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-rw-r--r--kernel/taskstats.c114
1 files changed, 65 insertions, 49 deletions
diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index 4e62a4a8fa91..0cd680ccc7e5 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -1,24 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* taskstats.c - Export per-task statistics to userland
*
* Copyright (C) Shailabh Nagar, IBM Corp. 2006
* (C) Balbir Singh, IBM Corp. 2006
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
*/
#include <linux/kernel.h>
#include <linux/taskstats_kern.h>
#include <linux/tsacct_kern.h>
+#include <linux/acct.h>
#include <linux/delayacct.h>
#include <linux/cpumask.h>
#include <linux/percpu.h>
@@ -44,17 +35,13 @@ struct kmem_cache *taskstats_cache;
static struct genl_family family;
-static const struct nla_policy taskstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1] = {
+static const struct nla_policy taskstats_cmd_get_policy[] = {
[TASKSTATS_CMD_ATTR_PID] = { .type = NLA_U32 },
[TASKSTATS_CMD_ATTR_TGID] = { .type = NLA_U32 },
[TASKSTATS_CMD_ATTR_REGISTER_CPUMASK] = { .type = NLA_STRING },
[TASKSTATS_CMD_ATTR_DEREGISTER_CPUMASK] = { .type = NLA_STRING },};
-/*
- * We have to use TASKSTATS_CMD_ATTR_MAX here, it is the maxattr in the family.
- * Make sure they are always aligned.
- */
-static const struct nla_policy cgroupstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1] = {
+static const struct nla_policy cgroupstats_cmd_get_policy[] = {
[CGROUPSTATS_CMD_ATTR_FD] = { .type = NLA_U32 },
};
@@ -127,13 +114,14 @@ static void send_cpu_listeners(struct sk_buff *skb,
struct listener *s, *tmp;
struct sk_buff *skb_next, *skb_cur = skb;
void *reply = genlmsg_data(genlhdr);
- int rc, delcount = 0;
+ int delcount = 0;
genlmsg_end(skb, reply);
- rc = 0;
down_read(&listeners->sem);
list_for_each_entry(s, &listeners->list, list) {
+ int rc;
+
skb_next = NULL;
if (!list_is_last(&s->list, &listeners->list)) {
skb_next = skb_clone(skb_cur, GFP_KERNEL);
@@ -166,6 +154,23 @@ static void send_cpu_listeners(struct sk_buff *skb,
up_write(&listeners->sem);
}
+static void exe_add_tsk(struct taskstats *stats, struct task_struct *tsk)
+{
+ /* No idea if I'm allowed to access that here, now. */
+ struct file *exe_file = get_task_exe_file(tsk);
+
+ if (exe_file) {
+ /* Following cp_new_stat64() in stat.c . */
+ stats->ac_exe_dev =
+ huge_encode_dev(exe_file->f_inode->i_sb->s_dev);
+ stats->ac_exe_inode = exe_file->f_inode->i_ino;
+ fput(exe_file);
+ } else {
+ stats->ac_exe_dev = 0;
+ stats->ac_exe_inode = 0;
+ }
+}
+
static void fill_stats(struct user_namespace *user_ns,
struct pid_namespace *pid_ns,
struct task_struct *tsk, struct taskstats *stats)
@@ -188,6 +193,9 @@ static void fill_stats(struct user_namespace *user_ns,
/* fill in extended acct fields */
xacct_add_tsk(stats, tsk);
+
+ /* add executable info */
+ exe_add_tsk(stats, tsk);
}
static int fill_stats_for_pid(pid_t pid, struct taskstats *stats)
@@ -225,9 +233,8 @@ static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats)
else
memset(stats, 0, sizeof(*stats));
- tsk = first;
start_time = ktime_get_ns();
- do {
+ for_each_thread(first, tsk) {
if (tsk->exit_state)
continue;
/*
@@ -250,7 +257,7 @@ static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats)
stats->nvcsw += tsk->nvcsw;
stats->nivcsw += tsk->nivcsw;
- } while_each_thread(first, tsk);
+ }
unlock_task_sighand(first, &flags);
rc = 0;
@@ -360,7 +367,7 @@ static int parse(struct nlattr *na, struct cpumask *mask)
data = kmalloc(len, GFP_KERNEL);
if (!data)
return -ENOMEM;
- nla_strlcpy(data, na, len);
+ nla_strscpy(data, na, len);
ret = cpulist_parse(data, mask);
kfree(data);
return ret;
@@ -375,7 +382,7 @@ static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid)
? TASKSTATS_TYPE_AGGR_PID
: TASKSTATS_TYPE_AGGR_TGID;
- na = nla_nest_start(skb, aggr);
+ na = nla_nest_start_noflag(skb, aggr);
if (!na)
goto err;
@@ -404,15 +411,14 @@ static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
struct nlattr *na;
size_t size;
u32 fd;
- struct fd f;
na = info->attrs[CGROUPSTATS_CMD_ATTR_FD];
if (!na)
return -EINVAL;
fd = nla_get_u32(info->attrs[CGROUPSTATS_CMD_ATTR_FD]);
- f = fdget(fd);
- if (!f.file)
+ CLASS(fd, f)(fd);
+ if (fd_empty(f))
return 0;
size = nla_total_size(sizeof(struct cgroupstats));
@@ -420,30 +426,25 @@ static int cgroupstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
rc = prepare_reply(info, CGROUPSTATS_CMD_NEW, &rep_skb,
size);
if (rc < 0)
- goto err;
+ return rc;
na = nla_reserve(rep_skb, CGROUPSTATS_TYPE_CGROUP_STATS,
sizeof(struct cgroupstats));
if (na == NULL) {
nlmsg_free(rep_skb);
- rc = -EMSGSIZE;
- goto err;
+ return -EMSGSIZE;
}
stats = nla_data(na);
memset(stats, 0, sizeof(*stats));
- rc = cgroupstats_build(stats, f.file->f_path.dentry);
+ rc = cgroupstats_build(stats, fd_file(f)->f_path.dentry);
if (rc < 0) {
nlmsg_free(rep_skb);
- goto err;
+ return rc;
}
- rc = send_reply(rep_skb, info);
-
-err:
- fdput(f);
- return rc;
+ return send_reply(rep_skb, info);
}
static int cmd_attr_register_cpumask(struct genl_info *info)
@@ -564,25 +565,33 @@ static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
static struct taskstats *taskstats_tgid_alloc(struct task_struct *tsk)
{
struct signal_struct *sig = tsk->signal;
- struct taskstats *stats;
+ struct taskstats *stats_new, *stats;
- if (sig->stats || thread_group_empty(tsk))
- goto ret;
+ /* Pairs with smp_store_release() below. */
+ stats = smp_load_acquire(&sig->stats);
+ if (stats || thread_group_empty(tsk))
+ return stats;
/* No problem if kmem_cache_zalloc() fails */
- stats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
+ stats_new = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
spin_lock_irq(&tsk->sighand->siglock);
- if (!sig->stats) {
- sig->stats = stats;
- stats = NULL;
+ stats = sig->stats;
+ if (!stats) {
+ /*
+ * Pairs with smp_store_release() above and order the
+ * kmem_cache_zalloc().
+ */
+ smp_store_release(&sig->stats, stats_new);
+ stats = stats_new;
+ stats_new = NULL;
}
spin_unlock_irq(&tsk->sighand->siglock);
- if (stats)
- kmem_cache_free(taskstats_cache, stats);
-ret:
- return sig->stats;
+ if (stats_new)
+ kmem_cache_free(taskstats_cache, stats_new);
+
+ return stats;
}
/* Send pid data out on exit */
@@ -625,6 +634,8 @@ void taskstats_exit(struct task_struct *tsk, int group_dead)
goto err;
fill_stats(&init_user_ns, &init_pid_ns, tsk, stats);
+ if (group_dead)
+ stats->ac_flag |= AGROUP;
/*
* Doesn't matter if tsk is the leader or the last group member leaving
@@ -649,24 +660,29 @@ err:
static const struct genl_ops taskstats_ops[] = {
{
.cmd = TASKSTATS_CMD_GET,
+ .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
.doit = taskstats_user_cmd,
.policy = taskstats_cmd_get_policy,
+ .maxattr = ARRAY_SIZE(taskstats_cmd_get_policy) - 1,
.flags = GENL_ADMIN_PERM,
},
{
.cmd = CGROUPSTATS_CMD_GET,
+ .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
.doit = cgroupstats_user_cmd,
.policy = cgroupstats_cmd_get_policy,
+ .maxattr = ARRAY_SIZE(cgroupstats_cmd_get_policy) - 1,
},
};
static struct genl_family family __ro_after_init = {
.name = TASKSTATS_GENL_NAME,
.version = TASKSTATS_GENL_VERSION,
- .maxattr = TASKSTATS_CMD_ATTR_MAX,
.module = THIS_MODULE,
.ops = taskstats_ops,
.n_ops = ARRAY_SIZE(taskstats_ops),
+ .resv_start_op = CGROUPSTATS_CMD_GET + 1,
+ .netnsok = true,
};
/* Needed early in initialization */
generated by cgit (git 2.34.1) at 2025-12-22 09:29:23 +0000