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 --- net/can/proc.c | 507 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 507 insertions(+) create mode 100644 net/can/proc.c (limited to 'net/can/proc.c') diff --git a/net/can/proc.c b/net/can/proc.c new file mode 100644 index 000000000..de4d05ae3 --- /dev/null +++ b/net/can/proc.c @@ -0,0 +1,507 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +/* + * proc.c - procfs support for Protocol family CAN core module + * + * Copyright (c) 2002-2007 Volkswagen Group Electronic Research + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Volkswagen nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * Alternatively, provided that this notice is retained in full, this + * software may be distributed under the terms of the GNU General + * Public License ("GPL") version 2, in which case the provisions of the + * GPL apply INSTEAD OF those given above. + * + * The provided data structures and external interfaces from this code + * are not restricted to be used by modules with a GPL compatible license. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + */ + +#include +#include +#include +#include +#include +#include +#include + +#include "af_can.h" + +/* + * proc filenames for the PF_CAN core + */ + +#define CAN_PROC_STATS "stats" +#define CAN_PROC_RESET_STATS "reset_stats" +#define CAN_PROC_RCVLIST_ALL "rcvlist_all" +#define CAN_PROC_RCVLIST_FIL "rcvlist_fil" +#define CAN_PROC_RCVLIST_INV "rcvlist_inv" +#define CAN_PROC_RCVLIST_SFF "rcvlist_sff" +#define CAN_PROC_RCVLIST_EFF "rcvlist_eff" +#define CAN_PROC_RCVLIST_ERR "rcvlist_err" + +static int user_reset; + +static const char rx_list_name[][8] = { + [RX_ERR] = "rx_err", + [RX_ALL] = "rx_all", + [RX_FIL] = "rx_fil", + [RX_INV] = "rx_inv", +}; + +/* + * af_can statistics stuff + */ + +static void can_init_stats(struct net *net) +{ + struct can_pkg_stats *pkg_stats = net->can.pkg_stats; + struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats; + /* + * This memset function is called from a timer context (when + * can_stattimer is active which is the default) OR in a process + * context (reading the proc_fs when can_stattimer is disabled). + */ + memset(pkg_stats, 0, sizeof(struct can_pkg_stats)); + pkg_stats->jiffies_init = jiffies; + + rcv_lists_stats->stats_reset++; + + if (user_reset) { + user_reset = 0; + rcv_lists_stats->user_reset++; + } +} + +static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif, + unsigned long count) +{ + if (oldjif == newjif) + return 0; + + /* see can_stat_update() - this should NEVER happen! */ + if (count > (ULONG_MAX / HZ)) { + printk(KERN_ERR "can: calc_rate: count exceeded! %ld\n", + count); + return 99999999; + } + + return (count * HZ) / (newjif - oldjif); +} + +void can_stat_update(struct timer_list *t) +{ + struct net *net = timer_container_of(net, t, can.stattimer); + struct can_pkg_stats *pkg_stats = net->can.pkg_stats; + unsigned long j = jiffies; /* snapshot */ + + long rx_frames = atomic_long_read(&pkg_stats->rx_frames); + long tx_frames = atomic_long_read(&pkg_stats->tx_frames); + long matches = atomic_long_read(&pkg_stats->matches); + long rx_frames_delta = atomic_long_read(&pkg_stats->rx_frames_delta); + long tx_frames_delta = atomic_long_read(&pkg_stats->tx_frames_delta); + long matches_delta = atomic_long_read(&pkg_stats->matches_delta); + + /* restart counting in timer context on user request */ + if (user_reset) + can_init_stats(net); + + /* restart counting on jiffies overflow */ + if (j < pkg_stats->jiffies_init) + can_init_stats(net); + + /* prevent overflow in calc_rate() */ + if (rx_frames > (LONG_MAX / HZ)) + can_init_stats(net); + + /* prevent overflow in calc_rate() */ + if (tx_frames > (LONG_MAX / HZ)) + can_init_stats(net); + + /* matches overflow - very improbable */ + if (matches > (LONG_MAX / 100)) + can_init_stats(net); + + /* calc total values */ + if (rx_frames) + pkg_stats->total_rx_match_ratio = (matches * 100) / rx_frames; + + pkg_stats->total_tx_rate = calc_rate(pkg_stats->jiffies_init, j, + tx_frames); + pkg_stats->total_rx_rate = calc_rate(pkg_stats->jiffies_init, j, + rx_frames); + + /* calc current values */ + if (rx_frames_delta) + pkg_stats->current_rx_match_ratio = + (matches_delta * 100) / rx_frames_delta; + + pkg_stats->current_tx_rate = calc_rate(0, HZ, tx_frames_delta); + pkg_stats->current_rx_rate = calc_rate(0, HZ, rx_frames_delta); + + /* check / update maximum values */ + if (pkg_stats->max_tx_rate < pkg_stats->current_tx_rate) + pkg_stats->max_tx_rate = pkg_stats->current_tx_rate; + + if (pkg_stats->max_rx_rate < pkg_stats->current_rx_rate) + pkg_stats->max_rx_rate = pkg_stats->current_rx_rate; + + if (pkg_stats->max_rx_match_ratio < pkg_stats->current_rx_match_ratio) + pkg_stats->max_rx_match_ratio = pkg_stats->current_rx_match_ratio; + + /* clear values for 'current rate' calculation */ + atomic_long_set(&pkg_stats->tx_frames_delta, 0); + atomic_long_set(&pkg_stats->rx_frames_delta, 0); + atomic_long_set(&pkg_stats->matches_delta, 0); + + /* restart timer (one second) */ + mod_timer(&net->can.stattimer, round_jiffies(jiffies + HZ)); +} + +/* + * proc read functions + */ + +static void can_print_rcvlist(struct seq_file *m, struct hlist_head *rx_list, + struct net_device *dev) +{ + struct receiver *r; + + hlist_for_each_entry_rcu(r, rx_list, list) { + char *fmt = (r->can_id & CAN_EFF_FLAG)? + " %-5s %08x %08x %pK %pK %8ld %s\n" : + " %-5s %03x %08x %pK %pK %8ld %s\n"; + + seq_printf(m, fmt, DNAME(dev), r->can_id, r->mask, + r->func, r->data, atomic_long_read(&r->matches), + r->ident); + } +} + +static void can_print_recv_banner(struct seq_file *m) +{ + /* + * can1. 00000000 00000000 00000000 + * ....... 0 tp20 + */ + if (IS_ENABLED(CONFIG_64BIT)) + seq_puts(m, " device can_id can_mask function userdata matches ident\n"); + else + seq_puts(m, " device can_id can_mask function userdata matches ident\n"); +} + +static int can_stats_proc_show(struct seq_file *m, void *v) +{ + struct net *net = m->private; + struct can_pkg_stats *pkg_stats = net->can.pkg_stats; + struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats; + + seq_putc(m, '\n'); + seq_printf(m, " %8ld transmitted frames (TXF)\n", + atomic_long_read(&pkg_stats->tx_frames)); + seq_printf(m, " %8ld received frames (RXF)\n", + atomic_long_read(&pkg_stats->rx_frames)); + seq_printf(m, " %8ld matched frames (RXMF)\n", + atomic_long_read(&pkg_stats->matches)); + + seq_putc(m, '\n'); + + if (net->can.stattimer.function == can_stat_update) { + seq_printf(m, " %8ld %% total match ratio (RXMR)\n", + pkg_stats->total_rx_match_ratio); + + seq_printf(m, " %8ld frames/s total tx rate (TXR)\n", + pkg_stats->total_tx_rate); + seq_printf(m, " %8ld frames/s total rx rate (RXR)\n", + pkg_stats->total_rx_rate); + + seq_putc(m, '\n'); + + seq_printf(m, " %8ld %% current match ratio (CRXMR)\n", + pkg_stats->current_rx_match_ratio); + + seq_printf(m, " %8ld frames/s current tx rate (CTXR)\n", + pkg_stats->current_tx_rate); + seq_printf(m, " %8ld frames/s current rx rate (CRXR)\n", + pkg_stats->current_rx_rate); + + seq_putc(m, '\n'); + + seq_printf(m, " %8ld %% max match ratio (MRXMR)\n", + pkg_stats->max_rx_match_ratio); + + seq_printf(m, " %8ld frames/s max tx rate (MTXR)\n", + pkg_stats->max_tx_rate); + seq_printf(m, " %8ld frames/s max rx rate (MRXR)\n", + pkg_stats->max_rx_rate); + + seq_putc(m, '\n'); + } + + seq_printf(m, " %8ld current receive list entries (CRCV)\n", + rcv_lists_stats->rcv_entries); + seq_printf(m, " %8ld maximum receive list entries (MRCV)\n", + rcv_lists_stats->rcv_entries_max); + + if (rcv_lists_stats->stats_reset) + seq_printf(m, "\n %8ld statistic resets (STR)\n", + rcv_lists_stats->stats_reset); + + if (rcv_lists_stats->user_reset) + seq_printf(m, " %8ld user statistic resets (USTR)\n", + rcv_lists_stats->user_reset); + + seq_putc(m, '\n'); + return 0; +} + +static int can_reset_stats_proc_show(struct seq_file *m, void *v) +{ + struct net *net = m->private; + struct can_rcv_lists_stats *rcv_lists_stats = net->can.rcv_lists_stats; + struct can_pkg_stats *pkg_stats = net->can.pkg_stats; + + user_reset = 1; + + if (net->can.stattimer.function == can_stat_update) { + seq_printf(m, "Scheduled statistic reset #%ld.\n", + rcv_lists_stats->stats_reset + 1); + } else { + if (pkg_stats->jiffies_init != jiffies) + can_init_stats(net); + + seq_printf(m, "Performed statistic reset #%ld.\n", + rcv_lists_stats->stats_reset); + } + return 0; +} + +static inline void can_rcvlist_proc_show_one(struct seq_file *m, int idx, + struct net_device *dev, + struct can_dev_rcv_lists *dev_rcv_lists) +{ + if (!hlist_empty(&dev_rcv_lists->rx[idx])) { + can_print_recv_banner(m); + can_print_rcvlist(m, &dev_rcv_lists->rx[idx], dev); + } else + seq_printf(m, " (%s: no entry)\n", DNAME(dev)); + +} + +static int can_rcvlist_proc_show(struct seq_file *m, void *v) +{ + /* double cast to prevent GCC warning */ + int idx = (int)(long)pde_data(m->file->f_inode); + struct net_device *dev; + struct can_dev_rcv_lists *dev_rcv_lists; + struct net *net = m->private; + + seq_printf(m, "\nreceive list '%s':\n", rx_list_name[idx]); + + rcu_read_lock(); + + /* receive list for 'all' CAN devices (dev == NULL) */ + dev_rcv_lists = net->can.rx_alldev_list; + can_rcvlist_proc_show_one(m, idx, NULL, dev_rcv_lists); + + /* receive list for registered CAN devices */ + for_each_netdev_rcu(net, dev) { + struct can_ml_priv *can_ml = can_get_ml_priv(dev); + + if (can_ml) + can_rcvlist_proc_show_one(m, idx, dev, + &can_ml->dev_rcv_lists); + } + + rcu_read_unlock(); + + seq_putc(m, '\n'); + return 0; +} + +static inline void can_rcvlist_proc_show_array(struct seq_file *m, + struct net_device *dev, + struct hlist_head *rcv_array, + unsigned int rcv_array_sz) +{ + unsigned int i; + int all_empty = 1; + + /* check whether at least one list is non-empty */ + for (i = 0; i < rcv_array_sz; i++) + if (!hlist_empty(&rcv_array[i])) { + all_empty = 0; + break; + } + + if (!all_empty) { + can_print_recv_banner(m); + for (i = 0; i < rcv_array_sz; i++) { + if (!hlist_empty(&rcv_array[i])) + can_print_rcvlist(m, &rcv_array[i], dev); + } + } else + seq_printf(m, " (%s: no entry)\n", DNAME(dev)); +} + +static int can_rcvlist_sff_proc_show(struct seq_file *m, void *v) +{ + struct net_device *dev; + struct can_dev_rcv_lists *dev_rcv_lists; + struct net *net = m->private; + + /* RX_SFF */ + seq_puts(m, "\nreceive list 'rx_sff':\n"); + + rcu_read_lock(); + + /* sff receive list for 'all' CAN devices (dev == NULL) */ + dev_rcv_lists = net->can.rx_alldev_list; + can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_sff, + ARRAY_SIZE(dev_rcv_lists->rx_sff)); + + /* sff receive list for registered CAN devices */ + for_each_netdev_rcu(net, dev) { + struct can_ml_priv *can_ml = can_get_ml_priv(dev); + + if (can_ml) { + dev_rcv_lists = &can_ml->dev_rcv_lists; + can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_sff, + ARRAY_SIZE(dev_rcv_lists->rx_sff)); + } + } + + rcu_read_unlock(); + + seq_putc(m, '\n'); + return 0; +} + +static int can_rcvlist_eff_proc_show(struct seq_file *m, void *v) +{ + struct net_device *dev; + struct can_dev_rcv_lists *dev_rcv_lists; + struct net *net = m->private; + + /* RX_EFF */ + seq_puts(m, "\nreceive list 'rx_eff':\n"); + + rcu_read_lock(); + + /* eff receive list for 'all' CAN devices (dev == NULL) */ + dev_rcv_lists = net->can.rx_alldev_list; + can_rcvlist_proc_show_array(m, NULL, dev_rcv_lists->rx_eff, + ARRAY_SIZE(dev_rcv_lists->rx_eff)); + + /* eff receive list for registered CAN devices */ + for_each_netdev_rcu(net, dev) { + struct can_ml_priv *can_ml = can_get_ml_priv(dev); + + if (can_ml) { + dev_rcv_lists = &can_ml->dev_rcv_lists; + can_rcvlist_proc_show_array(m, dev, dev_rcv_lists->rx_eff, + ARRAY_SIZE(dev_rcv_lists->rx_eff)); + } + } + + rcu_read_unlock(); + + seq_putc(m, '\n'); + return 0; +} + +/* + * can_init_proc - create main CAN proc directory and procfs entries + */ +void can_init_proc(struct net *net) +{ + /* create /proc/net/can directory */ + net->can.proc_dir = proc_net_mkdir(net, "can", net->proc_net); + + if (!net->can.proc_dir) { + printk(KERN_INFO "can: failed to create /proc/net/can . " + "CONFIG_PROC_FS missing?\n"); + return; + } + + /* own procfs entries from the AF_CAN core */ + net->can.pde_stats = proc_create_net_single(CAN_PROC_STATS, 0644, + net->can.proc_dir, can_stats_proc_show, NULL); + net->can.pde_reset_stats = proc_create_net_single(CAN_PROC_RESET_STATS, + 0644, net->can.proc_dir, can_reset_stats_proc_show, + NULL); + net->can.pde_rcvlist_err = proc_create_net_single(CAN_PROC_RCVLIST_ERR, + 0644, net->can.proc_dir, can_rcvlist_proc_show, + (void *)RX_ERR); + net->can.pde_rcvlist_all = proc_create_net_single(CAN_PROC_RCVLIST_ALL, + 0644, net->can.proc_dir, can_rcvlist_proc_show, + (void *)RX_ALL); + net->can.pde_rcvlist_fil = proc_create_net_single(CAN_PROC_RCVLIST_FIL, + 0644, net->can.proc_dir, can_rcvlist_proc_show, + (void *)RX_FIL); + net->can.pde_rcvlist_inv = proc_create_net_single(CAN_PROC_RCVLIST_INV, + 0644, net->can.proc_dir, can_rcvlist_proc_show, + (void *)RX_INV); + net->can.pde_rcvlist_eff = proc_create_net_single(CAN_PROC_RCVLIST_EFF, + 0644, net->can.proc_dir, can_rcvlist_eff_proc_show, NULL); + net->can.pde_rcvlist_sff = proc_create_net_single(CAN_PROC_RCVLIST_SFF, + 0644, net->can.proc_dir, can_rcvlist_sff_proc_show, NULL); +} + +/* + * can_remove_proc - remove procfs entries and main CAN proc directory + */ +void can_remove_proc(struct net *net) +{ + if (!net->can.proc_dir) + return; + + if (net->can.pde_stats) + remove_proc_entry(CAN_PROC_STATS, net->can.proc_dir); + + if (net->can.pde_reset_stats) + remove_proc_entry(CAN_PROC_RESET_STATS, net->can.proc_dir); + + if (net->can.pde_rcvlist_err) + remove_proc_entry(CAN_PROC_RCVLIST_ERR, net->can.proc_dir); + + if (net->can.pde_rcvlist_all) + remove_proc_entry(CAN_PROC_RCVLIST_ALL, net->can.proc_dir); + + if (net->can.pde_rcvlist_fil) + remove_proc_entry(CAN_PROC_RCVLIST_FIL, net->can.proc_dir); + + if (net->can.pde_rcvlist_inv) + remove_proc_entry(CAN_PROC_RCVLIST_INV, net->can.proc_dir); + + if (net->can.pde_rcvlist_eff) + remove_proc_entry(CAN_PROC_RCVLIST_EFF, net->can.proc_dir); + + if (net->can.pde_rcvlist_sff) + remove_proc_entry(CAN_PROC_RCVLIST_SFF, net->can.proc_dir); + + remove_proc_entry("can", net->proc_net); +} -- cgit v1.3.1