Christian Brauner
6b65c268df
sysctl: handle overflow for file-max
...
[ Upstream commit 32a5ad9c22852e6bd9e74bdec5934ef9d1480bc5 ]
Currently, when writing
echo 18446744073709551616 > /proc/sys/fs/file-max
/proc/sys/fs/file-max will overflow and be set to 0. That quickly
crashes the system.
This commit sets the max and min value for file-max. The max value is
set to long int. Any higher value cannot currently be used as the
percpu counters are long ints and not unsigned integers.
Note that the file-max value is ultimately parsed via
__do_proc_doulongvec_minmax(). This function does not report error when
min or max are exceeded. Which means if a value largen that long int is
written userspace will not receive an error instead the old value will be
kept. There is an argument to be made that this should be changed and
__do_proc_doulongvec_minmax() should return an error when a dedicated min
or max value are exceeded. However this has the potential to break
userspace so let's defer this to an RFC patch.
Link: http://lkml.kernel.org/r/20190107222700.15954-3-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Waiman Long <longman@redhat.com>
[christian@brauner.io: v4]
Link: http://lkml.kernel.org/r/20190210203943.8227-3-christian@brauner.io
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-05 22:29:06 +02:00
..
bpf
bpf: check pending signals while verifying programs
2018-12-21 14:11:38 +01:00
configs
config: android: enable CONFIG_SECCOMP
2016-10-11 15:06:32 -07:00
debug
kdb: use memmove instead of overlapping memcpy
2018-12-08 13:05:05 +01:00
events
perf core: Fix perf_proc_update_handler() bug
2019-03-13 14:04:55 -07:00
gcov
gcov: support GCC 7.1
2017-09-02 07:07:53 +02:00
irq
genirq: Fix race on spurious interrupt detection
2018-11-13 11:17:01 -08:00
livepatch
livepatch/module: make TAINT_LIVEPATCH module-specific
2016-08-26 14:42:08 +02:00
locking
locking/lockdep: Add debug_locks check in __lock_downgrade()
2019-03-27 14:13:03 +09:00
power
PM / sleep: wakeup: Fix build error caused by missing SRCU support
2018-09-09 20:01:23 +02:00
printk
printk: Fix panic caused by passing log_buf_len to command line
2018-11-13 11:17:01 -08:00
rcu
rcu: Do RCU GP kthread self-wakeup from softirq and interrupt
2019-03-23 13:19:53 +01:00
sched
sched/core: Allow __sched_setscheduler() in interrupts when PI is not used
2018-12-01 09:44:25 +01:00
time
timekeeping: Use proper seqcount initializer
2019-02-12 19:44:54 +01:00
trace
tracing: kdb: Fix ftdump to not sleep
2019-04-05 22:29:05 +02:00
.gitignore
acct.c
kernel/acct.c: fix the acct->needcheck check in check_free_space()
2018-01-10 09:29:51 +01:00
async.c
kernel/async.c: revert "async: simplify lowest_in_progress()"
2018-02-17 13:21:18 +01:00
audit.c
audit: return on memory error to avoid null pointer dereference
2018-05-30 07:50:49 +02:00
audit.h
Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit
2016-07-29 17:54:17 -07:00
audit_fsnotify.c
audit_tree.c
audit: cleanup prune_tree_thread
2016-04-04 09:46:47 -04:00
audit_watch.c
audit: fix use-after-free in audit_add_watch
2018-09-26 08:36:37 +02:00
auditfilter.c
audit: allow not equal op for audit by executable
2018-08-03 07:55:25 +02:00
auditsc.c
audit: allow not equal op for audit by executable
2018-08-03 07:55:25 +02:00
backtracetest.c
bounds.c
kbuild: fix kernel/bounds.c 'W=1' warning
2018-11-13 11:16:57 -08:00
capability.c
ptrace: Capture the ptracer's creds not PT_PTRACE_CAP
2017-01-06 10:40:13 +01:00
cgroup.c
cgroup: Fix deadlock in cpu hotplug path
2018-10-13 09:18:56 +02:00
cgroup_freezer.c
cgroup_pids.c
cgroup/pids: remove spurious suspicious RCU usage warning
2017-03-26 13:05:58 +02:00
compat.c
configs.c
context_tracking.c
cpu.c
cpu/hotplug: Prevent crash when CPU bringup fails on CONFIG_HOTPLUG_CPU=n
2019-04-03 06:24:19 +02:00
cpu_pm.c
cpuset.c
sched/cpuset/pm: Fix cpuset vs. suspend-resume bugs
2017-10-12 11:51:25 +02:00
crash_dump.c
cred.c
cred: Reject inodes with invalid ids in set_create_file_as()
2016-06-30 18:05:09 -05:00
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c
kernel/exit.c: release ptraced tasks before zap_pid_ns_processes
2019-02-06 17:33:29 +01:00
extable.c
kernel/extable.c: mark core_kernel_text notrace
2017-07-21 07:42:21 +02:00
fork.c
fork: record start_time late
2019-01-13 10:03:51 +01:00
freezer.c
freezer, oom: check TIF_MEMDIE on the correct task
2016-07-28 16:07:41 -07:00
futex.c
futex: Ensure that futex address is aligned in handle_futex_death()
2019-03-27 14:13:03 +09:00
futex_compat.c
groups.c
kernel: make groups_sort calling a responsibility group_info allocators
2018-01-10 09:29:52 +01:00
hung_task.c
kernel/hung_task.c: break RCU locks based on jiffies
2019-02-12 19:44:59 +01:00
irq_work.c
jump_label.c
jump_label: Invoke jump_label_test() via early_initcall()
2017-12-14 09:28:24 +01:00
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c
kcov: ensure irq code sees a valid area
2018-08-03 07:55:12 +02:00
kexec.c
kexec: allow architectures to override boot mapping
2016-08-02 19:35:27 -04:00
kexec_core.c
objtool, x86: Add several functions and files to the objtool whitelist
2018-06-05 10:28:57 +02:00
kexec_file.c
kexec: fix double-free when failing to relocate the purgatory
2016-09-01 17:52:01 -07:00
kexec_internal.h
kmod.c
kprobes.c
kprobes: Return error if we fail to reuse kprobe instead of BUG_ON()
2018-11-13 11:16:50 -08:00
ksysfs.c
kexec: add a kexec_crash_loaded() function
2016-08-02 19:35:30 -04:00
kthread.c
kthread, tracing: Don't expose half-written comm when creating kthreads
2018-08-03 07:55:12 +02:00
latencytop.c
Makefile
kernel/watchdog.c: move hardlockup detector to separate file
2017-06-17 06:41:57 +02:00
membarrier.c
Fix: Disable sys_membarrier when nohz_full is enabled
2017-03-12 06:41:45 +01:00
memremap.c
mm, devm_memremap_pages: kill mapping "System RAM" support
2019-01-13 10:03:51 +01:00
module-internal.h
module.c
module: exclude SHN_UNDEF symbols from kallsyms api
2018-10-03 17:01:48 -07:00
module_signing.c
KEYS: Move the point of trust determination to __key_link()
2016-04-11 22:43:43 +01:00
notifier.c
nsproxy.c
padata.c
padata: free correct variable
2017-05-20 14:28:40 +02:00
panic.c
panic: avoid deadlocks in re-entrant console drivers
2018-12-29 13:40:16 +01:00
params.c
pid.c
pidns: disable pid allocation if pid_ns_prepare_proc() is failed in alloc_pid()
2018-04-13 19:47:53 +02:00
pid_namespace.c
pid_ns: Sleep in TASK_INTERRUPTIBLE in zap_pid_ns_processes
2017-05-25 15:44:38 +02:00
profile.c
profile: Convert to hotplug state machine
2016-07-15 10:41:42 +02:00
ptrace.c
ptrace: Properly initialize ptracer_cred on fork
2017-06-14 15:05:54 +02:00
range.c
reboot.c
relay.c
kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE
2018-05-30 07:50:29 +02:00
resource.c
resource: fix integer overflow at reallocation
2018-04-24 09:34:09 +02:00
seccomp.c
seccomp: Move speculation migitation control to arch code
2018-05-22 16:58:02 +02:00
signal.c
signal: Restore the stop PTRACE_EVENT_EXIT
2019-02-20 10:18:33 +01:00
smp.c
cpu/hotplug: Fix SMT supported evaluation
2018-08-15 18:14:53 +02:00
smpboot.c
kthread/smpboot: do not park in kthread_create_on_cpu()
2016-10-11 15:06:33 -07:00
smpboot.h
softirq.c
Mark HI and TASKLET softirq synchronous
2018-08-15 18:14:42 +02:00
stacktrace.c
stacktrace, lockdep: Fix address, newline ugliness
2017-02-14 15:25:42 -08:00
stop_machine.c
stop_machine: Use raw spinlocks
2018-08-03 07:55:24 +02:00
sys.c
sys: don't hold uts_sem while accessing userspace memory
2018-09-09 20:01:24 +02:00
sys_ni.c
x86/pkeys: Fix pkeys build breakage for some non-x86 arches
2016-09-13 14:41:36 +02:00
sysctl.c
sysctl: handle overflow for file-max
2019-04-05 22:29:06 +02:00
sysctl_binary.c
kernel/sysctl_binary.c: use generic UUID library
2016-05-20 17:58:30 -07:00
task_work.c
task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works
2016-08-02 19:35:02 -04:00
taskstats.c
taskstats: fix the length of cgroupstats_cmd_get_policy
2016-11-03 16:55:58 -04:00
test_kprobes.c
torture.c
torture: Convert torture_shutdown() to hrtimer
2016-08-22 10:01:49 -07:00
tracepoint.c
tracepoint: Do not warn on ENOMEM
2018-05-09 09:50:20 +02:00
tsacct.c
ucount.c
kernel/ucount.c: mark user_header with kmemleak_ignore()
2017-06-17 06:41:51 +02:00
uid16.c
kernel: make groups_sort calling a responsibility group_info allocators
2018-01-10 09:29:52 +01:00
up.c
smp: Add function to execute a function synchronously on a CPU
2016-09-05 13:52:39 +02:00
user-return-notifier.c
user.c
user_namespace.c
userns: move user access out of the mutex
2018-09-09 20:01:24 +02:00
utsname.c
Merge branch 'nsfs-ioctls' into HEAD
2016-09-22 20:00:36 -05:00
utsname_sysctl.c
sys: don't hold uts_sem while accessing userspace memory
2018-09-09 20:01:24 +02:00
watchdog.c
kernel/watchdog: prevent false hardlockup on overloaded system
2017-06-17 06:41:57 +02:00
watchdog_hld.c
kernel/watchdog: prevent false hardlockup on overloaded system
2017-06-17 06:41:57 +02:00
workqueue.c
workqueue: use put_device() instead of kfree()
2018-05-30 07:50:36 +02:00
workqueue_internal.h
workqueue: Fix NULL pointer dereference
2017-11-15 15:53:17 +01:00