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Diffstat (limited to 'ipc/shm.c')
-rw-r--r--ipc/shm.c347
1 files changed, 172 insertions, 175 deletions
diff --git a/ipc/shm.c b/ipc/shm.c
index 28a444861a8f..b4073c08d0e8 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -813,23 +813,17 @@ static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
* 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 shmid64_ds *shmid64)
{
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);
+ &shmid64->shm_perm, 0);
if (IS_ERR(ipcp)) {
err = PTR_ERR(ipcp);
goto out_unlock1;
@@ -849,7 +843,7 @@ static int shmctl_down(struct ipc_namespace *ns, int shmid, int cmd,
goto out_up;
case IPC_SET:
ipc_lock_object(&shp->shm_perm);
- err = ipc_update_perm(&shmid64.shm_perm, ipcp);
+ err = ipc_update_perm(&shmid64->shm_perm, ipcp);
if (err)
goto out_unlock0;
shp->shm_ctim = get_seconds();
@@ -868,212 +862,162 @@ out_up:
return err;
}
-static int shmctl_nolock(struct ipc_namespace *ns, int shmid,
- int cmd, int version, void __user *buf)
+static int shmctl_ipc_info(struct ipc_namespace *ns,
+ struct shminfo64 *shminfo)
{
- 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;
-
+ int err = security_shm_shmctl(NULL, IPC_INFO);
+ if (!err) {
+ 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;
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;
+ return err;
+}
- memset(&shm_info, 0, sizeof(shm_info));
+static int shmctl_shm_info(struct ipc_namespace *ns,
+ struct shm_info *shm_info)
+{
+ int err = security_shm_shmctl(NULL, SHM_INFO);
+ if (!err) {
+ 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;
+ 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;
+ if (err < 0)
+ err = 0;
}
- 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;
- }
+ return err;
+}
- err = -EACCES;
- if (ipcperms(ns, &shp->shm_perm, S_IRUGO))
- goto out_unlock;
+static int shmctl_stat(struct ipc_namespace *ns, int shmid,
+ int cmd, struct shmid64_ds *tbuf)
+{
+ struct shmid_kernel *shp;
+ int result;
+ int err;
- err = security_shm_shmctl(shp, cmd);
- if (err)
+ 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;
+ }
- 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();
+ err = -EACCES;
+ if (ipcperms(ns, &shp->shm_perm, S_IRUGO))
+ goto out_unlock;
- if (copy_shmid_to_user(buf, &tbuf, version))
- err = -EFAULT;
- else
- err = result;
- goto out;
- }
- default:
- return -EINVAL;
- }
+ 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();
+ return result;
out_unlock:
rcu_read_unlock();
-out:
return err;
}
-SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
+static int shmctl_do_lock(struct ipc_namespace *ns, int shmid, int cmd)
{
struct shmid_kernel *shp;
- int err, version;
- struct ipc_namespace *ns;
-
- if (cmd < 0 || shmid < 0)
- return -EINVAL;
+ struct file *shm_file;
+ int err;
- version = ipc_parse_version(&cmd);
- 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_unlock1;
+ }
- 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;
+ audit_ipc_obj(&(shp->shm_perm));
+ err = security_shm_shmctl(shp, cmd);
+ if (err)
+ goto out_unlock1;
- rcu_read_lock();
- shp = shm_obtain_object_check(ns, shmid);
- if (IS_ERR(shp)) {
- err = PTR_ERR(shp);
- goto out_unlock1;
- }
+ ipc_lock_object(&shp->shm_perm);
- audit_ipc_obj(&(shp->shm_perm));
- err = security_shm_shmctl(shp, cmd);
- if (err)
- goto out_unlock1;
+ /* check if shm_destroy() is tearing down shp */
+ if (!ipc_valid_object(&shp->shm_perm)) {
+ err = -EIDRM;
+ goto out_unlock0;
+ }
- ipc_lock_object(&shp->shm_perm);
+ if (!ns_capable(ns->user_ns, CAP_IPC_LOCK)) {
+ kuid_t euid = current_euid();
- /* check if shm_destroy() is tearing down shp */
- if (!ipc_valid_object(&shp->shm_perm)) {
- err = -EIDRM;
+ if (!uid_eq(euid, shp->shm_perm.uid) &&
+ !uid_eq(euid, shp->shm_perm.cuid)) {
+ err = -EPERM;
goto out_unlock0;
}
-
- if (!ns_capable(ns->user_ns, CAP_IPC_LOCK)) {
- kuid_t euid = current_euid();
-
- if (!uid_eq(euid, shp->shm_perm.uid) &&
- !uid_eq(euid, shp->shm_perm.cuid)) {
- err = -EPERM;
- goto out_unlock0;
- }
- if (cmd == SHM_LOCK && !rlimit(RLIMIT_MEMLOCK)) {
- err = -EPERM;
- goto out_unlock0;
- }
+ if (cmd == SHM_LOCK && !rlimit(RLIMIT_MEMLOCK)) {
+ err = -EPERM;
+ goto out_unlock0;
}
+ }
- shm_file = shp->shm_file;
- if (is_file_hugepages(shm_file))
- 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();
+ 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;
+ 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);
+ /* 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;
- }
+ fput(shm_file);
+ return err;
out_unlock0:
ipc_unlock_object(&shp->shm_perm);
@@ -1082,6 +1026,59 @@ out_unlock1:
return err;
}
+SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf)
+{
+ int err, version;
+ struct ipc_namespace *ns;
+ struct shmid64_ds tbuf;
+
+ if (cmd < 0 || shmid < 0)
+ return -EINVAL;
+
+ version = ipc_parse_version(&cmd);
+ ns = current->nsproxy->ipc_ns;
+
+ switch (cmd) {
+ case IPC_INFO: {
+ struct shminfo64 shminfo;
+ err = shmctl_ipc_info(ns, &shminfo);
+ if (err < 0)
+ return err;
+ if (copy_shminfo_to_user(buf, &shminfo, version))
+ err = -EFAULT;
+ return err;
+ }
+ case SHM_INFO: {
+ struct shm_info shm_info;
+ err = shmctl_shm_info(ns, &shm_info);
+ if (err < 0)
+ return err;
+ if (copy_to_user(buf, &shm_info, sizeof(shm_info)))
+ err = -EFAULT;
+ return err;
+ }
+ case SHM_STAT:
+ case IPC_STAT: {
+ err = shmctl_stat(ns, shmid, cmd, &tbuf);
+ if (err < 0)
+ return err;
+ if (copy_shmid_to_user(buf, &tbuf, version))
+ err = -EFAULT;
+ return err;
+ }
+ case IPC_SET:
+ if (copy_shmid_from_user(&tbuf, buf, version))
+ return -EFAULT;
+ case IPC_RMID:
+ return shmctl_down(ns, shmid, cmd, &tbuf);
+ case SHM_LOCK:
+ case SHM_UNLOCK:
+ return shmctl_do_lock(ns, shmid, cmd);
+ default:
+ return -EINVAL;
+ }
+}
+
/*
* Fix shmaddr, allocate descriptor, map shm, add attach descriptor to lists.
*