linux-stable/kernel
John Fastabend a8e7a4e243 bpf: sockmap, fix leaking maps with attached but not detached progs
[ Upstream commit 3d9e952697 ]

When a program is attached to a map we increment the program refcnt
to ensure that the program is not removed while it is potentially
being referenced from sockmap side. However, if this same program
also references the map (this is a reasonably common pattern in
my programs) then the verifier will also increment the maps refcnt
from the verifier. This is to ensure the map doesn't get garbage
collected while the program has a reference to it.

So we are left in a state where the map holds the refcnt on the
program stopping it from being removed and releasing the map refcnt.
And vice versa the program holds a refcnt on the map stopping it
from releasing the refcnt on the prog.

All this is fine as long as users detach the program while the
map fd is still around. But, if the user omits this detach command
we are left with a dangling map we can no longer release.

To resolve this when the map fd is released decrement the program
references and remove any reference from the map to the program.
This fixes the issue with possibly dangling map and creates a
user side API constraint. That is, the map fd must be held open
for programs to be attached to a map.

Fixes: 174a79ff95 ("bpf: sockmap with sk redirect support")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-26 11:02:17 +02:00
..
bpf bpf: sockmap, fix leaking maps with attached but not detached progs 2018-04-26 11:02:17 +02:00
cgroup cgroup: fix rule checking for threaded mode switching 2018-03-28 18:24:37 +02:00
configs ANDROID: binder: add hwbinder,vndbinder to BINDER_DEVICES. 2017-08-22 18:43:23 -07:00
debug kdb: Fix handling of kallsyms_symbol_next() return value 2017-12-14 09:52:58 +01:00
events perf/core: Fix use-after-free in uprobe_perf_close() 2018-04-19 08:56:17 +02:00
gcov License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq genirq: Guard handle_bad_irq log messages 2018-03-03 10:24:31 +01:00
livepatch License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
locking locking/locktorture: Fix num reader/writer corner cases 2018-03-19 08:42:56 +01:00
power x86/power: Fix swsusp_arch_resume prototype 2018-04-26 11:02:16 +02:00
printk License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rcu rcu: Export init_rcu_head() and destroy_rcu_head() to GPL modules 2018-02-16 20:23:11 +01:00
sched sched: Stop resched_cpu() from sending IPIs to offline CPUs 2018-03-19 08:42:49 +01:00
time posix-timers: Protect posix clock array access against speculation 2018-03-28 18:24:46 +02:00
trace ring-buffer: Check if memory is available before allocation 2018-04-24 09:36:32 +02:00
.gitignore
acct.c kernel/acct.c: fix the acct->needcheck check in check_free_space() 2018-01-10 09:31:17 +01:00
async.c kernel/async.c: revert "async: simplify lowest_in_progress()" 2018-02-16 20:23:05 +01:00
audit.c audit: ensure that 'audit=1' actually enables audit for PID 1 2017-12-17 15:08:00 +01:00
audit.h ipc: mqueue: Replace timespec with timespec64 2017-09-03 20:21:24 -04:00
audit_fsnotify.c Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2017-05-03 11:05:15 -07:00
audit_tree.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
audit_watch.c audit/stable-4.13 PR 20170816 2017-08-16 16:48:34 -07:00
auditfilter.c audit: kernel generated netlink traffic should have a portid of 0 2017-05-02 10:16:05 -04:00
auditsc.c Merge branch 'work.ipc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 17:37:26 -07:00
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 semtimedop(): move compat to native 2017-07-15 20:46:47 -04:00
configs.c
context_tracking.c
cpu.c timers: Reinitialize per cpu bases on hotplug 2018-01-02 20:31:15 +01:00
cpu_pm.c PM / CPU: replace raw_notifier with atomic_notifier 2017-07-31 13:09:49 +02:00
crash_core.c kdump: write correct address of mem_section into vmcoreinfo 2018-01-17 09:45:27 +01:00
crash_dump.c
cred.c doc: ReSTify credentials.txt 2017-05-18 10:30:19 -06:00
delayacct.c delayacct: Account blkio completion on the correct task 2018-01-23 19:58:13 +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 2018-02-13 10:19:49 +01:00
extable.c extable: Enable RCU if it is not watching in kernel_text_address() 2017-09-23 16:50:20 -04:00
fork.c kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK 2018-02-22 15:42:23 +01:00
freezer.c
futex.c futex: Fix OWNER_DEAD fixup 2018-02-03 17:38:47 +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 2017-12-20 10:10:18 +01:00
hung_task.c kernel/hung_task.c: defer showing held locks 2017-05-08 17:15:10 -07:00
irq_work.c
jump_label.c jump_label: Invoke jump_label_test() via early_initcall() 2017-12-14 09:53:13 +01:00
kallsyms.c kernel/kallsyms.c: replace all_var with IS_ENABLED(CONFIG_KALLSYMS_ALL) 2017-07-10 16:32:34 -07:00
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: detect double association with a single task 2018-02-25 11:07:50 +01:00
kexec.c kdump: protect vmcoreinfo data under the crash memory 2017-07-12 16:26:00 -07:00
kexec_core.c x86/mm, kexec: Allow kexec to be used with SME 2017-07-18 11:38:04 +02:00
kexec_file.c kexec_file: adjust declaration of kexec_purgatory 2017-07-12 16:26:02 -07:00
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: Use synchronize_rcu_tasks() for optprobe with CONFIG_PREEMPT=y 2017-12-10 13:40:40 +01:00
ksysfs.c kexec: move vmcoreinfo out of the kernel's .bss section 2017-07-12 16:25:59 -07:00
kthread.c kernel/kthread.c: kthread_worker: don't hog the cpu 2017-08-31 16:33:15 -07:00
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 mm: Fix memory size alignment in devm_memremap_pages_release() 2018-02-22 15:42:27 +01:00
module-internal.h
module.c module/retpoline: Warn about missing retpoline in module 2018-02-07 11:12:18 -08:00
module_signing.c
notifier.c
nsproxy.c
padata.c padata: Avoid nested calls to cpus_read_lock() in pcrypt_init_padata() 2017-05-26 10:10:37 +02:00
panic.c locking/refcounts, x86/asm: Implement fast refcount overflow protection 2017-08-17 10:40:26 +02:00
params.c kernel/params.c: improve STANDARD_PARAM_DEF readability 2017-10-03 17:54:26 -07:00
pid.c pids: make task_tgid_nr_ns() safe 2017-08-21 12:47:31 -07:00
pid_namespace.c userns,pidns: Verify the userns for new pid namespaces 2017-07-20 07:43:58 -05:00
profile.c
ptrace.c signal: Remove kernel interal si_code magic 2017-07-24 14:30:28 -05:00
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
relay.c kernel/relay.c: revert "kernel/relay.c: fix potential memory leak" 2018-02-16 20:23:05 +01:00
resource.c resource: fix integer overflow at reallocation 2018-04-24 09:36:22 +02:00
seccomp.c locking/barriers: Convert users of lockless_dereference() to READ_ONCE() 2017-12-25 14:26:21 +01:00
signal.c kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK 2018-02-22 15:42:23 +01:00
smp.c treewide: make "nr_cpu_ids" unsigned 2017-09-08 18:26:48 -07:00
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 kmemcheck: rip it out 2018-02-22 15:42:24 +01:00
stacktrace.c
stop_machine.c stop_machine: Provide stop_machine_cpuslocked() 2017-05-26 10:10:36 +02:00
sys.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
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 kmemcheck: rip it out 2018-02-22 15:42:24 +01:00
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() 2017-12-25 14:26:21 +01:00
taskstats.c taskstats: add e/u/stime for TGID command 2017-05-08 17:15:12 -07:00
test_kprobes.c
torture.c torture: Fix typo suppressing CPU-hotplug statistics 2017-07-25 13:04:45 -07:00
tracepoint.c
tsacct.c
ucount.c
uid16.c kernel: make groups_sort calling a responsibility group_info allocators 2017-12-20 10:10:18 +01:00
umh.c kmod: split out umh code into its own file 2017-09-08 18:26:50 -07:00
up.c smp: Avoid using two cache lines for struct call_single_data 2017-08-29 15:14:38 +02:00
user-return-notifier.c
user.c
user_namespace.c userns,pidns: Verify the userns for new pid namespaces 2017-07-20 07:43:58 -05:00
utsname.c
utsname_sysctl.c
watchdog.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +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 workqueue: Allow retrieval of current task's work struct 2018-03-15 10:54:29 +01:00
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