diff options
65 files changed, 9967 insertions, 420 deletions
diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl index 16dca28ebf17..3fed97478058 100644 --- a/arch/alpha/kernel/syscalls/syscall.tbl +++ b/arch/alpha/kernel/syscalls/syscall.tbl @@ -509,3 +509,4 @@ 577 common open_tree_attr sys_open_tree_attr 578 common file_getattr sys_file_getattr 579 common file_setattr sys_file_setattr +580 common listns sys_listns diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index b07e699aaa3c..fd09afae72a2 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -484,3 +484,4 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns diff --git a/arch/arm64/tools/syscall_32.tbl b/arch/arm64/tools/syscall_32.tbl index 8d9088bc577d..8cdfe5d4dac9 100644 --- a/arch/arm64/tools/syscall_32.tbl +++ b/arch/arm64/tools/syscall_32.tbl @@ -481,3 +481,4 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl index f41d38dfbf13..871a5d67bf41 100644 --- a/arch/m68k/kernel/syscalls/syscall.tbl +++ b/arch/m68k/kernel/syscalls/syscall.tbl @@ -469,3 +469,4 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl index 580af574fe73..022fc85d94b3 100644 --- a/arch/microblaze/kernel/syscalls/syscall.tbl +++ b/arch/microblaze/kernel/syscalls/syscall.tbl @@ -475,3 +475,4 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl index d824ffe9a014..8cedc83c3266 100644 --- a/arch/mips/kernel/syscalls/syscall_n32.tbl +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl @@ -408,3 +408,4 @@ 467 n32 open_tree_attr sys_open_tree_attr 468 n32 file_getattr sys_file_getattr 469 n32 file_setattr sys_file_setattr +470 n32 listns sys_listns diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl index 7a7049c2c307..9b92bddf06b5 100644 --- a/arch/mips/kernel/syscalls/syscall_n64.tbl +++ b/arch/mips/kernel/syscalls/syscall_n64.tbl @@ -384,3 +384,4 @@ 467 n64 open_tree_attr sys_open_tree_attr 468 n64 file_getattr sys_file_getattr 469 n64 file_setattr sys_file_setattr +470 n64 listns sys_listns diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl index d330274f0601..f810b8a55716 100644 --- a/arch/mips/kernel/syscalls/syscall_o32.tbl +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl @@ -457,3 +457,4 @@ 467 o32 open_tree_attr sys_open_tree_attr 468 o32 file_getattr sys_file_getattr 469 o32 file_setattr sys_file_setattr +470 o32 listns sys_listns diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl index 88a788a7b18d..39bdacaa530b 100644 --- a/arch/parisc/kernel/syscalls/syscall.tbl +++ b/arch/parisc/kernel/syscalls/syscall.tbl @@ -468,3 +468,4 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl index b453e80dfc00..ec4458cdb97b 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -560,3 +560,4 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl index 8a6744d658db..5863787ab036 100644 --- a/arch/s390/kernel/syscalls/syscall.tbl +++ b/arch/s390/kernel/syscalls/syscall.tbl @@ -472,3 +472,4 @@ 467 common open_tree_attr sys_open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr sys_file_setattr +470 common listns sys_listns sys_listns diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl index 5e9c9eff5539..969c11325ade 100644 --- a/arch/sh/kernel/syscalls/syscall.tbl +++ b/arch/sh/kernel/syscalls/syscall.tbl @@ -473,3 +473,4 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl index ebb7d06d1044..39aa26b6a50b 100644 --- a/arch/sparc/kernel/syscalls/syscall.tbl +++ b/arch/sparc/kernel/syscalls/syscall.tbl @@ -515,3 +515,4 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index 4877e16da69a..e979a3eac7a3 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -475,3 +475,4 @@ 467 i386 open_tree_attr sys_open_tree_attr 468 i386 file_getattr sys_file_getattr 469 i386 file_setattr sys_file_setattr +470 i386 listns sys_listns diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index ced2a1deecd7..8a4ac4841be6 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -394,6 +394,7 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns # # Due to a historical design error, certain syscalls are numbered differently diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl index 374e4cb788d8..438a3b170402 100644 --- a/arch/xtensa/kernel/syscalls/syscall.tbl +++ b/arch/xtensa/kernel/syscalls/syscall.tbl @@ -440,3 +440,4 @@ 467 common open_tree_attr sys_open_tree_attr 468 common file_getattr sys_file_getattr 469 common file_setattr sys_file_setattr +470 common listns sys_listns diff --git a/fs/libfs.c b/fs/libfs.c index 96e3d7fc7fc6..1661dcb7d983 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -680,6 +680,7 @@ static int pseudo_fs_fill_super(struct super_block *s, struct fs_context *fc) s->s_export_op = ctx->eops; s->s_xattr = ctx->xattr; s->s_time_gran = 1; + s->s_d_flags |= ctx->s_d_flags; root = new_inode(s); if (!root) return -ENOMEM; diff --git a/fs/mount.h b/fs/mount.h index f13a28752d0b..2d28ef2a3aed 100644 --- a/fs/mount.h +++ b/fs/mount.h @@ -27,6 +27,7 @@ struct mnt_namespace { unsigned int nr_mounts; /* # of mounts in the namespace */ unsigned int pending_mounts; refcount_t passive; /* number references not pinning @mounts */ + bool is_anon; } __randomize_layout; struct mnt_pcp { @@ -175,7 +176,7 @@ static inline bool is_local_mountpoint(const struct dentry *dentry) static inline bool is_anon_ns(struct mnt_namespace *ns) { - return ns->ns.ns_id == 0; + return ns->is_anon; } static inline bool anon_ns_root(const struct mount *m) diff --git a/fs/namespace.c b/fs/namespace.c index a7fd9682bcf9..d7afac807ac3 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -4090,8 +4090,9 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns, bool a dec_mnt_namespaces(ucounts); return ERR_PTR(ret); } - if (!anon) - ns_tree_gen_id(&new_ns->ns); + ns_tree_gen_id(new_ns); + + new_ns->is_anon = anon; refcount_set(&new_ns->passive, 1); new_ns->mounts = RB_ROOT; init_waitqueue_head(&new_ns->poll); @@ -5982,11 +5983,8 @@ SYSCALL_DEFINE4(listmount, const struct mnt_id_req __user *, req, } struct mnt_namespace init_mnt_ns = { - .ns.inum = ns_init_inum(&init_mnt_ns), - .ns.ops = &mntns_operations, + .ns = NS_COMMON_INIT(init_mnt_ns), .user_ns = &init_user_ns, - .ns.__ns_ref = REFCOUNT_INIT(1), - .ns.ns_type = ns_common_type(&init_mnt_ns), .passive = REFCOUNT_INIT(1), .mounts = RB_ROOT, .poll = __WAIT_QUEUE_HEAD_INITIALIZER(init_mnt_ns.poll), diff --git a/fs/nsfs.c b/fs/nsfs.c index 79b026a36fb6..a80f8d2a4122 100644 --- a/fs/nsfs.c +++ b/fs/nsfs.c @@ -58,6 +58,8 @@ const struct dentry_operations ns_dentry_operations = { static void nsfs_evict(struct inode *inode) { struct ns_common *ns = inode->i_private; + + __ns_ref_active_put(ns); clear_inode(inode); ns->ops->put(ns); } @@ -408,6 +410,7 @@ static const struct super_operations nsfs_ops = { .statfs = simple_statfs, .evict_inode = nsfs_evict, .show_path = nsfs_show_path, + .drop_inode = inode_just_drop, }; static int nsfs_init_inode(struct inode *inode, void *data) @@ -418,6 +421,16 @@ static int nsfs_init_inode(struct inode *inode, void *data) inode->i_mode |= S_IRUGO; inode->i_fop = &ns_file_operations; inode->i_ino = ns->inum; + + /* + * Bring the namespace subtree back to life if we have to. This + * can happen when e.g., all processes using a network namespace + * and all namespace files or namespace file bind-mounts have + * died but there are still sockets pinning it. The SIOCGSKNS + * ioctl on such a socket will resurrect the relevant namespace + * subtree. + */ + __ns_ref_active_get(ns); return 0; } @@ -458,6 +471,45 @@ static int nsfs_encode_fh(struct inode *inode, u32 *fh, int *max_len, return FILEID_NSFS; } +bool is_current_namespace(struct ns_common *ns) +{ + switch (ns->ns_type) { +#ifdef CONFIG_CGROUPS + case CLONE_NEWCGROUP: + return current_in_namespace(to_cg_ns(ns)); +#endif +#ifdef CONFIG_IPC_NS + case CLONE_NEWIPC: + return current_in_namespace(to_ipc_ns(ns)); +#endif + case CLONE_NEWNS: + return current_in_namespace(to_mnt_ns(ns)); +#ifdef CONFIG_NET_NS + case CLONE_NEWNET: + return current_in_namespace(to_net_ns(ns)); +#endif +#ifdef CONFIG_PID_NS + case CLONE_NEWPID: + return current_in_namespace(to_pid_ns(ns)); +#endif +#ifdef CONFIG_TIME_NS + case CLONE_NEWTIME: + return current_in_namespace(to_time_ns(ns)); +#endif +#ifdef CONFIG_USER_NS + case CLONE_NEWUSER: + return current_in_namespace(to_user_ns(ns)); +#endif +#ifdef CONFIG_UTS_NS + case CLONE_NEWUTS: + return current_in_namespace(to_uts_ns(ns)); +#endif + default: + VFS_WARN_ON_ONCE(true); + return false; + } +} + static struct dentry *nsfs_fh_to_dentry(struct super_block *sb, struct fid *fh, int fh_len, int fh_type) { @@ -483,18 +535,35 @@ static struct dentry *nsfs_fh_to_dentry(struct super_block *sb, struct fid *fh, return NULL; } + if (!fid->ns_id) + return NULL; + /* Either both are set or both are unset. */ + if (!fid->ns_inum != !fid->ns_type) + return NULL; + scoped_guard(rcu) { ns = ns_tree_lookup_rcu(fid->ns_id, fid->ns_type); if (!ns) return NULL; VFS_WARN_ON_ONCE(ns->ns_id != fid->ns_id); - VFS_WARN_ON_ONCE(ns->ns_type != fid->ns_type); - if (ns->inum != fid->ns_inum) + if (fid->ns_inum && (fid->ns_inum != ns->inum)) + return NULL; + if (fid->ns_type && (fid->ns_type != ns->ns_type)) return NULL; - if (!__ns_ref_get(ns)) + /* + * This is racy because we're not actually taking an + * active reference. IOW, it could happen that the + * namespace becomes inactive after this check. + * We don't care because nsfs_init_inode() will just + * resurrect the relevant namespace tree for us. If it + * has been active here we just allow it's resurrection. + * We could try to take an active reference here and + * then drop it again. But really, why bother. + */ + if (!ns_get_unless_inactive(ns)) return NULL; } @@ -590,6 +659,8 @@ static int nsfs_init_fs_context(struct fs_context *fc) struct pseudo_fs_context *ctx = init_pseudo(fc, NSFS_MAGIC); if (!ctx) return -ENOMEM; + fc->s_iflags |= SB_I_NOEXEC | SB_I_NODEV; + ctx->s_d_flags |= DCACHE_DONTCACHE; ctx->ops = &nsfs_ops; ctx->eops = &nsfs_export_operations; ctx->dops = &ns_dentry_operations; @@ -612,3 +683,27 @@ void __init nsfs_init(void) nsfs_root_path.mnt = nsfs_mnt; nsfs_root_path.dentry = nsfs_mnt->mnt_root; } + +void nsproxy_ns_active_get(struct nsproxy *ns) +{ + ns_ref_active_get(ns->mnt_ns); + ns_ref_active_get(ns->uts_ns); + ns_ref_active_get(ns->ipc_ns); + ns_ref_active_get(ns->pid_ns_for_children); + ns_ref_active_get(ns->cgroup_ns); + ns_ref_active_get(ns->net_ns); + ns_ref_active_get(ns->time_ns); + ns_ref_active_get(ns->time_ns_for_children); +} + +void nsproxy_ns_active_put(struct nsproxy *ns) +{ + ns_ref_active_put(ns->mnt_ns); + ns_ref_active_put(ns->uts_ns); + ns_ref_active_put(ns->ipc_ns); + ns_ref_active_put(ns->pid_ns_for_children); + ns_ref_active_put(ns->cgroup_ns); + ns_ref_active_put(ns->net_ns); + ns_ref_active_put(ns->time_ns); + ns_ref_active_put(ns->time_ns_for_children); +} diff --git a/fs/pidfs.c b/fs/pidfs.c index 0ef5b47d796a..78dee3c201af 100644 --- a/fs/pidfs.c +++ b/fs/pidfs.c @@ -454,7 +454,6 @@ static long pidfd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) struct task_struct *task __free(put_task) = NULL; struct nsproxy *nsp __free(put_nsproxy) = NULL; struct ns_common *ns_common = NULL; - struct pid_namespace *pid_ns; if (!pidfs_ioctl_valid(cmd)) return -ENOIOCTLCMD; @@ -496,66 +495,64 @@ static long pidfd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) switch (cmd) { /* Namespaces that hang of nsproxy. */ case PIDFD_GET_CGROUP_NAMESPACE: - if (IS_ENABLED(CONFIG_CGROUPS)) { - get_cgroup_ns(nsp->cgroup_ns); - ns_common = to_ns_common(nsp->cgroup_ns); - } + if (!ns_ref_get(nsp->cgroup_ns)) + break; + ns_common = to_ns_common(nsp->cgroup_ns); break; case PIDFD_GET_IPC_NAMESPACE: - if (IS_ENABLED(CONFIG_IPC_NS)) { - get_ipc_ns(nsp->ipc_ns); - ns_common = to_ns_common(nsp->ipc_ns); - } + if (!ns_ref_get(nsp->ipc_ns)) + break; + ns_common = to_ns_common(nsp->ipc_ns); break; case PIDFD_GET_MNT_NAMESPACE: - get_mnt_ns(nsp->mnt_ns); + if (!ns_ref_get(nsp->mnt_ns)) + break; ns_common = to_ns_common(nsp->mnt_ns); break; case PIDFD_GET_NET_NAMESPACE: - if (IS_ENABLED(CONFIG_NET_NS)) { - ns_common = to_ns_common(nsp->net_ns); - get_net_ns(ns_common); - } + if (!ns_ref_get(nsp->net_ns)) + break; + ns_common = to_ns_common(nsp->net_ns); break; case PIDFD_GET_PID_FOR_CHILDREN_NAMESPACE: - if (IS_ENABLED(CONFIG_PID_NS)) { - get_pid_ns(nsp->pid_ns_for_children); - ns_common = to_ns_common(nsp->pid_ns_for_children); - } + if (!ns_ref_get(nsp->pid_ns_for_children)) + break; + ns_common = to_ns_common(nsp->pid_ns_for_children); break; case PIDFD_GET_TIME_NAMESPACE: - if (IS_ENABLED(CONFIG_TIME_NS)) { - get_time_ns(nsp->time_ns); - ns_common = to_ns_common(nsp->time_ns); - } + if (!ns_ref_get(nsp->time_ns)) + break; + ns_common = to_ns_common(nsp->time_ns); break; case PIDFD_GET_TIME_FOR_CHILDREN_NAMESPACE: - if (IS_ENABLED(CONFIG_TIME_NS)) { - get_time_ns(nsp->time_ns_for_children); - ns_common = to_ns_common(nsp->time_ns_for_children); - } + if (!ns_ref_get(nsp->time_ns_for_children)) + break; + ns_common = to_ns_common(nsp->time_ns_for_children); break; case PIDFD_GET_UTS_NAMESPACE: - if (IS_ENABLED(CONFIG_UTS_NS)) { - get_uts_ns(nsp->uts_ns); - ns_common = to_ns_common(nsp->uts_ns); - } + if (!ns_ref_get(nsp->uts_ns)) + break; + ns_common = to_ns_common(nsp->uts_ns); break; /* Namespaces that don't hang of nsproxy. */ case PIDFD_GET_USER_NAMESPACE: - if (IS_ENABLED(CONFIG_USER_NS)) { - rcu_read_lock(); - ns_common = to_ns_common(get_user_ns(task_cred_xxx(task, user_ns))); - rcu_read_unlock(); + scoped_guard(rcu) { + struct user_namespace *user_ns; + + user_ns = task_cred_xxx(task, user_ns); + if (!ns_ref_get(user_ns)) + break; + ns_common = to_ns_common(user_ns); } break; case PIDFD_GET_PID_NAMESPACE: - if (IS_ENABLED(CONFIG_PID_NS)) { - rcu_read_lock(); + scoped_guard(rcu) { + struct pid_namespace *pid_ns; + pid_ns = task_active_pid_ns(task); - if (pid_ns) - ns_common = to_ns_common(get_pid_ns(pid_ns)); - rcu_read_unlock(); + if (!ns_ref_get(pid_ns)) + break; + ns_common = to_ns_common(pid_ns); } break; default: @@ -1022,6 +1019,7 @@ static int pidfs_init_fs_context(struct fs_context *fc) fc->s_iflags |= SB_I_NOEXEC; fc->s_iflags |= SB_I_NODEV; + ctx->s_d_flags |= DCACHE_DONTCACHE; ctx->ops = &pidfs_sops; ctx->eops = &pidfs_export_operations; ctx->dops = &pidfs_dentry_operations; diff --git a/include/linux/ns/ns_common_types.h b/include/linux/ns/ns_common_types.h new file mode 100644 index 000000000000..b332b019b29c --- /dev/null +++ b/include/linux/ns/ns_common_types.h @@ -0,0 +1,196 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_NS_COMMON_TYPES_H +#define _LINUX_NS_COMMON_TYPES_H + +#include <linux/atomic.h> +#include <linux/ns/nstree_types.h> +#include <linux/rbtree.h> +#include <linux/refcount.h> +#include <linux/types.h> + |