -07:00
trace Scheduler changes in this cycle were: 2022-05-24 11:11:13 -07:00
.gitignore
acct.c kernel: remove spurious blkdev.h includes 2021-10-18 06:17:01 -06:00
async.c Revert "module, async: async_synchronize_full() on module init iff async is used" 2022-02-03 11:20:34 -08:00
audit_fsnotify.c fsnotify: clarify contract for create event hooks 2021-10-27 12:32:34 +02:00
audit_tree.c audit: use struct_size() helper in kmalloc() 2021-12-14 17:39:42 -05:00
audit_watch.c \n 2021-11-06 16:43:20 -07:00
audit.c audit: improve audit queue handling when "audit=1" on cmdline 2022-01-25 13:22:51 -05:00
audit.h audit: log AUDIT_TIME_* records only from rules 2022-02-22 13:51:40 -05:00
auditfilter.c audit/stable-5.17 PR 20220110 2022-01-11 13:08:21 -08:00
auditsc.c audit,io_uring,io-wq: call __audit_uring_exit for dummy contexts 2022-05-17 15:03:36 -04:00
backtracetest.c
bounds.c
capability.c xfs: don't generate selinux audit messages for capability testing 2022-03-09 10:32:06 -08:00
cfi.c cfi: Use rcu_read_{un}lock_sched_notrace 2021-08-11 13:11:12 -07:00
compat.c arch: remove compat_alloc_user_space 2021-09-08 15:32:35 -07:00
configs.c
context_tracking.c
cpu_pm.c PM: cpu: Make notifier chain use a raw_spinlock_t 2021-08-16 18:55:32 +02:00
cpu.c Intel Trust Domain Extensions 2022-05-23 17:51:12 -07:00
crash_core.c kdump: return -ENOENT if required cmdline option does not exist 2022-05-07 19:54:33 +01:00
crash_dump.c
cred.c x86: Mark __invalid_creds() __noreturn 2022-03-15 10:32:44 +01:00
delayacct.c delayacct: track delays from memory compact 2022-01-20 08:52:55 +02:00
dma.c
exec_domain.c
exit.c ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
extable.c lkdtm: Really write into kernel text in WRITE_KERN 2022-02-16 23:25:12 +11:00
fail_function.c
fork.c - Add Raptor Lake to the set of CPU models which support splitlock 2022-05-23 19:24:47 -07:00
freezer.c
gen_kheaders.sh
groups.c
hung_task.c hung_task: move hung_task sysctl interface to hung_task.c 2022-01-22 08:33:34 +02:00
iomem.c
irq_work.c irq_work: use kasan_record_aux_stack_noalloc() record callstack 2022-04-15 14:49:55 -07:00
jump_label.c jump_label: Fix jump_label_text_reserved() vs __init 2021-07-05 10:46:20 +02:00
kallsyms.c kallsyms: Skip the name search for empty string 2022-03-17 20:17:18 -07:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks locking/rwlock: Provide RT variant 2021-08-17 17:50:51 +02:00
Kconfig.preempt Revert "signal, x86: Delay calling signals in atomic on RT enabled kernels" 2022-03-31 10:36:55 +02:00
kcov.c kcov: don't generate a warning on vm_insert_page()'s failure 2022-04-21 20:01:10 -07:00
kexec_core.c ELF: Remove elf_core_copy_kernel_regs() 2022-04-14 14:08:26 +02:00
kexec_elf.c
kexec_file.c memblock: add MEMBLOCK_DRIVER_MANAGED to mimic IORESOURCE_SYSRAM_DRIVER_MANAGED 2021-11-06 13:30:42 -07:00
kexec_internal.h
kexec.c kexec: avoid compat_alloc_user_space 2021-09-08 15:32:34 -07:00
kheaders.c
kmod.c
kprobes.c kprobes: Fix KRETPROBES when CONFIG_KRETPROBE_ON_RETHOOK is set 2022-04-26 16:09:36 +02:00
ksysfs.c kernel/ksysfs.c: use helper macro __ATTR_RW 2022-03-23 19:00:33 -07:00
kthread.c kthread: unexport kthread_blkcg 2022-05-02 14:06:20 -06:00
latencytop.c
Makefile static_call: Don't make __static_call_return0 static 2022-04-05 09:59:38 +02:00
module_decompress.c module: fix building with sysfs disabled 2022-02-16 12:51:32 -08:00
module_signature.c
module_signing.c
module-internal.h module: add in-kernel support for decompressing 2022-01-11 18:45:02 -08:00
module.c NFSD: Remove svc_serv_ops::svo_module 2022-02-28 10:26:40 -05:00
notifier.c notifier: Return an error when a callback has already been registered 2021-12-29 10:37:33 +01:00
nsproxy.c memcg: enable accounting for new namesapces and struct nsproxy 2021-09-03 09:58:12 -07:00
padata.c padata: replace cpumask_weight with cpumask_empty in padata.c 2022-01-31 11:21:46 +11:00
panic.c panic: move panic_print before kmsg dumpers 2022-03-23 19:00:35 -07:00
params.c kobject: remove kset from struct kset_uevent_ops callbacks 2021-12-28 11:26:18 +01:00
pid_namespace.c memcg: enable accounting for new namesapces and struct nsproxy 2021-09-03 09:58:12 -07:00
pid.c pid: add pidfd_get_task() helper 2021-10-14 13:29:18 +02:00
profile.c exit: Remove profile_handoff_task 2022-01-08 12:43:57 -06:00
ptrace.c ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE 2022-03-22 13:06:05 -05:00
range.c
reboot.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2021-11-12 11:53:16 -08:00
regset.c
relay.c
resource_kunit.c
resource.c kernel/resource: fix kfree() of bootmem memory again 2022-03-23 19:00:35 -07:00
rseq.c rseq: Remove broken uapi field layout on 32-bit little endian 2022-02-02 13:11:34 +01:00
scftorture.c scftorture: Fix distribution of short handler delays 2022-04-11 17:07:29 -07:00
scs.c kasan, vmalloc: only tag normal vmalloc allocations 2022-03-24 19:06:48 -07:00
seccomp.c ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
signal.c signal: Deliver SIGTRAP on perf event asynchronously if blocked 2022-04-22 12:14:05 +02:00
smp.c Scheduler changes in this cycle were: 2022-05-24 11:11:13 -07:00
smpboot.c cpu/hotplug: Allow the CPU in CPU_UP_PREPARE state to be brought up again. 2022-04-12 14:13:01 +02:00
smpboot.h
softirq.c smp: Make softirq handling RT safe in flush_smp_call_function_queue() 2022-05-01 10:03:43 +02:00
stackleak.c gcc-plugins/stackleak: Use noinstr in favor of notrace 2022-02-03 17:02:21 -08:00
stacktrace.c uaccess: remove CONFIG_SET_FS 2022-02-25 09:36:06 +01:00
static_call_inline.c static_call: Don't make __static_call_return0 static 2022-04-05 09:59:38 +02:00
static_call.c static_call: Don't make __static_call_return0 static 2022-04-05 09:59:38 +02:00
stop_machine.c Scheduler changes in this cycle were: 2022-05-24 11:11:13 -07:00
sys_ni.c mm/mempolicy: wire up syscall set_mempolicy_home_node 2022-01-15 16:30:30 +02:00
sys.c arm64/sme: Implement vector length configuration prctl()s 2022-04-22 18:50:54 +01:00
sysctl-test.c kernel/sysctl-test: Remove some casts which are no-longer required 2021-06-23 16:41:24 -06:00
sysctl.c timers: Move timer sysctl into the timer code 2022-04-10 12:38:45 +02:00
task_work.c task_work: allow TWA_SIGNAL without a rescheduling IPI 2022-04-30 08:39:32 -06:00
taskstats.c taskstats: remove unneeded dead assignment 2022-03-23 19:00:35 -07:00
torture.c torture: Wake up kthreads after storing task_struct pointer 2022-02-01 17:24:39 -08:00
tracepoint.c tracepoint: Fix kerneldoc comments 2021-08-16 11:39:51 -04:00
tsacct.c taskstats: Cleanup the use of task->exit_code 2022-01-08 12:43:57 -06:00
ucount.c ucounts: Handle wrapping in is_ucounts_overlimit 2022-02-17 09:11:57 -06:00
uid16.c
uid16.h
umh.c
up.c
user_namespace.c ucounts: Fix systemd LimitNPROC with private users regression 2022-02-25 10:40:14 -06:00
user-return-notifier.c
user.c fs/epoll: use a per-cpu counter for user's watches count 2021-09-08 11:50:27 -07:00
usermode_driver.c Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:41:14 -07:00
utsname_sysctl.c
utsname.c
watch_queue.c watch_queue: Free the page array when watch_queue is dismantled 2022-04-02 10:37:39 -07:00
watchdog_hld.c
watchdog.c sched/isolation: Use single feature type while referring to housekeeping cpumask 2022-02-16 15:57:55 +01:00
workqueue_internal.h workqueue: Assign a color to barrier work items 2021-08-17 07:49:10 -10:00
workqueue.c Merge branch 'for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 2022-03-23 12:40:51 -07:00