diff options
author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /kernel/time/namespace.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to 'kernel/time/namespace.c')
-rw-r--r-- | kernel/time/namespace.c | 485 |
1 files changed, 485 insertions, 0 deletions
diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c new file mode 100644 index 000000000..0775b9ec9 --- /dev/null +++ b/kernel/time/namespace.c @@ -0,0 +1,485 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Author: Andrei Vagin <avagin@openvz.org> + * Author: Dmitry Safonov <dima@arista.com> + */ + +#include <linux/time_namespace.h> +#include <linux/user_namespace.h> +#include <linux/sched/signal.h> +#include <linux/sched/task.h> +#include <linux/clocksource.h> +#include <linux/seq_file.h> +#include <linux/proc_ns.h> +#include <linux/export.h> +#include <linux/time.h> +#include <linux/slab.h> +#include <linux/cred.h> +#include <linux/err.h> +#include <linux/mm.h> + +#include <vdso/datapage.h> + +ktime_t do_timens_ktime_to_host(clockid_t clockid, ktime_t tim, + struct timens_offsets *ns_offsets) +{ + ktime_t offset; + + switch (clockid) { + case CLOCK_MONOTONIC: + offset = timespec64_to_ktime(ns_offsets->monotonic); + break; + case CLOCK_BOOTTIME: + case CLOCK_BOOTTIME_ALARM: + offset = timespec64_to_ktime(ns_offsets->boottime); + break; + default: + return tim; + } + + /* + * Check that @tim value is in [offset, KTIME_MAX + offset] + * and subtract offset. + */ + if (tim < offset) { + /* + * User can specify @tim *absolute* value - if it's lesser than + * the time namespace's offset - it's already expired. + */ + tim = 0; + } else { + tim = ktime_sub(tim, offset); + if (unlikely(tim > KTIME_MAX)) + tim = KTIME_MAX; + } + + return tim; +} + +static struct ucounts *inc_time_namespaces(struct user_namespace *ns) +{ + return inc_ucount(ns, current_euid(), UCOUNT_TIME_NAMESPACES); +} + +static void dec_time_namespaces(struct ucounts *ucounts) +{ + dec_ucount(ucounts, UCOUNT_TIME_NAMESPACES); +} + +/** + * clone_time_ns - Clone a time namespace + * @user_ns: User namespace which owns a new namespace. + * @old_ns: Namespace to clone + * + * Clone @old_ns and set the clone refcount to 1 + * + * Return: The new namespace or ERR_PTR. + */ +static struct time_namespace *clone_time_ns(struct user_namespace *user_ns, + struct time_namespace *old_ns) +{ + struct time_namespace *ns; + struct ucounts *ucounts; + int err; + + err = -ENOSPC; + ucounts = inc_time_namespaces(user_ns); + if (!ucounts) + goto fail; + + err = -ENOMEM; + ns = kmalloc(sizeof(*ns), GFP_KERNEL_ACCOUNT); + if (!ns) + goto fail_dec; + + refcount_set(&ns->ns.count, 1); + + ns->vvar_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO); + if (!ns->vvar_page) + goto fail_free; + + err = ns_alloc_inum(&ns->ns); + if (err) + goto fail_free_page; + + ns->ucounts = ucounts; + ns->ns.ops = &timens_operations; + ns->user_ns = get_user_ns(user_ns); + ns->offsets = old_ns->offsets; + ns->frozen_offsets = false; + return ns; + +fail_free_page: + __free_page(ns->vvar_page); +fail_free: + kfree(ns); +fail_dec: + dec_time_namespaces(ucounts); +fail: + return ERR_PTR(err); +} + +/** + * copy_time_ns - Create timens_for_children from @old_ns + * @flags: Cloning flags + * @user_ns: User namespace which owns a new namespace. + * @old_ns: Namespace to clone + * + * If CLONE_NEWTIME specified in @flags, creates a new timens_for_children; + * adds a refcounter to @old_ns otherwise. + * + * Return: timens_for_children namespace or ERR_PTR. + */ +struct time_namespace *copy_time_ns(unsigned long flags, + struct user_namespace *user_ns, struct time_namespace *old_ns) +{ + if (!(flags & CLONE_NEWTIME)) + return get_time_ns(old_ns); + + return clone_time_ns(user_ns, old_ns); +} + +static struct timens_offset offset_from_ts(struct timespec64 off) +{ + struct timens_offset ret; + + ret.sec = off.tv_sec; + ret.nsec = off.tv_nsec; + + return ret; +} + +/* + * A time namespace VVAR page has the same layout as the VVAR page which + * contains the system wide VDSO data. + * + * For a normal task the VVAR pages are installed in the normal ordering: + * VVAR + * PVCLOCK + * HVCLOCK + * TIMENS <- Not really required + * + * Now for a timens task the pages are installed in the following order: + * TIMENS + * PVCLOCK + * HVCLOCK + * VVAR + * + * The check for vdso_data->clock_mode is in the unlikely path of + * the seq begin magic. So for the non-timens case most of the time + * 'seq' is even, so the branch is not taken. + * + * If 'seq' is odd, i.e. a concurrent update is in progress, the extra check + * for vdso_data->clock_mode is a non-issue. The task is spin waiting for the + * update to finish and for 'seq' to become even anyway. + * + * Timens page has vdso_data->clock_mode set to VDSO_CLOCKMODE_TIMENS which + * enforces the time namespace handling path. + */ +static void timens_setup_vdso_data(struct vdso_data *vdata, + struct time_namespace *ns) +{ + struct timens_offset *offset = vdata->offset; + struct timens_offset monotonic = offset_from_ts(ns->offsets.monotonic); + struct timens_offset boottime = offset_from_ts(ns->offsets.boottime); + + vdata->seq = 1; + vdata->clock_mode = VDSO_CLOCKMODE_TIMENS; + offset[CLOCK_MONOTONIC] = monotonic; + offset[CLOCK_MONOTONIC_RAW] = monotonic; + offset[CLOCK_MONOTONIC_COARSE] = monotonic; + offset[CLOCK_BOOTTIME] = boottime; + offset[CLOCK_BOOTTIME_ALARM] = boottime; +} + +struct page *find_timens_vvar_page(struct vm_area_struct *vma) +{ + if (likely(vma->vm_mm == current->mm)) + return current->nsproxy->time_ns->vvar_page; + + /* + * VM_PFNMAP | VM_IO protect .fault() handler from being called + * through interfaces like /proc/$pid/mem or + * process_vm_{readv,writev}() as long as there's no .access() + * in special_mapping_vmops(). + * For more details check_vma_flags() and __access_remote_vm() + */ + + WARN(1, "vvar_page accessed remotely"); + + return NULL; +} + +/* + * Protects possibly multiple offsets writers racing each other + * and tasks entering the namespace. + */ +static DEFINE_MUTEX(offset_lock); + +static void timens_set_vvar_page(struct task_struct *task, + struct time_namespace *ns) +{ + struct vdso_data *vdata; + unsigned int i; + + if (ns == &init_time_ns) + return; + + /* Fast-path, taken by every task in namespace except the first. */ + if (likely(ns->frozen_offsets)) + return; + + mutex_lock(&offset_lock); + /* Nothing to-do: vvar_page has been already initialized. */ + if (ns->frozen_offsets) + goto out; + + ns->frozen_offsets = true; + vdata = arch_get_vdso_data(page_address(ns->vvar_page)); + + for (i = 0; i < CS_BASES; i++) + timens_setup_vdso_data(&vdata[i], ns); + +out: + mutex_unlock(&offset_lock); +} + +void free_time_ns(struct time_namespace *ns) +{ + dec_time_namespaces(ns->ucounts); + put_user_ns(ns->user_ns); + ns_free_inum(&ns->ns); + __free_page(ns->vvar_page); + kfree(ns); +} + +static struct time_namespace *to_time_ns(struct ns_common *ns) +{ + return container_of(ns, struct time_namespace, ns); +} + +static struct ns_common *timens_get(struct task_struct *task) +{ + struct time_namespace *ns = NULL; + struct nsproxy *nsproxy; + + task_lock(task); + nsproxy = task->nsproxy; + if (nsproxy) { + ns = nsproxy->time_ns; + get_time_ns(ns); + } + task_unlock(task); + + return ns ? &ns->ns : NULL; +} + +static struct ns_common *timens_for_children_get(struct task_struct *task) +{ + struct time_namespace *ns = NULL; + struct nsproxy *nsproxy; + + task_lock(task); + nsproxy = task->nsproxy; + if (nsproxy) { + ns = nsproxy->time_ns_for_children; + get_time_ns(ns); + } + task_unlock(task); + + return ns ? &ns->ns : NULL; +} + +static void timens_put(struct ns_common *ns) +{ + put_time_ns(to_time_ns(ns)); +} + +void timens_commit(struct task_struct *tsk, struct time_namespace *ns) +{ + timens_set_vvar_page(tsk, ns); + vdso_join_timens(tsk, ns); +} + +static int timens_install(struct nsset *nsset, struct ns_common *new) +{ + struct nsproxy *nsproxy = nsset->nsproxy; + struct time_namespace *ns = to_time_ns(new); + + if (!current_is_single_threaded()) + return -EUSERS; + + if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN) || + !ns_capable(nsset->cred->user_ns, CAP_SYS_ADMIN)) + return -EPERM; + + get_time_ns(ns); + put_time_ns(nsproxy->time_ns); + nsproxy->time_ns = ns; + + get_time_ns(ns); + put_time_ns(nsproxy->time_ns_for_children); + nsproxy->time_ns_for_children = ns; + return 0; +} + +void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk) +{ + struct ns_common *nsc = &nsproxy->time_ns_for_children->ns; + struct time_namespace *ns = to_time_ns(nsc); + + /* create_new_namespaces() already incremented the ref counter */ + if (nsproxy->time_ns == nsproxy->time_ns_for_children) + return; + + get_time_ns(ns); + put_time_ns(nsproxy->time_ns); + nsproxy->time_ns = ns; + + timens_commit(tsk, ns); +} + +static struct user_namespace *timens_owner(struct ns_common *ns) +{ + return to_time_ns(ns)->user_ns; +} + +static void show_offset(struct seq_file *m, int clockid, struct timespec64 *ts) +{ + char *clock; + + switch (clockid) { + case CLOCK_BOOTTIME: + clock = "boottime"; + break; + case CLOCK_MONOTONIC: + clock = "monotonic"; + break; + default: + clock = "unknown"; + break; + } + seq_printf(m, "%-10s %10lld %9ld\n", clock, ts->tv_sec, ts->tv_nsec); +} + +void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m) +{ + struct ns_common *ns; + struct time_namespace *time_ns; + + ns = timens_for_children_get(p); + if (!ns) + return; + time_ns = to_time_ns(ns); + + show_offset(m, CLOCK_MONOTONIC, &time_ns->offsets.monotonic); + show_offset(m, CLOCK_BOOTTIME, &time_ns->offsets.boottime); + put_time_ns(time_ns); +} + +int proc_timens_set_offset(struct file *file, struct task_struct *p, + struct proc_timens_offset *offsets, int noffsets) +{ + struct ns_common *ns; + struct time_namespace *time_ns; + struct timespec64 tp; + int i, err; + + ns = timens_for_children_get(p); + if (!ns) + return -ESRCH; + time_ns = to_time_ns(ns); + + if (!file_ns_capable(file, time_ns->user_ns, CAP_SYS_TIME)) { + put_time_ns(time_ns); + return -EPERM; + } + + for (i = 0; i < noffsets; i++) { + struct proc_timens_offset *off = &offsets[i]; + + switch (off->clockid) { + case CLOCK_MONOTONIC: + ktime_get_ts64(&tp); + break; + case CLOCK_BOOTTIME: + ktime_get_boottime_ts64(&tp); + break; + default: + err = -EINVAL; + goto out; + } + + err = -ERANGE; + + if (off->val.tv_sec > KTIME_SEC_MAX || + off->val.tv_sec < -KTIME_SEC_MAX) + goto out; + + tp = timespec64_add(tp, off->val); + /* + * KTIME_SEC_MAX is divided by 2 to be sure that KTIME_MAX is + * still unreachable. + */ + if (tp.tv_sec < 0 || tp.tv_sec > KTIME_SEC_MAX / 2) + goto out; + } + + mutex_lock(&offset_lock); + if (time_ns->frozen_offsets) { + err = -EACCES; + goto out_unlock; + } + + err = 0; + /* Don't report errors after this line */ + for (i = 0; i < noffsets; i++) { + struct proc_timens_offset *off = &offsets[i]; + struct timespec64 *offset = NULL; + + switch (off->clockid) { + case CLOCK_MONOTONIC: + offset = &time_ns->offsets.monotonic; + break; + case CLOCK_BOOTTIME: + offset = &time_ns->offsets.boottime; + break; + } + + *offset = off->val; + } + +out_unlock: + mutex_unlock(&offset_lock); +out: + put_time_ns(time_ns); + + return err; +} + +const struct proc_ns_operations timens_operations = { + .name = "time", + .type = CLONE_NEWTIME, + .get = timens_get, + .put = timens_put, + .install = timens_install, + .owner = timens_owner, +}; + +const struct proc_ns_operations timens_for_children_operations = { + .name = "time_for_children", + .real_ns_name = "time", + .type = CLONE_NEWTIME, + .get = timens_for_children_get, + .put = timens_put, + .install = timens_install, + .owner = timens_owner, +}; + +struct time_namespace init_time_ns = { + .ns.count = REFCOUNT_INIT(3), + .user_ns = &init_user_ns, + .ns.inum = PROC_TIME_INIT_INO, + .ns.ops = &timens_operations, + .frozen_offsets = true, +}; |