Petr Mladek
e91c2518a5
livepatch: Initialize shadow variables safely by a custom callback
...
The existing API allows to pass a sample data to initialize the shadow
data. It works well when the data are position independent. But it fails
miserably when we need to set a pointer to the shadow structure itself.
Unfortunately, we might need to initialize the pointer surprisingly
often because of struct list_head. It is even worse because the list
might be hidden in other common structures, for example, struct mutex,
struct wait_queue_head.
For example, this was needed to fix races in ALSA sequencer. It required
to add mutex into struct snd_seq_client. See commit b3defb791b
("ALSA: seq: Make ioctls race-free") and commit d15d662e89
("ALSA: seq: Fix racy pool initializations")
This patch makes the API more safe. A custom constructor function and data
are passed to klp_shadow_*alloc() functions instead of the sample data.
Note that ctor_data are no longer a template for shadow->data. It might
point to any data that might be necessary when the constructor is called.
Also note that the constructor is called under klp_shadow_lock. It is
an internal spin_lock that synchronizes alloc() vs. get() operations,
see klp_shadow_get_or_alloc(). On one hand, this adds a risk of ABBA
deadlocks. On the other hand, it allows to do some operations safely.
For example, we could add the new structure into an existing list.
This must be done only once when the structure is allocated.
Reported-by: Nicolai Stange <nstange@suse.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-04-17 13:42:48 +02:00
..
bpf
Merge branch 'work.mqueue' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2018-01-30 18:32:21 -08:00
cgroup
string: drop __must_check from strscpy() and restore strscpy() usages in cgroup
2018-01-19 08:51:36 -08:00
configs
PM: Provide a config snippet for disabling PM
2017-12-04 15:14:48 +01:00
debug
signal: Simplify and fix kdb_send_sig
2018-01-03 18:01:08 -06:00
events
Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2018-01-30 17:58:07 -08:00
gcov
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
irq
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2018-01-29 16:47:21 -08:00
livepatch
livepatch: Initialize shadow variables safely by a custom callback
2018-04-17 13:42:48 +02:00
locking
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2018-01-30 10:44:56 -08:00
power
Merge branch 'for-4.16/block' of git://git.kernel.dk/linux-block
2018-01-29 11:51:49 -08:00
printk
Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2018-01-30 17:58:07 -08:00
rcu
SCSI misc on 20180131
2018-01-31 11:23:28 -08:00
sched
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2018-01-30 11:55:56 -08:00
time
Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2018-01-30 17:58:07 -08:00
trace
Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2018-01-30 17:58:07 -08:00
.gitignore
acct.c
kernel/acct.c: fix the acct->needcheck check in check_free_space()
2018-01-04 16:45:09 -08:00
async.c
audit.c
Audit: remove unused audit_log_secctx function
2017-11-10 16:08:47 -05:00
audit.h
audit/stable-4.15 PR 20171113
2017-11-15 13:28:48 -08:00
audit_fsnotify.c
audit_tree.c
Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
2017-11-14 14:08:20 -08:00
audit_watch.c
auditfilter.c
audit: filter PATH records keyed on filesystem magic
2017-11-10 16:08:56 -05:00
auditsc.c
audit/stable-4.15 PR 20171113
2017-11-15 13:28:48 -08:00
backtracetest.c
bounds.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
capability.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
compat.c
sched_rr_get_interval(): move compat to native, get rid of set_fs()
2017-09-20 00:30:57 -04:00
configs.c
context_tracking.c
cpu.c
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2017-12-31 12:30:34 -08:00
cpu_pm.c
crash_core.c
kdump: write correct address of mem_section into vmcoreinfo
2018-01-13 10:42:48 -08:00
crash_dump.c
cred.c
delayacct.c
delayacct: Account blkio completion on the correct task
2018-01-16 03:29:36 +01:00
dma.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
elfcore.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
exec_domain.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
exit.c
kernel/exit.c: export abort() to modules
2018-01-04 16:45:09 -08:00
extable.c
kprobes, x86/alternatives: Use text_mutex to protect smp_alt_modules
2017-11-07 12:20:09 +01:00
fork.c
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2017-12-23 11:53:04 -08:00
freezer.c
futex.c
futex: Fix OWNER_DEAD fixup
2018-01-24 09:58:18 +01:00
futex_compat.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
groups.c
kernel: make groups_sort calling a responsibility group_info allocators
2017-12-14 16:00:49 -08:00
hung_task.c
irq_work.c
irq/work: Improve the flag definitions
2018-01-08 19:43:15 +01:00
jump_label.c
sched/core: Fix cpu.max vs. cpuhotplug deadlock
2018-01-24 10:03:44 +01:00
kallsyms.c
kallsyms: take advantage of the new '%px' format
2017-11-29 10:30:13 -08:00
kcmp.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c
kcov: fix comparison callback signature
2017-12-14 16:00:48 -08:00
kexec.c
kexec_core.c
kexec_file.c
resource: Provide resource struct in resource walk callback
2017-11-07 15:35:57 +01:00
kexec_internal.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
kmod.c
kmod: move #ifdef CONFIG_MODULES wrapper to Makefile
2017-09-08 18:26:51 -07:00
kprobes.c
kprobes: Disable the jprobes APIs
2017-10-20 11:02:29 +02:00
ksysfs.c
kthread.c
treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts
2017-11-21 16:35:54 -08:00
latencytop.c
Makefile
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
memremap.c
memremap: add scheduling point to devm_memremap_pages
2017-10-03 17:54:25 -07:00
module-internal.h
module.c
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2018-01-29 19:08:02 -08:00
module_signing.c
notifier.c
nsproxy.c
padata.c
treewide: setup_timer() -> timer_setup()
2017-11-21 15:57:07 -08:00
panic.c
kernel/panic.c: add TAINT_AUX
2017-11-17 16:10:04 -08:00
params.c
kernel/params.c: improve STANDARD_PARAM_DEF readability
2017-10-03 17:54:26 -07:00
pid.c
init_task out-of-lining
2018-01-29 09:08:34 -08:00
pid_namespace.c
pid: remove pidhash
2017-11-17 16:10:04 -08:00
profile.c
ptrace.c
ptrace: Use copy_siginfo in setsiginfo and getsiginfo
2018-01-16 12:48:30 -06:00
range.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
reboot.c
kernel/reboot.c: add devm_register_reboot_notifier()
2017-11-17 16:10:04 -08:00
relay.c
ipc, kernel, mm: annotate ->poll() instances
2017-11-27 16:20:05 -05:00
resource.c
x86/mm, resource: Use PAGE_KERNEL protection for ioremap of memory pages
2017-11-07 15:35:58 +01:00
seccomp.c
signal: Replace memset(info,...) with clear_siginfo for clarity
2018-01-22 19:07:08 -06:00
signal.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
2018-01-31 13:02:18 -08:00
smp.c
smp/core: Use lockdep to assert IRQs are disabled/enabled
2017-11-08 11:13:50 +01:00
smpboot.c
watchdog/core, powerpc: Lock cpus across reconfiguration
2017-10-04 10:53:54 +02:00
smpboot.h
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
softirq.c
softirq: Eliminate cond_resched_rcu_qs() in favor of cond_resched()
2017-12-04 10:28:58 -08:00
stacktrace.c
stop_machine.c
sys.c
fix typo in assignment of fs default overflow gid
2017-12-14 16:01:45 -06:00
sys_ni.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
sysctl.c
kernel/sysctl.c: code cleanups
2017-11-17 16:10:03 -08:00
sysctl_binary.c
License cleanup: add SPDX GPL-2.0 license identifier to files with no license
2017-11-02 11:10:55 +01:00
task_work.c
locking/barriers: Convert users of lockless_dereference() to READ_ONCE()
2017-12-17 13:57:15 +01:00
taskstats.c
test_kprobes.c
kprobes: Disable the jprobes test code
2017-10-20 11:02:54 +02:00
torture.c
torture: Save a line in stutter_wait(): while -> for
2017-12-11 09:18:30 -08:00
tracepoint.c
tracepoint: Remove smp_read_barrier_depends() from comment
2017-12-04 10:52:56 -08:00
tsacct.c
ucount.c
uid16.c
kernel: make groups_sort calling a responsibility group_info allocators
2017-12-14 16:00:49 -08:00
umh.c
kernel/umh.c: optimize 'proc_cap_handler()'
2017-11-17 16:10:01 -08:00
up.c
user-return-notifier.c
user.c
userns: use union in {g,u}idmap struct
2017-10-31 17:22:58 -05:00
user_namespace.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2017-11-16 12:20:15 -08:00
utsname.c
utsname_sysctl.c
watchdog.c
Merge branch 'linus' into sched/core, to pick up fixes
2017-11-08 10:17:15 +01:00
watchdog_hld.c
Merge branch 'linus' into core/urgent, to pick up dependent commits
2017-11-04 08:53:04 +01:00
workqueue.c
Merge branch 'for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
2018-01-30 14:45:39 -08:00
workqueue_internal.h
Merge branch 'for-4.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
2017-11-06 12:26:49 -08:00