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53dad6d3a8
Currently, IPC mechanisms do security and auditing related checks under RCU. However, since security modules can free the security structure, for example, through selinux_[sem,msg_queue,shm]_free_security(), we can race if the structure is freed before other tasks are done with it, creating a use-after-free condition. Manfred illustrates this nicely, for instance with shared mem and selinux: -> do_shmat calls rcu_read_lock() -> do_shmat calls shm_object_check(). Checks that the object is still valid - but doesn't acquire any locks. Then it returns. -> do_shmat calls security_shm_shmat (e.g. selinux_shm_shmat) -> selinux_shm_shmat calls ipc_has_perm() -> ipc_has_perm accesses ipc_perms->security shm_close() -> shm_close acquires rw_mutex & shm_lock -> shm_close calls shm_destroy -> shm_destroy calls security_shm_free (e.g. selinux_shm_free_security) -> selinux_shm_free_security calls ipc_free_security(&shp->shm_perm) -> ipc_free_security calls kfree(ipc_perms->security) This patch delays the freeing of the security structures after all RCU readers are done. Furthermore it aligns the security life cycle with that of the rest of IPC - freeing them based on the reference counter. For situations where we need not free security, the current behavior is kept. Linus states: "... the old behavior was suspect for another reason too: having the security blob go away from under a user sounds like it could cause various other problems anyway, so I think the old code was at least _prone_ to bugs even if it didn't have catastrophic behavior." I have tested this patch with IPC testcases from LTP on both my quad-core laptop and on a 64 core NUMA server. In both cases selinux is enabled, and tests pass for both voluntary and forced preemption models. While the mentioned races are theoretical (at least no one as reported them), I wanted to make sure that this new logic doesn't break anything we weren't aware of. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Davidlohr Bueso <davidlohr@hp.com> Acked-by: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1335 lines
32 KiB
C
1335 lines
32 KiB
C
/*
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* linux/ipc/shm.c
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* Copyright (C) 1992, 1993 Krishna Balasubramanian
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* Many improvements/fixes by Bruno Haible.
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* Replaced `struct shm_desc' by `struct vm_area_struct', July 1994.
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* Fixed the shm swap deallocation (shm_unuse()), August 1998 Andrea Arcangeli.
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*
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* /proc/sysvipc/shm support (c) 1999 Dragos Acostachioaie <dragos@iname.com>
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* BIGMEM support, Andrea Arcangeli <andrea@suse.de>
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* SMP thread shm, Jean-Luc Boyard <jean-luc.boyard@siemens.fr>
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* HIGHMEM support, Ingo Molnar <mingo@redhat.com>
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* Make shmmax, shmall, shmmni sysctl'able, Christoph Rohland <cr@sap.com>
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* Shared /dev/zero support, Kanoj Sarcar <kanoj@sgi.com>
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* Move the mm functionality over to mm/shmem.c, Christoph Rohland <cr@sap.com>
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*
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* support for audit of ipc object properties and permission changes
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* Dustin Kirkland <dustin.kirkland@us.ibm.com>
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*
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* namespaces support
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* OpenVZ, SWsoft Inc.
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* Pavel Emelianov <xemul@openvz.org>
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*
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* Better ipc lock (kern_ipc_perm.lock) handling
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* Davidlohr Bueso <davidlohr.bueso@hp.com>, June 2013.
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*/
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#include <linux/slab.h>
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#include <linux/mm.h>
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#include <linux/hugetlb.h>
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#include <linux/shm.h>
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#include <linux/init.h>
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#include <linux/file.h>
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#include <linux/mman.h>
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#include <linux/shmem_fs.h>
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#include <linux/security.h>
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#include <linux/syscalls.h>
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#include <linux/audit.h>
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#include <linux/capability.h>
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#include <linux/ptrace.h>
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#include <linux/seq_file.h>
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#include <linux/rwsem.h>
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#include <linux/nsproxy.h>
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#include <linux/mount.h>
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#include <linux/ipc_namespace.h>
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#include <asm/uaccess.h>
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#include "util.h"
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struct shm_file_data {
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int id;
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struct ipc_namespace *ns;
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struct file *file;
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const struct vm_operations_struct *vm_ops;
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};
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#define shm_file_data(file) (*((struct shm_file_data **)&(file)->private_data))
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static const struct file_operations shm_file_operations;
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static const struct vm_operations_struct shm_vm_ops;
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#define shm_ids(ns) ((ns)->ids[IPC_SHM_IDS])
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#define shm_unlock(shp) \
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ipc_unlock(&(shp)->shm_perm)
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static int newseg(struct ipc_namespace *, struct ipc_params *);
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static void shm_open(struct vm_area_struct *vma);
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static void shm_close(struct vm_area_struct *vma);
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static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp);
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#ifdef CONFIG_PROC_FS
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static int sysvipc_shm_proc_show(struct seq_file *s, void *it);
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#endif
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void shm_init_ns(struct ipc_namespace *ns)
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{
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ns->shm_ctlmax = SHMMAX;
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ns->shm_ctlall = SHMALL;
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ns->shm_ctlmni = SHMMNI;
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ns->shm_rmid_forced = 0;
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ns->shm_tot = 0;
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ipc_init_ids(&shm_ids(ns));
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}
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/*
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* Called with shm_ids.rwsem (writer) and the shp structure locked.
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* Only shm_ids.rwsem remains locked on exit.
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*/
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static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
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{
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struct shmid_kernel *shp;
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shp = container_of(ipcp, struct shmid_kernel, shm_perm);
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if (shp->shm_nattch){
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shp->shm_perm.mode |= SHM_DEST;
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/* Do not find it any more */
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shp->shm_perm.key = IPC_PRIVATE;
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shm_unlock(shp);
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} else
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shm_destroy(ns, shp);
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}
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#ifdef CONFIG_IPC_NS
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void shm_exit_ns(struct ipc_namespace *ns)
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{
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free_ipcs(ns, &shm_ids(ns), do_shm_rmid);
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idr_destroy(&ns->ids[IPC_SHM_IDS].ipcs_idr);
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}
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#endif
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static int __init ipc_ns_init(void)
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{
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shm_init_ns(&init_ipc_ns);
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return 0;
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}
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pure_initcall(ipc_ns_init);
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void __init shm_init (void)
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{
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ipc_init_proc_interface("sysvipc/shm",
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#if BITS_PER_LONG <= 32
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" key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n",
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#else
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" key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime rss swap\n",
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#endif
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IPC_SHM_IDS, sysvipc_shm_proc_show);
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}
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static inline struct shmid_kernel *shm_obtain_object(struct ipc_namespace *ns, int id)
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{
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struct kern_ipc_perm *ipcp = ipc_obtain_object(&shm_ids(ns), id);
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if (IS_ERR(ipcp))
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return ERR_CAST(ipcp);
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return container_of(ipcp, struct shmid_kernel, shm_perm);
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}
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static inline struct shmid_kernel *shm_obtain_object_check(struct ipc_namespace *ns, int id)
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{
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struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&shm_ids(ns), id);
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if (IS_ERR(ipcp))
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return ERR_CAST(ipcp);
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return container_of(ipcp, struct shmid_kernel, shm_perm);
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}
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/*
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* shm_lock_(check_) routines are called in the paths where the rwsem
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* is not necessarily held.
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*/
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static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id)
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{
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struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id);
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if (IS_ERR(ipcp))
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return (struct shmid_kernel *)ipcp;
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return container_of(ipcp, struct shmid_kernel, shm_perm);
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}
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static inline void shm_lock_by_ptr(struct shmid_kernel *ipcp)
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{
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rcu_read_lock();
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ipc_lock_object(&ipcp->shm_perm);
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}
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static void shm_rcu_free(struct rcu_head *head)
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{
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struct ipc_rcu *p = container_of(head, struct ipc_rcu, rcu);
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struct shmid_kernel *shp = ipc_rcu_to_struct(p);
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security_shm_free(shp);
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ipc_rcu_free(head);
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}
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static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
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{
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ipc_rmid(&shm_ids(ns), &s->shm_perm);
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}
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/* This is called by fork, once for every shm attach. */
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static void shm_open(struct vm_area_struct *vma)
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{
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struct file *file = vma->vm_file;
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struct shm_file_data *sfd = shm_file_data(file);
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struct shmid_kernel *shp;
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shp = shm_lock(sfd->ns, sfd->id);
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BUG_ON(IS_ERR(shp));
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shp->shm_atim = get_seconds();
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shp->shm_lprid = task_tgid_vnr(current);
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shp->shm_nattch++;
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shm_unlock(shp);
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}
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/*
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* shm_destroy - free the struct shmid_kernel
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*
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* @ns: namespace
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* @shp: struct to free
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*
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* It has to be called with shp and shm_ids.rwsem (writer) locked,
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* but returns with shp unlocked and freed.
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*/
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static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
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{
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ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
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shm_rmid(ns, shp);
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shm_unlock(shp);
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if (!is_file_hugepages(shp->shm_file))
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shmem_lock(shp->shm_file, 0, shp->mlock_user);
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else if (shp->mlock_user)
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user_shm_unlock(file_inode(shp->shm_file)->i_size,
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shp->mlock_user);
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fput (shp->shm_file);
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ipc_rcu_putref(shp, shm_rcu_free);
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}
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/*
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* shm_may_destroy - identifies whether shm segment should be destroyed now
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*
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* Returns true if and only if there are no active users of the segment and
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* one of the following is true:
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*
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* 1) shmctl(id, IPC_RMID, NULL) was called for this shp
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*
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* 2) sysctl kernel.shm_rmid_forced is set to 1.
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*/
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static bool shm_may_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
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{
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return (shp->shm_nattch == 0) &&
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(ns->shm_rmid_forced ||
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(shp->shm_perm.mode & SHM_DEST));
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}
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/*
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* remove the attach descriptor vma.
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* free memory for segment if it is marked destroyed.
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* The descriptor has already been removed from the current->mm->mmap list
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* and will later be kfree()d.
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*/
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static void shm_close(struct vm_area_struct *vma)
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{
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struct file * file = vma->vm_file;
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struct shm_file_data *sfd = shm_file_data(file);
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struct shmid_kernel *shp;
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struct ipc_namespace *ns = sfd->ns;
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down_write(&shm_ids(ns).rwsem);
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/* remove from the list of attaches of the shm segment */
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shp = shm_lock(ns, sfd->id);
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BUG_ON(IS_ERR(shp));
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shp->shm_lprid = task_tgid_vnr(current);
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shp->shm_dtim = get_seconds();
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shp->shm_nattch--;
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if (shm_may_destroy(ns, shp))
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shm_destroy(ns, shp);
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else
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shm_unlock(shp);
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up_write(&shm_ids(ns).rwsem);
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}
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/* Called with ns->shm_ids(ns).rwsem locked */
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static int shm_try_destroy_current(int id, void *p, void *data)
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{
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struct ipc_namespace *ns = data;
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struct kern_ipc_perm *ipcp = p;
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struct shmid_kernel *shp = container_of(ipcp, struct shmid_kernel, shm_perm);
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if (shp->shm_creator != current)
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return 0;
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/*
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* Mark it as orphaned to destroy the segment when
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* kernel.shm_rmid_forced is changed.
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* It is noop if the following shm_may_destroy() returns true.
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*/
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shp->shm_creator = NULL;
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/*
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* Don't even try to destroy it. If shm_rmid_forced=0 and IPC_RMID
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* is not set, it shouldn't be deleted here.
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*/
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if (!ns->shm_rmid_forced)
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return 0;
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if (shm_may_destroy(ns, shp)) {
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shm_lock_by_ptr(shp);
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shm_destroy(ns, shp);
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}
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return 0;
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}
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/* Called with ns->shm_ids(ns).rwsem locked */
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static int shm_try_destroy_orphaned(int id, void *p, void *data)
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{
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struct ipc_namespace *ns = data;
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struct kern_ipc_perm *ipcp = p;
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struct shmid_kernel *shp = container_of(ipcp, struct shmid_kernel, shm_perm);
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/*
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* We want to destroy segments without users and with already
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* exit'ed originating process.
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*
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* As shp->* are changed under rwsem, it's safe to skip shp locking.
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*/
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if (shp->shm_creator != NULL)
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return 0;
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if (shm_may_destroy(ns, shp)) {
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shm_lock_by_ptr(shp);
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shm_destroy(ns, shp);
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}
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return 0;
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}
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void shm_destroy_orphaned(struct ipc_namespace *ns)
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{
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down_write(&shm_ids(ns).rwsem);
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if (shm_ids(ns).in_use)
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idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_orphaned, ns);
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up_write(&shm_ids(ns).rwsem);
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}
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void exit_shm(struct task_struct *task)
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{
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struct ipc_namespace *ns = task->nsproxy->ipc_ns;
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if (shm_ids(ns).in_use == 0)
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return;
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/* Destroy all already created segments, but not mapped yet */
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down_write(&shm_ids(ns).rwsem);
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if (shm_ids(ns).in_use)
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idr_for_each(&shm_ids(ns).ipcs_idr, &shm_try_destroy_current, ns);
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up_write(&shm_ids(ns).rwsem);
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}
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static int shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
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{
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struct file *file = vma->vm_file;
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struct shm_file_data *sfd = shm_file_data(file);
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return sfd->vm_ops->fault(vma, vmf);
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}
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#ifdef CONFIG_NUMA
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static int shm_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
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{
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struct file *file = vma->vm_file;
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struct shm_file_data *sfd = shm_file_data(file);
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int err = 0;
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if (sfd->vm_ops->set_policy)
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err = sfd->vm_ops->set_policy(vma, new);
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return err;
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}
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static struct mempolicy *shm_get_policy(struct vm_area_struct *vma,
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unsigned long addr)
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{
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struct file *file = vma->vm_file;
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struct shm_file_data *sfd = shm_file_data(file);
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struct mempolicy *pol = NULL;
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if (sfd->vm_ops->get_policy)
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pol = sfd->vm_ops->get_policy(vma, addr);
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else if (vma->vm_policy)
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pol = vma->vm_policy;
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return pol;
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}
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#endif
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static int shm_mmap(struct file * file, struct vm_area_struct * vma)
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{
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struct shm_file_data *sfd = shm_file_data(file);
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int ret;
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ret = sfd->file->f_op->mmap(sfd->file, vma);
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if (ret != 0)
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return ret;
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sfd->vm_ops = vma->vm_ops;
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#ifdef CONFIG_MMU
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BUG_ON(!sfd->vm_ops->fault);
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#endif
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vma->vm_ops = &shm_vm_ops;
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shm_open(vma);
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return ret;
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}
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static int shm_release(struct inode *ino, struct file *file)
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{
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struct shm_file_data *sfd = shm_file_data(file);
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put_ipc_ns(sfd->ns);
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shm_file_data(file) = NULL;
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kfree(sfd);
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return 0;
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}
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static int shm_fsync(struct file *file, loff_t start, loff_t end, int datasync)
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{
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struct shm_file_data *sfd = shm_file_data(file);
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if (!sfd->file->f_op->fsync)
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return -EINVAL;
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return sfd->file->f_op->fsync(sfd->file, start, end, datasync);
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}
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static long shm_fallocate(struct file *file, int mode, loff_t offset,
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loff_t len)
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{
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struct shm_file_data *sfd = shm_file_data(file);
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if (!sfd->file->f_op->fallocate)
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return -EOPNOTSUPP;
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return sfd->file->f_op->fallocate(file, mode, offset, len);
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}
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static unsigned long shm_get_unmapped_area(struct file *file,
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unsigned long addr, unsigned long len, unsigned long pgoff,
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unsigned long flags)
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{
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struct shm_file_data *sfd = shm_file_data(file);
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return sfd->file->f_op->get_unmapped_area(sfd->file, addr, len,
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pgoff, flags);
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}
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static const struct file_operations shm_file_operations = {
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.mmap = shm_mmap,
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.fsync = shm_fsync,
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.release = shm_release,
|
|
#ifndef CONFIG_MMU
|
|
.get_unmapped_area = shm_get_unmapped_area,
|
|
#endif
|
|
.llseek = noop_llseek,
|
|
.fallocate = shm_fallocate,
|
|
};
|
|
|
|
static const struct file_operations shm_file_operations_huge = {
|
|
.mmap = shm_mmap,
|
|
.fsync = shm_fsync,
|
|
.release = shm_release,
|
|
.get_unmapped_area = shm_get_unmapped_area,
|
|
.llseek = noop_llseek,
|
|
.fallocate = shm_fallocate,
|
|
};
|
|
|
|
int is_file_shm_hugepages(struct file *file)
|
|
{
|
|
return file->f_op == &shm_file_operations_huge;
|
|
}
|
|
|
|
static const struct vm_operations_struct shm_vm_ops = {
|
|
.open = shm_open, /* callback for a new vm-area open */
|
|
.close = shm_close, /* callback for when the vm-area is released */
|
|
.fault = shm_fault,
|
|
#if defined(CONFIG_NUMA)
|
|
.set_policy = shm_set_policy,
|
|
.get_policy = shm_get_policy,
|
|
#endif
|
|
};
|
|
|
|
/**
|
|
* newseg - Create a new shared memory segment
|
|
* @ns: namespace
|
|
* @params: ptr to the structure that contains key, size and shmflg
|
|
*
|
|
* Called with shm_ids.rwsem held as a writer.
|
|
*/
|
|
|
|
static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
|
|
{
|
|
key_t key = params->key;
|
|
int shmflg = params->flg;
|
|
size_t size = params->u.size;
|
|
int error;
|
|
struct shmid_kernel *shp;
|
|
size_t numpages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
|
|
struct file * file;
|
|
char name[13];
|
|
int id;
|
|
vm_flags_t acctflag = 0;
|
|
|
|
if (size < SHMMIN || size > ns->shm_ctlmax)
|
|
return -EINVAL;
|
|
|
|
if (ns->shm_tot + numpages > ns->shm_ctlall)
|
|
return -ENOSPC;
|
|
|
|
shp = ipc_rcu_alloc(sizeof(*shp));
|
|
if (!shp)
|
|
return -ENOMEM;
|
|
|
|
shp->shm_perm.key = key;
|
|
shp->shm_perm.mode = (shmflg & S_IRWXUGO);
|
|
shp->mlock_user = NULL;
|
|
|
|
shp->shm_perm.security = NULL;
|
|
error = security_shm_alloc(shp);
|
|
if (error) {
|
|
ipc_rcu_putref(shp, ipc_rcu_free);
|
|
return error;
|
|
}
|
|
|
|
sprintf (name, "SYSV%08x", key);
|
|
if (shmflg & SHM_HUGETLB) {
|
|
struct hstate *hs;
|
|
size_t hugesize;
|
|
|
|
hs = hstate_sizelog((shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK);
|
|
if (!hs) {
|
|
error = -EINVAL;
|
|
goto no_file;
|
|
}
|
|
hugesize = ALIGN(size, huge_page_size(hs));
|
|
|
|
/* hugetlb_file_setup applies strict accounting */
|
|
if (shmflg & SHM_NORESERVE)
|
|
acctflag = VM_NORESERVE;
|
|
file = hugetlb_file_setup(name, hugesize, acctflag,
|
|
&shp->mlock_user, HUGETLB_SHMFS_INODE,
|
|
(shmflg >> SHM_HUGE_SHIFT) & SHM_HUGE_MASK);
|
|
} else {
|
|
/*
|
|
* Do not allow no accounting for OVERCOMMIT_NEVER, even
|
|
* if it's asked for.
|
|
*/
|
|
if ((shmflg & SHM_NORESERVE) &&
|
|
sysctl_overcommit_memory != OVERCOMMIT_NEVER)
|
|
acctflag = VM_NORESERVE;
|
|
file = shmem_file_setup(name, size, acctflag);
|
|
}
|
|
error = PTR_ERR(file);
|
|
if (IS_ERR(file))
|
|
goto no_file;
|
|
|
|
id = ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni);
|
|
if (id < 0) {
|
|
error = id;
|
|
goto no_id;
|
|
}
|
|
|
|
shp->shm_cprid = task_tgid_vnr(current);
|
|
shp->shm_lprid = 0;
|
|
shp->shm_atim = shp->shm_dtim = 0;
|
|
shp->shm_ctim = get_seconds();
|
|
shp->shm_segsz = size;
|
|
shp->shm_nattch = 0;
|
|
shp->shm_file = file;
|
|
shp->shm_creator = current;
|
|
|
|
/*
|
|
* shmid gets reported as "inode#" in /proc/pid/maps.
|
|
* proc-ps tools use this. Changing this will break them.
|
|
*/
|
|
file_inode(file)->i_ino = shp->shm_perm.id;
|
|
|
|
ns->shm_tot += numpages;
|
|
error = shp->shm_perm.id;
|
|
|
|
ipc_unlock_object(&shp->shm_perm);
|
|
rcu_read_unlock();
|
|
return error;
|
|
|
|
no_id:
|
|
if (is_file_hugepages(file) && shp->mlock_user)
|
|
user_shm_unlock(size, shp->mlock_user);
|
|
fput(file);
|
|
no_file:
|
|
ipc_rcu_putref(shp, shm_rcu_free);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Called with shm_ids.rwsem and ipcp locked.
|
|
*/
|
|
static inline int shm_security(struct kern_ipc_perm *ipcp, int shmflg)
|
|
{
|
|
struct shmid_kernel *shp;
|
|
|
|
shp = container_of(ipcp, struct shmid_kernel, shm_perm);
|
|
return security_shm_associate(shp, shmflg);
|
|
}
|
|
|
|
/*
|
|
* Called with shm_ids.rwsem and ipcp locked.
|
|
*/
|
|
static inline int shm_more_checks(struct kern_ipc_perm *ipcp,
|
|
struct ipc_params *params)
|
|
{
|
|
struct shmid_kernel *shp;
|
|
|
|
shp = container_of(ipcp, struct shmid_kernel, shm_perm);
|
|
if (shp->shm_segsz < params->u.size)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
SYSCALL_DEFINE3(shmget, key_t, key, size_t, size, int, shmflg)
|
|
{
|
|
struct ipc_namespace *ns;
|
|
struct ipc_ops shm_ops;
|
|
struct ipc_params shm_params;
|
|
|
|
ns = current->nsproxy->ipc_ns;
|
|
|
|
shm_ops.getnew = newseg;
|
|
shm_ops.associate = shm_security;
|
|
shm_ops.more_checks = shm_more_checks;
|
|
|
|
shm_params.key = key;
|
|
shm_params.flg = shmflg;
|
|
shm_params.u.size = size;
|
|
|
|
return ipcget(ns, &shm_ids(ns), &shm_ops, &shm_params);
|
|
}
|
|
|
|
static inline unsigned long copy_shmid_to_user(void __user *buf, struct shmid64_ds *in, int version)
|
|
{
|
|
switch(version) {
|
|
case IPC_64:
|
|
return copy_to_user(buf, in, sizeof(*in));
|
|
case IPC_OLD:
|
|
{
|
|
struct shmid_ds out;
|
|
|
|
memset(&out, 0, sizeof(out));
|
|
ipc64_perm_to_ipc_perm(&in->shm_perm, &out.shm_perm);
|
|
out.shm_segsz = in->shm_segsz;
|
|
out.shm_atime = in->shm_atime;
|
|
out.shm_dtime = in->shm_dtime;
|
|
out.shm_ctime = in->shm_ctime;
|
|
out.shm_cpid = in->shm_cpid;
|
|
out.shm_lpid = in->shm_lpid;
|
|
out.shm_nattch = in->shm_nattch;
|
|
|
|
return copy_to_user(buf, &out, sizeof(out));
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static inline unsigned long
|
|
copy_shmid_from_user(struct shmid64_ds *out, void __user *buf, int version)
|
|
{
|
|
switch(version) {
|
|
case IPC_64:
|
|
if (copy_from_user(out, buf, sizeof(*out)))
|
|
return -EFAULT;
|
|
return 0;
|
|
case IPC_OLD:
|
|
{
|
|
struct shmid_ds tbuf_old;
|
|
|
|
if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old)))
|
|
return -EFAULT;
|
|
|
|
out->shm_perm.uid = tbuf_old.shm_perm.uid;
|
|
out->shm_perm.gid = tbuf_old.shm_perm.gid;
|
|
out->shm_perm.mode = tbuf_old.shm_perm.mode;
|
|
|
|
return 0;
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminfo64 *in, int version)
|
|
{
|
|
switch(version) {
|
|
case IPC_64:
|
|
return copy_to_user(buf, in, sizeof(*in));
|
|
case IPC_OLD:
|
|
{
|
|
struct shminfo out;
|
|
|
|
if(in->shmmax > INT_MAX)
|
|
out.shmmax = INT_MAX;
|
|
else
|
|
out.shmmax = (int)in->shmmax;
|
|
|
|
out.shmmin = in->shmmin;
|
|
out.shmmni = in->shmmni;
|
|
out.shmseg = in->shmseg;
|
|
out.shmall = in->shmall;
|
|
|
|
return copy_to_user(buf, &out, sizeof(out));
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Calculate and add used RSS and swap pages of a shm.
|
|
* Called with shm_ids.rwsem held as a reader
|
|
*/
|
|
static void shm_add_rss_swap(struct shmid_kernel *shp,
|
|
unsigned long *rss_add, unsigned long *swp_add)
|
|
{
|
|
struct inode *inode;
|
|
|
|
inode = file_inode(shp->shm_file);
|
|
|
|
if (is_file_hugepages(shp->shm_file)) {
|
|
struct address_space *mapping = inode->i_mapping;
|
|
struct hstate *h = hstate_file(shp->shm_file);
|
|
*rss_add += pages_per_huge_page(h) * mapping->nrpages;
|
|
} else {
|
|
#ifdef CONFIG_SHMEM
|
|
struct shmem_inode_info *info = SHMEM_I(inode);
|
|
spin_lock(&info->lock);
|
|
*rss_add += inode->i_mapping->nrpages;
|
|
*swp_add += info->swapped;
|
|
spin_unlock(&info->lock);
|
|
#else
|
|
*rss_add += inode->i_mapping->nrpages;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Called with shm_ids.rwsem held as a reader
|
|
*/
|
|
static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
|
|
unsigned long *swp)
|
|
{
|
|
int next_id;
|
|
int total, in_use;
|
|
|
|
*rss = 0;
|
|
*swp = 0;
|
|
|
|
in_use = shm_ids(ns).in_use;
|
|
|
|
for (total = 0, next_id = 0; total < in_use; next_id++) {
|
|
struct kern_ipc_perm *ipc;
|
|
struct shmid_kernel *shp;
|
|
|
|
ipc = idr_find(&shm_ids(ns).ipcs_idr, next_id);
|
|
if (ipc == NULL)
|
|
continue;
|
|
shp = container_of(ipc, struct shmid_kernel, shm_perm);
|
|
|
|
shm_add_rss_swap(shp, rss, swp);
|
|
|
|
total++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* This function handles some shmctl commands which require the rwsem
|
|
* to be held in write mode.
|
|
* NOTE: no locks must be held, the rwsem is taken inside this function.
|
|
*/
|
|
static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
|
|
struct shmid_ds __user *buf, int version)
|
|
{
|
|
struct kern_ipc_perm *ipcp;
|
|
struct shmid64_ds shmid64;
|
|
struct shmid_kernel *shp;
|
|
int err;
|
|
|
|
if (cmd == IPC_SET) {
|
|
if (copy_shmid_from_user(&shmid64, buf, version))
|
|
return -EFAULT;
|
|
}
|
|
|
|
down_write(&shm_ids(ns).rwsem);
|
|
rcu_read_lock();
|
|
|
|
ipcp = ipcctl_pre_down_nolock(ns, &shm_ids(ns), shmid, cmd,
|
|
&shmid64.shm_perm, 0);
|
|
if (IS_ERR(ipcp)) {
|
|
err = PTR_ERR(ipcp);
|
|
goto out_unlock1;
|
|
}
|
|
|
|
shp = container_of(ipcp, struct shmid_kernel, shm_perm);
|
|
|
|
err = security_shm_shmctl(shp, cmd);
|
|
if (err)
|
|
goto out_unlock1;
|
|
|
|
switch (cmd) {
|
|
case IPC_RMID:
|
|
ipc_lock_object(&shp->shm_perm);
|
|
/* do_shm_rmid unlocks the ipc object and rcu */
|
|
do_shm_rmid(ns, ipcp);
|
|
goto out_up;
|
|
case IPC_SET:
|
|
ipc_lock_object(&shp->shm_perm);
|
|
err = ipc_update_perm(&shmid64.shm_perm, ipcp);
|
|
if (err)
|
|
goto out_unlock0;
|
|
shp->shm_ctim = get_seconds();
|
|
break;
|
|
default:
|
|
err = -EINVAL;
|
|
goto out_unlock1;
|
|
}
|
|
|
|
out_unlock0:
|
|
ipc_unlock_object(&shp->shm_perm);
|
|
out_unlock1:
|
|
rcu_read_unlock();
|
|
out_up:
|
|
up_write(&shm_ids(ns).rwsem);
|
|
return err;
|
|
}
|
|
|
|
static int shmctl_nolock(struct ipc_namespace *ns, int shmid,
|
|
int cmd, int version, void __user *buf)
|
|
{
|
|
int err;
|
|
struct shmid_kernel *shp;
|
|
|
|
/* preliminary security checks for *_INFO */
|
|
if (cmd == IPC_INFO || cmd == SHM_INFO) {
|
|
err = security_shm_shmctl(NULL, cmd);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
switch (cmd) {
|
|
case IPC_INFO:
|
|
{
|
|
struct shminfo64 shminfo;
|
|
|
|
memset(&shminfo, 0, sizeof(shminfo));
|
|
shminfo.shmmni = shminfo.shmseg = ns->shm_ctlmni;
|
|
shminfo.shmmax = ns->shm_ctlmax;
|
|
shminfo.shmall = ns->shm_ctlall;
|
|
|
|
shminfo.shmmin = SHMMIN;
|
|
if(copy_shminfo_to_user (buf, &shminfo, version))
|
|
return -EFAULT;
|
|
|
|
down_read(&shm_ids(ns).rwsem);
|
|
err = ipc_get_maxid(&shm_ids(ns));
|
|
up_read(&shm_ids(ns).rwsem);
|
|
|
|
if(err<0)
|
|
err = 0;
|
|
goto out;
|
|
}
|
|
case SHM_INFO:
|
|
{
|
|
struct shm_info shm_info;
|
|
|
|
memset(&shm_info, 0, sizeof(shm_info));
|
|
down_read(&shm_ids(ns).rwsem);
|
|
shm_info.used_ids = shm_ids(ns).in_use;
|
|
shm_get_stat (ns, &shm_info.shm_rss, &shm_info.shm_swp);
|
|
shm_info.shm_tot = ns->shm_tot;
|
|
shm_info.swap_attempts = 0;
|
|
shm_info.swap_successes = 0;
|
|
err = ipc_get_maxid(&shm_ids(ns));
|
|
up_read(&shm_ids(ns).rwsem);
|
|
if (copy_to_user(buf, &shm_info, sizeof(shm_info))) {
|
|
err = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
err = err < 0 ? 0 : err;
|
|
goto out;
|
|
}
|
|
case SHM_STAT:
|
|
case IPC_STAT:
|
|
{
|
|
struct shmid64_ds tbuf;
|
|
int result;
|
|
|
|
rcu_read_lock();
|
|
if (cmd == SHM_STAT) {
|
|
shp = shm_obtain_object(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out_unlock;
|
|
}
|
|
result = shp->shm_perm.id;
|
|
} else {
|
|
shp = shm_obtain_object_check(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out_unlock;
|
|
}
|
|
result = 0;
|
|
}
|
|
|
|
err = -EACCES;
|
|
if (ipcperms(ns, &shp->shm_perm, S_IRUGO))
|
|
goto out_unlock;
|
|
|
|
err = security_shm_shmctl(shp, cmd);
|
|
if (err)
|
|
goto out_unlock;
|
|
|
|
memset(&tbuf, 0, sizeof(tbuf));
|
|
kernel_to_ipc64_perm(&shp->shm_perm, &tbuf.shm_perm);
|
|
tbuf.shm_segsz = shp->shm_segsz;
|
|
tbuf.shm_atime = shp->shm_atim;
|
|
tbuf.shm_dtime = shp->shm_dtim;
|
|
tbuf.shm_ctime = shp->shm_ctim;
|
|
tbuf.shm_cpid = shp->shm_cprid;
|
|
tbuf.shm_lpid = shp->shm_lprid;
|
|
tbuf.shm_nattch = shp->shm_nattch;
|
|
rcu_read_unlock();
|
|
|
|
if (copy_shmid_to_user(buf, &tbuf, version))
|
|
err = -EFAULT;
|
|
else
|
|
err = result;
|
|
goto out;
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
out_unlock:
|
|
rcu_read_unlock();
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
|
|
{
|
|
struct shmid_kernel *shp;
|
|
int err, version;
|
|
struct ipc_namespace *ns;
|
|
|
|
if (cmd < 0 || shmid < 0)
|
|
return -EINVAL;
|
|
|
|
version = ipc_parse_version(&cmd);
|
|
ns = current->nsproxy->ipc_ns;
|
|
|
|
switch (cmd) {
|
|
case IPC_INFO:
|
|
case SHM_INFO:
|
|
case SHM_STAT:
|
|
case IPC_STAT:
|
|
return shmctl_nolock(ns, shmid, cmd, version, buf);
|
|
case IPC_RMID:
|
|
case IPC_SET:
|
|
return shmctl_down(ns, shmid, cmd, buf, version);
|
|
case SHM_LOCK:
|
|
case SHM_UNLOCK:
|
|
{
|
|
struct file *shm_file;
|
|
|
|
rcu_read_lock();
|
|
shp = shm_obtain_object_check(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out_unlock1;
|
|
}
|
|
|
|
audit_ipc_obj(&(shp->shm_perm));
|
|
err = security_shm_shmctl(shp, cmd);
|
|
if (err)
|
|
goto out_unlock1;
|
|
|
|
ipc_lock_object(&shp->shm_perm);
|
|
if (!ns_capable(ns->user_ns, CAP_IPC_LOCK)) {
|
|
kuid_t euid = current_euid();
|
|
err = -EPERM;
|
|
if (!uid_eq(euid, shp->shm_perm.uid) &&
|
|
!uid_eq(euid, shp->shm_perm.cuid))
|
|
goto out_unlock0;
|
|
if (cmd == SHM_LOCK && !rlimit(RLIMIT_MEMLOCK))
|
|
goto out_unlock0;
|
|
}
|
|
|
|
shm_file = shp->shm_file;
|
|
if (is_file_hugepages(shm_file))
|
|
goto out_unlock0;
|
|
|
|
if (cmd == SHM_LOCK) {
|
|
struct user_struct *user = current_user();
|
|
err = shmem_lock(shm_file, 1, user);
|
|
if (!err && !(shp->shm_perm.mode & SHM_LOCKED)) {
|
|
shp->shm_perm.mode |= SHM_LOCKED;
|
|
shp->mlock_user = user;
|
|
}
|
|
goto out_unlock0;
|
|
}
|
|
|
|
/* SHM_UNLOCK */
|
|
if (!(shp->shm_perm.mode & SHM_LOCKED))
|
|
goto out_unlock0;
|
|
shmem_lock(shm_file, 0, shp->mlock_user);
|
|
shp->shm_perm.mode &= ~SHM_LOCKED;
|
|
shp->mlock_user = NULL;
|
|
get_file(shm_file);
|
|
ipc_unlock_object(&shp->shm_perm);
|
|
rcu_read_unlock();
|
|
shmem_unlock_mapping(shm_file->f_mapping);
|
|
|
|
fput(shm_file);
|
|
return err;
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
out_unlock0:
|
|
ipc_unlock_object(&shp->shm_perm);
|
|
out_unlock1:
|
|
rcu_read_unlock();
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Fix shmaddr, allocate descriptor, map shm, add attach descriptor to lists.
|
|
*
|
|
* NOTE! Despite the name, this is NOT a direct system call entrypoint. The
|
|
* "raddr" thing points to kernel space, and there has to be a wrapper around
|
|
* this.
|
|
*/
|
|
long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr,
|
|
unsigned long shmlba)
|
|
{
|
|
struct shmid_kernel *shp;
|
|
unsigned long addr;
|
|
unsigned long size;
|
|
struct file * file;
|
|
int err;
|
|
unsigned long flags;
|
|
unsigned long prot;
|
|
int acc_mode;
|
|
struct ipc_namespace *ns;
|
|
struct shm_file_data *sfd;
|
|
struct path path;
|
|
fmode_t f_mode;
|
|
unsigned long populate = 0;
|
|
|
|
err = -EINVAL;
|
|
if (shmid < 0)
|
|
goto out;
|
|
else if ((addr = (ulong)shmaddr)) {
|
|
if (addr & (shmlba - 1)) {
|
|
if (shmflg & SHM_RND)
|
|
addr &= ~(shmlba - 1); /* round down */
|
|
else
|
|
#ifndef __ARCH_FORCE_SHMLBA
|
|
if (addr & ~PAGE_MASK)
|
|
#endif
|
|
goto out;
|
|
}
|
|
flags = MAP_SHARED | MAP_FIXED;
|
|
} else {
|
|
if ((shmflg & SHM_REMAP))
|
|
goto out;
|
|
|
|
flags = MAP_SHARED;
|
|
}
|
|
|
|
if (shmflg & SHM_RDONLY) {
|
|
prot = PROT_READ;
|
|
acc_mode = S_IRUGO;
|
|
f_mode = FMODE_READ;
|
|
} else {
|
|
prot = PROT_READ | PROT_WRITE;
|
|
acc_mode = S_IRUGO | S_IWUGO;
|
|
f_mode = FMODE_READ | FMODE_WRITE;
|
|
}
|
|
if (shmflg & SHM_EXEC) {
|
|
prot |= PROT_EXEC;
|
|
acc_mode |= S_IXUGO;
|
|
}
|
|
|
|
/*
|
|
* We cannot rely on the fs check since SYSV IPC does have an
|
|
* additional creator id...
|
|
*/
|
|
ns = current->nsproxy->ipc_ns;
|
|
rcu_read_lock();
|
|
shp = shm_obtain_object_check(ns, shmid);
|
|
if (IS_ERR(shp)) {
|
|
err = PTR_ERR(shp);
|
|
goto out_unlock;
|
|
}
|
|
|
|
err = -EACCES;
|
|
if (ipcperms(ns, &shp->shm_perm, acc_mode))
|
|
goto out_unlock;
|
|
|
|
err = security_shm_shmat(shp, shmaddr, shmflg);
|
|
if (err)
|
|
goto out_unlock;
|
|
|
|
ipc_lock_object(&shp->shm_perm);
|
|
path = shp->shm_file->f_path;
|
|
path_get(&path);
|
|
shp->shm_nattch++;
|
|
size = i_size_read(path.dentry->d_inode);
|
|
ipc_unlock_object(&shp->shm_perm);
|
|
rcu_read_unlock();
|
|
|
|
err = -ENOMEM;
|
|
sfd = kzalloc(sizeof(*sfd), GFP_KERNEL);
|
|
if (!sfd) {
|
|
path_put(&path);
|
|
goto out_nattch;
|
|
}
|
|
|
|
file = alloc_file(&path, f_mode,
|
|
is_file_hugepages(shp->shm_file) ?
|
|
&shm_file_operations_huge :
|
|
&shm_file_operations);
|
|
err = PTR_ERR(file);
|
|
if (IS_ERR(file)) {
|
|
kfree(sfd);
|
|
path_put(&path);
|
|
goto out_nattch;
|
|
}
|
|
|
|
file->private_data = sfd;
|
|
file->f_mapping = shp->shm_file->f_mapping;
|
|
sfd->id = shp->shm_perm.id;
|
|
sfd->ns = get_ipc_ns(ns);
|
|
sfd->file = shp->shm_file;
|
|
sfd->vm_ops = NULL;
|
|
|
|
err = security_mmap_file(file, prot, flags);
|
|
if (err)
|
|
goto out_fput;
|
|
|
|
down_write(¤t->mm->mmap_sem);
|
|
if (addr && !(shmflg & SHM_REMAP)) {
|
|
err = -EINVAL;
|
|
if (find_vma_intersection(current->mm, addr, addr + size))
|
|
goto invalid;
|
|
/*
|
|
* If shm segment goes below stack, make sure there is some
|
|
* space left for the stack to grow (at least 4 pages).
|
|
*/
|
|
if (addr < current->mm->start_stack &&
|
|
addr > current->mm->start_stack - size - PAGE_SIZE * 5)
|
|
goto invalid;
|
|
}
|
|
|
|
addr = do_mmap_pgoff(file, addr, size, prot, flags, 0, &populate);
|
|
*raddr = addr;
|
|
err = 0;
|
|
if (IS_ERR_VALUE(addr))
|
|
err = (long)addr;
|
|
invalid:
|
|
up_write(¤t->mm->mmap_sem);
|
|
if (populate)
|
|
mm_populate(addr, populate);
|
|
|
|
out_fput:
|
|
fput(file);
|
|
|
|
out_nattch:
|
|
down_write(&shm_ids(ns).rwsem);
|
|
shp = shm_lock(ns, shmid);
|
|
BUG_ON(IS_ERR(shp));
|
|
shp->shm_nattch--;
|
|
if (shm_may_destroy(ns, shp))
|
|
shm_destroy(ns, shp);
|
|
else
|
|
shm_unlock(shp);
|
|
up_write(&shm_ids(ns).rwsem);
|
|
return err;
|
|
|
|
out_unlock:
|
|
rcu_read_unlock();
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
SYSCALL_DEFINE3(shmat, int, shmid, char __user *, shmaddr, int, shmflg)
|
|
{
|
|
unsigned long ret;
|
|
long err;
|
|
|
|
err = do_shmat(shmid, shmaddr, shmflg, &ret, SHMLBA);
|
|
if (err)
|
|
return err;
|
|
force_successful_syscall_return();
|
|
return (long)ret;
|
|
}
|
|
|
|
/*
|
|
* detach and kill segment if marked destroyed.
|
|
* The work is done in shm_close.
|
|
*/
|
|
SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
|
|
{
|
|
struct mm_struct *mm = current->mm;
|
|
struct vm_area_struct *vma;
|
|
unsigned long addr = (unsigned long)shmaddr;
|
|
int retval = -EINVAL;
|
|
#ifdef CONFIG_MMU
|
|
loff_t size = 0;
|
|
struct vm_area_struct *next;
|
|
#endif
|
|
|
|
if (addr & ~PAGE_MASK)
|
|
return retval;
|
|
|
|
down_write(&mm->mmap_sem);
|
|
|
|
/*
|
|
* This function tries to be smart and unmap shm segments that
|
|
* were modified by partial mlock or munmap calls:
|
|
* - It first determines the size of the shm segment that should be
|
|
* unmapped: It searches for a vma that is backed by shm and that
|
|
* started at address shmaddr. It records it's size and then unmaps
|
|
* it.
|
|
* - Then it unmaps all shm vmas that started at shmaddr and that
|
|
* are within the initially determined size.
|
|
* Errors from do_munmap are ignored: the function only fails if
|
|
* it's called with invalid parameters or if it's called to unmap
|
|
* a part of a vma. Both calls in this function are for full vmas,
|
|
* the parameters are directly copied from the vma itself and always
|
|
* valid - therefore do_munmap cannot fail. (famous last words?)
|
|
*/
|
|
/*
|
|
* If it had been mremap()'d, the starting address would not
|
|
* match the usual checks anyway. So assume all vma's are
|
|
* above the starting address given.
|
|
*/
|
|
vma = find_vma(mm, addr);
|
|
|
|
#ifdef CONFIG_MMU
|
|
while (vma) {
|
|
next = vma->vm_next;
|
|
|
|
/*
|
|
* Check if the starting address would match, i.e. it's
|
|
* a fragment created by mprotect() and/or munmap(), or it
|
|
* otherwise it starts at this address with no hassles.
|
|
*/
|
|
if ((vma->vm_ops == &shm_vm_ops) &&
|
|
(vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) {
|
|
|
|
|
|
size = file_inode(vma->vm_file)->i_size;
|
|
do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
|
|
/*
|
|
* We discovered the size of the shm segment, so
|
|
* break out of here and fall through to the next
|
|
* loop that uses the size information to stop
|
|
* searching for matching vma's.
|
|
*/
|
|
retval = 0;
|
|
vma = next;
|
|
break;
|
|
}
|
|
vma = next;
|
|
}
|
|
|
|
/*
|
|
* We need look no further than the maximum address a fragment
|
|
* could possibly have landed at. Also cast things to loff_t to
|
|
* prevent overflows and make comparisons vs. equal-width types.
|
|
*/
|
|
size = PAGE_ALIGN(size);
|
|
while (vma && (loff_t)(vma->vm_end - addr) <= size) {
|
|
next = vma->vm_next;
|
|
|
|
/* finding a matching vma now does not alter retval */
|
|
if ((vma->vm_ops == &shm_vm_ops) &&
|
|
(vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff)
|
|
|
|
do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
|
|
vma = next;
|
|
}
|
|
|
|
#else /* CONFIG_MMU */
|
|
/* under NOMMU conditions, the exact address to be destroyed must be
|
|
* given */
|
|
if (vma && vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) {
|
|
do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
|
|
retval = 0;
|
|
}
|
|
|
|
#endif
|
|
|
|
up_write(&mm->mmap_sem);
|
|
return retval;
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static int sysvipc_shm_proc_show(struct seq_file *s, void *it)
|
|
{
|
|
struct user_namespace *user_ns = seq_user_ns(s);
|
|
struct shmid_kernel *shp = it;
|
|
unsigned long rss = 0, swp = 0;
|
|
|
|
shm_add_rss_swap(shp, &rss, &swp);
|
|
|
|
#if BITS_PER_LONG <= 32
|
|
#define SIZE_SPEC "%10lu"
|
|
#else
|
|
#define SIZE_SPEC "%21lu"
|
|
#endif
|
|
|
|
return seq_printf(s,
|
|
"%10d %10d %4o " SIZE_SPEC " %5u %5u "
|
|
"%5lu %5u %5u %5u %5u %10lu %10lu %10lu "
|
|
SIZE_SPEC " " SIZE_SPEC "\n",
|
|
shp->shm_perm.key,
|
|
shp->shm_perm.id,
|
|
shp->shm_perm.mode,
|
|
shp->shm_segsz,
|
|
shp->shm_cprid,
|
|
shp->shm_lprid,
|
|
shp->shm_nattch,
|
|
from_kuid_munged(user_ns, shp->shm_perm.uid),
|
|
from_kgid_munged(user_ns, shp->shm_perm.gid),
|
|
from_kuid_munged(user_ns, shp->shm_perm.cuid),
|
|
from_kgid_munged(user_ns, shp->shm_perm.cgid),
|
|
shp->shm_atim,
|
|
shp->shm_dtim,
|
|
shp->shm_ctim,
|
|
rss * PAGE_SIZE,
|
|
swp * PAGE_SIZE);
|
|
}
|
|
#endif
|