Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Alexei Starovoitov 557c0c6e7d bpf: convert stackmap to pre-allocation ... It was observed that calling bpf_get_stackid() from a kprobe inside slub or from spin_unlock causes similar deadlock as with hashmap, therefore convert stackmap to use pre-allocated memory. The call_rcu is no longer feasible mechanism, since delayed freeing causes bpf_get_stackid() to fail unpredictably when number of actual stacks is significantly less than user requested max_entries. Since elements are no longer freed into slub, we can push elements into freelist immediately and let them be recycled. However the very unlikley race between user space map_lookup() and program-side recycling is possible: cpu0 cpu1 ---- ---- user does lookup(stackidX) starts copying ips into buffer delete(stackidX) calls bpf_get_stackid() which recyles the element and overwrites with new stack trace To avoid user space seeing a partial stack trace consisting of two merged stack traces, do bucket = xchg(, NULL); copy; xchg(,bucket); to preserve consistent stack trace delivery to user space. Now we can move memset(,0) of left-over element value from critical path of bpf_get_stackid() into slow-path of user space lookup. Also disallow lookup() from bpf program, since it's useless and program shouldn't be messing with collected stack trace. Note that similar race between user space lookup and kernel side updates is also present in hashmap, but it's not a new race. bpf programs were always allowed to modify hash and array map elements while user space is copying them. Fixes: d5a3b1f691 ("bpf: introduce BPF_MAP_TYPE_STACK_TRACE") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>		2016-03-08 15:28:31 -05:00
..
bpf	bpf: convert stackmap to pre-allocation	2016-03-08 15:28:31 -05:00
configs
debug	module: use a structure to encapsulate layout.	2015-12-04 22:46:25 +01:00
events	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2016-03-08 12:34:12 -05:00
gcov	gcov: use within_module() helper.	2015-12-04 22:46:25 +01:00
irq	Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-01-31 14:48:58 -08:00
livepatch	livepatch: Cleanup module page permission changes	2015-12-04 22:51:07 +01:00
locking	Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-02-14 12:02:05 -08:00
power	PM: APM_EMULATION does not depend on PM	2016-01-27 23:20:14 +01:00
printk	kernel: printk: specify alignment for struct printk_log	2016-01-20 17:09:18 -08:00
rcu	Merge branches 'doc.2015.12.05a', 'exp.2015.12.07a', 'fixes.2015.12.07a', 'list.2015.12.04b' and 'torture.2015.12.05a' into HEAD	2015-12-07 17:02:54 -08:00
sched	sched/deadline: Fix trivial typo in printk() message	2016-02-17 10:02:00 +01:00
time	Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-01-31 15:49:06 -08:00
trace	bpf: prevent kprobe+bpf deadlocks	2016-03-08 15:28:30 -05:00
.gitignore	certs: add .gitignore to stop git nagging about x509_certificate_list	2015-10-21 15:18:35 +01:00
acct.c
async.c	async: export current_is_async()	2015-11-19 17:51:48 +01:00
audit.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security	2016-01-17 19:13:15 -08:00
audit.h	security: Make inode argument of inode_getsecid non-const	2015-12-24 11:09:39 -05:00
audit_fsnotify.c	wrappers for ->i_mutex access	2016-01-22 18:04:28 -05:00
audit_tree.c	audit: audit_tree_match can be boolean	2015-11-04 08:23:51 -05:00
audit_watch.c	wrappers for ->i_mutex access	2016-01-22 18:04:28 -05:00
auditfilter.c	audit: fix comment block whitespace	2015-11-04 08:23:51 -05:00
auditsc.c	security: Make inode argument of inode_getsecid non-const	2015-12-24 11:09:39 -05:00
backtracetest.c
bounds.c
capability.c
cgroup.c	cgroup: make sure a parent css isn't freed before its children	2016-01-22 10:42:58 -05:00
cgroup_freezer.c	cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends	2015-12-03 10:24:08 -05:00
cgroup_pids.c	cgroup_pids: fix a typo.	2015-12-14 14:54:37 -05:00
compat.c
configs.c
context_tracking.c	context_tracking: Switch to new static_branch API	2015-11-24 09:56:43 +01:00
cpu.c	kernel/cpu.c: make set_cpu_* static inlines	2016-01-20 17:09:18 -08:00
cpu_pm.c	kernel/cpu_pm: fix cpu_cluster_pm_exit comment	2015-09-03 02:42:20 +02:00
cpuset.c	cpuset: make mm migration asynchronous	2016-01-22 10:22:46 -05:00
crash_dump.c
cred.c	kmemcg: account certain kmem allocations to memcg	2016-01-14 16:00:49 -08:00
delayacct.c	kmemcg: account certain kmem allocations to memcg	2016-01-14 16:00:49 -08:00
dma.c
elfcore.c
exec_domain.c
exit.c	exit: remove unneeded declaration of exit_mm()	2016-01-20 17:09:18 -08:00
extable.c	kernel/extable.c: remove duplicated include	2015-09-10 13:29:01 -07:00
fork.c	mm: rework virtual memory accounting	2016-01-14 16:00:49 -08:00
freezer.c
futex.c	rtmutex: Make wait_lock irq safe	2016-01-26 11:08:35 +01:00
futex_compat.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
groups.c
hung_task.c
irq_work.c	treewide: Remove old email address	2015-11-23 09:44:58 +01:00
jump_label.c	treewide: Remove old email address	2015-11-23 09:44:58 +01:00
kallsyms.c
kcmp.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c	kexec: set KEXEC_TYPE_CRASH before sanity_check_segment_list()	2016-01-20 17:09:18 -08:00
kexec_core.c	kernel/kexec_core.c: use list_for_each_entry_safe in kimage_free_page_list	2016-01-20 17:09:18 -08:00
kexec_file.c	kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE	2016-01-20 17:09:18 -08:00
kexec_internal.h	kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE	2016-01-20 17:09:18 -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
ksysfs.c	rcu: Remove TINY_RCU bloat from pointless boot parameters	2015-12-07 16:59:37 -08:00
kthread.c	kernel/kthread.c:kthread_create_on_node(): clarify documentation	2015-09-04 16:54:41 -07:00
latencytop.c
Makefile	sys_membarrier(): system-wide memory barrier (generic, x86)	2015-09-11 15:21:34 -07:00
membarrier.c	sys_membarrier(): system-wide memory barrier (generic, x86)	2015-09-11 15:21:34 -07:00
memremap.c	Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm	2016-02-25 18:54:53 -08:00
module-internal.h
module.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching	2016-02-18 16:34:15 -08:00
module_signing.c	KEYS: Merge the type-specific data with the payload data	2015-10-21 15:18:36 +01:00
notifier.c
nsproxy.c
padata.c
panic.c	printk: do cond_resched() between lines while outputting to consoles	2016-01-16 11:17:25 -08:00
params.c	Nothing exciting, minor tweaks and cleanups.	2015-11-09 15:53:39 -08:00
pid.c	Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-01-31 15:44:04 -08:00
pid_namespace.c
profile.c	mm: rename alloc_pages_exact_node() to __alloc_pages_node()	2015-09-08 15:35:28 -07:00
ptrace.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
range.c
reboot.c	kexec: split kexec_load syscall from kexec core code	2015-09-10 13:29:01 -07:00
relay.c	wrappers for ->i_mutex access	2016-01-22 18:04:28 -05:00
resource.c	kernel/resource.c: fix muxed resource handling in __request_region()	2016-02-20 08:57:52 -08:00
seccomp.c	seccomp: always propagate NO_NEW_PRIVS on tsync	2016-01-27 07:38:25 -08:00
signal.c	signals: avoid random wakeups in sigsuspend()	2016-02-05 18:10:40 -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
stacktrace.c
stop_machine.c	kernel/stop_machine.c: remove CONFIG_SMP dependencies	2016-01-16 11:17:24 -08:00
sys.c	prctl: take mmap sem for writing to protect against others	2016-01-20 17:09:18 -08:00
sys_ni.c	vfs: add copy_file_range syscall and vfs helper	2015-12-01 14:00:53 -05:00
sysctl.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2016-01-22 10:24:03 -08:00
sysctl_binary.c
task_work.c	task_work: remove fifo ordering guarantee	2015-09-05 13:46:58 -07:00
taskstats.c
test_kprobes.c
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
uid16.c
up.c
user-return-notifier.c
user.c
user_namespace.c	kernel/*: switch to memdup_user_nul()	2016-01-04 10:27:55 -05:00
utsname.c
utsname_sysctl.c
watchdog.c	Merge branch 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq	2016-01-11 18:53:13 -08:00
workqueue.c	workqueue: handle NUMA_NO_NODE for unbound pool_workqueue lookup	2016-02-10 12:13:05 -05:00
workqueue_internal.h