/* user_defined.c: user defined key type * * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include #include #include #include #include #include #include #include "internal.h" static int logon_vet_description(const char *desc); /* * user defined keys take an arbitrary string as the description and an * arbitrary blob of data as the payload */ struct key_type key_type_user = { .name = "user", .preparse = user_preparse, .free_preparse = user_free_preparse, .instantiate = generic_key_instantiate, .update = user_update, .revoke = user_revoke, .destroy = user_destroy, .describe = user_describe, .read = user_read, }; EXPORT_SYMBOL_GPL(key_type_user); /* * This key type is essentially the same as key_type_user, but it does * not define a .read op. This is suitable for storing username and * password pairs in the keyring that you do not want to be readable * from userspace. */ struct key_type key_type_logon = { .name = "logon", .preparse = user_preparse, .free_preparse = user_free_preparse, .instantiate = generic_key_instantiate, .update = user_update, .revoke = user_revoke, .destroy = user_destroy, .describe = user_describe, .vet_description = logon_vet_description, }; EXPORT_SYMBOL_GPL(key_type_logon); /* * Preparse a user defined key payload */ int user_preparse(struct key_preparsed_payload *prep) { struct user_key_payload *upayload; size_t datalen = prep->datalen; if (datalen <= 0 || datalen > 32767 || !prep->data) return -EINVAL; upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL); if (!upayload) return -ENOMEM; /* attach the data */ prep->quotalen = datalen; prep->payload.data[0] = upayload; upayload->datalen = datalen; memcpy(upayload->data, prep->data, datalen); return 0; } EXPORT_SYMBOL_GPL(user_preparse); /* * Free a preparse of a user defined key payload */ void user_free_preparse(struct key_preparsed_payload *prep) { kfree(prep->payload.data[0]); } EXPORT_SYMBOL_GPL(user_free_preparse); /* * update a user defined key * - the key's semaphore is write-locked */ int user_update(struct key *key, struct key_preparsed_payload *prep) { struct user_key_payload *zap = NULL; int ret; /* check the quota and attach the new data */ ret = key_payload_reserve(key, prep->datalen); if (ret < 0) return ret; /* attach the new data, displacing the old */ key->expiry = prep->expiry; if (!test_bit(KEY_FLAG_NEGATIVE, &key->flags)) zap = rcu_dereference_key(key); rcu_assign_keypointer(key, prep->payload.data[0]); prep->payload.data[0] = NULL; if (zap) kfree_rcu(zap, rcu); return ret; } EXPORT_SYMBOL_GPL(user_update); /* * dispose of the links from a revoked keyring * - called with the key sem write-locked */ void user_revoke(struct key *key) { struct user_key_payload *upayload = key->payload.data[0]; /* clear the quota */ key_payload_reserve(key, 0); if (upayload) { rcu_assign_keypointer(key, NULL); kfree_rcu(upayload, rcu); } } EXPORT_SYMBOL(user_revoke); /* * dispose of the data dangling from the corpse of a user key */ void user_destroy(struct key *key) { struct user_key_payload *upayload = key->payload.data[0]; kfree(upayload); } EXPORT_SYMBOL_GPL(user_destroy); /* * describe the user key */ void user_describe(const struct key *key, struct seq_file *m) { seq_puts(m, key->description); if (key_is_instantiated(key)) seq_printf(m, ": %u", key->datalen); } EXPORT_SYMBOL_GPL(user_describe); /* * read the key data * - the key's semaphore is read-locked */ long user_read(const struct key *key, char __user *buffer, size_t buflen) { const struct user_key_payload *upayload; long ret; upayload = user_key_payload(key); ret = upayload->datalen; /* we can return the data as is */ if (buffer && buflen > 0) { if (buflen > upayload->datalen) buflen = upayload->datalen; if (copy_to_user(buffer, upayload->data, buflen) != 0) ret = -EFAULT; } return ret; } EXPORT_SYMBOL_GPL(user_read); /* Vet the description for a "logon" key */ static int logon_vet_description(const char *desc) { char *p; /* require a "qualified" description string */ p = strchr(desc, ':'); if (!p) return -EINVAL; /* also reject description with ':' as first char */ if (p == desc) return -EINVAL; return 0; } authorSteven Rostedt (VMware) <rostedt@goodmis.org>2017-01-30 19:27:10 -0500 committerSteven Rostedt (VMware) <rostedt@goodmis.org>2017-01-31 09:13:49 -0500 commit79c6f448c8b79c321e4a1f31f98194e4f6b6cae7 (patch) tree370efda701f03cccf21e02bb1fdd3b852547d75c /sound/soc/samsung/h1940_uda1380.c parent0c744ea4f77d72b3dcebb7a8f2684633ec79be88 (diff)
tracing: Fix hwlat kthread migration
The hwlat tracer creates a kernel thread at start of the tracer. It is pinned to a single CPU and will move to the next CPU after each period of running. If the user modifies the migration thread's affinity, it will not change after that happens. The original code created the thread at the first instance it was called, but later was changed to destroy the thread after the tracer was finished, and would not be created until the next instance of the tracer was established. The code that initialized the affinity was only called on the initial instantiation of the tracer. After that, it was not initialized, and the previous affinity did not match the current newly created one, making it appear that the user modified the thread's affinity when it did not, and the thread failed to migrate again. Cc: stable@vger.kernel.org Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'sound/soc/samsung/h1940_uda1380.c')