kernel-fxtec-pro1x/include/linux/ipc_namespace.h
Davidlohr Bueso f3713fd9cf ipc,mqueue: remove limits for the amount of system-wide queues
Commit 93e6f119c0 ("ipc/mqueue: cleanup definition names and
locations") added global hardcoded limits to the amount of message
queues that can be created.  While these limits are per-namespace,
reality is that it ends up breaking userspace applications.
Historically users have, at least in theory, been able to create up to
INT_MAX queues, and limiting it to just 1024 is way too low and dramatic
for some workloads and use cases.  For instance, Madars reports:

 "This update imposes bad limits on our multi-process application.  As
  our app uses approaches that each process opens its own set of queues
  (usually something about 3-5 queues per process).  In some scenarios
  we might run up to 3000 processes or more (which of-course for linux
  is not a problem).  Thus we might need up to 9000 queues or more.  All
  processes run under one user."

Other affected users can be found in launchpad bug #1155695:
  https://bugs.launchpad.net/ubuntu/+source/manpages/+bug/1155695

Instead of increasing this limit, revert it entirely and fallback to the
original way of dealing queue limits -- where once a user's resource
limit is reached, and all memory is used, new queues cannot be created.

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Reported-by: Madars Vitolins <m@silodev.com>
Acked-by: Doug Ledford <dledford@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@vger.kernel.org>	[3.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-02-25 15:25:45 -08:00

179 lines
5.1 KiB
C

#ifndef __IPC_NAMESPACE_H__
#define __IPC_NAMESPACE_H__
#include <linux/err.h>
#include <linux/idr.h>
#include <linux/rwsem.h>
#include <linux/notifier.h>
#include <linux/nsproxy.h>
/*
* ipc namespace events
*/
#define IPCNS_MEMCHANGED 0x00000001 /* Notify lowmem size changed */
#define IPCNS_CREATED 0x00000002 /* Notify new ipc namespace created */
#define IPCNS_REMOVED 0x00000003 /* Notify ipc namespace removed */
#define IPCNS_CALLBACK_PRI 0
struct user_namespace;
struct ipc_ids {
int in_use;
unsigned short seq;
struct rw_semaphore rwsem;
struct idr ipcs_idr;
int next_id;
};
struct ipc_namespace {
atomic_t count;
struct ipc_ids ids[3];
int sem_ctls[4];
int used_sems;
unsigned int msg_ctlmax;
unsigned int msg_ctlmnb;
unsigned int msg_ctlmni;
atomic_t msg_bytes;
atomic_t msg_hdrs;
int auto_msgmni;
size_t shm_ctlmax;
size_t shm_ctlall;
unsigned long shm_tot;
int shm_ctlmni;
/*
* Defines whether IPC_RMID is forced for _all_ shm segments regardless
* of shmctl()
*/
int shm_rmid_forced;
struct notifier_block ipcns_nb;
/* The kern_mount of the mqueuefs sb. We take a ref on it */
struct vfsmount *mq_mnt;
/* # queues in this ns, protected by mq_lock */
unsigned int mq_queues_count;
/* next fields are set through sysctl */
unsigned int mq_queues_max; /* initialized to DFLT_QUEUESMAX */
unsigned int mq_msg_max; /* initialized to DFLT_MSGMAX */
unsigned int mq_msgsize_max; /* initialized to DFLT_MSGSIZEMAX */
unsigned int mq_msg_default;
unsigned int mq_msgsize_default;
/* user_ns which owns the ipc ns */
struct user_namespace *user_ns;
unsigned int proc_inum;
};
extern struct ipc_namespace init_ipc_ns;
extern atomic_t nr_ipc_ns;
extern spinlock_t mq_lock;
#ifdef CONFIG_SYSVIPC
extern int register_ipcns_notifier(struct ipc_namespace *);
extern int cond_register_ipcns_notifier(struct ipc_namespace *);
extern void unregister_ipcns_notifier(struct ipc_namespace *);
extern int ipcns_notify(unsigned long);
extern void shm_destroy_orphaned(struct ipc_namespace *ns);
#else /* CONFIG_SYSVIPC */
static inline int register_ipcns_notifier(struct ipc_namespace *ns)
{ return 0; }
static inline int cond_register_ipcns_notifier(struct ipc_namespace *ns)
{ return 0; }
static inline void unregister_ipcns_notifier(struct ipc_namespace *ns) { }
static inline int ipcns_notify(unsigned long l) { return 0; }
static inline void shm_destroy_orphaned(struct ipc_namespace *ns) {}
#endif /* CONFIG_SYSVIPC */
#ifdef CONFIG_POSIX_MQUEUE
extern int mq_init_ns(struct ipc_namespace *ns);
/*
* POSIX Message Queue default values:
*
* MIN_*: Lowest value an admin can set the maximum unprivileged limit to
* DFLT_*MAX: Default values for the maximum unprivileged limits
* DFLT_{MSG,MSGSIZE}: Default values used when the user doesn't supply
* an attribute to the open call and the queue must be created
* HARD_*: Highest value the maximums can be set to. These are enforced
* on CAP_SYS_RESOURCE apps as well making them inviolate (so make them
* suitably high)
*
* POSIX Requirements:
* Per app minimum openable message queues - 8. This does not map well
* to the fact that we limit the number of queues on a per namespace
* basis instead of a per app basis. So, make the default high enough
* that no given app should have a hard time opening 8 queues.
* Minimum maximum for HARD_MSGMAX - 32767. I bumped this to 65536.
* Minimum maximum for HARD_MSGSIZEMAX - POSIX is silent on this. However,
* we have run into a situation where running applications in the wild
* require this to be at least 5MB, and preferably 10MB, so I set the
* value to 16MB in hopes that this user is the worst of the bunch and
* the new maximum will handle anyone else. I may have to revisit this
* in the future.
*/
#define DFLT_QUEUESMAX 256
#define MIN_MSGMAX 1
#define DFLT_MSG 10U
#define DFLT_MSGMAX 10
#define HARD_MSGMAX 65536
#define MIN_MSGSIZEMAX 128
#define DFLT_MSGSIZE 8192U
#define DFLT_MSGSIZEMAX 8192
#define HARD_MSGSIZEMAX (16*1024*1024)
#else
static inline int mq_init_ns(struct ipc_namespace *ns) { return 0; }
#endif
#if defined(CONFIG_IPC_NS)
extern struct ipc_namespace *copy_ipcs(unsigned long flags,
struct user_namespace *user_ns, struct ipc_namespace *ns);
static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
{
if (ns)
atomic_inc(&ns->count);
return ns;
}
extern void put_ipc_ns(struct ipc_namespace *ns);
#else
static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
struct user_namespace *user_ns, struct ipc_namespace *ns)
{
if (flags & CLONE_NEWIPC)
return ERR_PTR(-EINVAL);
return ns;
}
static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
{
return ns;
}
static inline void put_ipc_ns(struct ipc_namespace *ns)
{
}
#endif
#ifdef CONFIG_POSIX_MQUEUE_SYSCTL
struct ctl_table_header;
extern struct ctl_table_header *mq_register_sysctl_table(void);
#else /* CONFIG_POSIX_MQUEUE_SYSCTL */
static inline struct ctl_table_header *mq_register_sysctl_table(void)
{
return NULL;
}
#endif /* CONFIG_POSIX_MQUEUE_SYSCTL */
#endif