linux/kernel
Xunlei Pang 4b97cecd54 kexec: introduce a protection mechanism for the crashkernel reserved memory
For the cases that some kernel (module) path stamps the crash reserved
memory(already mapped by the kernel) where has been loaded the second
kernel data, the kdump kernel will probably fail to boot when panic
happens (or even not happens) leaving the culprit at large, this is
unacceptable.

The patch introduces a mechanism for detecting such cases:

1) After each crash kexec loading, it simply marks the reserved memory
   regions readonly since we no longer access it after that.  When someone
   stamps the region, the first kernel will panic and trigger the kdump.
   The weak arch_kexec_protect_crashkres() is introduced to do the actual
   protection.

2) To allow multiple loading, once 1) was done we also need to remark
   the reserved memory to readwrite each time a system call related to
   kdump is made.  The weak arch_kexec_unprotect_crashkres() is introduced
   to do the actual protection.

The architecture can make its specific implementation by overriding
arch_kexec_protect_crashkres() and arch_kexec_unprotect_crashkres().

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Minfei Huang <mhuang@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 9b492cf580)
Signed-off-by: Alex Shi <alex.shi@linaro.org>
2017-10-25 11:23:52 +08:00
..
bpf bpf, inode: disallow userns mounts 2016-06-24 10:18:17 -07:00
configs kconfig: tinyconfig: provide whole choice blocks to avoid warnings 2016-09-24 10:07:42 +02:00
debug Merge tag 'v4.4.40' into linux-linaro-lsk-v4.4 2017-01-09 12:01:31 +08:00
events Merge tag 'v4.4.65' into linux-linaro-lsk-v4.4 2017-05-01 12:02:08 +08:00
gcov gcov: add support for GCC 5.1 2015-06-30 19:44:57 -07:00
irq genirq: Fix chained interrupt data ordering 2017-05-25 14:30:17 +02:00
livepatch livepatch: x86: fix relocation computation with kASLR 2015-11-11 17:36:04 +01:00
locking locking/rtmutex: Use READ_ONCE() in rt_mutex_owner() 2016-12-15 08:49:22 -08:00
power Merge tag 'v4.4.35' into linux-linaro-lsk-v4.4 2016-11-28 12:00:55 +08:00
printk printk: use rcuidle console tracepoint 2017-02-23 17:43:10 +01:00
rcu rcu: Fix soft lockup for rcu_nocb_kthread 2016-12-08 07:15:24 +01:00
sched sched/fair: Initialize throttle_count for new task-groups lazily 2017-05-25 14:30:12 +02:00
time tick/broadcast: Prevent NULL pointer dereference 2017-01-12 11:22:51 +01:00
trace tracing/kprobes: Enforce kprobes teardown after testing 2017-05-25 14:30:17 +02:00
.gitignore certs: add .gitignore to stop git nagging about x509_certificate_list 2015-10-21 15:18:35 +01:00
acct.c acct: check FMODE_CAN_WRITE 2015-04-11 22:27:55 -04:00
async.c kernel/async.c: switch to pr_foo() 2014-10-09 22:26:04 -04:00
audit_fsnotify.c audit: clean simple fsnotify implementation 2015-08-06 16:14:53 -04:00
audit_tree.c audit: audit_tree_match can be boolean 2015-11-04 08:23:51 -05:00
audit_watch.c audit: fix exe_file access in audit_exe_compare 2016-09-24 10:07:36 +02:00
audit.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
audit.h audit: audit_tree_match can be boolean 2015-11-04 08:23:51 -05:00
auditfilter.c audit: fix comment block whitespace 2015-11-04 08:23:51 -05:00
auditsc.c audit: fix a double fetch in audit_log_single_execve_arg() 2016-08-20 18:09:22 +02:00
backtracetest.c kernel/backtracetest.c: replace no level printk by pr_info() 2014-06-04 16:54:14 -07:00
bounds.c page-cgroup: get rid of NR_PCG_FLAGS 2014-08-08 15:57:18 -07:00
capability.c exec: Ensure mm->user_ns contains the execed files 2017-01-06 11:16:14 +01:00
cgroup_freezer.c cgroup: fix handling of multi-destination migration from subtree_control enabling 2015-12-03 10:18:21 -05:00
cgroup_pids.c cgroup_pids: don't account for the root cgroup 2015-12-03 10:18:21 -05:00
cgroup.c Merge tag 'v4.4.63' into linux-linaro-lsk-v4.4 2017-04-23 12:02:12 +08:00
compat.c compat: cleanup coding in compat_get_bitmap() and compat_put_bitmap() 2015-06-04 23:57:18 +02:00
configs.c
context_tracking.c context_tracking: avoid irq_save/irq_restore on guest entry and exit 2015-11-10 12:06:23 +01:00
cpu_pm.c kernel/cpu_pm: fix cpu_cluster_pm_exit comment 2015-09-03 02:42:20 +02:00
cpu.c stable-fixup: hotplug: fix unused function warning 2017-01-12 11:22:48 +01:00
cpuset.c cpuset: handle race between CPU hotplug and cpuset_hotplug_work 2016-10-07 15:23:40 +02:00
crash_dump.c crash_dump: Make is_kdump_kernel() accessible from modules 2014-08-25 15:42:19 -07:00
cred.c cred: Reject inodes with invalid ids in set_create_file_as() 2016-09-15 08:27:49 +02:00
delayacct.c delayacct: Remove braindamaged type conversions 2014-07-23 10:18:06 -07:00
dma.c
elfcore.c switch elf_core_write_extra_phdrs() to dump_emit() 2013-11-09 00:16:23 -05:00
exec_domain.c Remove rest of exec domains. 2015-04-12 21:03:31 +02:00
exit.c wait/ptrace: assume __WALL if the child is traced 2016-06-07 18:14:35 -07:00
extable.c kernel/extable.c: remove duplicated include 2015-09-10 13:29:01 -07:00
fork.c pid_ns: Fix race between setns'ed fork() and zap_pid_ns_processes() 2017-05-25 14:30:11 +02:00
freezer.c freezer: remove obsolete comments in __thaw_task() 2014-10-21 23:44:20 +02:00
futex_compat.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-02-25 12:01:16 -08:00
futex.c Merge tag 'v4.4.56' into linux-linaro-lsk-v4.4 2017-03-23 12:00:54 +08:00
groups.c kernel: conditionally support non-root users, groups and capabilities 2015-04-15 16:35:22 -07:00
hung_task.c kernel/hung_task.c: change hung_task.c to use for_each_process_thread() 2015-04-15 16:35:22 -07:00
irq_work.c treewide: Remove old email address 2015-11-23 09:44:58 +01:00
jump_label.c jump_labels: API for flushing deferred jump label updates 2017-01-19 20:17:19 +01:00
kallsyms.c kernel/kallsyms.c: use __seq_open_private() 2014-10-14 02:18:16 +02:00
kcmp.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-02-25 12:01:16 -08:00
Kconfig.freezer
Kconfig.hz kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS 2013-11-15 09:32:22 +09:00
Kconfig.locks locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS 2015-05-12 09:46:00 +02:00
Kconfig.preempt
kexec_core.c kexec: introduce a protection mechanism for the crashkernel reserved memory 2017-10-25 11:23:52 +08:00
kexec_file.c kexec: introduce a protection mechanism for the crashkernel reserved memory 2017-10-25 11:23:52 +08:00
kexec_internal.h kexec: split kexec_file syscall code to kexec_file.c 2015-09-10 13:29:01 -07:00
kexec.c kexec: introduce a protection mechanism for the crashkernel reserved memory 2017-10-25 11:23:52 +08:00
kmod.c kmod: don't run async usermode helper as a child of kworker thread 2015-10-23 17:55:10 +09:00
kprobes.c tracing/kprobes: Enforce kprobes teardown after testing 2017-05-25 14:30:17 +02:00
ksysfs.c kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00
kthread.c cgroup, kthread: close race window where new kthreads can be migrated to non-root cgroups 2017-04-21 09:30:04 +02:00
latencytop.c kernel/latencytop.c: convert seq_printf to seq_puts 2014-06-04 16:54:15 -07:00
Makefile sys_membarrier(): system-wide memory barrier (generic, x86) 2015-09-11 15:21:34 -07:00
membarrier.c Fix: Disable sys_membarrier when nohz_full is enabled 2017-03-12 06:37:26 +01:00
memremap.c mm: fix devm_memremap_pages crash, use mem_hotplug_{begin, done} 2017-01-19 20:17:18 +01:00
module_signing.c KEYS: Merge the type-specific data with the payload data 2015-10-21 15:18:36 +01:00
module-internal.h
module.c module: Invalidate signatures on force-loaded modules 2016-08-20 18:09:27 +02:00
notifier.c Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-09-01 08:40:25 -07:00
nsproxy.c bury struct proc_ns in fs/proc 2014-12-04 14:34:54 -05:00
padata.c padata: free correct variable 2017-05-20 14:27:02 +02:00
panic.c printk: do cond_resched() between lines while outputting to consoles 2016-02-17 12:30:57 -08:00
params.c Nothing exciting, minor tweaks and cleanups. 2015-11-09 15:53:39 -08:00
pid_namespace.c pid_ns: Sleep in TASK_INTERRUPTIBLE in zap_pid_ns_processes 2017-05-25 14:30:11 +02:00
pid.c pidns: fix NULL dereference in __task_pid_nr_ns() 2015-11-24 12:03:55 -08:00
profile.c mm: rename alloc_pages_exact_node() to __alloc_pages_node() 2015-09-08 15:35:28 -07:00
ptrace.c ptrace: fix PTRACE_LISTEN race corrupting task->state 2017-04-12 12:38:33 +02:00
range.c kernel: avoid overflow in cmp_range 2015-01-17 10:02:23 +13:00
reboot.c kexec: split kexec_load syscall from kexec core code 2015-09-10 13:29:01 -07:00
relay.c kernel/relay.c: use kvfree() in relay_free_page_array() 2015-06-30 19:44:59 -07:00
resource.c kernel/resource.c: fix muxed resource handling in __request_region() 2016-03-03 15:07:29 -08:00
seccomp.c seccomp: always propagate NO_NEW_PRIVS on tsync 2016-03-03 15:07:25 -08:00
signal.c kernel/signal.c: unexport sigsuspend() 2015-11-20 16:17:32 -08:00
smp.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
smpboot.c stop_machine: Kill smp_hotplug_thread->pre_unpark, introduce stop_machine_unpark() 2015-10-20 10:23:55 +02:00
smpboot.h
softirq.c Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-02-09 15:24:03 -08:00
stacktrace.c stacktrace: introduce snprint_stack_trace for buffer output 2014-12-13 12:42:48 -08:00
stop_machine.c kernel: remove stop_machine() Kconfig dependency 2015-12-12 10:15:34 -08:00
sys_ni.c mm: mlock: add new mlock system call 2015-11-05 19:34:48 -08:00
sys.c prctl: take mmap sem for writing to protect against others 2016-02-25 12:01:25 -08:00
sysctl_binary.c fs/coredump: prevent fsuid=0 dumps into user-controlled directories 2016-04-12 09:08:58 -07:00
sysctl.c mnt: Add a per mount namespace limit on the number of mounts 2017-04-30 05:49:28 +02:00
task_work.c task_work: remove fifo ordering guarantee 2015-09-05 13:46:58 -07:00
taskstats.c netlink: make nlmsg_end() and genlmsg_end() void 2015-01-18 01:03:45 -05:00
test_kprobes.c kernel/test_kprobes.c: use current logging functions 2014-08-08 15:57:18 -07:00
torture.c torture: Consolidate cond_resched_rcu_qs() into stutter_wait() 2015-10-06 11:25:01 -07:00
tracepoint.c tracepoint: Give priority to probes of tracepoints 2015-10-25 21:33:54 -04:00
tsacct.c sched: Make task->start_time nanoseconds based 2014-07-23 10:18:05 -07:00
uid16.c groups: Consolidate the setgroups permission checks 2014-12-05 17:19:27 -06:00
up.c smp: Rename __smp_call_function_single() to smp_call_function_single_async() 2014-02-24 14:47:15 -08:00
user_namespace.c capabilities: ambient capabilities 2015-09-04 16:54:41 -07:00
user-return-notifier.c scheduler: Replace __get_cpu_var with this_cpu_ptr 2014-08-26 13:45:45 -04:00
user.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2014-12-17 12:31:40 -08:00
utsname_sysctl.c sysctl: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:16 -07:00
utsname.c copy address of proc_ns_ops into ns_common 2014-12-04 14:34:47 -05:00
watchdog.c kernel/watchdog: use nmi registers snapshot in hardlockup handler 2017-01-06 11:16:16 +01:00
workqueue_internal.h workqueue: rename manager_mutex to attach_mutex 2014-05-20 10:59:32 -04:00
workqueue.c workqueue: fix rebind bound workers warning 2016-05-18 17:06:50 -07:00