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Diffstat (limited to 'fs')
-rw-r--r--fs/devpts/inode.c71
-rw-r--r--fs/mount.h1
-rw-r--r--fs/namespace.c22
-rw-r--r--fs/proc/proc_sysctl.c14
4 files changed, 55 insertions, 53 deletions
diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index d116453b0276..154cc45c19e8 100644
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -272,13 +272,8 @@ static int mknod_ptmx(struct super_block *sb)
struct dentry *root = sb->s_root;
struct pts_fs_info *fsi = DEVPTS_SB(sb);
struct pts_mount_opts *opts = &fsi->mount_opts;
- kuid_t root_uid;
- kgid_t root_gid;
-
- root_uid = make_kuid(current_user_ns(), 0);
- root_gid = make_kgid(current_user_ns(), 0);
- if (!uid_valid(root_uid) || !gid_valid(root_gid))
- return -EINVAL;
+ kuid_t ptmx_uid = current_fsuid();
+ kgid_t ptmx_gid = current_fsgid();
inode_lock(d_inode(root));
@@ -309,8 +304,8 @@ static int mknod_ptmx(struct super_block *sb)
mode = S_IFCHR|opts->ptmxmode;
init_special_inode(inode, mode, MKDEV(TTYAUX_MAJOR, 2));
- inode->i_uid = root_uid;
- inode->i_gid = root_gid;
+ inode->i_uid = ptmx_uid;
+ inode->i_gid = ptmx_gid;
d_add(dentry, inode);
@@ -336,7 +331,6 @@ static int devpts_remount(struct super_block *sb, int *flags, char *data)
struct pts_fs_info *fsi = DEVPTS_SB(sb);
struct pts_mount_opts *opts = &fsi->mount_opts;
- sync_filesystem(sb);
err = parse_mount_options(data, PARSE_REMOUNT, opts);
/*
@@ -395,6 +389,7 @@ static int
devpts_fill_super(struct super_block *s, void *data, int silent)
{
struct inode *inode;
+ int error;
s->s_iflags &= ~SB_I_NODEV;
s->s_blocksize = 1024;
@@ -403,10 +398,16 @@ devpts_fill_super(struct super_block *s, void *data, int silent)
s->s_op = &devpts_sops;
s->s_time_gran = 1;
+ error = -ENOMEM;
s->s_fs_info = new_pts_fs_info(s);
if (!s->s_fs_info)
goto fail;
+ error = parse_mount_options(data, PARSE_MOUNT, &DEVPTS_SB(s)->mount_opts);
+ if (error)
+ goto fail;
+
+ error = -ENOMEM;
inode = new_inode(s);
if (!inode)
goto fail;
@@ -418,13 +419,21 @@ devpts_fill_super(struct super_block *s, void *data, int silent)
set_nlink(inode, 2);
s->s_root = d_make_root(inode);
- if (s->s_root)
- return 0;
+ if (!s->s_root) {
+ pr_err("get root dentry failed\n");
+ goto fail;
+ }
- pr_err("get root dentry failed\n");
+ error = mknod_ptmx(s);
+ if (error)
+ goto fail_dput;
+ return 0;
+fail_dput:
+ dput(s->s_root);
+ s->s_root = NULL;
fail:
- return -ENOMEM;
+ return error;
}
/*
@@ -436,43 +445,15 @@ fail:
static struct dentry *devpts_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
- int error;
- struct pts_mount_opts opts;
- struct super_block *s;
-
- error = parse_mount_options(data, PARSE_MOUNT, &opts);
- if (error)
- return ERR_PTR(error);
-
- s = sget(fs_type, NULL, set_anon_super, flags, NULL);
- if (IS_ERR(s))
- return ERR_CAST(s);
-
- if (!s->s_root) {
- error = devpts_fill_super(s, data, flags & MS_SILENT ? 1 : 0);
- if (error)
- goto out_undo_sget;
- s->s_flags |= MS_ACTIVE;
- }
-
- memcpy(&(DEVPTS_SB(s))->mount_opts, &opts, sizeof(opts));
-
- error = mknod_ptmx(s);
- if (error)
- goto out_undo_sget;
-
- return dget(s->s_root);
-
-out_undo_sget:
- deactivate_locked_super(s);
- return ERR_PTR(error);
+ return mount_nodev(fs_type, flags, data, devpts_fill_super);
}
static void devpts_kill_sb(struct super_block *sb)
{
struct pts_fs_info *fsi = DEVPTS_SB(sb);
- ida_destroy(&fsi->allocated_ptys);
+ if (fsi)
+ ida_destroy(&fsi->allocated_ptys);
kfree(fsi);
kill_litter_super(sb);
}
diff --git a/fs/mount.h b/fs/mount.h
index 14db05d424f7..e037981d8351 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -10,6 +10,7 @@ struct mnt_namespace {
struct mount * root;
struct list_head list;
struct user_namespace *user_ns;
+ struct ucounts *ucounts;
u64 seq; /* Sequence number to prevent loops */
wait_queue_head_t poll;
u64 event;
diff --git a/fs/namespace.c b/fs/namespace.c
index fea56f310547..8a0e90eb81d3 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2719,9 +2719,20 @@ dput_out:
return retval;
}
+static struct ucounts *inc_mnt_namespaces(struct user_namespace *ns)
+{
+ return inc_ucount(ns, current_euid(), UCOUNT_MNT_NAMESPACES);
+}
+
+static void dec_mnt_namespaces(struct ucounts *ucounts)
+{
+ dec_ucount(ucounts, UCOUNT_MNT_NAMESPACES);
+}
+
static void free_mnt_ns(struct mnt_namespace *ns)
{
ns_free_inum(&ns->ns);
+ dec_mnt_namespaces(ns->ucounts);
put_user_ns(ns->user_ns);
kfree(ns);
}
@@ -2738,14 +2749,22 @@ static atomic64_t mnt_ns_seq = ATOMIC64_INIT(1);
static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns)
{
struct mnt_namespace *new_ns;
+ struct ucounts *ucounts;
int ret;
+ ucounts = inc_mnt_namespaces(user_ns);
+ if (!ucounts)
+ return ERR_PTR(-ENOSPC);
+
new_ns = kmalloc(sizeof(struct mnt_namespace), GFP_KERNEL);
- if (!new_ns)
+ if (!new_ns) {
+ dec_mnt_namespaces(ucounts);
return ERR_PTR(-ENOMEM);
+ }
ret = ns_alloc_inum(&new_ns->ns);
if (ret) {
kfree(new_ns);
+ dec_mnt_namespaces(ucounts);
return ERR_PTR(ret);
}
new_ns->ns.ops = &mntns_operations;
@@ -2756,6 +2775,7 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns)
init_waitqueue_head(&new_ns->poll);
new_ns->event = 0;
new_ns->user_ns = get_user_ns(user_ns);
+ new_ns->ucounts = ucounts;
return new_ns;
}
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 1b93650dda2f..a80acdfbe180 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -72,7 +72,7 @@ static DEFINE_SPINLOCK(sysctl_lock);
static void drop_sysctl_table(struct ctl_table_header *header);
static int sysctl_follow_link(struct ctl_table_header **phead,
- struct ctl_table **pentry, struct nsproxy *namespaces);
+ struct ctl_table **pentry);
static int insert_links(struct ctl_table_header *head);
static void put_links(struct ctl_table_header *header);
@@ -319,11 +319,11 @@ static void sysctl_head_finish(struct ctl_table_header *head)
}
static struct ctl_table_set *
-lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
+lookup_header_set(struct ctl_table_root *root)
{
struct ctl_table_set *set = &root->default_set;
if (root->lookup)
- set = root->lookup(root, namespaces);
+ set = root->lookup(root);
return set;
}
@@ -491,7 +491,7 @@ static struct dentry *proc_sys_lookup(struct inode *dir, struct dentry *dentry,
goto out;
if (S_ISLNK(p->mode)) {
- ret = sysctl_follow_link(&h, &p, current->nsproxy);
+ ret = sysctl_follow_link(&h, &p);
err = ERR_PTR(ret);
if (ret)
goto out;
@@ -659,7 +659,7 @@ static bool proc_sys_link_fill_cache(struct file *file,
if (S_ISLNK(table->mode)) {
/* It is not an error if we can not follow the link ignore it */
- int err = sysctl_follow_link(&head, &table, current->nsproxy);
+ int err = sysctl_follow_link(&head, &table);
if (err)
goto out;
}
@@ -976,7 +976,7 @@ static struct ctl_dir *xlate_dir(struct ctl_table_set *set, struct ctl_dir *dir)
}
static int sysctl_follow_link(struct ctl_table_header **phead,
- struct ctl_table **pentry, struct nsproxy *namespaces)
+ struct ctl_table **pentry)
{
struct ctl_table_header *head;
struct ctl_table_root *root;
@@ -988,7 +988,7 @@ static int sysctl_follow_link(struct ctl_table_header **phead,
ret = 0;
spin_lock(&sysctl_lock);
root = (*pentry)->data;
- set = lookup_header_set(root, namespaces);
+ set = lookup_header_set(root);
dir = xlate_dir(set, (*phead)->parent);
if (IS_ERR(dir))
ret = PTR_ERR(dir);