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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 /arch/x86/um/tls_32.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 'arch/x86/um/tls_32.c')
-rw-r--r--arch/x86/um/tls_32.c390
1 files changed, 390 insertions, 0 deletions
diff --git a/arch/x86/um/tls_32.c b/arch/x86/um/tls_32.c
new file mode 100644
index 000000000..66162eafd
--- /dev/null
+++ b/arch/x86/um/tls_32.c
@@ -0,0 +1,390 @@
+/*
+ * Copyright (C) 2005 Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
+ * Licensed under the GPL
+ */
+
+#include <linux/percpu.h>
+#include <linux/sched.h>
+#include <linux/syscalls.h>
+#include <linux/uaccess.h>
+#include <asm/ptrace-abi.h>
+#include <os.h>
+#include <skas.h>
+#include <sysdep/tls.h>
+
+/*
+ * If needed we can detect when it's uninitialized.
+ *
+ * These are initialized in an initcall and unchanged thereafter.
+ */
+static int host_supports_tls = -1;
+int host_gdt_entry_tls_min;
+
+int do_set_thread_area(struct user_desc *info)
+{
+ int ret;
+ u32 cpu;
+
+ cpu = get_cpu();
+ ret = os_set_thread_area(info, userspace_pid[cpu]);
+ put_cpu();
+
+ if (ret)
+ printk(KERN_ERR "PTRACE_SET_THREAD_AREA failed, err = %d, "
+ "index = %d\n", ret, info->entry_number);
+
+ return ret;
+}
+
+int do_get_thread_area(struct user_desc *info)
+{
+ int ret;
+ u32 cpu;
+
+ cpu = get_cpu();
+ ret = os_get_thread_area(info, userspace_pid[cpu]);
+ put_cpu();
+
+ if (ret)
+ printk(KERN_ERR "PTRACE_GET_THREAD_AREA failed, err = %d, "
+ "index = %d\n", ret, info->entry_number);
+
+ return ret;
+}
+
+/*
+ * sys_get_thread_area: get a yet unused TLS descriptor index.
+ * XXX: Consider leaving one free slot for glibc usage at first place. This must
+ * be done here (and by changing GDT_ENTRY_TLS_* macros) and nowhere else.
+ *
+ * Also, this must be tested when compiling in SKAS mode with dynamic linking
+ * and running against NPTL.
+ */
+static int get_free_idx(struct task_struct* task)
+{
+ struct thread_struct *t = &task->thread;
+ int idx;
+
+ for (idx = 0; idx < GDT_ENTRY_TLS_ENTRIES; idx++)
+ if (!t->arch.tls_array[idx].present)
+ return idx + GDT_ENTRY_TLS_MIN;
+ return -ESRCH;
+}
+
+static inline void clear_user_desc(struct user_desc* info)
+{
+ /* Postcondition: LDT_empty(info) returns true. */
+ memset(info, 0, sizeof(*info));
+
+ /*
+ * Check the LDT_empty or the i386 sys_get_thread_area code - we obtain
+ * indeed an empty user_desc.
+ */
+ info->read_exec_only = 1;
+ info->seg_not_present = 1;
+}
+
+#define O_FORCE 1
+
+static int load_TLS(int flags, struct task_struct *to)
+{
+ int ret = 0;
+ int idx;
+
+ for (idx = GDT_ENTRY_TLS_MIN; idx < GDT_ENTRY_TLS_MAX; idx++) {
+ struct uml_tls_struct* curr =
+ &to->thread.arch.tls_array[idx - GDT_ENTRY_TLS_MIN];
+
+ /*
+ * Actually, now if it wasn't flushed it gets cleared and
+ * flushed to the host, which will clear it.
+ */
+ if (!curr->present) {
+ if (!curr->flushed) {
+ clear_user_desc(&curr->tls);
+ curr->tls.entry_number = idx;
+ } else {
+ WARN_ON(!LDT_empty(&curr->tls));
+ continue;
+ }
+ }
+
+ if (!(flags & O_FORCE) && curr->flushed)
+ continue;
+
+ ret = do_set_thread_area(&curr->tls);
+ if (ret)
+ goto out;
+
+ curr->flushed = 1;
+ }
+out:
+ return ret;
+}
+
+/*
+ * Verify if we need to do a flush for the new process, i.e. if there are any
+ * present desc's, only if they haven't been flushed.
+ */
+static inline int needs_TLS_update(struct task_struct *task)
+{
+ int i;
+ int ret = 0;
+
+ for (i = GDT_ENTRY_TLS_MIN; i < GDT_ENTRY_TLS_MAX; i++) {
+ struct uml_tls_struct* curr =
+ &task->thread.arch.tls_array[i - GDT_ENTRY_TLS_MIN];
+
+ /*
+ * Can't test curr->present, we may need to clear a descriptor
+ * which had a value.
+ */
+ if (curr->flushed)
+ continue;
+ ret = 1;
+ break;
+ }
+ return ret;
+}
+
+/*
+ * On a newly forked process, the TLS descriptors haven't yet been flushed. So
+ * we mark them as such and the first switch_to will do the job.
+ */
+void clear_flushed_tls(struct task_struct *task)
+{
+ int i;
+
+ for (i = GDT_ENTRY_TLS_MIN; i < GDT_ENTRY_TLS_MAX; i++) {
+ struct uml_tls_struct* curr =
+ &task->thread.arch.tls_array[i - GDT_ENTRY_TLS_MIN];
+
+ /*
+ * Still correct to do this, if it wasn't present on the host it
+ * will remain as flushed as it was.
+ */
+ if (!curr->present)
+ continue;
+
+ curr->flushed = 0;
+ }
+}
+
+/*
+ * In SKAS0 mode, currently, multiple guest threads sharing the same ->mm have a
+ * common host process. So this is needed in SKAS0 too.
+ *
+ * However, if each thread had a different host process (and this was discussed
+ * for SMP support) this won't be needed.
+ *
+ * And this will not need be used when (and if) we'll add support to the host
+ * SKAS patch.
+ */
+
+int arch_switch_tls(struct task_struct *to)
+{
+ if (!host_supports_tls)
+ return 0;
+
+ /*
+ * We have no need whatsoever to switch TLS for kernel threads; beyond
+ * that, that would also result in us calling os_set_thread_area with
+ * userspace_pid[cpu] == 0, which gives an error.
+ */
+ if (likely(to->mm))
+ return load_TLS(O_FORCE, to);
+
+ return 0;
+}
+
+static int set_tls_entry(struct task_struct* task, struct user_desc *info,
+ int idx, int flushed)
+{
+ struct thread_struct *t = &task->thread;
+
+ if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
+ return -EINVAL;
+
+ t->arch.tls_array[idx - GDT_ENTRY_TLS_MIN].tls = *info;
+ t->arch.tls_array[idx - GDT_ENTRY_TLS_MIN].present = 1;
+ t->arch.tls_array[idx - GDT_ENTRY_TLS_MIN].flushed = flushed;
+
+ return 0;
+}
+
+int arch_set_tls(struct task_struct *new, unsigned long tls)
+{
+ struct user_desc info;
+ int idx, ret = -EFAULT;
+
+ if (copy_from_user(&info, (void __user *) tls, sizeof(info)))
+ goto out;
+
+ ret = -EINVAL;
+ if (LDT_empty(&info))
+ goto out;
+
+ idx = info.entry_number;
+
+ ret = set_tls_entry(new, &info, idx, 0);
+out:
+ return ret;
+}
+
+/* XXX: use do_get_thread_area to read the host value? I'm not at all sure! */
+static int get_tls_entry(struct task_struct *task, struct user_desc *info,
+ int idx)
+{
+ struct thread_struct *t = &task->thread;
+
+ if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
+ return -EINVAL;
+
+ if (!t->arch.tls_array[idx - GDT_ENTRY_TLS_MIN].present)
+ goto clear;
+
+ *info = t->arch.tls_array[idx - GDT_ENTRY_TLS_MIN].tls;
+
+out:
+ /*
+ * Temporary debugging check, to make sure that things have been
+ * flushed. This could be triggered if load_TLS() failed.
+ */
+ if (unlikely(task == current &&
+ !t->arch.tls_array[idx - GDT_ENTRY_TLS_MIN].flushed)) {
+ printk(KERN_ERR "get_tls_entry: task with pid %d got here "
+ "without flushed TLS.", current->pid);
+ }
+
+ return 0;
+clear:
+ /*
+ * When the TLS entry has not been set, the values read to user in the
+ * tls_array are 0 (because it's cleared at boot, see
+ * arch/i386/kernel/head.S:cpu_gdt_table). Emulate that.
+ */
+ clear_user_desc(info);
+ info->entry_number = idx;
+ goto out;
+}
+
+SYSCALL_DEFINE1(set_thread_area, struct user_desc __user *, user_desc)
+{
+ struct user_desc info;
+ int idx, ret;
+
+ if (!host_supports_tls)
+ return -ENOSYS;
+
+ if (copy_from_user(&info, user_desc, sizeof(info)))
+ return -EFAULT;
+
+ idx = info.entry_number;
+
+ if (idx == -1) {
+ idx = get_free_idx(current);
+ if (idx < 0)
+ return idx;
+ info.entry_number = idx;
+ /* Tell the user which slot we chose for him.*/
+ if (put_user(idx, &user_desc->entry_number))
+ return -EFAULT;
+ }
+
+ ret = do_set_thread_area(&info);
+ if (ret)
+ return ret;
+ return set_tls_entry(current, &info, idx, 1);
+}
+
+/*
+ * Perform set_thread_area on behalf of the traced child.
+ * Note: error handling is not done on the deferred load, and this differ from
+ * i386. However the only possible error are caused by bugs.
+ */
+int ptrace_set_thread_area(struct task_struct *child, int idx,
+ struct user_desc __user *user_desc)
+{
+ struct user_desc info;
+
+ if (!host_supports_tls)
+ return -EIO;
+
+ if (copy_from_user(&info, user_desc, sizeof(info)))
+ return -EFAULT;
+
+ return set_tls_entry(child, &info, idx, 0);
+}
+
+SYSCALL_DEFINE1(get_thread_area, struct user_desc __user *, user_desc)
+{
+ struct user_desc info;
+ int idx, ret;
+
+ if (!host_supports_tls)
+ return -ENOSYS;
+
+ if (get_user(idx, &user_desc->entry_number))
+ return -EFAULT;
+
+ ret = get_tls_entry(current, &info, idx);
+ if (ret < 0)
+ goto out;
+
+ if (copy_to_user(user_desc, &info, sizeof(info)))
+ ret = -EFAULT;
+
+out:
+ return ret;
+}
+
+/*
+ * Perform get_thread_area on behalf of the traced child.
+ */
+int ptrace_get_thread_area(struct task_struct *child, int idx,
+ struct user_desc __user *user_desc)
+{
+ struct user_desc info;
+ int ret;
+
+ if (!host_supports_tls)
+ return -EIO;
+
+ ret = get_tls_entry(child, &info, idx);
+ if (ret < 0)
+ goto out;
+
+ if (copy_to_user(user_desc, &info, sizeof(info)))
+ ret = -EFAULT;
+out:
+ return ret;
+}
+
+/*
+ * This code is really i386-only, but it detects and logs x86_64 GDT indexes
+ * if a 32-bit UML is running on a 64-bit host.
+ */
+static int __init __setup_host_supports_tls(void)
+{
+ check_host_supports_tls(&host_supports_tls, &host_gdt_entry_tls_min);
+ if (host_supports_tls) {
+ printk(KERN_INFO "Host TLS support detected\n");
+ printk(KERN_INFO "Detected host type: ");
+ switch (host_gdt_entry_tls_min) {
+ case GDT_ENTRY_TLS_MIN_I386:
+ printk(KERN_CONT "i386");
+ break;
+ case GDT_ENTRY_TLS_MIN_X86_64:
+ printk(KERN_CONT "x86_64");
+ break;
+ }
+ printk(KERN_CONT " (GDT indexes %d to %d)\n",
+ host_gdt_entry_tls_min,
+ host_gdt_entry_tls_min + GDT_ENTRY_TLS_ENTRIES);
+ } else
+ printk(KERN_ERR " Host TLS support NOT detected! "
+ "TLS support inside UML will not work\n");
+ return 0;
+}
+
+__initcall(__setup_host_supports_tls);