[PATCH] IPC namespace - shm

IPC namespace support for IPC shm code.

Signed-off-by: Pavel Emelianiov <xemul@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Kirill Korotaev 2006-10-02 02:18:22 -07:00 committed by Linus Torvalds
parent e38935341a
commit 4e9823111b

254
ipc/shm.c
View file

@ -15,6 +15,10 @@
*
* support for audit of ipc object properties and permission changes
* Dustin Kirkland <dustin.kirkland@us.ibm.com>
*
* namespaces support
* OpenVZ, SWsoft Inc.
* Pavel Emelianov <xemul@openvz.org>
*/
#include <linux/slab.h>
@ -32,6 +36,7 @@
#include <linux/ptrace.h>
#include <linux/seq_file.h>
#include <linux/mutex.h>
#include <linux/nsproxy.h>
#include <asm/uaccess.h>
@ -40,59 +45,115 @@
static struct file_operations shm_file_operations;
static struct vm_operations_struct shm_vm_ops;
static struct ipc_ids shm_ids;
static struct ipc_ids init_shm_ids;
#define shm_lock(id) ((struct shmid_kernel*)ipc_lock(&shm_ids,id))
#define shm_unlock(shp) ipc_unlock(&(shp)->shm_perm)
#define shm_get(id) ((struct shmid_kernel*)ipc_get(&shm_ids,id))
#define shm_buildid(id, seq) \
ipc_buildid(&shm_ids, id, seq)
#define shm_ids(ns) (*((ns)->ids[IPC_SHM_IDS]))
static int newseg (key_t key, int shmflg, size_t size);
#define shm_lock(ns, id) \
((struct shmid_kernel*)ipc_lock(&shm_ids(ns),id))
#define shm_unlock(shp) \
ipc_unlock(&(shp)->shm_perm)
#define shm_get(ns, id) \
((struct shmid_kernel*)ipc_get(&shm_ids(ns),id))
#define shm_buildid(ns, id, seq) \
ipc_buildid(&shm_ids(ns), id, seq)
static int newseg (struct ipc_namespace *ns, key_t key,
int shmflg, size_t size);
static void shm_open (struct vm_area_struct *shmd);
static void shm_close (struct vm_area_struct *shmd);
static void shm_destroy (struct ipc_namespace *ns, struct shmid_kernel *shp);
#ifdef CONFIG_PROC_FS
static int sysvipc_shm_proc_show(struct seq_file *s, void *it);
#endif
size_t shm_ctlmax = SHMMAX;
size_t shm_ctlall = SHMALL;
int shm_ctlmni = SHMMNI;
static void __ipc_init __shm_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
{
ns->ids[IPC_SHM_IDS] = ids;
ns->shm_ctlmax = SHMMAX;
ns->shm_ctlall = SHMALL;
ns->shm_ctlmni = SHMMNI;
ns->shm_tot = 0;
ipc_init_ids(ids, 1);
}
static int shm_tot; /* total number of shared memory pages */
static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
{
if (shp->shm_nattch){
shp->shm_perm.mode |= SHM_DEST;
/* Do not find it any more */
shp->shm_perm.key = IPC_PRIVATE;
shm_unlock(shp);
} else
shm_destroy(ns, shp);
}
#ifdef CONFIG_IPC_NS
int shm_init_ns(struct ipc_namespace *ns)
{
struct ipc_ids *ids;
ids = kmalloc(sizeof(struct ipc_ids), GFP_KERNEL);
if (ids == NULL)
return -ENOMEM;
__shm_init_ns(ns, ids);
return 0;
}
void shm_exit_ns(struct ipc_namespace *ns)
{
int i;
struct shmid_kernel *shp;
mutex_lock(&shm_ids(ns).mutex);
for (i = 0; i <= shm_ids(ns).max_id; i++) {
shp = shm_lock(ns, i);
if (shp == NULL)
continue;
do_shm_rmid(ns, shp);
}
mutex_unlock(&shm_ids(ns).mutex);
kfree(ns->ids[IPC_SHM_IDS]);
ns->ids[IPC_SHM_IDS] = NULL;
}
#endif
void __init shm_init (void)
{
ipc_init_ids(&shm_ids, 1);
__shm_init_ns(&init_ipc_ns, &init_shm_ids);
ipc_init_proc_interface("sysvipc/shm",
" key shmid perms size cpid lpid nattch uid gid cuid cgid atime dtime ctime\n",
&shm_ids,
sysvipc_shm_proc_show);
IPC_SHM_IDS, sysvipc_shm_proc_show);
}
static inline int shm_checkid(struct shmid_kernel *s, int id)
static inline int shm_checkid(struct ipc_namespace *ns,
struct shmid_kernel *s, int id)
{
if (ipc_checkid(&shm_ids,&s->shm_perm,id))
if (ipc_checkid(&shm_ids(ns), &s->shm_perm, id))
return -EIDRM;
return 0;
}
static inline struct shmid_kernel *shm_rmid(int id)
static inline struct shmid_kernel *shm_rmid(struct ipc_namespace *ns, int id)
{
return (struct shmid_kernel *)ipc_rmid(&shm_ids,id);
return (struct shmid_kernel *)ipc_rmid(&shm_ids(ns), id);
}
static inline int shm_addid(struct shmid_kernel *shp)
static inline int shm_addid(struct ipc_namespace *ns, struct shmid_kernel *shp)
{
return ipc_addid(&shm_ids, &shp->shm_perm, shm_ctlmni);
return ipc_addid(&shm_ids(ns), &shp->shm_perm, ns->shm_ctlmni);
}
static inline void shm_inc (int id) {
static inline void shm_inc(struct ipc_namespace *ns, int id)
{
struct shmid_kernel *shp;
shp = shm_lock(id);
shp = shm_lock(ns, id);
BUG_ON(!shp);
shp->shm_atim = get_seconds();
shp->shm_lprid = current->tgid;
@ -100,10 +161,13 @@ static inline void shm_inc (int id) {
shm_unlock(shp);
}
#define shm_file_ns(file) (*((struct ipc_namespace **)&(file)->private_data))
/* This is called by fork, once for every shm attach. */
static void shm_open (struct vm_area_struct *shmd)
static void shm_open(struct vm_area_struct *shmd)
{
shm_inc (shmd->vm_file->f_dentry->d_inode->i_ino);
shm_inc(shm_file_ns(shmd->vm_file),
shmd->vm_file->f_dentry->d_inode->i_ino);
}
/*
@ -114,10 +178,10 @@ static void shm_open (struct vm_area_struct *shmd)
* It has to be called with shp and shm_ids.mutex locked,
* but returns with shp unlocked and freed.
*/
static void shm_destroy (struct shmid_kernel *shp)
static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
{
shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
shm_rmid (shp->id);
ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
shm_rmid(ns, shp->id);
shm_unlock(shp);
if (!is_file_hugepages(shp->shm_file))
shmem_lock(shp->shm_file, 0, shp->mlock_user);
@ -140,20 +204,23 @@ static void shm_close (struct vm_area_struct *shmd)
struct file * file = shmd->vm_file;
int id = file->f_dentry->d_inode->i_ino;
struct shmid_kernel *shp;
struct ipc_namespace *ns;
mutex_lock(&shm_ids.mutex);
ns = shm_file_ns(file);
mutex_lock(&shm_ids(ns).mutex);
/* remove from the list of attaches of the shm segment */
shp = shm_lock(id);
shp = shm_lock(ns, id);
BUG_ON(!shp);
shp->shm_lprid = current->tgid;
shp->shm_dtim = get_seconds();
shp->shm_nattch--;
if(shp->shm_nattch == 0 &&
shp->shm_perm.mode & SHM_DEST)
shm_destroy (shp);
shm_destroy(ns, shp);
else
shm_unlock(shp);
mutex_unlock(&shm_ids.mutex);
mutex_unlock(&shm_ids(ns).mutex);
}
static int shm_mmap(struct file * file, struct vm_area_struct * vma)
@ -165,14 +232,25 @@ static int shm_mmap(struct file * file, struct vm_area_struct * vma)
vma->vm_ops = &shm_vm_ops;
if (!(vma->vm_flags & VM_WRITE))
vma->vm_flags &= ~VM_MAYWRITE;
shm_inc(file->f_dentry->d_inode->i_ino);
shm_inc(shm_file_ns(file), file->f_dentry->d_inode->i_ino);
}
return ret;
}
static int shm_release(struct inode *ino, struct file *file)
{
struct ipc_namespace *ns;
ns = shm_file_ns(file);
put_ipc_ns(ns);
shm_file_ns(file) = NULL;
return 0;
}
static struct file_operations shm_file_operations = {
.mmap = shm_mmap,
.mmap = shm_mmap,
.release = shm_release,
#ifndef CONFIG_MMU
.get_unmapped_area = shmem_get_unmapped_area,
#endif
@ -188,7 +266,7 @@ static struct vm_operations_struct shm_vm_ops = {
#endif
};
static int newseg (key_t key, int shmflg, size_t size)
static int newseg (struct ipc_namespace *ns, key_t key, int shmflg, size_t size)
{
int error;
struct shmid_kernel *shp;
@ -197,10 +275,10 @@ static int newseg (key_t key, int shmflg, size_t size)
char name[13];
int id;
if (size < SHMMIN || size > shm_ctlmax)
if (size < SHMMIN || size > ns->shm_ctlmax)
return -EINVAL;
if (shm_tot + numpages >= shm_ctlall)
if (ns->shm_tot + numpages >= ns->shm_ctlall)
return -ENOSPC;
shp = ipc_rcu_alloc(sizeof(*shp));
@ -239,7 +317,7 @@ static int newseg (key_t key, int shmflg, size_t size)
goto no_file;
error = -ENOSPC;
id = shm_addid(shp);
id = shm_addid(ns, shp);
if(id == -1)
goto no_id;
@ -249,15 +327,17 @@ static int newseg (key_t key, int shmflg, size_t size)
shp->shm_ctim = get_seconds();
shp->shm_segsz = size;
shp->shm_nattch = 0;
shp->id = shm_buildid(id,shp->shm_perm.seq);
shp->id = shm_buildid(ns, id, shp->shm_perm.seq);
shp->shm_file = file;
file->f_dentry->d_inode->i_ino = shp->id;
shm_file_ns(file) = get_ipc_ns(ns);
/* Hugetlb ops would have already been assigned. */
if (!(shmflg & SHM_HUGETLB))
file->f_op = &shm_file_operations;
shm_tot += numpages;
ns->shm_tot += numpages;
shm_unlock(shp);
return shp->id;
@ -273,33 +353,36 @@ asmlinkage long sys_shmget (key_t key, size_t size, int shmflg)
{
struct shmid_kernel *shp;
int err, id = 0;
struct ipc_namespace *ns;
mutex_lock(&shm_ids.mutex);
ns = current->nsproxy->ipc_ns;
mutex_lock(&shm_ids(ns).mutex);
if (key == IPC_PRIVATE) {
err = newseg(key, shmflg, size);
} else if ((id = ipc_findkey(&shm_ids, key)) == -1) {
err = newseg(ns, key, shmflg, size);
} else if ((id = ipc_findkey(&shm_ids(ns), key)) == -1) {
if (!(shmflg & IPC_CREAT))
err = -ENOENT;
else
err = newseg(key, shmflg, size);
err = newseg(ns, key, shmflg, size);
} else if ((shmflg & IPC_CREAT) && (shmflg & IPC_EXCL)) {
err = -EEXIST;
} else {
shp = shm_lock(id);
shp = shm_lock(ns, id);
BUG_ON(shp==NULL);
if (shp->shm_segsz < size)
err = -EINVAL;
else if (ipcperms(&shp->shm_perm, shmflg))
err = -EACCES;
else {
int shmid = shm_buildid(id, shp->shm_perm.seq);
int shmid = shm_buildid(ns, id, shp->shm_perm.seq);
err = security_shm_associate(shp, shmflg);
if (!err)
err = shmid;
}
shm_unlock(shp);
}
mutex_unlock(&shm_ids.mutex);
mutex_unlock(&shm_ids(ns).mutex);
return err;
}
@ -395,18 +478,19 @@ static inline unsigned long copy_shminfo_to_user(void __user *buf, struct shminf
}
}
static void shm_get_stat(unsigned long *rss, unsigned long *swp)
static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
unsigned long *swp)
{
int i;
*rss = 0;
*swp = 0;
for (i = 0; i <= shm_ids.max_id; i++) {
for (i = 0; i <= shm_ids(ns).max_id; i++) {
struct shmid_kernel *shp;
struct inode *inode;
shp = shm_get(i);
shp = shm_get(ns, i);
if(!shp)
continue;
@ -430,6 +514,7 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
struct shm_setbuf setbuf;
struct shmid_kernel *shp;
int err, version;
struct ipc_namespace *ns;
if (cmd < 0 || shmid < 0) {
err = -EINVAL;
@ -437,6 +522,7 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
}
version = ipc_parse_version(&cmd);
ns = current->nsproxy->ipc_ns;
switch (cmd) { /* replace with proc interface ? */
case IPC_INFO:
@ -448,15 +534,15 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
return err;
memset(&shminfo,0,sizeof(shminfo));
shminfo.shmmni = shminfo.shmseg = shm_ctlmni;
shminfo.shmmax = shm_ctlmax;
shminfo.shmall = shm_ctlall;
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;
/* reading a integer is always atomic */
err= shm_ids.max_id;
err= shm_ids(ns).max_id;
if(err<0)
err = 0;
goto out;
@ -470,14 +556,14 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
return err;
memset(&shm_info,0,sizeof(shm_info));
mutex_lock(&shm_ids.mutex);
shm_info.used_ids = shm_ids.in_use;
shm_get_stat (&shm_info.shm_rss, &shm_info.shm_swp);
shm_info.shm_tot = shm_tot;
mutex_lock(&shm_ids(ns).mutex);
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 = shm_ids.max_id;
mutex_unlock(&shm_ids.mutex);
err = shm_ids(ns).max_id;
mutex_unlock(&shm_ids(ns).mutex);
if(copy_to_user (buf, &shm_info, sizeof(shm_info))) {
err = -EFAULT;
goto out;
@ -492,17 +578,17 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
struct shmid64_ds tbuf;
int result;
memset(&tbuf, 0, sizeof(tbuf));
shp = shm_lock(shmid);
shp = shm_lock(ns, shmid);
if(shp==NULL) {
err = -EINVAL;
goto out;
} else if(cmd==SHM_STAT) {
err = -EINVAL;
if (shmid > shm_ids.max_id)
if (shmid > shm_ids(ns).max_id)
goto out_unlock;
result = shm_buildid(shmid, shp->shm_perm.seq);
result = shm_buildid(ns, shmid, shp->shm_perm.seq);
} else {
err = shm_checkid(shp,shmid);
err = shm_checkid(ns, shp,shmid);
if(err)
goto out_unlock;
result = 0;
@ -534,12 +620,12 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
case SHM_LOCK:
case SHM_UNLOCK:
{
shp = shm_lock(shmid);
shp = shm_lock(ns, shmid);
if(shp==NULL) {
err = -EINVAL;
goto out;
}
err = shm_checkid(shp,shmid);
err = shm_checkid(ns, shp,shmid);
if(err)
goto out_unlock;
@ -590,12 +676,12 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
* Instead we set a destroyed flag, and then blow
* the name away when the usage hits zero.
*/
mutex_lock(&shm_ids.mutex);
shp = shm_lock(shmid);
mutex_lock(&shm_ids(ns).mutex);
shp = shm_lock(ns, shmid);
err = -EINVAL;
if (shp == NULL)
goto out_up;
err = shm_checkid(shp, shmid);
err = shm_checkid(ns, shp, shmid);
if(err)
goto out_unlock_up;
@ -614,14 +700,8 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
if (err)
goto out_unlock_up;
if (shp->shm_nattch){
shp->shm_perm.mode |= SHM_DEST;
/* Do not find it any more */
shp->shm_perm.key = IPC_PRIVATE;
shm_unlock(shp);
} else
shm_destroy (shp);
mutex_unlock(&shm_ids.mutex);
do_shm_rmid(ns, shp);
mutex_unlock(&shm_ids(ns).mutex);
goto out;
}
@ -631,12 +711,12 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
err = -EFAULT;
goto out;
}
mutex_lock(&shm_ids.mutex);
shp = shm_lock(shmid);
mutex_lock(&shm_ids(ns).mutex);
shp = shm_lock(ns, shmid);
err=-EINVAL;
if(shp==NULL)
goto out_up;
err = shm_checkid(shp,shmid);
err = shm_checkid(ns, shp,shmid);
if(err)
goto out_unlock_up;
err = audit_ipc_obj(&(shp->shm_perm));
@ -673,7 +753,7 @@ asmlinkage long sys_shmctl (int shmid, int cmd, struct shmid_ds __user *buf)
out_unlock_up:
shm_unlock(shp);
out_up:
mutex_unlock(&shm_ids.mutex);
mutex_unlock(&shm_ids(ns).mutex);
goto out;
out_unlock:
shm_unlock(shp);
@ -699,6 +779,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
unsigned long prot;
int acc_mode;
void *user_addr;
struct ipc_namespace *ns;
if (shmid < 0) {
err = -EINVAL;
@ -737,12 +818,13 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
* We cannot rely on the fs check since SYSV IPC does have an
* additional creator id...
*/
shp = shm_lock(shmid);
ns = current->nsproxy->ipc_ns;
shp = shm_lock(ns, shmid);
if(shp == NULL) {
err = -EINVAL;
goto out;
}
err = shm_checkid(shp,shmid);
err = shm_checkid(ns, shp,shmid);
if (err) {
shm_unlock(shp);
goto out;
@ -783,16 +865,16 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
invalid:
up_write(&current->mm->mmap_sem);
mutex_lock(&shm_ids.mutex);
shp = shm_lock(shmid);
mutex_lock(&shm_ids(ns).mutex);
shp = shm_lock(ns, shmid);
BUG_ON(!shp);
shp->shm_nattch--;
if(shp->shm_nattch == 0 &&
shp->shm_perm.mode & SHM_DEST)
shm_destroy (shp);
shm_destroy(ns, shp);
else
shm_unlock(shp);
mutex_unlock(&shm_ids.mutex);
mutex_unlock(&shm_ids(ns).mutex);
*raddr = (unsigned long) user_addr;
err = 0;