From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- fs/smb/client/netlink.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 94 insertions(+) create mode 100644 fs/smb/client/netlink.c (limited to 'fs/smb/client/netlink.c') diff --git a/fs/smb/client/netlink.c b/fs/smb/client/netlink.c new file mode 100644 index 000000000..0dd10913c --- /dev/null +++ b/fs/smb/client/netlink.c @@ -0,0 +1,94 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Netlink routines for CIFS + * + * Copyright (c) 2020 Samuel Cabrero + */ + +#include +#include + +#include "netlink.h" +#include "cifsglob.h" +#include "cifs_debug.h" +#include "cifs_swn.h" + +static const struct nla_policy cifs_genl_policy[CIFS_GENL_ATTR_MAX + 1] = { + [CIFS_GENL_ATTR_SWN_REGISTRATION_ID] = { .type = NLA_U32 }, + [CIFS_GENL_ATTR_SWN_NET_NAME] = { .type = NLA_STRING }, + [CIFS_GENL_ATTR_SWN_SHARE_NAME] = { .type = NLA_STRING }, + [CIFS_GENL_ATTR_SWN_IP] = { .len = sizeof(struct sockaddr_storage) }, + [CIFS_GENL_ATTR_SWN_NET_NAME_NOTIFY] = { .type = NLA_FLAG }, + [CIFS_GENL_ATTR_SWN_SHARE_NAME_NOTIFY] = { .type = NLA_FLAG }, + [CIFS_GENL_ATTR_SWN_IP_NOTIFY] = { .type = NLA_FLAG }, + [CIFS_GENL_ATTR_SWN_KRB_AUTH] = { .type = NLA_FLAG }, + [CIFS_GENL_ATTR_SWN_USER_NAME] = { .type = NLA_STRING }, + [CIFS_GENL_ATTR_SWN_PASSWORD] = { .type = NLA_STRING }, + [CIFS_GENL_ATTR_SWN_DOMAIN_NAME] = { .type = NLA_STRING }, + [CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE] = { .type = NLA_U32 }, + [CIFS_GENL_ATTR_SWN_RESOURCE_STATE] = { .type = NLA_U32 }, + [CIFS_GENL_ATTR_SWN_RESOURCE_NAME] = { .type = NLA_STRING}, +}; + +static const struct genl_ops cifs_genl_ops[] = { + { + .cmd = CIFS_GENL_CMD_SWN_NOTIFY, + .flags = GENL_ADMIN_PERM, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, + .doit = cifs_swn_notify, + }, +}; + +static const struct genl_multicast_group cifs_genl_mcgrps[] = { + [CIFS_GENL_MCGRP_SWN] = { + .name = CIFS_GENL_MCGRP_SWN_NAME, + .flags = GENL_MCAST_CAP_NET_ADMIN, + }, +}; + +struct genl_family cifs_genl_family = { + .name = CIFS_GENL_NAME, + .version = CIFS_GENL_VERSION, + .hdrsize = 0, + .maxattr = CIFS_GENL_ATTR_MAX, + .module = THIS_MODULE, + .policy = cifs_genl_policy, + .ops = cifs_genl_ops, + .n_ops = ARRAY_SIZE(cifs_genl_ops), + .resv_start_op = CIFS_GENL_CMD_SWN_NOTIFY + 1, + .mcgrps = cifs_genl_mcgrps, + .n_mcgrps = ARRAY_SIZE(cifs_genl_mcgrps), +}; + +/** + * cifs_genl_init - Register generic netlink family + * + * Return zero if initialized successfully, otherwise non-zero. + */ +int cifs_genl_init(void) +{ + int ret; + + ret = genl_register_family(&cifs_genl_family); + if (ret < 0) { + cifs_dbg(VFS, "%s: failed to register netlink family\n", + __func__); + return ret; + } + + return 0; +} + +/** + * cifs_genl_exit - Unregister generic netlink family + */ +void cifs_genl_exit(void) +{ + int ret; + + ret = genl_unregister_family(&cifs_genl_family); + if (ret < 0) { + cifs_dbg(VFS, "%s: failed to unregister netlink family\n", + __func__); + } +} -- cgit v1.3.1