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Diffstat (limited to 'fs/namespace.c')
-rw-r--r--fs/namespace.c108
1 files changed, 73 insertions, 35 deletions
diff --git a/fs/namespace.c b/fs/namespace.c
index c8519302f582..cc4926d53e7d 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -65,6 +65,15 @@ static int __init set_mphash_entries(char *str)
}
__setup("mphash_entries=", set_mphash_entries);
+static char * __initdata initramfs_options;
+static int __init initramfs_options_setup(char *str)
+{
+ initramfs_options = str;
+ return 1;
+}
+
+__setup("initramfs_options=", initramfs_options_setup);
+
static u64 event;
static DEFINE_IDA(mnt_id_ida);
static DEFINE_IDA(mnt_group_ida);
@@ -144,7 +153,7 @@ static void mnt_ns_release(struct mnt_namespace *ns)
lockdep_assert_not_held(&mnt_ns_tree_lock);
/* keep alive for {list,stat}mount() */
- if (refcount_dec_and_test(&ns->passive)) {
+ if (ns && refcount_dec_and_test(&ns->passive)) {
put_user_ns(ns->user_ns);
kfree(ns);
}
@@ -5200,7 +5209,6 @@ static int grab_requested_root(struct mnt_namespace *ns, struct path *root)
static int do_statmount(struct kstatmount *s, u64 mnt_id, u64 mnt_ns_id,
struct mnt_namespace *ns)
{
- struct path root __free(path_put) = {};
struct mount *m;
int err;
@@ -5212,7 +5220,7 @@ static int do_statmount(struct kstatmount *s, u64 mnt_id, u64 mnt_ns_id,
if (!s->mnt)
return -ENOENT;
- err = grab_requested_root(ns, &root);
+ err = grab_requested_root(ns, &s->root);
if (err)
return err;
@@ -5221,15 +5229,13 @@ static int do_statmount(struct kstatmount *s, u64 mnt_id, u64 mnt_ns_id,
* mounts to show users.
*/
m = real_mount(s->mnt);
- if (!is_path_reachable(m, m->mnt.mnt_root, &root) &&
+ if (!is_path_reachable(m, m->mnt.mnt_root, &s->root) &&
!ns_capable_noaudit(ns->user_ns, CAP_SYS_ADMIN))
return -EPERM;
err = security_sb_statfs(s->mnt->mnt_root);
if (err)
return err;
-
- s->root = root;
if (s->mask & STATMOUNT_SB_BASIC)
statmount_sb_basic(s);
@@ -5406,28 +5412,40 @@ retry:
if (!ret)
ret = copy_statmount_to_user(ks);
kvfree(ks->seq.buf);
+ path_put(&ks->root);
if (retry_statmount(ret, &seq_size))
goto retry;
return ret;
}
-static ssize_t do_listmount(struct mnt_namespace *ns, u64 mnt_parent_id,
- u64 last_mnt_id, u64 *mnt_ids, size_t nr_mnt_ids,
- bool reverse)
+struct klistmount {
+ u64 last_mnt_id;
+ u64 mnt_parent_id;
+ u64 *kmnt_ids;
+ u32 nr_mnt_ids;
+ struct mnt_namespace *ns;
+ struct path root;
+};
+
+static ssize_t do_listmount(struct klistmount *kls, bool reverse)
{
- struct path root __free(path_put) = {};
+ struct mnt_namespace *ns = kls->ns;
+ u64 mnt_parent_id = kls->mnt_parent_id;
+ u64 last_mnt_id = kls->last_mnt_id;
+ u64 *mnt_ids = kls->kmnt_ids;
+ size_t nr_mnt_ids = kls->nr_mnt_ids;
struct path orig;
struct mount *r, *first;
ssize_t ret;
rwsem_assert_held(&namespace_sem);
- ret = grab_requested_root(ns, &root);
+ ret = grab_requested_root(ns, &kls->root);
if (ret)
return ret;
if (mnt_parent_id == LSMT_ROOT) {
- orig = root;
+ orig = kls->root;
} else {
orig.mnt = lookup_mnt_in_ns(mnt_parent_id, ns);
if (!orig.mnt)
@@ -5439,7 +5457,7 @@ static ssize_t do_listmount(struct mnt_namespace *ns, u64 mnt_parent_id,
* Don't trigger audit denials. We just want to determine what
* mounts to show users.
*/
- if (!is_path_reachable(real_mount(orig.mnt), orig.dentry, &root) &&
+ if (!is_path_reachable(real_mount(orig.mnt), orig.dentry, &kls->root) &&
!ns_capable_noaudit(ns->user_ns, CAP_SYS_ADMIN))
return -EPERM;
@@ -5472,14 +5490,45 @@ static ssize_t do_listmount(struct mnt_namespace *ns, u64 mnt_parent_id,
return ret;
}
+static void __free_klistmount_free(const struct klistmount *kls)
+{
+ path_put(&kls->root);
+ kvfree(kls->kmnt_ids);
+ mnt_ns_release(kls->ns);
+}
+
+static inline int prepare_klistmount(struct klistmount *kls, struct mnt_id_req *kreq,
+ size_t nr_mnt_ids)
+{
+
+ u64 last_mnt_id = kreq->param;
+
+ /* The first valid unique mount id is MNT_UNIQUE_ID_OFFSET + 1. */
+ if (last_mnt_id != 0 && last_mnt_id <= MNT_UNIQUE_ID_OFFSET)
+ return -EINVAL;
+
+ kls->last_mnt_id = last_mnt_id;
+
+ kls->nr_mnt_ids = nr_mnt_ids;
+ kls->kmnt_ids = kvmalloc_array(nr_mnt_ids, sizeof(*kls->kmnt_ids),
+ GFP_KERNEL_ACCOUNT);
+ if (!kls->kmnt_ids)
+ return -ENOMEM;
+
+ kls->ns = grab_requested_mnt_ns(kreq);
+ if (!kls->ns)
+ return -ENOENT;
+
+ kls->mnt_parent_id = kreq->mnt_id;
+ return 0;
+}
+
SYSCALL_DEFINE4(listmount, const struct mnt_id_req __user *, req,
u64 __user *, mnt_ids, size_t, nr_mnt_ids, unsigned int, flags)
{
- u64 *kmnt_ids __free(kvfree) = NULL;
+ struct klistmount kls __free(klistmount_free) = {};
const size_t maxcount = 1000000;
- struct mnt_namespace *ns __free(mnt_ns_release) = NULL;
struct mnt_id_req kreq;
- u64 last_mnt_id;
ssize_t ret;
if (flags & ~LISTMOUNT_REVERSE)
@@ -5500,31 +5549,20 @@ SYSCALL_DEFINE4(listmount, const struct mnt_id_req __user *, req,
if (ret)
return ret;
- last_mnt_id = kreq.param;
- /* The first valid unique mount id is MNT_UNIQUE_ID_OFFSET + 1. */
- if (last_mnt_id != 0 && last_mnt_id <= MNT_UNIQUE_ID_OFFSET)
- return -EINVAL;
-
- kmnt_ids = kvmalloc_array(nr_mnt_ids, sizeof(*kmnt_ids),
- GFP_KERNEL_ACCOUNT);
- if (!kmnt_ids)
- return -ENOMEM;
-
- ns = grab_requested_mnt_ns(&kreq);
- if (!ns)
- return -ENOENT;
+ ret = prepare_klistmount(&kls, &kreq, nr_mnt_ids);
+ if (ret)
+ return ret;
- if (kreq.mnt_ns_id && (ns != current->nsproxy->mnt_ns) &&
- !ns_capable_noaudit(ns->user_ns, CAP_SYS_ADMIN))
+ if (kreq.mnt_ns_id && (kls.ns != current->nsproxy->mnt_ns) &&
+ !ns_capable_noaudit(kls.ns->user_ns, CAP_SYS_ADMIN))
return -ENOENT;
scoped_guard(rwsem_read, &namespace_sem)
- ret = do_listmount(ns, kreq.mnt_id, last_mnt_id, kmnt_ids,
- nr_mnt_ids, (flags & LISTMOUNT_REVERSE));
+ ret = do_listmount(&kls, (flags & LISTMOUNT_REVERSE));
if (ret <= 0)
return ret;
- if (copy_to_user(mnt_ids, kmnt_ids, ret * sizeof(*mnt_ids)))
+ if (copy_to_user(mnt_ids, kls.kmnt_ids, ret * sizeof(*mnt_ids)))
return -EFAULT;
return ret;
@@ -5537,7 +5575,7 @@ static void __init init_mount_tree(void)
struct mnt_namespace *ns;
struct path root;
- mnt = vfs_kern_mount(&rootfs_fs_type, 0, "rootfs", NULL);
+ mnt = vfs_kern_mount(&rootfs_fs_type, 0, "rootfs", initramfs_options);
if (IS_ERR(mnt))
panic("Can't create rootfs");
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-22 02:41:09 +0000