Linux 6.8 compat: handle mnt_idmap user_namespace change

struct mnt_idmap no longer has a struct user_namespace within it. Work
around this by creating a temporary with the copy of the map we need
taken from the idmap.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Youzhong Yang <yyang@mathworks.com>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Sponsored-by: https://despairlabs.com/sponsor/
Closes #15805
This commit is contained in:
Rob Norris 2024-01-23 21:14:06 +11:00 committed by Brian Behlendorf
parent 7a2e54b7d3
commit 2e6b3c4d94
4 changed files with 88 additions and 5 deletions

View file

@ -23,3 +23,28 @@ AC_DEFUN([ZFS_AC_KERNEL_IDMAP_MNT_API], [
])
])
dnl #
dnl # 6.8 decouples mnt_idmap from user_namespace. This is all internal
dnl # to mnt_idmap so we can't detect it directly, but we detect a related
dnl # change as use that as a signal.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_IDMAP_NO_USERNS], [
ZFS_LINUX_TEST_SRC([idmap_no_userns], [
#include <linux/uidgid.h>
], [
struct uid_gid_map *map = NULL;
map_id_down(map, 0);
])
])
AC_DEFUN([ZFS_AC_KERNEL_IDMAP_NO_USERNS], [
AC_MSG_CHECKING([whether idmapped mounts have a user namespace])
ZFS_LINUX_TEST_RESULT([idmap_no_userns], [
AC_MSG_RESULT([yes])
AC_DEFINE(HAVE_IDMAP_NO_USERNS, 1,
[mnt_idmap does not have user_namespace])
], [
AC_MSG_RESULT([no])
])
])

View file

@ -158,6 +158,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_SRC], [
ZFS_AC_KERNEL_SRC___COPY_FROM_USER_INATOMIC
ZFS_AC_KERNEL_SRC_USER_NS_COMMON_INUM
ZFS_AC_KERNEL_SRC_IDMAP_MNT_API
ZFS_AC_KERNEL_SRC_IDMAP_NO_USERNS
ZFS_AC_KERNEL_SRC_IATTR_VFSID
ZFS_AC_KERNEL_SRC_FILEMAP
ZFS_AC_KERNEL_SRC_WRITEPAGE_T
@ -305,6 +306,7 @@ AC_DEFUN([ZFS_AC_KERNEL_TEST_RESULT], [
ZFS_AC_KERNEL___COPY_FROM_USER_INATOMIC
ZFS_AC_KERNEL_USER_NS_COMMON_INUM
ZFS_AC_KERNEL_IDMAP_MNT_API
ZFS_AC_KERNEL_IDMAP_NO_USERNS
ZFS_AC_KERNEL_IATTR_VFSID
ZFS_AC_KERNEL_FILEMAP
ZFS_AC_KERNEL_WRITEPAGE_T

View file

@ -73,13 +73,25 @@ static inline struct user_namespace *zfs_i_user_ns(struct inode *inode)
static inline boolean_t zfs_no_idmapping(struct user_namespace *mnt_userns,
struct user_namespace *fs_userns)
{
return (zfs_is_init_userns(mnt_userns) || mnt_userns == fs_userns);
return (zfs_is_init_userns(mnt_userns) ||
mnt_userns == fs_userns);
}
static inline uid_t zfs_uid_to_vfsuid(zidmap_t *mnt_userns,
struct user_namespace *fs_userns, uid_t uid)
{
struct user_namespace *owner = idmap_owner(mnt_userns);
struct user_namespace *owner;
#ifdef HAVE_IOPS_CREATE_IDMAP
if (mnt_userns == zfs_init_idmap)
return (uid);
#endif
#ifdef HAVE_IDMAP_NO_USERNS
struct user_namespace ns;
ns.uid_map = mnt_userns->uid_map;
owner = &ns;
#else
owner = idmap_owner(mnt_userns);
#endif
if (zfs_no_idmapping(owner, fs_userns))
return (uid);
if (!zfs_is_init_userns(fs_userns))
@ -92,7 +104,18 @@ static inline uid_t zfs_uid_to_vfsuid(zidmap_t *mnt_userns,
static inline gid_t zfs_gid_to_vfsgid(zidmap_t *mnt_userns,
struct user_namespace *fs_userns, gid_t gid)
{
struct user_namespace *owner = idmap_owner(mnt_userns);
struct user_namespace *owner;
#ifdef HAVE_IOPS_CREATE_IDMAP
if (mnt_userns == zfs_init_idmap)
return (gid);
#endif
#ifdef HAVE_IDMAP_NO_USERNS
struct user_namespace ns;
ns.gid_map = mnt_userns->gid_map;
owner = &ns;
#else
owner = idmap_owner(mnt_userns);
#endif
if (zfs_no_idmapping(owner, fs_userns))
return (gid);
if (!zfs_is_init_userns(fs_userns))
@ -105,7 +128,18 @@ static inline gid_t zfs_gid_to_vfsgid(zidmap_t *mnt_userns,
static inline uid_t zfs_vfsuid_to_uid(zidmap_t *mnt_userns,
struct user_namespace *fs_userns, uid_t uid)
{
struct user_namespace *owner = idmap_owner(mnt_userns);
struct user_namespace *owner;
#ifdef HAVE_IOPS_CREATE_IDMAP
if (mnt_userns == zfs_init_idmap)
return (uid);
#endif
#ifdef HAVE_IDMAP_NO_USERNS
struct user_namespace ns;
ns.uid_map = mnt_userns->uid_map;
owner = &ns;
#else
owner = idmap_owner(mnt_userns);
#endif
if (zfs_no_idmapping(owner, fs_userns))
return (uid);
uid = from_kuid(owner, KUIDT_INIT(uid));
@ -119,7 +153,18 @@ static inline uid_t zfs_vfsuid_to_uid(zidmap_t *mnt_userns,
static inline gid_t zfs_vfsgid_to_gid(zidmap_t *mnt_userns,
struct user_namespace *fs_userns, gid_t gid)
{
struct user_namespace *owner = idmap_owner(mnt_userns);
struct user_namespace *owner;
#ifdef HAVE_IOPS_CREATE_IDMAP
if (mnt_userns == zfs_init_idmap)
return (gid);
#endif
#ifdef HAVE_IDMAP_NO_USERNS
struct user_namespace ns;
ns.gid_map = mnt_userns->gid_map;
owner = &ns;
#else
owner = idmap_owner(mnt_userns);
#endif
if (zfs_no_idmapping(owner, fs_userns))
return (gid);
gid = from_kgid(owner, KGIDT_INIT(gid));

View file

@ -57,12 +57,23 @@ typedef int minor_t;
struct user_namespace;
#ifdef HAVE_IOPS_CREATE_IDMAP
#include <linux/refcount.h>
#ifdef HAVE_IDMAP_NO_USERNS
#include <linux/user_namespace.h>
struct mnt_idmap {
struct uid_gid_map uid_map;
struct uid_gid_map gid_map;
refcount_t count;
};
typedef struct mnt_idmap zidmap_t;
#define idmap_owner(p) (NULL)
#else
struct mnt_idmap {
struct user_namespace *owner;
refcount_t count;
};
typedef struct mnt_idmap zidmap_t;
#define idmap_owner(p) (((struct mnt_idmap *)p)->owner)
#endif
#else
typedef struct user_namespace zidmap_t;
#define idmap_owner(p) ((struct user_namespace *)p)