aboutsummaryrefslogtreecommitdiff
path: root/fs/nsfs.c
diff options
context:
space:
mode:
authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /fs/nsfs.c
downloadlinux-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 'fs/nsfs.c')
-rw-r--r--fs/nsfs.c306
1 files changed, 306 insertions, 0 deletions
diff --git a/fs/nsfs.c b/fs/nsfs.c
new file mode 100644
index 000000000..3506f6074
--- /dev/null
+++ b/fs/nsfs.c
@@ -0,0 +1,306 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/mount.h>
+#include <linux/pseudo_fs.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/proc_ns.h>
+#include <linux/magic.h>
+#include <linux/ktime.h>
+#include <linux/seq_file.h>
+#include <linux/user_namespace.h>
+#include <linux/nsfs.h>
+#include <linux/uaccess.h>
+
+#include "internal.h"
+
+static struct vfsmount *nsfs_mnt;
+
+static long ns_ioctl(struct file *filp, unsigned int ioctl,
+ unsigned long arg);
+static const struct file_operations ns_file_operations = {
+ .llseek = no_llseek,
+ .unlocked_ioctl = ns_ioctl,
+};
+
+static char *ns_dname(struct dentry *dentry, char *buffer, int buflen)
+{
+ struct inode *inode = d_inode(dentry);
+ const struct proc_ns_operations *ns_ops = dentry->d_fsdata;
+
+ return dynamic_dname(buffer, buflen, "%s:[%lu]",
+ ns_ops->name, inode->i_ino);
+}
+
+static void ns_prune_dentry(struct dentry *dentry)
+{
+ struct inode *inode = d_inode(dentry);
+ if (inode) {
+ struct ns_common *ns = inode->i_private;
+ atomic_long_set(&ns->stashed, 0);
+ }
+}
+
+const struct dentry_operations ns_dentry_operations =
+{
+ .d_prune = ns_prune_dentry,
+ .d_delete = always_delete_dentry,
+ .d_dname = ns_dname,
+};
+
+static void nsfs_evict(struct inode *inode)
+{
+ struct ns_common *ns = inode->i_private;
+ clear_inode(inode);
+ ns->ops->put(ns);
+}
+
+static int __ns_get_path(struct path *path, struct ns_common *ns)
+{
+ struct vfsmount *mnt = nsfs_mnt;
+ struct dentry *dentry;
+ struct inode *inode;
+ unsigned long d;
+
+ rcu_read_lock();
+ d = atomic_long_read(&ns->stashed);
+ if (!d)
+ goto slow;
+ dentry = (struct dentry *)d;
+ if (!lockref_get_not_dead(&dentry->d_lockref))
+ goto slow;
+ rcu_read_unlock();
+ ns->ops->put(ns);
+got_it:
+ path->mnt = mntget(mnt);
+ path->dentry = dentry;
+ return 0;
+slow:
+ rcu_read_unlock();
+ inode = new_inode_pseudo(mnt->mnt_sb);
+ if (!inode) {
+ ns->ops->put(ns);
+ return -ENOMEM;
+ }
+ inode->i_ino = ns->inum;
+ inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
+ inode->i_flags |= S_IMMUTABLE;
+ inode->i_mode = S_IFREG | S_IRUGO;
+ inode->i_fop = &ns_file_operations;
+ inode->i_private = ns;
+
+ dentry = d_alloc_anon(mnt->mnt_sb);
+ if (!dentry) {
+ iput(inode);
+ return -ENOMEM;
+ }
+ d_instantiate(dentry, inode);
+ dentry->d_fsdata = (void *)ns->ops;
+ d = atomic_long_cmpxchg(&ns->stashed, 0, (unsigned long)dentry);
+ if (d) {
+ d_delete(dentry); /* make sure ->d_prune() does nothing */
+ dput(dentry);
+ cpu_relax();
+ return -EAGAIN;
+ }
+ goto got_it;
+}
+
+int ns_get_path_cb(struct path *path, ns_get_path_helper_t *ns_get_cb,
+ void *private_data)
+{
+ int ret;
+
+ do {
+ struct ns_common *ns = ns_get_cb(private_data);
+ if (!ns)
+ return -ENOENT;
+ ret = __ns_get_path(path, ns);
+ } while (ret == -EAGAIN);
+
+ return ret;
+}
+
+struct ns_get_path_task_args {
+ const struct proc_ns_operations *ns_ops;
+ struct task_struct *task;
+};
+
+static struct ns_common *ns_get_path_task(void *private_data)
+{
+ struct ns_get_path_task_args *args = private_data;
+
+ return args->ns_ops->get(args->task);
+}
+
+int ns_get_path(struct path *path, struct task_struct *task,
+ const struct proc_ns_operations *ns_ops)
+{
+ struct ns_get_path_task_args args = {
+ .ns_ops = ns_ops,
+ .task = task,
+ };
+
+ return ns_get_path_cb(path, ns_get_path_task, &args);
+}
+
+int open_related_ns(struct ns_common *ns,
+ struct ns_common *(*get_ns)(struct ns_common *ns))
+{
+ struct path path = {};
+ struct file *f;
+ int err;
+ int fd;
+
+ fd = get_unused_fd_flags(O_CLOEXEC);
+ if (fd < 0)
+ return fd;
+
+ do {
+ struct ns_common *relative;
+
+ relative = get_ns(ns);
+ if (IS_ERR(relative)) {
+ put_unused_fd(fd);
+ return PTR_ERR(relative);
+ }
+
+ err = __ns_get_path(&path, relative);
+ } while (err == -EAGAIN);
+
+ if (err) {
+ put_unused_fd(fd);
+ return err;
+ }
+
+ f = dentry_open(&path, O_RDONLY, current_cred());
+ path_put(&path);
+ if (IS_ERR(f)) {
+ put_unused_fd(fd);
+ fd = PTR_ERR(f);
+ } else
+ fd_install(fd, f);
+
+ return fd;
+}
+EXPORT_SYMBOL_GPL(open_related_ns);
+
+static long ns_ioctl(struct file *filp, unsigned int ioctl,
+ unsigned long arg)
+{
+ struct user_namespace *user_ns;
+ struct ns_common *ns = get_proc_ns(file_inode(filp));
+ uid_t __user *argp;
+ uid_t uid;
+
+ switch (ioctl) {
+ case NS_GET_USERNS:
+ return open_related_ns(ns, ns_get_owner);
+ case NS_GET_PARENT:
+ if (!ns->ops->get_parent)
+ return -EINVAL;
+ return open_related_ns(ns, ns->ops->get_parent);
+ case NS_GET_NSTYPE:
+ return ns->ops->type;
+ case NS_GET_OWNER_UID:
+ if (ns->ops->type != CLONE_NEWUSER)
+ return -EINVAL;
+ user_ns = container_of(ns, struct user_namespace, ns);
+ argp = (uid_t __user *) arg;
+ uid = from_kuid_munged(current_user_ns(), user_ns->owner);
+ return put_user(uid, argp);
+ default:
+ return -ENOTTY;
+ }
+}
+
+int ns_get_name(char *buf, size_t size, struct task_struct *task,
+ const struct proc_ns_operations *ns_ops)
+{
+ struct ns_common *ns;
+ int res = -ENOENT;
+ const char *name;
+ ns = ns_ops->get(task);
+ if (ns) {
+ name = ns_ops->real_ns_name ? : ns_ops->name;
+ res = snprintf(buf, size, "%s:[%u]", name, ns->inum);
+ ns_ops->put(ns);
+ }
+ return res;
+}
+
+bool proc_ns_file(const struct file *file)
+{
+ return file->f_op == &ns_file_operations;
+}
+
+struct file *proc_ns_fget(int fd)
+{
+ struct file *file;
+
+ file = fget(fd);
+ if (!file)
+ return ERR_PTR(-EBADF);
+
+ if (file->f_op != &ns_file_operations)
+ goto out_invalid;
+
+ return file;
+
+out_invalid:
+ fput(file);
+ return ERR_PTR(-EINVAL);
+}
+
+/**
+ * ns_match() - Returns true if current namespace matches dev/ino provided.
+ * @ns_common: current ns
+ * @dev: dev_t from nsfs that will be matched against current nsfs
+ * @ino: ino_t from nsfs that will be matched against current nsfs
+ *
+ * Return: true if dev and ino matches the current nsfs.
+ */
+bool ns_match(const struct ns_common *ns, dev_t dev, ino_t ino)
+{
+ return (ns->inum == ino) && (nsfs_mnt->mnt_sb->s_dev == dev);
+}
+
+
+static int nsfs_show_path(struct seq_file *seq, struct dentry *dentry)
+{
+ struct inode *inode = d_inode(dentry);
+ const struct proc_ns_operations *ns_ops = dentry->d_fsdata;
+
+ seq_printf(seq, "%s:[%lu]", ns_ops->name, inode->i_ino);
+ return 0;
+}
+
+static const struct super_operations nsfs_ops = {
+ .statfs = simple_statfs,
+ .evict_inode = nsfs_evict,
+ .show_path = nsfs_show_path,
+};
+
+static int nsfs_init_fs_context(struct fs_context *fc)
+{
+ struct pseudo_fs_context *ctx = init_pseudo(fc, NSFS_MAGIC);
+ if (!ctx)
+ return -ENOMEM;
+ ctx->ops = &nsfs_ops;
+ ctx->dops = &ns_dentry_operations;
+ return 0;
+}
+
+static struct file_system_type nsfs = {
+ .name = "nsfs",
+ .init_fs_context = nsfs_init_fs_context,
+ .kill_sb = kill_anon_super,
+};
+
+void __init nsfs_init(void)
+{
+ nsfs_mnt = kern_mount(&nsfs);
+ if (IS_ERR(nsfs_mnt))
+ panic("can't set nsfs up\n");
+ nsfs_mnt->mnt_sb->s_flags &= ~SB_NOUSER;
+}