mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-31 00:17:44 +00:00
dc55e35f9e
Right now, the mqueue sysctls take ipc namespaces into account in a rather hacky way. This works in most cases, but does not respect the user namespace. Within the user namespace, the user cannot change the /proc/sys/fs/mqueue/* parametres. This poses a problem in the rootless containers. To solve this I changed the implementation of the mqueue sysctls just like some other sysctls. So far, the changes do not provide additional access to files. This will be done in a future patch. v3: * Don't implemenet set_permissions to keep the current behavior. v2: * Fixed compilation problem if CONFIG_POSIX_MQUEUE_SYSCTL is not specified. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Alexey Gladkov <legion@kernel.org> Link: https://lkml.kernel.org/r/b0ccbb2489119f1f20c737cf1930c3a9c4e4243a.1644862280.git.legion@kernel.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
131 lines
3 KiB
C
131 lines
3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright (C) 2007 IBM Corporation
|
|
*
|
|
* Author: Cedric Le Goater <clg@fr.ibm.com>
|
|
*/
|
|
|
|
#include <linux/nsproxy.h>
|
|
#include <linux/ipc_namespace.h>
|
|
#include <linux/sysctl.h>
|
|
|
|
#include <linux/stat.h>
|
|
#include <linux/capability.h>
|
|
#include <linux/slab.h>
|
|
|
|
static int msg_max_limit_min = MIN_MSGMAX;
|
|
static int msg_max_limit_max = HARD_MSGMAX;
|
|
|
|
static int msg_maxsize_limit_min = MIN_MSGSIZEMAX;
|
|
static int msg_maxsize_limit_max = HARD_MSGSIZEMAX;
|
|
|
|
static struct ctl_table mq_sysctls[] = {
|
|
{
|
|
.procname = "queues_max",
|
|
.data = &init_ipc_ns.mq_queues_max,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
.procname = "msg_max",
|
|
.data = &init_ipc_ns.mq_msg_max,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &msg_max_limit_min,
|
|
.extra2 = &msg_max_limit_max,
|
|
},
|
|
{
|
|
.procname = "msgsize_max",
|
|
.data = &init_ipc_ns.mq_msgsize_max,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &msg_maxsize_limit_min,
|
|
.extra2 = &msg_maxsize_limit_max,
|
|
},
|
|
{
|
|
.procname = "msg_default",
|
|
.data = &init_ipc_ns.mq_msg_default,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &msg_max_limit_min,
|
|
.extra2 = &msg_max_limit_max,
|
|
},
|
|
{
|
|
.procname = "msgsize_default",
|
|
.data = &init_ipc_ns.mq_msgsize_default,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &msg_maxsize_limit_min,
|
|
.extra2 = &msg_maxsize_limit_max,
|
|
},
|
|
{}
|
|
};
|
|
|
|
static struct ctl_table_set *set_lookup(struct ctl_table_root *root)
|
|
{
|
|
return ¤t->nsproxy->ipc_ns->mq_set;
|
|
}
|
|
|
|
static int set_is_seen(struct ctl_table_set *set)
|
|
{
|
|
return ¤t->nsproxy->ipc_ns->mq_set == set;
|
|
}
|
|
|
|
static struct ctl_table_root set_root = {
|
|
.lookup = set_lookup,
|
|
};
|
|
|
|
bool setup_mq_sysctls(struct ipc_namespace *ns)
|
|
{
|
|
struct ctl_table *tbl;
|
|
|
|
setup_sysctl_set(&ns->mq_set, &set_root, set_is_seen);
|
|
|
|
tbl = kmemdup(mq_sysctls, sizeof(mq_sysctls), GFP_KERNEL);
|
|
if (tbl) {
|
|
int i;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(mq_sysctls); i++) {
|
|
if (tbl[i].data == &init_ipc_ns.mq_queues_max)
|
|
tbl[i].data = &ns->mq_queues_max;
|
|
|
|
else if (tbl[i].data == &init_ipc_ns.mq_msg_max)
|
|
tbl[i].data = &ns->mq_msg_max;
|
|
|
|
else if (tbl[i].data == &init_ipc_ns.mq_msgsize_max)
|
|
tbl[i].data = &ns->mq_msgsize_max;
|
|
|
|
else if (tbl[i].data == &init_ipc_ns.mq_msg_default)
|
|
tbl[i].data = &ns->mq_msg_default;
|
|
|
|
else if (tbl[i].data == &init_ipc_ns.mq_msgsize_default)
|
|
tbl[i].data = &ns->mq_msgsize_default;
|
|
else
|
|
tbl[i].data = NULL;
|
|
}
|
|
|
|
ns->mq_sysctls = __register_sysctl_table(&ns->mq_set, "fs/mqueue", tbl);
|
|
}
|
|
if (!ns->mq_sysctls) {
|
|
kfree(tbl);
|
|
retire_sysctl_set(&ns->mq_set);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
void retire_mq_sysctls(struct ipc_namespace *ns)
|
|
{
|
|
struct ctl_table *tbl;
|
|
|
|
tbl = ns->mq_sysctls->ctl_table_arg;
|
|
unregister_sysctl_table(ns->mq_sysctls);
|
|
retire_sysctl_set(&ns->mq_set);
|
|
kfree(tbl);
|
|
}
|