ipc: fix memleak if msg_init_ns failed in create_ipc_ns

Percpu memory allocation may failed during create_ipc_ns however this
fail is not handled properly since ipc sysctls and mq sysctls is not
rel

ipc: fix memleak if msg_init_ns failed in create_ipc_ns

Percpu memory allocation may failed during create_ipc_ns however this
fail is not handled properly since ipc sysctls and mq sysctls is not
released properly. Fix this by release these two resource when failure.

Here is the kmemleak stack when percpu failed:

unreferenced object 0xffff88819de2a600 (size 512):
comm "shmem_2nstest", pid 120711, jiffies 4300542254
hex dump (first 32 bytes):
60 aa 9d 84 ff ff ff ff fc 18 48 b2 84 88 ff ff `.........H.....
04 00 00 00 a4 01 00 00 20 e4 56 81 ff ff ff ff ........ .V.....
backtrace (crc be7cba35):
[<ffffffff81b43f83>] __kmalloc_node_track_caller_noprof+0x333/0x420
[<ffffffff81a52e56>] kmemdup_noprof+0x26/0x50
[<ffffffff821b2f37>] setup_mq_sysctls+0x57/0x1d0
[<ffffffff821b29cc>] copy_ipcs+0x29c/0x3b0
[<ffffffff815d6a10>] create_new_namespaces+0x1d0/0x920
[<ffffffff815d7449>] copy_namespaces+0x2e9/0x3e0
[<ffffffff815458f3>] copy_process+0x29f3/0x7ff0
[<ffffffff8154b080>] kernel_clone+0xc0/0x650
[<ffffffff8154b6b1>] __do_sys_clone+0xa1/0xe0
[<ffffffff843df8ff>] do_syscall_64+0xbf/0x1c0
[<ffffffff846000b0>] entry_SYSCALL_64_after_hwframe+0x4b/0x53

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 72d1e611082e ("ipc/msg: mitigate the lock contention with percpu counter")
Signed-off-by: Ma Wupeng <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

ipc,namespace: batch free ipc_namespace structures

Instead of waiting for an RCU grace period between each ipc_namespace
structure that is being freed, wait an RCU grace period for every batch
of ip

ipc,namespace: batch free ipc_namespace structures

Instead of waiting for an RCU grace period between each ipc_namespace
structure that is being freed, wait an RCU grace period for every batch
of ipc_namespace structures.

Thanks to Al Viro for the suggestion of the helper function.

This speeds up the run time of the test case that allocates ipc_namespaces
in a loop from 6 minutes, to a little over 1 second:

real 0m1.192s
user 0m0.038s
sys 0m1.152s

Signed-off-by: Rik van Riel <[email protected]>
Reported-by: Chris Mason <[email protected]>
Tested-by: Giuseppe Scrivano <[email protected]>
Suggested-by: Al Viro <[email protected]>
Signed-off-by: Al Viro <[email protected]>

show more ...

ipc,namespace: make ipc namespace allocation wait for pending free

Currently the ipc namespace allocation will fail when there are
ipc_namespace structures pending to be freed. This results in the
s

ipc,namespace: make ipc namespace allocation wait for pending free

Currently the ipc namespace allocation will fail when there are
ipc_namespace structures pending to be freed. This results in the
simple test case below, as well as some real world workloads, to
get allocation failures even when the number of ipc namespaces in
actual use is way below the limit.

int main()
{
int i;

for (i = 0; i < 100000; i++) {
if (unshare(CLONE_NEWIPC) < 0)
error(EXIT_FAILURE, errno, "unshare");
}
}

Make the allocation of an ipc_namespace wait for pending frees,
so it will succeed.

real 6m19.197s
user 0m0.041s
sys 0m1.019s

Signed-off-by: Rik van Riel <[email protected]>
Reported-by: Chris Mason <[email protected]>
Signed-off-by: Al Viro <[email protected]>

show more ...

ipc/msg: mitigate the lock contention with percpu counter

The msg_bytes and msg_hdrs atomic counters are frequently updated when IPC
msg queue is in heavy use, causing heavy cache bounce and overhea

ipc/msg: mitigate the lock contention with percpu counter

The msg_bytes and msg_hdrs atomic counters are frequently updated when IPC
msg queue is in heavy use, causing heavy cache bounce and overhead.
Change them to percpu_counter greatly improve the performance. Since
there is one percpu struct per namespace, additional memory cost is
minimal. Reading of the count done in msgctl call, which is infrequent.
So the need to sum up the counts in each CPU is infrequent.

Apply the patch and test the pts/stress-ng-1.4.0
-- system v message passing (160 threads).

Score gain: 3.99x

CPU: ICX 8380 x 2 sockets
Core number: 40 x 2 physical cores
Benchmark: pts/stress-ng-1.4.0
-- system v message passing (160 threads)

[[email protected]: coding-style cleanups]
[[email protected]: avoid negative value by overflow in msginfo]
Link: https://lkml.kernel.org/r/[email protected]
[[email protected]: fix min() warnings]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jiebin Sun <[email protected]>
Reviewed-by: Tim Chen <[email protected]>
Cc: Alexander Mikhalitsyn <[email protected]>
Cc: Alexey Gladkov <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Dennis Zhou <[email protected]>
Cc: "Eric W . Biederman" <[email protected]>
Cc: Manfred Spraul <[email protected]>
Cc: Shakeel Butt <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Vasily Averin <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

ipc: Free mq_sysctls if ipc namespace creation failed

The problem that Dmitry Vyukov pointed out is that if setup_ipc_sysctls fails,
mq_sysctls must be freed before return.

executing program
BUG: m

ipc: Free mq_sysctls if ipc namespace creation failed

The problem that Dmitry Vyukov pointed out is that if setup_ipc_sysctls fails,
mq_sysctls must be freed before return.

executing program
BUG: memory leak
unreferenced object 0xffff888112fc9200 (size 512):
comm "syz-executor237", pid 3648, jiffies 4294970469 (age 12.270s)
hex dump (first 32 bytes):
ef d3 60 85 ff ff ff ff 0c 9b d2 12 81 88 ff ff ..`.............
04 00 00 00 a4 01 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff814b6eb3>] kmemdup+0x23/0x50 mm/util.c:129
[<ffffffff82219a9b>] kmemdup include/linux/fortify-string.h:456 [inline]
[<ffffffff82219a9b>] setup_mq_sysctls+0x4b/0x1c0 ipc/mq_sysctl.c:89
[<ffffffff822197f2>] create_ipc_ns ipc/namespace.c:63 [inline]
[<ffffffff822197f2>] copy_ipcs+0x292/0x390 ipc/namespace.c:91
[<ffffffff8127de7c>] create_new_namespaces+0xdc/0x4f0 kernel/nsproxy.c:90
[<ffffffff8127e89b>] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226
[<ffffffff8123f92e>] ksys_unshare+0x2fe/0x600 kernel/fork.c:3165
[<ffffffff8123fc42>] __do_sys_unshare kernel/fork.c:3236 [inline]
[<ffffffff8123fc42>] __se_sys_unshare kernel/fork.c:3234 [inline]
[<ffffffff8123fc42>] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3234
[<ffffffff845aab45>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff845aab45>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff8460006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

BUG: memory leak
unreferenced object 0xffff888112fd5f00 (size 256):
comm "syz-executor237", pid 3648, jiffies 4294970469 (age 12.270s)
hex dump (first 32 bytes):
00 92 fc 12 81 88 ff ff 00 00 00 00 01 00 00 00 ................
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff816fea1b>] kmalloc include/linux/slab.h:605 [inline]
[<ffffffff816fea1b>] kzalloc include/linux/slab.h:733 [inline]
[<ffffffff816fea1b>] __register_sysctl_table+0x7b/0x7f0 fs/proc/proc_sysctl.c:1344
[<ffffffff82219b7a>] setup_mq_sysctls+0x12a/0x1c0 ipc/mq_sysctl.c:112
[<ffffffff822197f2>] create_ipc_ns ipc/namespace.c:63 [inline]
[<ffffffff822197f2>] copy_ipcs+0x292/0x390 ipc/namespace.c:91
[<ffffffff8127de7c>] create_new_namespaces+0xdc/0x4f0 kernel/nsproxy.c:90
[<ffffffff8127e89b>] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226
[<ffffffff8123f92e>] ksys_unshare+0x2fe/0x600 kernel/fork.c:3165
[<ffffffff8123fc42>] __do_sys_unshare kernel/fork.c:3236 [inline]
[<ffffffff8123fc42>] __se_sys_unshare kernel/fork.c:3234 [inline]
[<ffffffff8123fc42>] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3234
[<ffffffff845aab45>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff845aab45>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff8460006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

BUG: memory leak
unreferenced object 0xffff888112fbba00 (size 256):
comm "syz-executor237", pid 3648, jiffies 4294970469 (age 12.270s)
hex dump (first 32 bytes):
78 ba fb 12 81 88 ff ff 00 00 00 00 01 00 00 00 x...............
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff816fef49>] kmalloc include/linux/slab.h:605 [inline]
[<ffffffff816fef49>] kzalloc include/linux/slab.h:733 [inline]
[<ffffffff816fef49>] new_dir fs/proc/proc_sysctl.c:978 [inline]
[<ffffffff816fef49>] get_subdir fs/proc/proc_sysctl.c:1022 [inline]
[<ffffffff816fef49>] __register_sysctl_table+0x5a9/0x7f0 fs/proc/proc_sysctl.c:1373
[<ffffffff82219b7a>] setup_mq_sysctls+0x12a/0x1c0 ipc/mq_sysctl.c:112
[<ffffffff822197f2>] create_ipc_ns ipc/namespace.c:63 [inline]
[<ffffffff822197f2>] copy_ipcs+0x292/0x390 ipc/namespace.c:91
[<ffffffff8127de7c>] create_new_namespaces+0xdc/0x4f0 kernel/nsproxy.c:90
[<ffffffff8127e89b>] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226
[<ffffffff8123f92e>] ksys_unshare+0x2fe/0x600 kernel/fork.c:3165
[<ffffffff8123fc42>] __do_sys_unshare kernel/fork.c:3236 [inline]
[<ffffffff8123fc42>] __se_sys_unshare kernel/fork.c:3234 [inline]
[<ffffffff8123fc42>] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3234
[<ffffffff845aab45>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff845aab45>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff8460006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

BUG: memory leak
unreferenced object 0xffff888112fbb900 (size 256):
comm "syz-executor237", pid 3648, jiffies 4294970469 (age 12.270s)
hex dump (first 32 bytes):
78 b9 fb 12 81 88 ff ff 00 00 00 00 01 00 00 00 x...............
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff816fef49>] kmalloc include/linux/slab.h:605 [inline]
[<ffffffff816fef49>] kzalloc include/linux/slab.h:733 [inline]
[<ffffffff816fef49>] new_dir fs/proc/proc_sysctl.c:978 [inline]
[<ffffffff816fef49>] get_subdir fs/proc/proc_sysctl.c:1022 [inline]
[<ffffffff816fef49>] __register_sysctl_table+0x5a9/0x7f0 fs/proc/proc_sysctl.c:1373
[<ffffffff82219b7a>] setup_mq_sysctls+0x12a/0x1c0 ipc/mq_sysctl.c:112
[<ffffffff822197f2>] create_ipc_ns ipc/namespace.c:63 [inline]
[<ffffffff822197f2>] copy_ipcs+0x292/0x390 ipc/namespace.c:91
[<ffffffff8127de7c>] create_new_namespaces+0xdc/0x4f0 kernel/nsproxy.c:90
[<ffffffff8127e89b>] unshare_nsproxy_namespaces+0x9b/0x120 kernel/nsproxy.c:226
[<ffffffff8123f92e>] ksys_unshare+0x2fe/0x600 kernel/fork.c:3165
[<ffffffff8123fc42>] __do_sys_unshare kernel/fork.c:3236 [inline]
[<ffffffff8123fc42>] __se_sys_unshare kernel/fork.c:3234 [inline]
[<ffffffff8123fc42>] __x64_sys_unshare+0x12/0x20 kernel/fork.c:3234
[<ffffffff845aab45>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff845aab45>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff8460006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

Reported-by: [email protected]
Signed-off-by: Alexey Gladkov <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Eric W. Biederman <[email protected]>

show more ...

ipc: Store ipc sysctls in the ipc namespace

The ipc sysctls are not available for modification inside the user
namespace. Following the mqueue sysctls, we changed the implementation
to be more usern

ipc: Store ipc sysctls in the ipc namespace

The ipc sysctls are not available for modification inside the user
namespace. Following the mqueue sysctls, we changed the implementation
to be more userns friendly.

So far, the changes do not provide additional access to files. This
will be done in a future patch.

Signed-off-by: Alexey Gladkov <[email protected]>
Link: https://lkml.kernel.org/r/be6f9d014276f4dddd0c3aa05a86052856c1c555.1644862280.git.legion@kernel.org
Signed-off-by: Eric W. Biederman <[email protected]>

show more ...

ipc: Store mqueue sysctls in the ipc namespace

Right now, the mqueue sysctls take ipc namespaces into account in a
rather hacky way. This works in most cases, but does not respect the
user namespace

ipc: Store mqueue sysctls in the ipc namespace

Right now, the mqueue sysctls take ipc namespaces into account in a
rather hacky way. This works in most cases, but does not respect the
user namespace.

Within the user namespace, the user cannot change the /proc/sys/fs/mqueue/*
parametres. This poses a problem in the rootless containers.

To solve this I changed the implementation of the mqueue sysctls just
like some other sysctls.

So far, the changes do not provide additional access to files. This will
be done in a future patch.

v3:
* Don't implemenet set_permissions to keep the current behavior.

v2:
* Fixed compilation problem if CONFIG_POSIX_MQUEUE_SYSCTL is not
specified.

Reported-by: kernel test robot <[email protected]>
Signed-off-by: Alexey Gladkov <[email protected]>
Link: https://lkml.kernel.org/r/b0ccbb2489119f1f20c737cf1930c3a9c4e4243a.1644862280.git.legion@kernel.org
Signed-off-by: Eric W. Biederman <[email protected]>

show more ...

memcg: enable accounting for new namesapces and struct nsproxy

Container admin can create new namespaces and force kernel to allocate up
to several pages of memory for the namespaces and its associa

memcg: enable accounting for new namesapces and struct nsproxy

Container admin can create new namespaces and force kernel to allocate up
to several pages of memory for the namespaces and its associated
structures.

Net and uts namespaces have enabled accounting for such allocations. It
makes sense to account for rest ones to restrict the host's memory
consumption from inside the memcg-limited container.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Vasily Averin <[email protected]>
Acked-by: Serge Hallyn <[email protected]>
Acked-by: Christian Brauner <[email protected]>
Acked-by: Kirill Tkhai <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: Andrei Vagin <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dmitry Safonov <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: "J. Bruce Fields" <[email protected]>
Cc: Jeff Layton <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Roman Gushchin <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vladimir Davydov <[email protected]>
Cc: Yutian Yang <[email protected]>
Cc: Zefan Li <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

ipc: Use generic ns_common::count

Switch over ipc namespaces to use the newly introduced common lifetime
counter.

Currently every namespace type has its own lifetime counter which is stored
in the

ipc: Use generic ns_common::count

Switch over ipc namespaces to use the newly introduced common lifetime
counter.

Currently every namespace type has its own lifetime counter which is stored
in the specific namespace struct. The lifetime counters are used
identically for all namespaces types. Namespaces may of course have
additional unrelated counters and these are not altered.

This introduces a common lifetime counter into struct ns_common. The
ns_common struct encompasses information that all namespaces share. That
should include the lifetime counter since its common for all of them.

It also allows us to unify the type of the counters across all namespaces.
Most of them use refcount_t but one uses atomic_t and at least one uses
kref. Especially the last one doesn't make much sense since it's just a
wrapper around refcount_t since 2016 and actually complicates cleanup
operations by having to use container_of() to cast the correct namespace
struct out of struct ns_common.

Having the lifetime counter for the namespaces in one place reduces
maintenance cost. Not just because after switching all namespaces over we
will have removed more code than we added but also because the logic is
more easily understandable and we indicate to the user that the basic
lifetime requirements for all namespaces are currently identical.

Signed-off-by: Kirill Tkhai <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Acked-by: Christian Brauner <[email protected]>
Link: https://lore.kernel.org/r/159644978697.604812.16592754423881032385.stgit@localhost.localdomain
Signed-off-by: Christian Brauner <[email protected]>

show more ...

ipc/namespace.c: use a work queue to free_ipc

the reason is to avoid a delay caused by the synchronize_rcu() call in
kern_umount() when the mqueue mount is freed.

the code:

#define _GNU_SOURCE

ipc/namespace.c: use a work queue to free_ipc

the reason is to avoid a delay caused by the synchronize_rcu() call in
kern_umount() when the mqueue mount is freed.

the code:

#define _GNU_SOURCE
#include <sched.h>
#include <error.h>
#include <errno.h>
#include <stdlib.h>

int main()
{
int i;

for (i = 0; i < 1000; i++)
if (unshare(CLONE_NEWIPC) < 0)
error(EXIT_FAILURE, errno, "unshare");
}

goes from

Command being timed: "./ipc-namespace"
User time (seconds): 0.00
System time (seconds): 0.06
Percent of CPU this job got: 0%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:08.05

to

Command being timed: "./ipc-namespace"
User time (seconds): 0.00
System time (seconds): 0.02
Percent of CPU this job got: 96%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:00.03

Signed-off-by: Giuseppe Scrivano <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Paul E. McKenney <[email protected]>
Reviewed-by: Waiman Long <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Manfred Spraul <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

nsproxy: add struct nsset

Add a simple struct nsset. It holds all necessary pieces to switch to a new
set of namespaces without leaving a task in a half-switched state which we
will make use of in t

nsproxy: add struct nsset

Add a simple struct nsset. It holds all necessary pieces to switch to a new
set of namespaces without leaving a task in a half-switched state which we
will make use of in the next patch. This patch switches the existing setns
logic over without causing a change in setns() behavior. This brings
setns() closer to how unshare() works(). The prepare_ns() function is
responsible to prepare all necessary information. This has two reasons.
First it minimizes dependencies between individual namespaces, i.e. all
install handler can expect that all fields are properly initialized
independent in what order they are called in. Second, this makes the code
easier to maintain and easier to follow if it needs to be changed.

The prepare_ns() helper will only be switched over to use a flags argument
in the next patch. Here it will still use nstype as a simple integer
argument which was argued would be clearer. I'm not particularly
opinionated about this if it really helps or not. The struct nsset itself
already contains the flags field since its name already indicates that it
can contain information required by different namespaces. None of this
should have functional consequences.

Signed-off-by: Christian Brauner <[email protected]>
Reviewed-by: Serge Hallyn <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Serge Hallyn <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Michael Kerrisk <[email protected]>
Cc: Aleksa Sarai <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

ipc: Convert mqueue fs to fs_context

Convert the mqueue filesystem to use the filesystem context stuff.

Notes:

(1) The relevant ipc namespace is selected in when the context is
initialised (

ipc: Convert mqueue fs to fs_context

Convert the mqueue filesystem to use the filesystem context stuff.

Notes:

(1) The relevant ipc namespace is selected in when the context is
initialised (and it defaults to the current task's ipc namespace).
The caller can override this before calling vfs_get_tree().

(2) Rather than simply calling kern_mount_data(), mq_init_ns() and
mq_internal_mount() create a context, adjust it and then do the rest
of the mount procedure.

(3) The lazy mqueue mounting on creation of a new namespace is retained
from a previous patch, but the avoidance of sget() if no superblock
yet exists is reverted and the superblock is again keyed on the
namespace pointer.

Yes, there was a performance gain in not searching the superblock
hash, but it's only paid once per ipc namespace - and only if someone
uses mqueue within that namespace, so I'm not sure it's worth it,
especially as calling sget() allows avoidance of recursion.

Signed-off-by: David Howells <[email protected]>
Signed-off-by: Al Viro <[email protected]>

show more ...

ipc: simplify ipc initialization

Now that we know that rhashtable_init() will not fail, we can get rid of a
lot of the unnecessary cleanup paths when the call errored out.

[[email protected]

ipc: simplify ipc initialization

Now that we know that rhashtable_init() will not fail, we can get rid of a
lot of the unnecessary cleanup paths when the call errored out.

[[email protected]: variable name added to util.h to resolve checkpatch warning]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Davidlohr Bueso <[email protected]>
Signed-off-by: Manfred Spraul <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Michael Kerrisk <[email protected]>
Cc: Michal Hocko <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

ipc: optimize semget/shmget/msgget for lots of keys

ipc_findkey() used to scan all objects to look for the wanted key. This
is slow when using a high number of keys. This change adds an rhashtable

ipc: optimize semget/shmget/msgget for lots of keys

ipc_findkey() used to scan all objects to look for the wanted key. This
is slow when using a high number of keys. This change adds an rhashtable
of kern_ipc_perm objects in ipc_ids, so that one lookup cease to be O(n).

This change gives a 865% improvement of benchmark reaim.jobs_per_min on a
56 threads Intel(R) Xeon(R) CPU E5-2695 v3 @ 2.30GHz with 256G memory [1]

Other (more micro) benchmark results, by the author: On an i5 laptop, the
following loop executed right after a reboot took, without and with this
change:

for (int i = 0, k=0x424242; i < KEYS; ++i)
semget(k++, 1, IPC_CREAT | 0600);

total total max single max single
KEYS without with call without call with

1 3.5 4.9 µs 3.5 4.9
10 7.6 8.6 µs 3.7 4.7
32 16.2 15.9 µs 4.3 5.3
100 72.9 41.8 µs 3.7 4.7
1000 5,630.0 502.0 µs * *
10000 1,340,000.0 7,240.0 µs * *
31900 17,600,000.0 22,200.0 µs * *

*: unreliable measure: high variance

The duration for a lookup-only usage was obtained by the same loop once
the keys are present:

total total max single max single
KEYS without with call without call with

1 2.1 2.5 µs 2.1 2.5
10 4.5 4.8 µs 2.2 2.3
32 13.0 10.8 µs 2.3 2.8
100 82.9 25.1 µs * 2.3
1000 5,780.0 217.0 µs * *
10000 1,470,000.0 2,520.0 µs * *
31900 17,400,000.0 7,810.0 µs * *

Finally, executing each semget() in a new process gave, when still
summing only the durations of these syscalls:

creation:
total total
KEYS without with

1 3.7 5.0 µs
10 32.9 36.7 µs
32 125.0 109.0 µs
100 523.0 353.0 µs
1000 20,300.0 3,280.0 µs
10000 2,470,000.0 46,700.0 µs
31900 27,800,000.0 219,000.0 µs

lookup-only:
total total
KEYS without with

1 2.5 2.7 µs
10 25.4 24.4 µs
32 106.0 72.6 µs
100 591.0 352.0 µs
1000 22,400.0 2,250.0 µs
10000 2,510,000.0 25,700.0 µs
31900 28,200,000.0 115,000.0 µs

[1] http://lkml.kernel.org/r/20170814060507.GE23258@yexl-desktop

Link: http://lkml.kernel.org/r/20170815194954.ck32ta2z35yuzpwp@debix
Signed-off-by: Guillaume Knispel <[email protected]>
Reviewed-by: Marc Pardo <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Manfred Spraul <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: "Peter Zijlstra (Intel)" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: Serge Hallyn <[email protected]>
Cc: Andrey Vagin <[email protected]>
Cc: Guillaume Knispel <[email protected]>
Cc: Marc Pardo <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

ipc: convert ipc_namespace.count from atomic_t to refcount_t

refcount_t type and corresponding API should be used instead of atomic_t
when the variable is used as a reference counter. This allows t

ipc: convert ipc_namespace.count from atomic_t to refcount_t

refcount_t type and corresponding API should be used instead of atomic_t
when the variable is used as a reference counter. This allows to avoid
accidental refcounter overflows that might lead to use-after-free
situations.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Elena Reshetova <[email protected]>
Signed-off-by: Hans Liljestrand <[email protected]>
Signed-off-by: Kees Cook <[email protected]>
Signed-off-by: David Windsor <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: Serge Hallyn <[email protected]>
Cc: <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Manfred Spraul <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h>

But first update the code that uses these facilities with the
new header.

Acked-by: Linus Torvalds <torvalds@lin

sched/headers: Prepare to move the task_lock()/unlock() APIs to <linux/sched/task.h>

But first update the code that uses these facilities with the
new header.

Acked-by: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>

Add #include <linux/cred.h> dependencies to all .c files rely on sched.h
doing that for them.

Note that even if the co

sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>

Add #include <linux/cred.h> dependencies to all .c files rely on sched.h
doing that for them.

Note that even if the count where we need to add extra headers seems high,
it's still a net win, because <linux/sched.h> is included in over
2,200 files ...

Acked-by: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

show more ...

kernel: add a helper to get an owning user namespace for a namespace

Return -EPERM if an owning user namespace is outside of a process
current user namespace.

v2: In a first version ns_get_owner re

kernel: add a helper to get an owning user namespace for a namespace

Return -EPERM if an owning user namespace is outside of a process
current user namespace.

v2: In a first version ns_get_owner returned ENOENT for init_user_ns.
This special cases was removed from this version. There is nothing
outside of init_user_ns, so we can return EPERM.
v3: rename ns->get_owner() to ns->owner(). get_* usually means that it
grabs a reference.

Acked-by: Serge Hallyn <[email protected]>
Signed-off-by: Andrei Vagin <[email protected]>
Signed-off-by: Eric W. Biederman <[email protected]>

show more ...

userns: When the per user per user namespace limit is reached return ENOSPC

The current error codes returned when a the per user per user
namespace limit are hit (EINVAL, EUSERS, and ENFILE) are wro

userns: When the per user per user namespace limit is reached return ENOSPC

The current error codes returned when a the per user per user
namespace limit are hit (EINVAL, EUSERS, and ENFILE) are wrong. I
asked for advice on linux-api and it we made clear that those were
the wrong error code, but a correct effor code was not suggested.

The best general error code I have found for hitting a resource limit
is ENOSPC. It is not perfect but as it is unambiguous it will serve
until someone comes up with a better error code.

Signed-off-by: "Eric W. Biederman" <[email protected]>

show more ...

ipcns: Add a limit on the number of ipc namespaces

Acked-by: Kees Cook <[email protected]>
Signed-off-by: "Eric W. Biederman" <[email protected]>

ipc: delete "nr_ipc_ns"

Write-only variable.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Alexey Dobriyan <[email protected]>
Signed-off-by: Andrew Morton <

ipc: delete "nr_ipc_ns"

Write-only variable.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Alexey Dobriyan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

ipc: Initialize ipc_namespace->user_ns early.

Allow the ipc namespace initialization code to depend on ns->user_ns
being set during initialization.

In particular this allows mq_init_ns to use ns->u

ipc: Initialize ipc_namespace->user_ns early.

Allow the ipc namespace initialization code to depend on ns->user_ns
being set during initialization.

In particular this allows mq_init_ns to use ns->user_ns for permission
checks and initializating s_user_ns while the the mq filesystem is
being mounted.

Acked-by: Seth Forshee <[email protected]>
Suggested-by: Seth Forshee <[email protected]>
Signed-off-by: "Eric W. Biederman" <[email protected]>

show more ...

ipc/msg: increase MSGMNI, remove scaling

SysV can be abused to allocate locked kernel memory. For most systems, a
small limit doesn't make sense, see the discussion with regards to SHMMAX.

Therefo

ipc/msg: increase MSGMNI, remove scaling

SysV can be abused to allocate locked kernel memory. For most systems, a
small limit doesn't make sense, see the discussion with regards to SHMMAX.

Therefore: increase MSGMNI to the maximum supported.

And: If we ignore the risk of locking too much memory, then an automatic
scaling of MSGMNI doesn't make sense. Therefore the logic can be removed.

The code preserves auto_msgmni to avoid breaking any user space applications
that expect that the value exists.

Notes:
1) If an administrator must limit the memory allocations, then he can set
MSGMNI as necessary.

Or he can disable sysv entirely (as e.g. done by Android).

2) MSGMAX and MSGMNB are intentionally not increased, as these values are used
to control latency vs. throughput:
If MSGMNB is large, then msgsnd() just returns and more messages can be queued
before a task switch to a task that calls msgrcv() is forced.

[[email protected]: coding-style fixes]
Signed-off-by: Manfred Spraul <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Rafael Aquini <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

copy address of proc_ns_ops into ns_common

Signed-off-by: Al Viro <[email protected]>