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Merge 5.15.52 into android14-5.15

Browse Source 
Changes in 5.15.52
	tick/nohz: unexport __init-annotated tick_nohz_full_setup()
	x86, kvm: use proper ASM macros for kvm_vcpu_is_preempted
	bcache: memset on stack variables in bch_btree_check() and bch_sectors_dirty_init()
	xfs: use kmem_cache_free() for kmem_cache objects
	xfs: punch out data fork delalloc blocks on COW writeback failure
	xfs: Fix the free logic of state in xfs_attr_node_hasname
	xfs: remove all COW fork extents when remounting readonly
	xfs: check sb_meta_uuid for dabuf buffer recovery
	xfs: prevent UAF in xfs_log_item_in_current_chkpt
	xfs: only bother with sync_filesystem during readonly remount
	powerpc/ftrace: Remove ftrace init tramp once kernel init is complete
	fs: add is_idmapped_mnt() helper
	fs: move mapping helpers
	fs: tweak fsuidgid_has_mapping()
	fs: account for filesystem mappings
	docs: update mapping documentation
	fs: use low-level mapping helpers
	fs: remove unused low-level mapping helpers
	fs: port higher-level mapping helpers
	fs: add i_user_ns() helper
	fs: support mapped mounts of mapped filesystems
	fs: fix acl translation
	fs: account for group membership
	rtw88: 8821c: support RFE type4 wifi NIC
	rtw88: rtw8821c: enable rfe 6 devices
	net: mscc: ocelot: allow unregistered IP multicast flooding to CPU
	io_uring: fix not locked access to fixed buf table
	Linux 5.15.52

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Icfb690703efd8cab1dffa7ca6cce28bbca635c3d
This commit is contained in:
Greg Kroah-Hartman
2022-07-13 12:08:48 +02:00
parent 99387927eb 545aecd229
commit fae17cd97d
37 changed files with 490 additions and 288 deletions
Download Patch File Download Diff File Expand all files Collapse all files

72
Documentation/filesystems/idmappings.rst
View File

@@ -952,75 +952,3 @@ The raw userspace id that is put on disk is ``u1000`` so when the user takes
their home directory back to their home computer where they are assigned
``u1000`` using the initial idmapping and mount the filesystem with the initial
idmapping they will see all those files owned by ``u1000``.
Shortcircuting
--------------
Currently, the implementation of idmapped mounts enforces that the filesystem
is mounted with the initial idmapping. The reason is simply that none of the
filesystems that we targeted were mountable with a non-initial idmapping. But
that might change soon enough. As we've seen above, thanks to the properties of
idmappings the translation works for both filesystems mounted with the initial
idmapping and filesystem with non-initial idmappings.
Based on this current restriction to filesystem mounted with the initial
idmapping two noticeable shortcuts have been taken:
1. We always stash a reference to the initial user namespace in ``struct
vfsmount``. Idmapped mounts are thus mounts that have a non-initial user
namespace attached to them.
In order to support idmapped mounts this needs to be changed. Instead of
stashing the initial user namespace the user namespace the filesystem was
mounted with must be stashed. An idmapped mount is then any mount that has
a different user namespace attached then the filesystem was mounted with.
This has no user-visible consequences.
2. The translation algorithms in ``mapped_fs*id()`` and ``i_*id_into_mnt()``
are simplified.
Let's consider ``mapped_fs*id()`` first. This function translates the
caller's kernel id into a kernel id in the filesystem's idmapping via
a mount's idmapping. The full algorithm is::
mapped_fsuid(kid):
/* Map the kernel id up into a userspace id in the mount's idmapping. */
from_kuid(mount-idmapping, kid) = uid
/* Map the userspace id down into a kernel id in the filesystem's idmapping. */
make_kuid(filesystem-idmapping, uid) = kuid
We know that the filesystem is always mounted with the initial idmapping as
we enforce this in ``mount_setattr()``. So this can be shortened to::
mapped_fsuid(kid):
/* Map the kernel id up into a userspace id in the mount's idmapping. */
from_kuid(mount-idmapping, kid) = uid
/* Map the userspace id down into a kernel id in the filesystem's idmapping. */
KUIDT_INIT(uid) = kuid
Similarly, for ``i_*id_into_mnt()`` which translated the filesystem's kernel
id into a mount's kernel id::
i_uid_into_mnt(kid):
/* Map the kernel id up into a userspace id in the filesystem's idmapping. */
from_kuid(filesystem-idmapping, kid) = uid
/* Map the userspace id down into a kernel id in the mounts's idmapping. */
make_kuid(mount-idmapping, uid) = kuid
Again, we know that the filesystem is always mounted with the initial
idmapping as we enforce this in ``mount_setattr()``. So this can be
shortened to::
i_uid_into_mnt(kid):
/* Map the kernel id up into a userspace id in the filesystem's idmapping. */
__kuid_val(kid) = uid
/* Map the userspace id down into a kernel id in the mounts's idmapping. */
make_kuid(mount-idmapping, uid) = kuid
Handling filesystems mounted with non-initial idmappings requires that the
translation functions be converted to their full form. They can still be
shortcircuited on non-idmapped mounts. This has no user-visible consequences.

2
Makefile
View File

@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
VERSION = 5
PATCHLEVEL = 15
SUBLEVEL = 51
SUBLEVEL = 52
EXTRAVERSION =
NAME = Trick or Treat

4
arch/powerpc/include/asm/ftrace.h
View File

@@ -96,7 +96,7 @@ static inline bool arch_syscall_match_sym_name(const char *sym, const char *name
#endif /* PPC64_ELF_ABI_v1 */
#endif /* CONFIG_FTRACE_SYSCALLS */
#ifdef CONFIG_PPC64
#if defined(CONFIG_PPC64) && defined(CONFIG_FUNCTION_TRACER)
#include <asm/paca.h>
static inline void this_cpu_disable_ftrace(void)
@@ -120,11 +120,13 @@ static inline u8 this_cpu_get_ftrace_enabled(void)
return get_paca()->ftrace_enabled;
}
void ftrace_free_init_tramp(void);
#else /* CONFIG_PPC64 */
static inline void this_cpu_disable_ftrace(void) { }
static inline void this_cpu_enable_ftrace(void) { }
static inline void this_cpu_set_ftrace_enabled(u8 ftrace_enabled) { }
static inline u8 this_cpu_get_ftrace_enabled(void) { return 1; }
static inline void ftrace_free_init_tramp(void) { }
#endif /* CONFIG_PPC64 */
#endif /* !__ASSEMBLY__ */

15
arch/powerpc/kernel/trace/ftrace.c
View File

@@ -336,9 +336,7 @@ static int setup_mcount_compiler_tramp(unsigned long tramp)
/* Is this a known long jump tramp? */
for (i = 0; i < NUM_FTRACE_TRAMPS; i++)
if (!ftrace_tramps[i])
break;
else if (ftrace_tramps[i] == tramp)
if (ftrace_tramps[i] == tramp)
return 0;
/* Is this a known plt tramp? */
@@ -881,6 +879,17 @@ void arch_ftrace_update_code(int command)
extern unsigned int ftrace_tramp_text[], ftrace_tramp_init[];
void ftrace_free_init_tramp(void)
{
int i;
for (i = 0; i < NUM_FTRACE_TRAMPS && ftrace_tramps[i]; i++)
if (ftrace_tramps[i] == (unsigned long)ftrace_tramp_init) {
ftrace_tramps[i] = 0;
return;
}
}
int __init ftrace_dyn_arch_init(void)
{
int i;

2
arch/powerpc/mm/mem.c
View File

@@ -22,6 +22,7 @@
#include <asm/kasan.h>
#include <asm/svm.h>
#include <asm/mmzone.h>
#include <asm/ftrace.h>
#include <mm/mmu_decl.h>
@@ -314,6 +315,7 @@ void free_initmem(void)
mark_initmem_nx();
init_mem_is_free = true;
free_initmem_default(POISON_FREE_INITMEM);
ftrace_free_init_tramp();
}
/*

2
arch/x86/kernel/kvm.c
View File

@@ -948,7 +948,7 @@ asm(
"movq __per_cpu_offset(,%rdi,8), %rax;"
"cmpb $0, " __stringify(KVM_STEAL_TIME_preempted) "+steal_time(%rax);"
"setne %al;"
"ret;"
ASM_RET
".size __raw_callee_save___kvm_vcpu_is_preempted, .-__raw_callee_save___kvm_vcpu_is_preempted;"
".popsection");

1
drivers/md/bcache/btree.c
View File

@@ -2017,6 +2017,7 @@ int bch_btree_check(struct cache_set *c)
if (c->root->level == 0)
return 0;
memset(&check_state, 0, sizeof(struct btree_check_state));
check_state.c = c;
check_state.total_threads = bch_btree_chkthread_nr();
check_state.key_idx = 0;

1
drivers/md/bcache/writeback.c
View File

@@ -947,6 +947,7 @@ void bch_sectors_dirty_init(struct bcache_device *d)
return;
}
memset(&state, 0, sizeof(struct bch_dirty_init_state));
state.c = c;
state.d = d;
state.total_threads = bch_btre_dirty_init_thread_nr();

8
drivers/net/ethernet/mscc/ocelot.c
View File

@@ -2206,11 +2206,15 @@ int ocelot_init(struct ocelot *ocelot)
ocelot_rmw_rix(ocelot, ANA_PGID_PGID_PGID(BIT(ocelot->num_phys_ports)),
ANA_PGID_PGID_PGID(BIT(ocelot->num_phys_ports)),
ANA_PGID_PGID, PGID_MC);
ocelot_rmw_rix(ocelot, ANA_PGID_PGID_PGID(BIT(ocelot->num_phys_ports)),
ANA_PGID_PGID_PGID(BIT(ocelot->num_phys_ports)),
ANA_PGID_PGID, PGID_MCIPV4);
ocelot_rmw_rix(ocelot, ANA_PGID_PGID_PGID(BIT(ocelot->num_phys_ports)),
ANA_PGID_PGID_PGID(BIT(ocelot->num_phys_ports)),
ANA_PGID_PGID, PGID_MCIPV6);
ocelot_rmw_rix(ocelot, ANA_PGID_PGID_PGID(BIT(ocelot->num_phys_ports)),
ANA_PGID_PGID_PGID(BIT(ocelot->num_phys_ports)),
ANA_PGID_PGID, PGID_BC);
ocelot_write_rix(ocelot, 0, ANA_PGID_PGID, PGID_MCIPV4);
ocelot_write_rix(ocelot, 0, ANA_PGID_PGID, PGID_MCIPV6);
/* Allow manual injection via DEVCPU_QS registers, and byte swap these
* registers endianness.

14
drivers/net/wireless/realtek/rtw88/rtw8821c.c
View File

@@ -304,7 +304,8 @@ static void rtw8821c_set_channel_rf(struct rtw_dev *rtwdev, u8 channel, u8 bw)
if (channel <= 14) {
if (rtwdev->efuse.rfe_option == 0)
rtw8821c_switch_rf_set(rtwdev, SWITCH_TO_WLG);
else if (rtwdev->efuse.rfe_option == 2)
else if (rtwdev->efuse.rfe_option == 2 ||
rtwdev->efuse.rfe_option == 4)
rtw8821c_switch_rf_set(rtwdev, SWITCH_TO_BTG);
rtw_write_rf(rtwdev, RF_PATH_A, RF_LUTDBG, BIT(6), 0x1);
rtw_write_rf(rtwdev, RF_PATH_A, 0x64, 0xf, 0xf);
@@ -777,6 +778,15 @@ static void rtw8821c_coex_cfg_ant_switch(struct rtw_dev *rtwdev, u8 ctrl_type,
if (switch_status == coex_dm->cur_switch_status)
return;
if (coex_rfe->wlg_at_btg) {
ctrl_type = COEX_SWITCH_CTRL_BY_BBSW;
if (coex_rfe->ant_switch_polarity)
pos_type = COEX_SWITCH_TO_WLA;
else
pos_type = COEX_SWITCH_TO_WLG_BT;
}
coex_dm->cur_switch_status = switch_status;
if (coex_rfe->ant_switch_diversity &&
@@ -1502,6 +1512,8 @@ static const struct rtw_intf_phy_para_table phy_para_table_8821c = {
static const struct rtw_rfe_def rtw8821c_rfe_defs[] = {
[0] = RTW_DEF_RFE(8821c, 0, 0),
[2] = RTW_DEF_RFE_EXT(8821c, 0, 0, 2),
[4] = RTW_DEF_RFE_EXT(8821c, 0, 0, 2),
[6] = RTW_DEF_RFE(8821c, 0, 0),
};
static struct rtw_hw_reg rtw8821c_dig[] = {

22
fs/attr.c
View File

@@ -61,9 +61,15 @@ static bool chgrp_ok(struct user_namespace *mnt_userns,
const struct inode *inode, kgid_t gid)
{
kgid_t kgid = i_gid_into_mnt(mnt_userns, inode);
if (uid_eq(current_fsuid(), i_uid_into_mnt(mnt_userns, inode)) &&
(in_group_p(gid) || gid_eq(gid, inode->i_gid)))
if (uid_eq(current_fsuid(), i_uid_into_mnt(mnt_userns, inode))) {
kgid_t mapped_gid;
if (gid_eq(gid, inode->i_gid))
return true;
mapped_gid = mapped_kgid_fs(mnt_userns, i_user_ns(inode), gid);
if (in_group_p(mapped_gid))
return true;
}
if (capable_wrt_inode_uidgid(mnt_userns, inode, CAP_CHOWN))
return true;
if (gid_eq(kgid, INVALID_GID) &&
@@ -123,11 +129,19 @@ int setattr_prepare(struct user_namespace *mnt_userns, struct dentry *dentry,
/* Make sure a caller can chmod. */
if (ia_valid & ATTR_MODE) {
kgid_t mapped_gid;
if (!inode_owner_or_capable(mnt_userns, inode))
return -EPERM;
if (ia_valid & ATTR_GID)
mapped_gid = mapped_kgid_fs(mnt_userns,
i_user_ns(inode), attr->ia_gid);
else
mapped_gid = i_gid_into_mnt(mnt_userns, inode);
/* Also check the setgid bit! */
if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
i_gid_into_mnt(mnt_userns, inode)) &&
if (!in_group_p(mapped_gid) &&
!capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FSETID))
attr->ia_mode &= ~S_ISGID;
}

2
fs/cachefiles/bind.c
View File

@@ -117,7 +117,7 @@ static int cachefiles_daemon_add_cache(struct cachefiles_cache *cache)
root = path.dentry;
ret = -EINVAL;
if (mnt_user_ns(path.mnt) != &init_user_ns) {
if (is_idmapped_mnt(path.mnt)) {
pr_warn("File cache on idmapped mounts not supported");
goto error_unsupported;
}

2
fs/ecryptfs/main.c
View File

@@ -537,7 +537,7 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
goto out_free;
}
if (mnt_user_ns(path.mnt) != &init_user_ns) {
if (is_idmapped_mnt(path.mnt)) {
rc = -EINVAL;
printk(KERN_ERR "Mounting on idmapped mounts currently disallowed\n");
goto out_free;

26
fs/io_uring.c
View File

@@ -2932,15 +2932,24 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe,
kiocb->ki_complete = io_complete_rw;
}
/* used for fixed read/write too - just read unconditionally */
req->buf_index = READ_ONCE(sqe->buf_index);
req->imu = NULL;
if (req->opcode == IORING_OP_READ_FIXED ||
req->opcode == IORING_OP_WRITE_FIXED) {
req->imu = NULL;
struct io_ring_ctx *ctx = req->ctx;
u16 index;
if (unlikely(req->buf_index >= ctx->nr_user_bufs))
return -EFAULT;
index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
req->imu = ctx->user_bufs[index];
io_req_set_rsrc_node(req);
}
req->rw.addr = READ_ONCE(sqe->addr);
req->rw.len = READ_ONCE(sqe->len);
req->buf_index = READ_ONCE(sqe->buf_index);
return 0;
}
@@ -3066,18 +3075,9 @@ static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter
static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
{
struct io_ring_ctx *ctx = req->ctx;
struct io_mapped_ubuf *imu = req->imu;
u16 index, buf_index = req->buf_index;
if (likely(!imu)) {
if (unlikely(buf_index >= ctx->nr_user_bufs))
if (WARN_ON_ONCE(!req->imu))
return -EFAULT;
index = array_index_nospec(buf_index, ctx->nr_user_bufs);
imu = READ_ONCE(ctx->user_bufs[index]);
req->imu = imu;
}
return __io_import_fixed(req, rw, iter, imu);
return __io_import_fixed(req, rw, iter, req->imu);
}
static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)

19
fs/ksmbd/smbacl.c
View File

@@ -9,6 +9,7 @@
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/mnt_idmapping.h>
#include "smbacl.h"
#include "smb_common.h"
@@ -274,14 +275,7 @@ static int sid_to_id(struct user_namespace *user_ns,
uid_t id;
id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
/*
* Translate raw sid into kuid in the server's user
* namespace.
*/
uid = make_kuid(&init_user_ns, id);
/* If this is an idmapped mount, apply the idmapping. */
uid = kuid_from_mnt(user_ns, uid);
uid = mapped_kuid_user(user_ns, &init_user_ns, KUIDT_INIT(id));
if (uid_valid(uid)) {
fattr->cf_uid = uid;
rc = 0;
@@ -291,14 +285,7 @@ static int sid_to_id(struct user_namespace *user_ns,
gid_t id;
id = le32_to_cpu(psid->sub_auth[psid->num_subauth - 1]);
/*
* Translate raw sid into kgid in the server's user
* namespace.
*/
gid = make_kgid(&init_user_ns, id);
/* If this is an idmapped mount, apply the idmapping. */
gid = kgid_from_mnt(user_ns, gid);
gid = mapped_kgid_user(user_ns, &init_user_ns, KGIDT_INIT(id));
if (gid_valid(gid)) {
fattr->cf_gid = gid;
rc = 0;

5
fs/ksmbd/smbacl.h
View File

@@ -11,6 +11,7 @@
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/posix_acl.h>
#include <linux/mnt_idmapping.h>
#include "mgmt/tree_connect.h"
@@ -216,7 +217,7 @@ static inline uid_t posix_acl_uid_translate(struct user_namespace *mnt_userns,
kuid_t kuid;
/* If this is an idmapped mount, apply the idmapping. */
kuid = kuid_into_mnt(mnt_userns, pace->e_uid);
kuid = mapped_kuid_fs(mnt_userns, &init_user_ns, pace->e_uid);
/* Translate the kuid into a userspace id ksmbd would see. */
return from_kuid(&init_user_ns, kuid);
@@ -228,7 +229,7 @@ static inline gid_t posix_acl_gid_translate(struct user_namespace *mnt_userns,
kgid_t kgid;
/* If this is an idmapped mount, apply the idmapping. */
kgid = kgid_into_mnt(mnt_userns, pace->e_gid);
kgid = mapped_kgid_fs(mnt_userns, &init_user_ns, pace->e_gid);
/* Translate the kgid into a userspace id ksmbd would see. */
return from_kgid(&init_user_ns, kgid);

53
fs/namespace.c
View File

@@ -31,6 +31,7 @@
#include <uapi/linux/mount.h>
#include <linux/fs_context.h>
#include <linux/shmem_fs.h>
#include <linux/mnt_idmapping.h>
#include "pnode.h"
#include "internal.h"
@@ -561,7 +562,7 @@ static void free_vfsmnt(struct mount *mnt)
struct user_namespace *mnt_userns;
mnt_userns = mnt_user_ns(&mnt->mnt);
if (mnt_userns != &init_user_ns)
if (!initial_idmapping(mnt_userns))
put_user_ns(mnt_userns);
kfree_const(mnt->mnt_devname);
#ifdef CONFIG_SMP
@@ -965,6 +966,7 @@ static struct mount *skip_mnt_tree(struct mount *p)
struct vfsmount *vfs_create_mount(struct fs_context *fc)
{
struct mount *mnt;
struct user_namespace *fs_userns;
if (!fc->root)
return ERR_PTR(-EINVAL);
@@ -982,6 +984,10 @@ struct vfsmount *vfs_create_mount(struct fs_context *fc)
mnt->mnt_mountpoint = mnt->mnt.mnt_root;
mnt->mnt_parent = mnt;
fs_userns = mnt->mnt.mnt_sb->s_user_ns;
if (!initial_idmapping(fs_userns))
mnt->mnt.mnt_userns = get_user_ns(fs_userns);
lock_mount_hash();
list_add_tail(&mnt->mnt_instance, &mnt->mnt.mnt_sb->s_mounts);
unlock_mount_hash();
@@ -1072,7 +1078,7 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root,
atomic_inc(&sb->s_active);
mnt->mnt.mnt_userns = mnt_user_ns(&old->mnt);
if (mnt->mnt.mnt_userns != &init_user_ns)
if (!initial_idmapping(mnt->mnt.mnt_userns))
mnt->mnt.mnt_userns = get_user_ns(mnt->mnt.mnt_userns);
mnt->mnt.mnt_sb = sb;
mnt->mnt.mnt_root = dget(root);
@@ -3927,28 +3933,32 @@ static unsigned int recalc_flags(struct mount_kattr *kattr, struct mount *mnt)
static int can_idmap_mount(const struct mount_kattr *kattr, struct mount *mnt)
{
struct vfsmount *m = &mnt->mnt;
struct user_namespace *fs_userns = m->mnt_sb->s_user_ns;
if (!kattr->mnt_userns)
return 0;
/*
* Creating an idmapped mount with the filesystem wide idmapping
* doesn't make sense so block that. We don't allow mushy semantics.
*/
if (kattr->mnt_userns == fs_userns)
return -EINVAL;
/*
* Once a mount has been idmapped we don't allow it to change its
* mapping. It makes things simpler and callers can just create
* another bind-mount they can idmap if they want to.
*/
if (mnt_user_ns(m) != &init_user_ns)
if (is_idmapped_mnt(m))
return -EPERM;
/* The underlying filesystem doesn't support idmapped mounts yet. */
if (!(m->mnt_sb->s_type->fs_flags & FS_ALLOW_IDMAP))
return -EINVAL;
/* Don't yet support filesystem mountable in user namespaces. */
if (m->mnt_sb->s_user_ns != &init_user_ns)
return -EINVAL;
/* We're not controlling the superblock. */
if (!capable(CAP_SYS_ADMIN))
if (!ns_capable(fs_userns, CAP_SYS_ADMIN))
return -EPERM;
/* Mount has already been visible in the filesystem hierarchy. */
@@ -4002,14 +4012,27 @@ out:
static void do_idmap_mount(const struct mount_kattr *kattr, struct mount *mnt)
{
struct user_namespace *mnt_userns;
struct user_namespace *mnt_userns, *old_mnt_userns;
if (!kattr->mnt_userns)
return;
/*
* We're the only ones able to change the mount's idmapping. So
* mnt->mnt.mnt_userns is stable and we can retrieve it directly.
*/
old_mnt_userns = mnt->mnt.mnt_userns;
mnt_userns = get_user_ns(kattr->mnt_userns);
/* Pairs with smp_load_acquire() in mnt_user_ns(). */
smp_store_release(&mnt->mnt.mnt_userns, mnt_userns);
/*
* If this is an idmapped filesystem drop the reference we've taken
* in vfs_create_mount() before.
*/
if (!initial_idmapping(old_mnt_userns))
put_user_ns(old_mnt_userns);
}
static void mount_setattr_commit(struct mount_kattr *kattr,
@@ -4133,13 +4156,15 @@ static int build_mount_idmapped(const struct mount_attr *attr, size_t usize,
}
/*
* The init_user_ns is used to indicate that a vfsmount is not idmapped.
* This is simpler than just having to treat NULL as unmapped. Users
* wanting to idmap a mount to init_user_ns can just use a namespace
* with an identity mapping.
* The initial idmapping cannot be used to create an idmapped
* mount. We use the initial idmapping as an indicator of a mount
* that is not idmapped. It can simply be passed into helpers that
* are aware of idmapped mounts as a convenient shortcut. A user
* can just create a dedicated identity mapping to achieve the same
* result.
*/
mnt_userns = container_of(ns, struct user_namespace, ns);
if (mnt_userns == &init_user_ns) {
if (initial_idmapping(mnt_userns)) {
err = -EPERM;
goto out_fput;
}

2
fs/nfsd/export.c
View File

@@ -427,7 +427,7 @@ static int check_export(struct path *path, int *flags, unsigned char *uuid)
return -EINVAL;
}
if (mnt_user_ns(path->mnt) != &init_user_ns) {
if (is_idmapped_mnt(path->mnt)) {
dprintk("exp_export: export of idmapped mounts not yet supported.\n");
return -EINVAL;
}

8
fs/open.c
View File

@@ -32,6 +32,7 @@
#include <linux/ima.h>
#include <linux/dnotify.h>
#include <linux/compat.h>
#include <linux/mnt_idmapping.h>
#include "internal.h"
#include <trace/hooks/syscall_check.h>
@@ -641,7 +642,7 @@ SYSCALL_DEFINE2(chmod, const char __user *, filename, umode_t, mode)
int chown_common(const struct path *path, uid_t user, gid_t group)
{
struct user_namespace *mnt_userns;
struct user_namespace *mnt_userns, *fs_userns;
struct inode *inode = path->dentry->d_inode;
struct inode *delegated_inode = NULL;
int error;
@@ -653,8 +654,9 @@ int chown_common(const struct path *path, uid_t user, gid_t group)
gid = make_kgid(current_user_ns(), group);
mnt_userns = mnt_user_ns(path->mnt);
uid = kuid_from_mnt(mnt_userns, uid);
gid = kgid_from_mnt(mnt_userns, gid);
fs_userns = i_user_ns(inode);
uid = mapped_kuid_user(mnt_userns, fs_userns, uid);
gid = mapped_kgid_user(mnt_userns, fs_userns, gid);
retry_deleg:
newattrs.ia_valid = ATTR_CTIME;

2
fs/overlayfs/super.c
View File

@@ -895,7 +895,7 @@ static int ovl_mount_dir_noesc(const char *name, struct path *path)
pr_err("filesystem on '%s' not supported\n", name);
goto out_put;
}
if (mnt_user_ns(path->mnt) != &init_user_ns) {
if (is_idmapped_mnt(path->mnt)) {
pr_err("idmapped layers are currently not supported\n");
goto out_put;
}

27
fs/posix_acl.c
View File

@@ -23,6 +23,7 @@
#include <linux/export.h>
#include <linux/user_namespace.h>
#include <linux/namei.h>
#include <linux/mnt_idmapping.h>
static struct posix_acl **acl_by_type(struct inode *inode, int type)
{
@@ -375,7 +376,9 @@ posix_acl_permission(struct user_namespace *mnt_userns, struct inode *inode,
goto check_perm;
break;
case ACL_USER:
uid = kuid_into_mnt(mnt_userns, pa->e_uid);
uid = mapped_kuid_fs(mnt_userns,
i_user_ns(inode),
pa->e_uid);
if (uid_eq(uid, current_fsuid()))
goto mask;
break;
@@ -388,7 +391,9 @@ posix_acl_permission(struct user_namespace *mnt_userns, struct inode *inode,
}
break;
case ACL_GROUP:
gid = kgid_into_mnt(mnt_userns, pa->e_gid);
gid = mapped_kgid_fs(mnt_userns,
i_user_ns(inode),
pa->e_gid);
if (in_group_p(gid)) {
found = 1;
if ((pa->e_perm & want) == want)
@@ -735,17 +740,17 @@ static void posix_acl_fix_xattr_userns(
case ACL_USER:
uid = make_kuid(from, le32_to_cpu(entry->e_id));
if (from_user)
uid = kuid_from_mnt(mnt_userns, uid);
uid = mapped_kuid_user(mnt_userns, &init_user_ns, uid);
else
uid = kuid_into_mnt(mnt_userns, uid);
uid = mapped_kuid_fs(mnt_userns, &init_user_ns, uid);
entry->e_id = cpu_to_le32(from_kuid(to, uid));
break;
case ACL_GROUP:
gid = make_kgid(from, le32_to_cpu(entry->e_id));
if (from_user)
gid = kgid_from_mnt(mnt_userns, gid);
gid = mapped_kgid_user(mnt_userns, &init_user_ns, gid);
else
gid = kgid_into_mnt(mnt_userns, gid);
gid = mapped_kgid_fs(mnt_userns, &init_user_ns, gid);
entry->e_id = cpu_to_le32(from_kgid(to, gid));
break;
default:
@@ -755,9 +760,14 @@ static void posix_acl_fix_xattr_userns(
}
void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_userns,
struct inode *inode,
void *value, size_t size)
{
struct user_namespace *user_ns = current_user_ns();
/* Leave ids untouched on non-idmapped mounts. */
if (no_idmapping(mnt_userns, i_user_ns(inode)))
mnt_userns = &init_user_ns;
if ((user_ns == &init_user_ns) && (mnt_userns == &init_user_ns))
return;
posix_acl_fix_xattr_userns(&init_user_ns, user_ns, mnt_userns, value,
@@ -765,9 +775,14 @@ void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_userns,
}
void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_userns,
struct inode *inode,
void *value, size_t size)
{
struct user_namespace *user_ns = current_user_ns();
/* Leave ids untouched on non-idmapped mounts. */
if (no_idmapping(mnt_userns, i_user_ns(inode)))
mnt_userns = &init_user_ns;
if ((user_ns == &init_user_ns) && (mnt_userns == &init_user_ns))
return;
posix_acl_fix_xattr_userns(user_ns, &init_user_ns, mnt_userns, value,

2
fs/proc_namespace.c
View File

@@ -80,7 +80,7 @@ static void show_mnt_opts(struct seq_file *m, struct vfsmount *mnt)
seq_puts(m, fs_infop->str);
}
if (mnt_user_ns(mnt) != &init_user_ns)
if (is_idmapped_mnt(mnt))
seq_puts(m, ",idmapped");
}

6
fs/xattr.c
View File

@@ -569,7 +569,8 @@ setxattr(struct user_namespace *mnt_userns, struct dentry *d,
}
if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
(strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
posix_acl_fix_xattr_from_user(mnt_userns, kvalue, size);
posix_acl_fix_xattr_from_user(mnt_userns, d_inode(d),
kvalue, size);
}
error = vfs_setxattr(mnt_userns, d, kname, kvalue, size, flags);
@@ -667,7 +668,8 @@ getxattr(struct user_namespace *mnt_userns, struct dentry *d,
if (error > 0) {
if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
(strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
posix_acl_fix_xattr_to_user(mnt_userns, kvalue, error);
posix_acl_fix_xattr_to_user(mnt_userns, d_inode(d),
kvalue, error);
if (size && copy_to_user(value, kvalue, error))
error = -EFAULT;
} else if (error == -ERANGE && size >= XATTR_SIZE_MAX) {

17
fs/xfs/libxfs/xfs_attr.c
View File

@@ -1077,21 +1077,18 @@ xfs_attr_node_hasname(
state = xfs_da_state_alloc(args);
if (statep != NULL)
*statep = NULL;
*statep = state;
/*
* Search to see if name exists, and get back a pointer to it.
*/
error = xfs_da3_node_lookup_int(state, &retval);
if (error) {
xfs_da_state_free(state);
return error;
}
if (error)
retval = error;
if (statep != NULL)
*statep = state;
else
if (!statep)
xfs_da_state_free(state);
return retval;
}
@@ -1112,7 +1109,7 @@ xfs_attr_node_addname_find_attr(
*/
retval = xfs_attr_node_hasname(args, &dac->da_state);
if (retval != -ENOATTR && retval != -EEXIST)
return retval;
goto error;
if (retval == -ENOATTR && (args->attr_flags & XATTR_REPLACE))
goto error;
@@ -1337,7 +1334,7 @@ int xfs_attr_node_removename_setup(
error = xfs_attr_node_hasname(args, state);
if (error != -EEXIST)
return error;
goto out;
error = 0;
ASSERT((*state)->path.blk[(*state)->path.active - 1].bp != NULL);

15
fs/xfs/xfs_aops.c
View File

@@ -82,6 +82,7 @@ xfs_end_ioend(
struct iomap_ioend *ioend)
{
struct xfs_inode *ip = XFS_I(ioend->io_inode);
struct xfs_mount *mp = ip->i_mount;
xfs_off_t offset = ioend->io_offset;
size_t size = ioend->io_size;
unsigned int nofs_flag;
@@ -97,18 +98,26 @@ xfs_end_ioend(
/*
* Just clean up the in-memory structures if the fs has been shut down.
*/
if (xfs_is_shutdown(ip->i_mount)) {
if (xfs_is_shutdown(mp)) {
error = -EIO;
goto done;
}
/*
* Clean up any COW blocks on an I/O error.
* Clean up all COW blocks and underlying data fork delalloc blocks on
* I/O error. The delalloc punch is required because this ioend was
* mapped to blocks in the COW fork and the associated pages are no
* longer dirty. If we don't remove delalloc blocks here, they become
* stale and can corrupt free space accounting on unmount.
*/
error = blk_status_to_errno(ioend->io_bio->bi_status);
if (unlikely(error)) {
if (ioend->io_flags & IOMAP_F_SHARED)
if (ioend->io_flags & IOMAP_F_SHARED) {
xfs_reflink_cancel_cow_range(ip, offset, size, true);
xfs_bmap_punch_delalloc_range(ip,
XFS_B_TO_FSBT(mp, offset),
XFS_B_TO_FSB(mp, size));
}
goto done;
}

2
fs/xfs/xfs_buf_item_recover.c
View File

@@ -816,7 +816,7 @@ xlog_recover_get_buf_lsn(
}
if (lsn != (xfs_lsn_t)-1) {
if (!uuid_equal(&mp->m_sb.sb_uuid, uuid))
if (!uuid_equal(&mp->m_sb.sb_meta_uuid, uuid))
goto recover_immediately;
return lsn;
}

6
fs/xfs/xfs_extfree_item.c
View File

@@ -482,7 +482,7 @@ xfs_extent_free_finish_item(
free->xefi_startblock,
free->xefi_blockcount,
&free->xefi_oinfo, free->xefi_skip_discard);
kmem_free(free);
kmem_cache_free(xfs_bmap_free_item_zone, free);
return error;
}
@@ -502,7 +502,7 @@ xfs_extent_free_cancel_item(
struct xfs_extent_free_item *free;
free = container_of(item, struct xfs_extent_free_item, xefi_list);
kmem_free(free);
kmem_cache_free(xfs_bmap_free_item_zone, free);
}
const struct xfs_defer_op_type xfs_extent_free_defer_type = {
@@ -564,7 +564,7 @@ xfs_agfl_free_finish_item(
extp->ext_len = free->xefi_blockcount;
efdp->efd_next_extent++;
kmem_free(free);
kmem_cache_free(xfs_bmap_free_item_zone, free);
return error;
}

8
fs/xfs/xfs_inode.c
View File

@@ -994,8 +994,8 @@ xfs_create(
/*
* Make sure that we have allocated dquot(s) on disk.
*/
error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
mapped_fsgid(mnt_userns), prid,
error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns, &init_user_ns),
mapped_fsgid(mnt_userns, &init_user_ns), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
&udqp, &gdqp, &pdqp);
if (error)
@@ -1148,8 +1148,8 @@ xfs_create_tmpfile(
/*
* Make sure that we have allocated dquot(s) on disk.
*/
error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
mapped_fsgid(mnt_userns), prid,
error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns, &init_user_ns),
mapped_fsgid(mnt_userns, &init_user_ns), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
&udqp, &gdqp, &pdqp);
if (error)

1
fs/xfs/xfs_linux.h
View File

@@ -61,6 +61,7 @@ typedef __u32 xfs_nlink_t;
#include <linux/ratelimit.h>
#include <linux/rhashtable.h>
#include <linux/xattr.h>
#include <linux/mnt_idmapping.h>
#include <asm/page.h>
#include <asm/div64.h>

4
fs/xfs/xfs_log_cil.c
View File

@@ -1444,7 +1444,7 @@ bool
xfs_log_item_in_current_chkpt(
struct xfs_log_item *lip)
{
struct xfs_cil_ctx *ctx = lip->li_mountp->m_log->l_cilp->xc_ctx;
struct xfs_cil *cil = lip->li_mountp->m_log->l_cilp;
if (list_empty(&lip->li_cil))
return false;
@@ -1454,7 +1454,7 @@ xfs_log_item_in_current_chkpt(
* first checkpoint it is written to. Hence if it is different to the
* current sequence, we're in a new checkpoint.
*/
return lip->li_seq == ctx->sequence;
return lip->li_seq == READ_ONCE(cil->xc_current_sequence);
}
/*

19
fs/xfs/xfs_super.c
View File

@@ -1768,16 +1768,29 @@ static int
xfs_remount_ro(
struct xfs_mount *mp)
{
struct xfs_icwalk icw = {
.icw_flags = XFS_ICWALK_FLAG_SYNC,
};
int error;
/* Flush all the dirty data to disk. */
error = sync_filesystem(mp->m_super);
if (error)
return error;
/*
* Cancel background eofb scanning so it cannot race with the final
* log force+buftarg wait and deadlock the remount.
*/
xfs_blockgc_stop(mp);
/* Get rid of any leftover CoW reservations... */
error = xfs_blockgc_free_space(mp, NULL);
/*
* Clear out all remaining COW staging extents and speculative post-EOF
* preallocations so that we don't leave inodes requiring inactivation
* cleanups during reclaim on a read-only mount. We must process every
* cached inode, so this requires a synchronous cache scan.
*/
error = xfs_blockgc_free_space(mp, &icw);
if (error) {
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
return error;
@@ -1843,8 +1856,6 @@ xfs_fs_reconfigure(
if (error)
return error;
sync_filesystem(mp->m_super);
/* inode32 -> inode64 */
if (xfs_has_small_inums(mp) && !xfs_has_small_inums(new_mp)) {
mp->m_features &= ~XFS_FEAT_SMALL_INUMS;

4
fs/xfs/xfs_symlink.c
View File

@@ -184,8 +184,8 @@ xfs_symlink(
/*
* Make sure that we have allocated dquot(s) on disk.
*/
error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns),
mapped_fsgid(mnt_userns), prid,
error = xfs_qm_vop_dqalloc(dp, mapped_fsuid(mnt_userns, &init_user_ns),
mapped_fsgid(mnt_userns, &init_user_ns), prid,
XFS_QMOPT_QUOTALL | XFS_QMOPT_INHERIT,
&udqp, &gdqp, &pdqp);
if (error)

141
include/linux/fs.h
View File

@@ -41,6 +41,7 @@
#include <linux/stddef.h>
#include <linux/mount.h>
#include <linux/cred.h>
#include <linux/mnt_idmapping.h>
#include <linux/android_kabi.h>
#include <asm/byteorder.h>
@@ -1633,6 +1634,11 @@ struct super_block {
ANDROID_KABI_RESERVE(4);
} __randomize_layout;
static inline struct user_namespace *i_user_ns(const struct inode *inode)
{
return inode->i_sb->s_user_ns;
}
/* Helper functions so that in most cases filesystems will
* not need to deal directly with kuid_t and kgid_t and can
* instead deal with the raw numeric values that are stored
@@ -1640,50 +1646,22 @@ struct super_block {
*/
static inline uid_t i_uid_read(const struct inode *inode)
{
return from_kuid(inode->i_sb->s_user_ns, inode->i_uid);
return from_kuid(i_user_ns(inode), inode->i_uid);
}
static inline gid_t i_gid_read(const struct inode *inode)
{
return from_kgid(inode->i_sb->s_user_ns, inode->i_gid);
return from_kgid(i_user_ns(inode), inode->i_gid);
}
static inline void i_uid_write(struct inode *inode, uid_t uid)
{
inode->i_uid = make_kuid(inode->i_sb->s_user_ns, uid);
inode->i_uid = make_kuid(i_user_ns(inode), uid);
}
static inline void i_gid_write(struct inode *inode, gid_t gid)
{
inode->i_gid = make_kgid(inode->i_sb->s_user_ns, gid);
}
/**
* kuid_into_mnt - map a kuid down into a mnt_userns
* @mnt_userns: user namespace of the relevant mount
* @kuid: kuid to be mapped
*
* Return: @kuid mapped according to @mnt_userns.
* If @kuid has no mapping INVALID_UID is returned.
*/
static inline kuid_t kuid_into_mnt(struct user_namespace *mnt_userns,
kuid_t kuid)
{
return make_kuid(mnt_userns, __kuid_val(kuid));
}
/**
* kgid_into_mnt - map a kgid down into a mnt_userns
* @mnt_userns: user namespace of the relevant mount
* @kgid: kgid to be mapped
*
* Return: @kgid mapped according to @mnt_userns.
* If @kgid has no mapping INVALID_GID is returned.
*/
static inline kgid_t kgid_into_mnt(struct user_namespace *mnt_userns,
kgid_t kgid)
{
return make_kgid(mnt_userns, __kgid_val(kgid));
inode->i_gid = make_kgid(i_user_ns(inode), gid);
}
/**
@@ -1697,7 +1675,7 @@ static inline kgid_t kgid_into_mnt(struct user_namespace *mnt_userns,
static inline kuid_t i_uid_into_mnt(struct user_namespace *mnt_userns,
const struct inode *inode)
{
return kuid_into_mnt(mnt_userns, inode->i_uid);
return mapped_kuid_fs(mnt_userns, i_user_ns(inode), inode->i_uid);
}
/**
@@ -1711,69 +1689,7 @@ static inline kuid_t i_uid_into_mnt(struct user_namespace *mnt_userns,
static inline kgid_t i_gid_into_mnt(struct user_namespace *mnt_userns,
const struct inode *inode)
{
return kgid_into_mnt(mnt_userns, inode->i_gid);
}
/**
* kuid_from_mnt - map a kuid up into a mnt_userns
* @mnt_userns: user namespace of the relevant mount
* @kuid: kuid to be mapped
*
* Return: @kuid mapped up according to @mnt_userns.
* If @kuid has no mapping INVALID_UID is returned.
*/
static inline kuid_t kuid_from_mnt(struct user_namespace *mnt_userns,
kuid_t kuid)
{
return KUIDT_INIT(from_kuid(mnt_userns, kuid));
}
/**
* kgid_from_mnt - map a kgid up into a mnt_userns
* @mnt_userns: user namespace of the relevant mount
* @kgid: kgid to be mapped
*
* Return: @kgid mapped up according to @mnt_userns.
* If @kgid has no mapping INVALID_GID is returned.
*/
static inline kgid_t kgid_from_mnt(struct user_namespace *mnt_userns,
kgid_t kgid)
{
return KGIDT_INIT(from_kgid(mnt_userns, kgid));
}
/**
* mapped_fsuid - return caller's fsuid mapped up into a mnt_userns
* @mnt_userns: user namespace of the relevant mount
*
* Use this helper to initialize a new vfs or filesystem object based on
* the caller's fsuid. A common example is initializing the i_uid field of
* a newly allocated inode triggered by a creation event such as mkdir or
* O_CREAT. Other examples include the allocation of quotas for a specific
* user.
*
* Return: the caller's current fsuid mapped up according to @mnt_userns.
*/
static inline kuid_t mapped_fsuid(struct user_namespace *mnt_userns)
{
return kuid_from_mnt(mnt_userns, current_fsuid());
}
/**
* mapped_fsgid - return caller's fsgid mapped up into a mnt_userns
* @mnt_userns: user namespace of the relevant mount
*
* Use this helper to initialize a new vfs or filesystem object based on
* the caller's fsgid. A common example is initializing the i_gid field of
* a newly allocated inode triggered by a creation event such as mkdir or
* O_CREAT. Other examples include the allocation of quotas for a specific
* user.
*
* Return: the caller's current fsgid mapped up according to @mnt_userns.
*/
static inline kgid_t mapped_fsgid(struct user_namespace *mnt_userns)
{
return kgid_from_mnt(mnt_userns, current_fsgid());
return mapped_kgid_fs(mnt_userns, i_user_ns(inode), inode->i_gid);
}
/**
@@ -1787,7 +1703,7 @@ static inline kgid_t mapped_fsgid(struct user_namespace *mnt_userns)
static inline void inode_fsuid_set(struct inode *inode,
struct user_namespace *mnt_userns)
{
inode->i_uid = mapped_fsuid(mnt_userns);
inode->i_uid = mapped_fsuid(mnt_userns, i_user_ns(inode));
}
/**
@@ -1801,7 +1717,7 @@ static inline void inode_fsuid_set(struct inode *inode,
static inline void inode_fsgid_set(struct inode *inode,
struct user_namespace *mnt_userns)
{
inode->i_gid = mapped_fsgid(mnt_userns);
inode->i_gid = mapped_fsgid(mnt_userns, i_user_ns(inode));
}
/**
@@ -1818,10 +1734,18 @@ static inline void inode_fsgid_set(struct inode *inode,
static inline bool fsuidgid_has_mapping(struct super_block *sb,
struct user_namespace *mnt_userns)
{
struct user_namespace *s_user_ns = sb->s_user_ns;
struct user_namespace *fs_userns = sb->s_user_ns;
kuid_t kuid;
kgid_t kgid;
return kuid_has_mapping(s_user_ns, mapped_fsuid(mnt_userns)) &&
kgid_has_mapping(s_user_ns, mapped_fsgid(mnt_userns));
kuid = mapped_fsuid(mnt_userns, fs_userns);
if (!uid_valid(kuid))
return false;
kgid = mapped_fsgid(mnt_userns, fs_userns);
if (!gid_valid(kgid))
return false;
return kuid_has_mapping(fs_userns, kuid) &&
kgid_has_mapping(fs_userns, kgid);
}
extern struct timespec64 current_time(struct inode *inode);
@@ -2778,6 +2702,21 @@ static inline struct user_namespace *file_mnt_user_ns(struct file *file)
{
return mnt_user_ns(file->f_path.mnt);
}
/**
* is_idmapped_mnt - check whether a mount is mapped
* @mnt: the mount to check
*
* If @mnt has an idmapping attached different from the
* filesystem's idmapping then @mnt is mapped.
*
* Return: true if mount is mapped, false if not.
*/
static inline bool is_idmapped_mnt(const struct vfsmount *mnt)
{
return mnt_user_ns(mnt) != mnt->mnt_sb->s_user_ns;
}
extern long vfs_truncate(const struct path *, loff_t);
int do_truncate(struct user_namespace *, struct dentry *, loff_t start,
unsigned int time_attrs, struct file *filp);

234
include/linux/mnt_idmapping.h Normal file
View File

@@ -0,0 +1,234 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_MNT_IDMAPPING_H
#define _LINUX_MNT_IDMAPPING_H
#include <linux/types.h>
#include <linux/uidgid.h>
struct user_namespace;
/*
* Carries the initial idmapping of 0:0:4294967295 which is an identity
* mapping. This means that {g,u}id 0 is mapped to {g,u}id 0, {g,u}id 1 is
* mapped to {g,u}id 1, [...], {g,u}id 1000 to {g,u}id 1000, [...].
*/
extern struct user_namespace init_user_ns;
/**
* initial_idmapping - check whether this is the initial mapping
* @ns: idmapping to check
*
* Check whether this is the initial mapping, mapping 0 to 0, 1 to 1,
* [...], 1000 to 1000 [...].
*
* Return: true if this is the initial mapping, false if not.
*/
static inline bool initial_idmapping(const struct user_namespace *ns)
{
return ns == &init_user_ns;
}
/**
* no_idmapping - check whether we can skip remapping a kuid/gid
* @mnt_userns: the mount's idmapping
* @fs_userns: the filesystem's idmapping
*
* This function can be used to check whether a remapping between two
* idmappings is required.
* An idmapped mount is a mount that has an idmapping attached to it that
* is different from the filsystem's idmapping and the initial idmapping.
* If the initial mapping is used or the idmapping of the mount and the
* filesystem are identical no remapping is required.
*
* Return: true if remapping can be skipped, false if not.
*/
static inline bool no_idmapping(const struct user_namespace *mnt_userns,
const struct user_namespace *fs_userns)
{
return initial_idmapping(mnt_userns) || mnt_userns == fs_userns;
}
/**
* mapped_kuid_fs - map a filesystem kuid into a mnt_userns
* @mnt_userns: the mount's idmapping
* @fs_userns: the filesystem's idmapping
* @kuid : kuid to be mapped
*
* Take a @kuid and remap it from @fs_userns into @mnt_userns. Use this
* function when preparing a @kuid to be reported to userspace.
*
* If no_idmapping() determines that this is not an idmapped mount we can
* simply return @kuid unchanged.
* If initial_idmapping() tells us that the filesystem is not mounted with an
* idmapping we know the value of @kuid won't change when calling
* from_kuid() so we can simply retrieve the value via __kuid_val()
* directly.
*
* Return: @kuid mapped according to @mnt_userns.
* If @kuid has no mapping in either @mnt_userns or @fs_userns INVALID_UID is
* returned.
*/
static inline kuid_t mapped_kuid_fs(struct user_namespace *mnt_userns,
struct user_namespace *fs_userns,
kuid_t kuid)
{
uid_t uid;
if (no_idmapping(mnt_userns, fs_userns))
return kuid;
if (initial_idmapping(fs_userns))
uid = __kuid_val(kuid);
else
uid = from_kuid(fs_userns, kuid);
if (uid == (uid_t)-1)
return INVALID_UID;
return make_kuid(mnt_userns, uid);
}
/**
* mapped_kgid_fs - map a filesystem kgid into a mnt_userns
* @mnt_userns: the mount's idmapping
* @fs_userns: the filesystem's idmapping
* @kgid : kgid to be mapped
*
* Take a @kgid and remap it from @fs_userns into @mnt_userns. Use this
* function when preparing a @kgid to be reported to userspace.
*
* If no_idmapping() determines that this is not an idmapped mount we can
* simply return @kgid unchanged.
* If initial_idmapping() tells us that the filesystem is not mounted with an
* idmapping we know the value of @kgid won't change when calling
* from_kgid() so we can simply retrieve the value via __kgid_val()
* directly.
*
* Return: @kgid mapped according to @mnt_userns.
* If @kgid has no mapping in either @mnt_userns or @fs_userns INVALID_GID is
* returned.
*/
static inline kgid_t mapped_kgid_fs(struct user_namespace *mnt_userns,
struct user_namespace *fs_userns,
kgid_t kgid)
{
gid_t gid;
if (no_idmapping(mnt_userns, fs_userns))
return kgid;
if (initial_idmapping(fs_userns))
gid = __kgid_val(kgid);
else
gid = from_kgid(fs_userns, kgid);
if (gid == (gid_t)-1)
return INVALID_GID;
return make_kgid(mnt_userns, gid);
}
/**
* mapped_kuid_user - map a user kuid into a mnt_userns
* @mnt_userns: the mount's idmapping
* @fs_userns: the filesystem's idmapping
* @kuid : kuid to be mapped
*
* Use the idmapping of @mnt_userns to remap a @kuid into @fs_userns. Use this
* function when preparing a @kuid to be written to disk or inode.
*
* If no_idmapping() determines that this is not an idmapped mount we can
* simply return @kuid unchanged.
* If initial_idmapping() tells us that the filesystem is not mounted with an
* idmapping we know the value of @kuid won't change when calling
* make_kuid() so we can simply retrieve the value via KUIDT_INIT()
* directly.
*
* Return: @kuid mapped according to @mnt_userns.
* If @kuid has no mapping in either @mnt_userns or @fs_userns INVALID_UID is
* returned.
*/
static inline kuid_t mapped_kuid_user(struct user_namespace *mnt_userns,
struct user_namespace *fs_userns,
kuid_t kuid)
{
uid_t uid;
if (no_idmapping(mnt_userns, fs_userns))
return kuid;
uid = from_kuid(mnt_userns, kuid);
if (uid == (uid_t)-1)
return INVALID_UID;
if (initial_idmapping(fs_userns))
return KUIDT_INIT(uid);
return make_kuid(fs_userns, uid);
}
/**
* mapped_kgid_user - map a user kgid into a mnt_userns
* @mnt_userns: the mount's idmapping
* @fs_userns: the filesystem's idmapping
* @kgid : kgid to be mapped
*
* Use the idmapping of @mnt_userns to remap a @kgid into @fs_userns. Use this
* function when preparing a @kgid to be written to disk or inode.
*
* If no_idmapping() determines that this is not an idmapped mount we can
* simply return @kgid unchanged.
* If initial_idmapping() tells us that the filesystem is not mounted with an
* idmapping we know the value of @kgid won't change when calling
* make_kgid() so we can simply retrieve the value via KGIDT_INIT()
* directly.
*
* Return: @kgid mapped according to @mnt_userns.
* If @kgid has no mapping in either @mnt_userns or @fs_userns INVALID_GID is
* returned.
*/
static inline kgid_t mapped_kgid_user(struct user_namespace *mnt_userns,
struct user_namespace *fs_userns,
kgid_t kgid)
{
gid_t gid;
if (no_idmapping(mnt_userns, fs_userns))
return kgid;
gid = from_kgid(mnt_userns, kgid);
if (gid == (gid_t)-1)
return INVALID_GID;
if (initial_idmapping(fs_userns))
return KGIDT_INIT(gid);
return make_kgid(fs_userns, gid);
}
/**
* mapped_fsuid - return caller's fsuid mapped up into a mnt_userns
* @mnt_userns: the mount's idmapping
* @fs_userns: the filesystem's idmapping
*
* Use this helper to initialize a new vfs or filesystem object based on
* the caller's fsuid. A common example is initializing the i_uid field of
* a newly allocated inode triggered by a creation event such as mkdir or
* O_CREAT. Other examples include the allocation of quotas for a specific
* user.
*
* Return: the caller's current fsuid mapped up according to @mnt_userns.
*/
static inline kuid_t mapped_fsuid(struct user_namespace *mnt_userns,
struct user_namespace *fs_userns)
{
return mapped_kuid_user(mnt_userns, fs_userns, current_fsuid());
}
/**
* mapped_fsgid - return caller's fsgid mapped up into a mnt_userns
* @mnt_userns: the mount's idmapping
* @fs_userns: the filesystem's idmapping
*
* Use this helper to initialize a new vfs or filesystem object based on
* the caller's fsgid. A common example is initializing the i_gid field of
* a newly allocated inode triggered by a creation event such as mkdir or
* O_CREAT. Other examples include the allocation of quotas for a specific
* user.
*
* Return: the caller's current fsgid mapped up according to @mnt_userns.
*/
static inline kgid_t mapped_fsgid(struct user_namespace *mnt_userns,
struct user_namespace *fs_userns)
{
return mapped_kgid_user(mnt_userns, fs_userns, current_fsgid());
}
#endif /* _LINUX_MNT_IDMAPPING_H */

4
include/linux/posix_acl_xattr.h
View File

@@ -34,15 +34,19 @@ posix_acl_xattr_count(size_t size)
#ifdef CONFIG_FS_POSIX_ACL
void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_userns,
struct inode *inode,
void *value, size_t size);
void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_userns,
struct inode *inode,
void *value, size_t size);
#else
static inline void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_userns,
struct inode *inode,
void *value, size_t size)
{
}
static inline void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_userns,
struct inode *inode,
void *value, size_t size)
{
}

1
kernel/time/tick-sched.c
View File

@@ -512,7 +512,6 @@ void __init tick_nohz_full_setup(cpumask_var_t cpumask)
cpumask_copy(tick_nohz_full_mask, cpumask);
tick_nohz_full_running = true;
}
EXPORT_SYMBOL_GPL(tick_nohz_full_setup);
static int tick_nohz_cpu_down(unsigned int cpu)
{

15
security/commoncap.c
View File

@@ -24,6 +24,7 @@
#include <linux/user_namespace.h>
#include <linux/binfmts.h>
#include <linux/personality.h>
#include <linux/mnt_idmapping.h>
/*
* If a non-root user executes a setuid-root binary in
@@ -418,7 +419,7 @@ int cap_inode_getsecurity(struct user_namespace *mnt_userns,
kroot = make_kuid(fs_ns, root);
/* If this is an idmapped mount shift the kuid. */
kroot = kuid_into_mnt(mnt_userns, kroot);
kroot = mapped_kuid_fs(mnt_userns, fs_ns, kroot);
/* If the root kuid maps to a valid uid in current ns, then return
* this as a nscap. */
@@ -488,6 +489,7 @@ out_free:
* @size: size of @ivalue
* @task_ns: user namespace of the caller
* @mnt_userns: user namespace of the mount the inode was found from
* @fs_userns: user namespace of the filesystem
*
* If the inode has been found through an idmapped mount the user namespace of
* the vfsmount must be passed through @mnt_userns. This function will then
@@ -497,7 +499,8 @@ out_free:
*/
static kuid_t rootid_from_xattr(const void *value, size_t size,
struct user_namespace *task_ns,
struct user_namespace *mnt_userns)
struct user_namespace *mnt_userns,
struct user_namespace *fs_userns)
{
const struct vfs_ns_cap_data *nscap = value;
kuid_t rootkid;
@@ -507,7 +510,7 @@ static kuid_t rootid_from_xattr(const void *value, size_t size,
rootid = le32_to_cpu(nscap->rootid);
rootkid = make_kuid(task_ns, rootid);
return kuid_from_mnt(mnt_userns, rootkid);
return mapped_kuid_user(mnt_userns, fs_userns, rootkid);
}
static bool validheader(size_t size, const struct vfs_cap_data *cap)
@@ -553,12 +556,12 @@ int cap_convert_nscap(struct user_namespace *mnt_userns, struct dentry *dentry,
return -EINVAL;
if (!capable_wrt_inode_uidgid(mnt_userns, inode, CAP_SETFCAP))
return -EPERM;
if (size == XATTR_CAPS_SZ_2 && (mnt_userns == &init_user_ns))
if (size == XATTR_CAPS_SZ_2 && (mnt_userns == fs_ns))
if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP))
/* user is privileged, just write the v2 */
return size;
rootid = rootid_from_xattr(*ivalue, size, task_ns, mnt_userns);
rootid = rootid_from_xattr(*ivalue, size, task_ns, mnt_userns, fs_ns);
if (!uid_valid(rootid))
return -EINVAL;
@@ -699,7 +702,7 @@ int get_vfs_caps_from_disk(struct user_namespace *mnt_userns,
/* Limit the caps to the mounter of the filesystem
* or the more limited uid specified in the xattr.
*/
rootkuid = kuid_into_mnt(mnt_userns, rootkuid);
rootkuid = mapped_kuid_fs(mnt_userns, fs_ns, rootkuid);
if (!rootid_owns_currentns(rootkuid))
return -ENODATA;