From 4e9823111bdc76127b17fc70dc57f584fd7dd34c Mon Sep 17 00:00:00 2001 From: Kirill Korotaev Date: Mon, 2 Oct 2006 02:18:22 -0700 Subject: [PATCH] [PATCH] IPC namespace - shm IPC namespace support for IPC shm code. Signed-off-by: Pavel Emelianiov Signed-off-by: Kirill Korotaev Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- ipc/shm.c | 254 ++++++++++++++++++++++++++++++++++++------------------ 1 file changed, 168 insertions(+), 86 deletions(-) diff --git a/ipc/shm.c b/ipc/shm.c index 940b0c9b13aa..bfbd317ec11c 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -15,6 +15,10 @@ * * support for audit of ipc object properties and permission changes * Dustin Kirkland + * + * namespaces support + * OpenVZ, SWsoft Inc. + * Pavel Emelianov */ #include @@ -32,6 +36,7 @@ #include #include #include +#include #include @@ -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(¤t->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;