From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- drivers/net/netdevsim/bus.c | 537 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 537 insertions(+) create mode 100644 drivers/net/netdevsim/bus.c (limited to 'drivers/net/netdevsim/bus.c') diff --git a/drivers/net/netdevsim/bus.c b/drivers/net/netdevsim/bus.c new file mode 100644 index 000000000..5c55c3084 --- /dev/null +++ b/drivers/net/netdevsim/bus.c @@ -0,0 +1,537 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2017 Netronome Systems, Inc. + * Copyright (C) 2019 Mellanox Technologies. All rights reserved + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "netdevsim.h" + +static DEFINE_IDA(nsim_bus_dev_ids); +static LIST_HEAD(nsim_bus_dev_list); +static DEFINE_MUTEX(nsim_bus_dev_list_lock); +static bool nsim_bus_enable; +static refcount_t nsim_bus_devs; /* Including the bus itself. */ +static DECLARE_COMPLETION(nsim_bus_devs_released); + +static struct nsim_bus_dev *to_nsim_bus_dev(struct device *dev) +{ + return container_of(dev, struct nsim_bus_dev, dev); +} + +static ssize_t +nsim_bus_dev_numvfs_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); + unsigned int num_vfs; + int ret; + + ret = kstrtouint(buf, 0, &num_vfs); + if (ret) + return ret; + + device_lock(dev); + ret = -ENOENT; + if (dev_get_drvdata(dev)) + ret = nsim_drv_configure_vfs(nsim_bus_dev, num_vfs); + device_unlock(dev); + + return ret ? ret : count; +} + +static ssize_t +nsim_bus_dev_numvfs_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); + + return sprintf(buf, "%u\n", nsim_bus_dev->num_vfs); +} + +static struct device_attribute nsim_bus_dev_numvfs_attr = + __ATTR(sriov_numvfs, 0664, nsim_bus_dev_numvfs_show, + nsim_bus_dev_numvfs_store); + +static ssize_t +new_port_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); + u8 eth_addr[ETH_ALEN] = {}; + unsigned int port_index; + bool addr_set = false; + int ret; + + /* Prevent to use nsim_bus_dev before initialization. */ + if (!smp_load_acquire(&nsim_bus_dev->init)) + return -EBUSY; + + ret = sscanf(buf, "%u %hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &port_index, + ð_addr[0], ð_addr[1], ð_addr[2], ð_addr[3], + ð_addr[4], ð_addr[5]); + switch (ret) { + case 7: + if (!is_valid_ether_addr(eth_addr)) { + pr_err("The supplied perm_addr is not a valid MAC address\n"); + return -EINVAL; + } + addr_set = true; + fallthrough; + case 1: + break; + default: + pr_err("Format for adding new port is \"id [perm_addr]\" (uint MAC).\n"); + return -EINVAL; + } + + ret = nsim_drv_port_add(nsim_bus_dev, NSIM_DEV_PORT_TYPE_PF, port_index, + addr_set ? eth_addr : NULL); + return ret ? ret : count; +} + +static struct device_attribute nsim_bus_dev_new_port_attr = __ATTR_WO(new_port); + +static ssize_t +del_port_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); + unsigned int port_index; + int ret; + + /* Prevent to use nsim_bus_dev before initialization. */ + if (!smp_load_acquire(&nsim_bus_dev->init)) + return -EBUSY; + ret = kstrtouint(buf, 0, &port_index); + if (ret) + return ret; + + ret = nsim_drv_port_del(nsim_bus_dev, NSIM_DEV_PORT_TYPE_PF, port_index); + return ret ? ret : count; +} + +static struct device_attribute nsim_bus_dev_del_port_attr = __ATTR_WO(del_port); + +static struct attribute *nsim_bus_dev_attrs[] = { + &nsim_bus_dev_numvfs_attr.attr, + &nsim_bus_dev_new_port_attr.attr, + &nsim_bus_dev_del_port_attr.attr, + NULL, +}; + +static const struct attribute_group nsim_bus_dev_attr_group = { + .attrs = nsim_bus_dev_attrs, +}; + +static const struct attribute_group *nsim_bus_dev_attr_groups[] = { + &nsim_bus_dev_attr_group, + NULL, +}; + +static void nsim_bus_dev_release(struct device *dev) +{ + struct nsim_bus_dev *nsim_bus_dev; + + nsim_bus_dev = container_of(dev, struct nsim_bus_dev, dev); + kfree(nsim_bus_dev); + if (refcount_dec_and_test(&nsim_bus_devs)) + complete(&nsim_bus_devs_released); +} + +static const struct device_type nsim_bus_dev_type = { + .groups = nsim_bus_dev_attr_groups, + .release = nsim_bus_dev_release, +}; + +static struct nsim_bus_dev * +nsim_bus_dev_new(unsigned int id, unsigned int port_count, unsigned int num_queues); + +static ssize_t +new_device_store(const struct bus_type *bus, const char *buf, size_t count) +{ + unsigned int id, port_count, num_queues; + struct nsim_bus_dev *nsim_bus_dev; + int err; + + err = sscanf(buf, "%u %u %u", &id, &port_count, &num_queues); + switch (err) { + case 1: + port_count = 1; + fallthrough; + case 2: + num_queues = 1; + fallthrough; + case 3: + if (id > INT_MAX) { + pr_err("Value of \"id\" is too big.\n"); + return -EINVAL; + } + break; + default: + pr_err("Format for adding new device is \"id port_count num_queues\" (uint uint uint).\n"); + return -EINVAL; + } + + mutex_lock(&nsim_bus_dev_list_lock); + /* Prevent to use resource before initialization. */ + if (!smp_load_acquire(&nsim_bus_enable)) { + err = -EBUSY; + goto err; + } + + nsim_bus_dev = nsim_bus_dev_new(id, port_count, num_queues); + if (IS_ERR(nsim_bus_dev)) { + err = PTR_ERR(nsim_bus_dev); + goto err; + } + + refcount_inc(&nsim_bus_devs); + /* Allow using nsim_bus_dev */ + smp_store_release(&nsim_bus_dev->init, true); + + list_add_tail(&nsim_bus_dev->list, &nsim_bus_dev_list); + mutex_unlock(&nsim_bus_dev_list_lock); + + return count; +err: + mutex_unlock(&nsim_bus_dev_list_lock); + return err; +} +static BUS_ATTR_WO(new_device); + +static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev); + +static ssize_t +del_device_store(const struct bus_type *bus, const char *buf, size_t count) +{ + struct nsim_bus_dev *nsim_bus_dev, *tmp; + unsigned int id; + int err; + + err = sscanf(buf, "%u", &id); + switch (err) { + case 1: + if (id > INT_MAX) { + pr_err("Value of \"id\" is too big.\n"); + return -EINVAL; + } + break; + default: + pr_err("Format for deleting device is \"id\" (uint).\n"); + return -EINVAL; + } + + err = -ENOENT; + mutex_lock(&nsim_bus_dev_list_lock); + /* Prevent to use resource before initialization. */ + if (!smp_load_acquire(&nsim_bus_enable)) { + mutex_unlock(&nsim_bus_dev_list_lock); + return -EBUSY; + } + list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) { + if (nsim_bus_dev->dev.id != id) + continue; + list_del(&nsim_bus_dev->list); + nsim_bus_dev_del(nsim_bus_dev); + err = 0; + break; + } + mutex_unlock(&nsim_bus_dev_list_lock); + return !err ? count : err; +} +static BUS_ATTR_WO(del_device); + +static ssize_t link_device_store(const struct bus_type *bus, const char *buf, size_t count) +{ + struct netdevsim *nsim_a, *nsim_b, *peer; + struct net_device *dev_a, *dev_b; + unsigned int ifidx_a, ifidx_b; + int netnsfd_a, netnsfd_b, err; + struct net *ns_a, *ns_b; + + err = sscanf(buf, "%d:%u %d:%u", &netnsfd_a, &ifidx_a, &netnsfd_b, + &ifidx_b); + if (err != 4) { + pr_err("Format for linking two devices is \"netnsfd_a:ifidx_a netnsfd_b:ifidx_b\" (int uint int uint).\n"); + return -EINVAL; + } + + ns_a = get_net_ns_by_fd(netnsfd_a); + if (IS_ERR(ns_a)) { + pr_err("Could not find netns with fd: %d\n", netnsfd_a); + return -EINVAL; + } + + ns_b = get_net_ns_by_fd(netnsfd_b); + if (IS_ERR(ns_b)) { + pr_err("Could not find netns with fd: %d\n", netnsfd_b); + put_net(ns_a); + return -EINVAL; + } + + err = -EINVAL; + rtnl_lock(); + dev_a = __dev_get_by_index(ns_a, ifidx_a); + if (!dev_a) { + pr_err("Could not find device with ifindex %u in netnsfd %d\n", + ifidx_a, netnsfd_a); + goto out_err; + } + + if (!netdev_is_nsim(dev_a)) { + pr_err("Device with ifindex %u in netnsfd %d is not a netdevsim\n", + ifidx_a, netnsfd_a); + goto out_err; + } + + dev_b = __dev_get_by_index(ns_b, ifidx_b); + if (!dev_b) { + pr_err("Could not find device with ifindex %u in netnsfd %d\n", + ifidx_b, netnsfd_b); + goto out_err; + } + + if (!netdev_is_nsim(dev_b)) { + pr_err("Device with ifindex %u in netnsfd %d is not a netdevsim\n", + ifidx_b, netnsfd_b); + goto out_err; + } + + if (dev_a == dev_b) { + pr_err("Cannot link a netdevsim to itself\n"); + goto out_err; + } + + err = -EBUSY; + nsim_a = netdev_priv(dev_a); + peer = rtnl_dereference(nsim_a->peer); + if (peer) { + pr_err("Netdevsim %d:%u is already linked\n", netnsfd_a, + ifidx_a); + goto out_err; + } + + nsim_b = netdev_priv(dev_b); + peer = rtnl_dereference(nsim_b->peer); + if (peer) { + pr_err("Netdevsim %d:%u is already linked\n", netnsfd_b, + ifidx_b); + goto out_err; + } + + err = 0; + rcu_assign_pointer(nsim_a->peer, nsim_b); + rcu_assign_pointer(nsim_b->peer, nsim_a); + + if (netif_running(dev_a) && netif_running(dev_b)) { + netif_carrier_on(dev_a); + netif_carrier_on(dev_b); + } + +out_err: + put_net(ns_b); + put_net(ns_a); + rtnl_unlock(); + + return !err ? count : err; +} +static BUS_ATTR_WO(link_device); + +static ssize_t unlink_device_store(const struct bus_type *bus, const char *buf, size_t count) +{ + struct netdevsim *nsim, *peer; + struct net_device *dev; + unsigned int ifidx; + int netnsfd, err; + struct net *ns; + + err = sscanf(buf, "%u:%u", &netnsfd, &ifidx); + if (err != 2) { + pr_err("Format for unlinking a device is \"netnsfd:ifidx\" (int uint).\n"); + return -EINVAL; + } + + ns = get_net_ns_by_fd(netnsfd); + if (IS_ERR(ns)) { + pr_err("Could not find netns with fd: %d\n", netnsfd); + return -EINVAL; + } + + err = -EINVAL; + rtnl_lock(); + dev = __dev_get_by_index(ns, ifidx); + if (!dev) { + pr_err("Could not find device with ifindex %u in netnsfd %d\n", + ifidx, netnsfd); + goto out_put_netns; + } + + if (!netdev_is_nsim(dev)) { + pr_err("Device with ifindex %u in netnsfd %d is not a netdevsim\n", + ifidx, netnsfd); + goto out_put_netns; + } + + nsim = netdev_priv(dev); + peer = rtnl_dereference(nsim->peer); + if (!peer) + goto out_put_netns; + + netif_carrier_off(dev); + netif_carrier_off(peer->netdev); + + err = 0; + RCU_INIT_POINTER(nsim->peer, NULL); + RCU_INIT_POINTER(peer->peer, NULL); + synchronize_net(); + netif_tx_wake_all_queues(dev); + netif_tx_wake_all_queues(peer->netdev); + +out_put_netns: + put_net(ns); + rtnl_unlock(); + + return !err ? count : err; +} +static BUS_ATTR_WO(unlink_device); + +static struct attribute *nsim_bus_attrs[] = { + &bus_attr_new_device.attr, + &bus_attr_del_device.attr, + &bus_attr_link_device.attr, + &bus_attr_unlink_device.attr, + NULL +}; +ATTRIBUTE_GROUPS(nsim_bus); + +static int nsim_bus_probe(struct device *dev) +{ + struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); + + return nsim_drv_probe(nsim_bus_dev); +} + +static void nsim_bus_remove(struct device *dev) +{ + struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); + + nsim_drv_remove(nsim_bus_dev); +} + +static int nsim_num_vf(struct device *dev) +{ + struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev); + + return nsim_bus_dev->num_vfs; +} + +static const struct bus_type nsim_bus = { + .name = DRV_NAME, + .dev_name = DRV_NAME, + .bus_groups = nsim_bus_groups, + .probe = nsim_bus_probe, + .remove = nsim_bus_remove, + .num_vf = nsim_num_vf, +}; + +static struct nsim_bus_dev * +nsim_bus_dev_new(unsigned int id, unsigned int port_count, unsigned int num_queues) +{ + struct nsim_bus_dev *nsim_bus_dev; + int err; + + nsim_bus_dev = kzalloc_obj(*nsim_bus_dev); + if (!nsim_bus_dev) + return ERR_PTR(-ENOMEM); + + err = ida_alloc_range(&nsim_bus_dev_ids, id, id, GFP_KERNEL); + if (err < 0) + goto err_nsim_bus_dev_free; + nsim_bus_dev->dev.id = err; + nsim_bus_dev->dev.bus = &nsim_bus; + nsim_bus_dev->dev.type = &nsim_bus_dev_type; + nsim_bus_dev->port_count = port_count; + nsim_bus_dev->num_queues = num_queues; + nsim_bus_dev->initial_net = current->nsproxy->net_ns; + /* Disallow using nsim_bus_dev */ + smp_store_release(&nsim_bus_dev->init, false); + + err = device_register(&nsim_bus_dev->dev); + if (err) + goto err_nsim_bus_dev_id_free; + + return nsim_bus_dev; + +err_nsim_bus_dev_id_free: + ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id); + put_device(&nsim_bus_dev->dev); + nsim_bus_dev = NULL; +err_nsim_bus_dev_free: + kfree(nsim_bus_dev); + return ERR_PTR(err); +} + +static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev) +{ + /* Disallow using nsim_bus_dev */ + smp_store_release(&nsim_bus_dev->init, false); + ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id); + device_unregister(&nsim_bus_dev->dev); +} + +static struct device_driver nsim_driver = { + .name = DRV_NAME, + .bus = &nsim_bus, + .owner = THIS_MODULE, +}; + +int nsim_bus_init(void) +{ + int err; + + err = bus_register(&nsim_bus); + if (err) + return err; + err = driver_register(&nsim_driver); + if (err) + goto err_bus_unregister; + refcount_set(&nsim_bus_devs, 1); + /* Allow using resources */ + smp_store_release(&nsim_bus_enable, true); + return 0; + +err_bus_unregister: + bus_unregister(&nsim_bus); + return err; +} + +void nsim_bus_exit(void) +{ + struct nsim_bus_dev *nsim_bus_dev, *tmp; + + /* Disallow using resources */ + smp_store_release(&nsim_bus_enable, false); + if (refcount_dec_and_test(&nsim_bus_devs)) + complete(&nsim_bus_devs_released); + + mutex_lock(&nsim_bus_dev_list_lock); + list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) { + list_del(&nsim_bus_dev->list); + nsim_bus_dev_del(nsim_bus_dev); + } + mutex_unlock(&nsim_bus_dev_list_lock); + + wait_for_completion(&nsim_bus_devs_released); + + driver_unregister(&nsim_driver); + bus_unregister(&nsim_bus); +} -- cgit v1.3.1