aboutsummaryrefslogtreecommitdiff
path: root/kernel/fail_function.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 /kernel/fail_function.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 'kernel/fail_function.c')
-rw-r--r--kernel/fail_function.c337
1 files changed, 337 insertions, 0 deletions
diff --git a/kernel/fail_function.c b/kernel/fail_function.c
new file mode 100644
index 000000000..a7ccd2930
--- /dev/null
+++ b/kernel/fail_function.c
@@ -0,0 +1,337 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * fail_function.c: Function-based error injection
+ */
+#include <linux/error-injection.h>
+#include <linux/debugfs.h>
+#include <linux/fault-inject.h>
+#include <linux/kallsyms.h>
+#include <linux/kprobes.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+static int fei_kprobe_handler(struct kprobe *kp, struct pt_regs *regs);
+
+static void fei_post_handler(struct kprobe *kp, struct pt_regs *regs,
+ unsigned long flags)
+{
+ /*
+ * A dummy post handler is required to prohibit optimizing, because
+ * jump optimization does not support execution path overriding.
+ */
+}
+
+struct fei_attr {
+ struct list_head list;
+ struct kprobe kp;
+ unsigned long retval;
+};
+static DEFINE_MUTEX(fei_lock);
+static LIST_HEAD(fei_attr_list);
+static DECLARE_FAULT_ATTR(fei_fault_attr);
+static struct dentry *fei_debugfs_dir;
+
+static unsigned long adjust_error_retval(unsigned long addr, unsigned long retv)
+{
+ switch (get_injectable_error_type(addr)) {
+ case EI_ETYPE_NULL:
+ return 0;
+ case EI_ETYPE_ERRNO:
+ if (retv < (unsigned long)-MAX_ERRNO)
+ return (unsigned long)-EINVAL;
+ break;
+ case EI_ETYPE_ERRNO_NULL:
+ if (retv != 0 && retv < (unsigned long)-MAX_ERRNO)
+ return (unsigned long)-EINVAL;
+ break;
+ case EI_ETYPE_TRUE:
+ return 1;
+ }
+
+ return retv;
+}
+
+static struct fei_attr *fei_attr_new(const char *sym, unsigned long addr)
+{
+ struct fei_attr *attr;
+
+ attr = kzalloc(sizeof(*attr), GFP_KERNEL);
+ if (attr) {
+ attr->kp.symbol_name = kstrdup(sym, GFP_KERNEL);
+ if (!attr->kp.symbol_name) {
+ kfree(attr);
+ return NULL;
+ }
+ attr->kp.pre_handler = fei_kprobe_handler;
+ attr->kp.post_handler = fei_post_handler;
+ attr->retval = adjust_error_retval(addr, 0);
+ INIT_LIST_HEAD(&attr->list);
+ }
+ return attr;
+}
+
+static void fei_attr_free(struct fei_attr *attr)
+{
+ if (attr) {
+ kfree(attr->kp.symbol_name);
+ kfree(attr);
+ }
+}
+
+static struct fei_attr *fei_attr_lookup(const char *sym)
+{
+ struct fei_attr *attr;
+
+ list_for_each_entry(attr, &fei_attr_list, list) {
+ if (!strcmp(attr->kp.symbol_name, sym))
+ return attr;
+ }
+
+ return NULL;
+}
+
+static bool fei_attr_is_valid(struct fei_attr *_attr)
+{
+ struct fei_attr *attr;
+
+ list_for_each_entry(attr, &fei_attr_list, list) {
+ if (attr == _attr)
+ return true;
+ }
+
+ return false;
+}
+
+static int fei_retval_set(void *data, u64 val)
+{
+ struct fei_attr *attr = data;
+ unsigned long retv = (unsigned long)val;
+ int err = 0;
+
+ mutex_lock(&fei_lock);
+ /*
+ * Since this operation can be done after retval file is removed,
+ * It is safer to check the attr is still valid before accessing
+ * its member.
+ */
+ if (!fei_attr_is_valid(attr)) {
+ err = -ENOENT;
+ goto out;
+ }
+
+ if (attr->kp.addr) {
+ if (adjust_error_retval((unsigned long)attr->kp.addr,
+ val) != retv)
+ err = -EINVAL;
+ }
+ if (!err)
+ attr->retval = val;
+out:
+ mutex_unlock(&fei_lock);
+
+ return err;
+}
+
+static int fei_retval_get(void *data, u64 *val)
+{
+ struct fei_attr *attr = data;
+ int err = 0;
+
+ mutex_lock(&fei_lock);
+ /* Here we also validate @attr to ensure it still exists. */
+ if (!fei_attr_is_valid(attr))
+ err = -ENOENT;
+ else
+ *val = attr->retval;
+ mutex_unlock(&fei_lock);
+
+ return err;
+}
+DEFINE_DEBUGFS_ATTRIBUTE(fei_retval_ops, fei_retval_get, fei_retval_set,
+ "%llx\n");
+
+static void fei_debugfs_add_attr(struct fei_attr *attr)
+{
+ struct dentry *dir;
+
+ dir = debugfs_create_dir(attr->kp.symbol_name, fei_debugfs_dir);
+
+ debugfs_create_file("retval", 0600, dir, attr, &fei_retval_ops);
+}
+
+static void fei_debugfs_remove_attr(struct fei_attr *attr)
+{
+ struct dentry *dir;
+
+ dir = debugfs_lookup(attr->kp.symbol_name, fei_debugfs_dir);
+ debugfs_remove_recursive(dir);
+}
+
+static int fei_kprobe_handler(struct kprobe *kp, struct pt_regs *regs)
+{
+ struct fei_attr *attr = container_of(kp, struct fei_attr, kp);
+
+ if (should_fail(&fei_fault_attr, 1)) {
+ regs_set_return_value(regs, attr->retval);
+ override_function_with_return(regs);
+ return 1;
+ }
+
+ return 0;
+}
+NOKPROBE_SYMBOL(fei_kprobe_handler)
+
+static void *fei_seq_start(struct seq_file *m, loff_t *pos)
+{
+ mutex_lock(&fei_lock);
+ return seq_list_start(&fei_attr_list, *pos);
+}
+
+static void fei_seq_stop(struct seq_file *m, void *v)
+{
+ mutex_unlock(&fei_lock);
+}
+
+static void *fei_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ return seq_list_next(v, &fei_attr_list, pos);
+}
+
+static int fei_seq_show(struct seq_file *m, void *v)
+{
+ struct fei_attr *attr = list_entry(v, struct fei_attr, list);
+
+ seq_printf(m, "%ps\n", attr->kp.addr);
+ return 0;
+}
+
+static const struct seq_operations fei_seq_ops = {
+ .start = fei_seq_start,
+ .next = fei_seq_next,
+ .stop = fei_seq_stop,
+ .show = fei_seq_show,
+};
+
+static int fei_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &fei_seq_ops);
+}
+
+static void fei_attr_remove(struct fei_attr *attr)
+{
+ fei_debugfs_remove_attr(attr);
+ unregister_kprobe(&attr->kp);
+ list_del(&attr->list);
+ fei_attr_free(attr);
+}
+
+static void fei_attr_remove_all(void)
+{
+ struct fei_attr *attr, *n;
+
+ list_for_each_entry_safe(attr, n, &fei_attr_list, list) {
+ fei_attr_remove(attr);
+ }
+}
+
+static ssize_t fei_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct fei_attr *attr;
+ unsigned long addr;
+ char *buf, *sym;
+ int ret;
+
+ /* cut off if it is too long */
+ if (count > KSYM_NAME_LEN)
+ count = KSYM_NAME_LEN;
+
+ buf = memdup_user_nul(buffer, count);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+
+ sym = strstrip(buf);
+
+ mutex_lock(&fei_lock);
+
+ /* Writing just spaces will remove all injection points */
+ if (sym[0] == '\0') {
+ fei_attr_remove_all();
+ ret = count;
+ goto out;
+ }
+ /* Writing !function will remove one injection point */
+ if (sym[0] == '!') {
+ attr = fei_attr_lookup(sym + 1);
+ if (!attr) {
+ ret = -ENOENT;
+ goto out;
+ }
+ fei_attr_remove(attr);
+ ret = count;
+ goto out;
+ }
+
+ addr = kallsyms_lookup_name(sym);
+ if (!addr) {
+ ret = -EINVAL;
+ goto out;
+ }
+ if (!within_error_injection_list(addr)) {
+ ret = -ERANGE;
+ goto out;
+ }
+ if (fei_attr_lookup(sym)) {
+ ret = -EBUSY;
+ goto out;
+ }
+ attr = fei_attr_new(sym, addr);
+ if (!attr) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ret = register_kprobe(&attr->kp);
+ if (ret) {
+ fei_attr_free(attr);
+ goto out;
+ }
+ fei_debugfs_add_attr(attr);
+ list_add_tail(&attr->list, &fei_attr_list);
+ ret = count;
+out:
+ mutex_unlock(&fei_lock);
+ kfree(buf);
+ return ret;
+}
+
+static const struct file_operations fei_ops = {
+ .open = fei_open,
+ .read = seq_read,
+ .write = fei_write,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int __init fei_debugfs_init(void)
+{
+ struct dentry *dir;
+
+ dir = fault_create_debugfs_attr("fail_function", NULL,
+ &fei_fault_attr);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+
+ /* injectable attribute is just a symlink of error_inject/list */
+ debugfs_create_symlink("injectable", dir, "../error_injection/list");
+
+ debugfs_create_file("inject", 0600, dir, NULL, &fei_ops);
+
+ fei_debugfs_dir = dir;
+
+ return 0;
+}
+
+late_initcall(fei_debugfs_init);