/src/util-linux/include/mountutils.h

Source
/*
 * No copyright is claimed.  This code is in the public domain; do with
 * it what you wish.
 */
#ifndef UTIL_LINUX_MOUNTUTILS_H
#define UTIL_LINUX_MOUNTUTILS_H

#ifdef HAVE_LINUX_MOUNT_H
#include <linux/mount.h>
#include <linux/unistd.h>
#include <sys/syscall.h>
#include <inttypes.h>

/*
 * File descriptors based mount API
 */
#ifdef HAVE_MOUNTFD_API

/* Accepted by both open_tree() and mount_setattr(). */
#ifndef AT_RECURSIVE
# define AT_RECURSIVE 0x8000
#endif

#ifndef OPEN_TREE_CLONE
# define OPEN_TREE_CLONE 1
#endif

#ifndef OPEN_TREE_CLOEXEC
# define OPEN_TREE_CLOEXEC O_CLOEXEC
#endif

#if !defined(HAVE_OPEN_TREE) && defined(SYS_open_tree)
static inline int open_tree(int dfd, const char *filename, unsigned int flags)
{
  return syscall(SYS_open_tree, dfd, filename, flags);
}
#endif

#ifndef MOVE_MOUNT_F_SYMLINKS
# define MOVE_MOUNT_F_SYMLINKS   0x00000001 /* Follow symlinks on from path */
#endif

#ifndef MOVE_MOUNT_F_AUTOMOUNTS
# define MOVE_MOUNT_F_AUTOMOUNTS 0x00000002 /* Follow automounts on from path */
#endif

#ifndef MOVE_MOUNT_F_EMPTY_PATH
# define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 /* Empty from path permitted */
#endif

#ifndef MOVE_MOUNT_T_SYMLINKS
# define MOVE_MOUNT_T_SYMLINKS   0x00000010 /* Follow symlinks on to path */
#endif

#ifndef MOVE_MOUNT_T_AUTOMOUNTS
# define MOVE_MOUNT_T_AUTOMOUNTS 0x00000020 /* Follow automounts on to path */
#endif

#ifndef MOVE_MOUNT_T_EMPTY_PATH
# define MOVE_MOUNT_T_EMPTY_PATH 0x00000040 /* Empty to path permitted */
#endif

#ifndef MOVE_MOUNT_SET_GROUP
# define MOVE_MOUNT_SET_GROUP    0x00000100 /* Set sharing group instead */
#endif

#ifndef MOVE_MOUNT_BENEATH
# define MOVE_MOUNT_BENEATH      0x00000200 /* Mount beneath top mount */
#endif

#ifndef MOVE_MOUNT__MASK
# define MOVE_MOUNT__MASK        0x00000377
#endif

#if !defined(HAVE_MOVE_MOUNT) && defined(SYS_move_mount)
static inline int move_mount(int from_dfd, const char *from_pathname, int to_dfd,
           const char *to_pathname, unsigned int flags)
{
  return syscall(SYS_move_mount, from_dfd, from_pathname, to_dfd,
           to_pathname, flags);
}
#endif

#ifndef MOUNT_ATTR_RDONLY
# define MOUNT_ATTR_RDONLY 0x00000001
#endif

#ifndef MOUNT_ATTR_NOSUID
# define MOUNT_ATTR_NOSUID 0x00000002
#endif

#ifndef MOUNT_ATTR_NODEV
# define MOUNT_ATTR_NODEV 0x00000004
#endif

#ifndef MOUNT_ATTR_NOEXEC
# define MOUNT_ATTR_NOEXEC 0x00000008
#endif

#ifndef MOUNT_ATTR__ATIME
# define MOUNT_ATTR__ATIME 0x00000070
#endif

#ifndef MOUNT_ATTR_RELATIME
# define MOUNT_ATTR_RELATIME 0x00000000
#endif

#ifndef MOUNT_ATTR_NOATIME
# define MOUNT_ATTR_NOATIME 0x00000010
#endif

#ifndef MOUNT_ATTR_STRICTATIME
# define MOUNT_ATTR_STRICTATIME 0x00000020
#endif

#ifndef MOUNT_ATTR_NODIRATIME
# define MOUNT_ATTR_NODIRATIME 0x00000080
#endif

#ifndef MOUNT_ATTR_IDMAP
# define MOUNT_ATTR_IDMAP 0x00100000
#endif

#ifndef MOUNT_ATTR_NOSYMFOLLOW
# define MOUNT_ATTR_NOSYMFOLLOW 0x00200000
#endif

#ifndef HAVE_STRUCT_MOUNT_ATTR
# ifndef MOUNT_ATTR_SIZE_VER0 /* For case mount.h comes from a place invisible for autotools/meson */
struct mount_attr {
  uint64_t attr_set;
  uint64_t attr_clr;
  uint64_t propagation;
  uint64_t userns_fd;
};
# endif
#endif

#if !defined(HAVE_MOUNT_SETATTR) && defined(SYS_mount_setattr)
static inline int mount_setattr(int dfd, const char *path, unsigned int flags,
        struct mount_attr *attr, size_t size)
{
  return syscall(SYS_mount_setattr, dfd, path, flags, attr, size);
}
#endif

#ifndef HAVE_ENUM_FSCONFIG_COMMAND
# ifndef FSOPEN_CLOEXEC /* For case mount.h comes from a place invisible for autotools/meson */
enum fsconfig_command {
  FSCONFIG_SET_FLAG       = 0,    /* Set parameter, supplying no value */
#  define FSCONFIG_SET_FLAG FSCONFIG_SET_FLAG
  FSCONFIG_SET_STRING     = 1,    /* Set parameter, supplying a string value */
#  define FSCONFIG_SET_STRING FSCONFIG_SET_STRING
  FSCONFIG_SET_BINARY     = 2,    /* Set parameter, supplying a binary blob value */
#  define FSCONFIG_SET_BINARY FSCONFIG_SET_BINARY
  FSCONFIG_SET_PATH       = 3,    /* Set parameter, supplying an object by path */
#  define FSCONFIG_SET_PATH FSCONFIG_SET_PATH
  FSCONFIG_SET_PATH_EMPTY = 4,    /* Set parameter, supplying an object by (empty) path */
#  define FSCONFIG_SET_PATH_EMPTY FSCONFIG_SET_PATH_EMPTY
  FSCONFIG_SET_FD         = 5,    /* Set parameter, supplying an object by fd */
#  define FSCONFIG_SET_FD FSCONFIG_SET_FD
  FSCONFIG_CMD_CREATE     = 6,    /* Invoke superblock creation */
#  define FSCONFIG_CMD_CREATE FSCONFIG_CMD_CREATE
  FSCONFIG_CMD_RECONFIGURE = 7,   /* Invoke superblock reconfiguration */
#  define FSCONFIG_CMD_RECONFIGURE FSCONFIG_CMD_RECONFIGURE
  FSCONFIG_CMD_CREATE_EXCL = 8,    /* Create new superblock, fail if reusing existing superblock */
# define FSCONFIG_CMD_CREATE_EXCL FSCONFIG_CMD_CREATE_EXCL
};
# endif /* !FSOPEN_CLOEXEC */
#endif /*!HAVE_ENUM_FSCONFIG_COMMAND */

/*
 * Fallbacks for incomplete enum fsconfig_command in system headrs
 */
#ifndef FSCONFIG_CMD_CREATE_EXCL
# define FSCONFIG_CMD_CREATE_EXCL 8   /* since kernel 6.6 */
#endif

#if !defined(HAVE_FSCONFIG) && defined(SYS_fsconfig)
static inline int fsconfig(int fd, unsigned int cmd, const char *key,
                    const void *value, int aux)
{
        return syscall(SYS_fsconfig, fd, cmd, key, value, aux);
}
#endif

#ifndef FSOPEN_CLOEXEC
# define FSOPEN_CLOEXEC          0x00000001
#endif

#if !defined(HAVE_FSOPEN) && defined(SYS_fsopen)
static inline int fsopen(const char *fsname, unsigned int flags)
{
        return syscall(SYS_fsopen, fsname, flags);
}
#endif

#ifndef FSMOUNT_CLOEXEC
# define FSMOUNT_CLOEXEC         0x00000001
#endif

#if !defined(HAVE_FSMOUNT) && defined(SYS_fsmount)
static inline int fsmount(int fd, unsigned int flags, unsigned int mount_attrs)
{
        return syscall(SYS_fsmount, fd, flags, mount_attrs);
}
#endif

#ifndef FSPICK_CLOEXEC
# define FSPICK_CLOEXEC          0x00000001
#endif

#ifndef FSPICK_SYMLINK_NOFOLLOW
# define FSPICK_SYMLINK_NOFOLLOW 0x00000002
#endif

#ifndef FSPICK_NO_AUTOMOUNT
# define FSPICK_NO_AUTOMOUNT     0x00000004
#endif

#ifdef FSPICK_EMPTY_PATH
# define FSPICK_EMPTY_PATH       0x00000008
#endif

#if !defined(HAVE_FSPICK) && defined(SYS_fspick)
static inline int fspick(int dfd, const char *pathname, unsigned int flags)
{
        return syscall(SYS_fspick, dfd, pathname, flags);
}
#endif

#endif /* HAVE_MOUNTFD_API */

/*
 * statmount() and listmount()
 */
#ifdef HAVE_STATMOUNT_API

#ifndef MNT_ID_REQ_SIZE_VER0
# define MNT_ID_REQ_SIZE_VER0    24 /* sizeof first published struct */
#endif
#ifndef MNT_ID_REQ_SIZE_VER1
# define MNT_ID_REQ_SIZE_VER1    32 /* sizeof second published struct */
#endif

/*
 * The structs mnt_id_req and statmount may differ between kernel versions, so
 * we must ensure that the structs contain everything we need. For now (during
 * development), it seems best to define local copies of the structs to avoid
 * relying on installed kernel headers and to avoid a storm of #ifdefs.
 */

/*
 * listmount() and statmount() request
 */
struct ul_mnt_id_req {
  uint32_t size;
  uint32_t spare;
  uint64_t mnt_id;
  uint64_t param;
  uint64_t mnt_ns_id;
};

/*
 * Please note that due to the variable length of the statmount buffer, the
 * struct cannot be versioned by size (like struct mnt_id_req).
 */
struct ul_statmount {
  uint32_t size;            /* Total size, including strings */
  uint32_t mnt_opts;        /* [str] Mount options of the mount */
  uint64_t mask;            /* What results were written */
  uint32_t sb_dev_major;    /* Device ID */
  uint32_t sb_dev_minor;
  uint64_t sb_magic;        /* ..._SUPER_MAGIC */
  uint32_t sb_flags;        /* SB_{RDONLY,SYNCHRONOUS,DIRSYNC,LAZYTIME} */
  uint32_t fs_type;         /* [str] Filesystem type */
  uint64_t mnt_id;          /* Unique ID of mount */
  uint64_t mnt_parent_id;   /* Unique ID of parent (for root == mnt_id) */
  uint32_t mnt_id_old;      /* Reused IDs used in proc/.../mountinfo */
  uint32_t mnt_parent_id_old;
  uint64_t mnt_attr;        /* MOUNT_ATTR_... */
  uint64_t mnt_propagation; /* MS_{SHARED,SLAVE,PRIVATE,UNBINDABLE} */
  uint64_t mnt_peer_group;  /* ID of shared peer group */
  uint64_t mnt_master;      /* Mount receives propagation from this ID */
  uint64_t propagate_from;  /* Propagation from in current namespace */
  uint32_t mnt_root;        /* [str] Root of mount relative to root of fs */
  uint32_t mnt_point;       /* [str] Mountpoint relative to current root */
  uint64_t mnt_ns_id;       /* ID of the mount namespace */
  uint32_t fs_subtype;      /* [str] Subtype of fs_type (if any) */
  uint32_t sb_source;       /* [str] Source string of the mount */
  uint32_t opt_num;         /* Number of fs options */
  uint32_t opt_array;       /* [str] Array of nul terminated fs options */
  uint32_t opt_sec_num;     /* Number of security options */
  uint32_t opt_sec_array;   /* [str] Array of nul terminated security options */
  uint64_t supported_mask;  /* Mask flags that this kernel supports */
  uint32_t mnt_uidmap_num;  /* Number of uid mappings */
  uint32_t mnt_uidmap;      /* [str] Array of uid mappings (as seen from callers namespace) */
  uint32_t mnt_gidmap_num;  /* Number of gid mappings */
  uint32_t mnt_gidmap;      /* [str] Array of gid mappings (as seen from callers namespace) */
  uint64_t __spare2[43];
  char str[];               /* Variable size part containing strings */
};

/* sb_flags (defined in kernel include/linux/fs.h) */
#ifndef SB_RDONLY
# define SB_RDONLY       BIT(0)   /* Mount read-only */
# define SB_NOSUID       BIT(1)   /* Ignore suid and sgid bits */
# define SB_NODEV        BIT(2)   /* Disallow access to device special files */
# define SB_NOEXEC       BIT(3)   /* Disallow program execution */
# define SB_SYNCHRONOUS  BIT(4)   /* Writes are synced at once */
# define SB_MANDLOCK     BIT(6)   /* Allow mandatory locks on an FS */
# define SB_DIRSYNC      BIT(7)   /* Directory modifications are synchronous */
# define SB_NOATIME      BIT(10)  /* Do not update access times. */
# define SB_NODIRATIME   BIT(11)  /* Do not update directory access times */
# define SB_SILENT       BIT(15)
# define SB_POSIXACL     BIT(16)  /* Supports POSIX ACLs */
# define SB_INLINECRYPT  BIT(17)  /* Use blk-crypto for encrypted files */
# define SB_KERNMOUNT    BIT(22)  /* this is a kern_mount call */
# define SB_I_VERSION    BIT(23)  /* Update inode I_version field */
# define SB_LAZYTIME     BIT(25)  /* Update the on-disk [acm]times lazily */
#endif

/*
 * @mask bits for statmount(2)
 */
#ifndef STATMOUNT_SB_BASIC
# define STATMOUNT_SB_BASIC            0x00000001U   /* Want/got sb_... */
#endif
#ifndef STATMOUNT_MNT_BASIC
# define STATMOUNT_MNT_BASIC           0x00000002U   /* Want/got mnt_... */
#endif
#ifndef STATMOUNT_PROPAGATE_FROM
# define STATMOUNT_PROPAGATE_FROM      0x00000004U   /* Want/got propagate_from */
#endif
#ifndef STATMOUNT_MNT_ROOT
# define STATMOUNT_MNT_ROOT            0x00000008U   /* Want/got mnt_root  */
#endif
#ifndef STATMOUNT_MNT_POINT
# define STATMOUNT_MNT_POINT           0x00000010U   /* Want/got mnt_point */
#endif
#ifndef STATMOUNT_FS_TYPE
# define STATMOUNT_FS_TYPE             0x00000020U   /* Want/got fs_type */
#endif
#ifndef STATMOUNT_MNT_NS_ID
# define STATMOUNT_MNT_NS_ID           0x00000040U   /* Want/got mnt_ns_id */
#endif
#ifndef STATMOUNT_MNT_OPTS
# define STATMOUNT_MNT_OPTS            0x00000080U   /* Want/got mnt_opts */
#endif
#ifndef STATMOUNT_FS_SUBTYPE
# define STATMOUNT_FS_SUBTYPE          0x00000100U   /* Want/got fs_subtype */
#endif
#ifndef STATMOUNT_SB_SOURCE
# define STATMOUNT_SB_SOURCE           0x00000200U   /* Want/got sb_source */
#endif
#ifndef STATMOUNT_OPT_ARRAY
# define STATMOUNT_OPT_ARRAY           0x00000400U   /* Want/got opt_... */
#endif
#ifndef STATMOUNT_OPT_SEC_ARRAY
# define STATMOUNT_OPT_SEC_ARRAY       0x00000800U   /* Want/got opt_sec... */
#endif
#ifndef STATMOUNT_SUPPORTED_MASK
# define STATMOUNT_SUPPORTED_MASK      0x00001000U   /* Want/got supported mask flags */
#endif
#ifndef STATMOUNT_MNT_UIDMAP
# define STATMOUNT_MNT_UIDMAP          0x00002000U   /* Want/got uidmap... */
#endif
#ifndef STATMOUNT_MNT_GIDMAP
# define STATMOUNT_MNT_GIDMAP          0x00004000U   /* Want/got gidmap... */
#endif
/*
 * Special @mnt_id values that can be passed to listmount
 */
#ifndef LSMT_ROOT
# define LSMT_ROOT              0xffffffffffffffff    /* root mount */
#endif

#ifndef LISTMOUNT_REVERSE
# define LISTMOUNT_REVERSE      BIT(0)               /* List later mounts first */
#endif

/* Don't use this "raw" version. See ul_statmount() below. */
#if defined(SYS_statmount)
static inline int ul_statmount_syscall(uint64_t mnt_id,
      uint64_t ns_id,
      uint64_t mask,
      struct ul_statmount *buf,
      size_t bufsize, unsigned int flags)
{
       struct ul_mnt_id_req req = {
    .size = MNT_ID_REQ_SIZE_VER1,
    .mnt_id = mnt_id,
    .param = mask,
    .mnt_ns_id = ns_id
       };

       return syscall(SYS_statmount, &req, buf, bufsize, flags);
}

static inline int has_statmount(void)
{
  errno = 0;

  if (ul_statmount_syscall(0, 0, 0, NULL, 0, 0) < 0 && errno == ENOSYS)
    return 0;
  return 1;
}

/* This is a version of statmount() that reallocates @buf to be large enough to
 * store data for the requested @id. This function never deallocates; it is the
 * caller's responsibility.
 */
static inline int ul_statmount(uint64_t id,
      uint64_t ns_id,
      uint64_t mask,
      struct ul_statmount **buf,
      size_t *bufsiz,
      unsigned int flags)
{
  size_t sz;
  int rc = 0;

  if (!buf || !bufsiz)
    return -EINVAL;

  sz = *bufsiz;
  if (!sz)
    sz = 32 * 1024;

  do {
    if (sz > *bufsiz) {
      struct ul_statmount *tmp = realloc(*buf, sz);
      if (!tmp)
        return -ENOMEM;
      *buf = tmp;
      *bufsiz = sz;
    }

    errno = 0;
    rc = ul_statmount_syscall(id, ns_id, mask, *buf, *bufsiz, flags);
    if (!rc)
      break;
    if (errno != EOVERFLOW)
      break;
    if (sz >= SIZE_MAX / 2)
      break;
    sz <<= 1;
  } while (rc);

  return rc;
}
#endif /* SYS_statmount */


#if defined(SYS_listmount)
static inline ssize_t ul_listmount(uint64_t mnt_id,
      uint64_t ns_id,
      uint64_t last_mnt_id,
      uint64_t list[], size_t num,
      unsigned int flags)
{
       struct ul_mnt_id_req req = {
    .size = MNT_ID_REQ_SIZE_VER1,
    .mnt_id = mnt_id,
    .param = last_mnt_id,
    .mnt_ns_id = ns_id
       };

       return syscall(SYS_listmount, &req, list, num, flags);
}

static inline int has_listmount(void)
{
  uint64_t dummy;

  errno = 0;

  if (ul_listmount(LSMT_ROOT, 0, 0, &dummy, 1, LISTMOUNT_REVERSE) != 1)
    return 0;
  return 1;
}
#endif

#endif /* HAVE_STATMOUNT_API */
#endif /* HAVE_LINUX_MOUNT_H */

/*
 * Default NTFS mount type (used by libmount and libblkid)
 */
#ifndef CONFIG_UL_NTFS_MOUNTTYPE
# define CONFIG_UL_NTFS_MOUNTTYPE "ntfs3"
#endif

/*
 * Convert FS-type (as provided by libblkid or udev) to the preferred
 * kernel FS driver (type used to mount the FS).
 *
 * This is a temporary solution; the final solution should be based on config
 * files like /etc/mount/fs.d/<name> (from lib/configs.c) and managed by
 * libmount.
 */
static inline const char *ul_fstype_to_mounttype(const char *fstype)
{
  if (!fstype)
    return NULL;

  if (strcmp(fstype, "ntfs") == 0)
    return CONFIG_UL_NTFS_MOUNTTYPE;

  return NULL;
}
#endif /* UTIL_LINUX_MOUNTUTILS_H */

Coverage Report

Created: 2026-06-10 06:32

Line	Count	Source
1		/*
2		* No copyright is claimed. This code is in the public domain; do with
3		* it what you wish.
4		*/
5		#ifndef UTIL_LINUX_MOUNTUTILS_H
6		#define UTIL_LINUX_MOUNTUTILS_H
7
8		#ifdef HAVE_LINUX_MOUNT_H
9		#include <linux/mount.h>
10		#include <linux/unistd.h>
11		#include <sys/syscall.h>
12		#include <inttypes.h>
13
14		/*
15		* File descriptors based mount API
16		*/
17		#ifdef HAVE_MOUNTFD_API
18
19		/* Accepted by both open_tree() and mount_setattr(). */
20		#ifndef AT_RECURSIVE
21		# define AT_RECURSIVE 0x8000
22		#endif
23
24		#ifndef OPEN_TREE_CLONE
25		# define OPEN_TREE_CLONE 1
26		#endif
27
28		#ifndef OPEN_TREE_CLOEXEC
29		# define OPEN_TREE_CLOEXEC O_CLOEXEC
30		#endif
31
32		#if !defined(HAVE_OPEN_TREE) && defined(SYS_open_tree)
33		static inline int open_tree(int dfd, const char *filename, unsigned int flags)
34		{
35		return syscall(SYS_open_tree, dfd, filename, flags);
36		}
37		#endif
38
39		#ifndef MOVE_MOUNT_F_SYMLINKS
40		# define MOVE_MOUNT_F_SYMLINKS 0x00000001 /* Follow symlinks on from path */
41		#endif
42
43		#ifndef MOVE_MOUNT_F_AUTOMOUNTS
44		# define MOVE_MOUNT_F_AUTOMOUNTS 0x00000002 /* Follow automounts on from path */
45		#endif
46
47		#ifndef MOVE_MOUNT_F_EMPTY_PATH
48		# define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 /* Empty from path permitted */
49		#endif
50
51		#ifndef MOVE_MOUNT_T_SYMLINKS
52		# define MOVE_MOUNT_T_SYMLINKS 0x00000010 /* Follow symlinks on to path */
53		#endif
54
55		#ifndef MOVE_MOUNT_T_AUTOMOUNTS
56		# define MOVE_MOUNT_T_AUTOMOUNTS 0x00000020 /* Follow automounts on to path */
57		#endif
58
59		#ifndef MOVE_MOUNT_T_EMPTY_PATH
60		# define MOVE_MOUNT_T_EMPTY_PATH 0x00000040 /* Empty to path permitted */
61		#endif
62
63		#ifndef MOVE_MOUNT_SET_GROUP
64		# define MOVE_MOUNT_SET_GROUP 0x00000100 /* Set sharing group instead */
65		#endif
66
67		#ifndef MOVE_MOUNT_BENEATH
68		# define MOVE_MOUNT_BENEATH 0x00000200 /* Mount beneath top mount */
69		#endif
70
71		#ifndef MOVE_MOUNT__MASK
72		# define MOVE_MOUNT__MASK 0x00000377
73		#endif
74
75		#if !defined(HAVE_MOVE_MOUNT) && defined(SYS_move_mount)
76		static inline int move_mount(int from_dfd, const char *from_pathname, int to_dfd,
77		const char *to_pathname, unsigned int flags)
78		{
79		return syscall(SYS_move_mount, from_dfd, from_pathname, to_dfd,
80		to_pathname, flags);
81		}
82		#endif
83
84		#ifndef MOUNT_ATTR_RDONLY
85		# define MOUNT_ATTR_RDONLY 0x00000001
86		#endif
87
88		#ifndef MOUNT_ATTR_NOSUID
89		# define MOUNT_ATTR_NOSUID 0x00000002
90		#endif
91
92		#ifndef MOUNT_ATTR_NODEV
93		# define MOUNT_ATTR_NODEV 0x00000004
94		#endif
95
96		#ifndef MOUNT_ATTR_NOEXEC
97		# define MOUNT_ATTR_NOEXEC 0x00000008
98		#endif
99
100		#ifndef MOUNT_ATTR__ATIME
101		# define MOUNT_ATTR__ATIME 0x00000070
102		#endif
103
104		#ifndef MOUNT_ATTR_RELATIME
105		# define MOUNT_ATTR_RELATIME 0x00000000
106		#endif
107
108		#ifndef MOUNT_ATTR_NOATIME
109		# define MOUNT_ATTR_NOATIME 0x00000010
110		#endif
111
112		#ifndef MOUNT_ATTR_STRICTATIME
113		# define MOUNT_ATTR_STRICTATIME 0x00000020
114		#endif
115
116		#ifndef MOUNT_ATTR_NODIRATIME
117		# define MOUNT_ATTR_NODIRATIME 0x00000080
118		#endif
119
120		#ifndef MOUNT_ATTR_IDMAP
121		# define MOUNT_ATTR_IDMAP 0x00100000
122		#endif
123
124		#ifndef MOUNT_ATTR_NOSYMFOLLOW
125		# define MOUNT_ATTR_NOSYMFOLLOW 0x00200000
126		#endif
127
128		#ifndef HAVE_STRUCT_MOUNT_ATTR
129		# ifndef MOUNT_ATTR_SIZE_VER0 /* For case mount.h comes from a place invisible for autotools/meson */
130		struct mount_attr {
131		uint64_t attr_set;
132		uint64_t attr_clr;
133		uint64_t propagation;
134		uint64_t userns_fd;
135		};
136		# endif
137		#endif
138
139		#if !defined(HAVE_MOUNT_SETATTR) && defined(SYS_mount_setattr)
140		static inline int mount_setattr(int dfd, const char *path, unsigned int flags,
141		struct mount_attr *attr, size_t size)
142		{
143		return syscall(SYS_mount_setattr, dfd, path, flags, attr, size);
144		}
145		#endif
146
147		#ifndef HAVE_ENUM_FSCONFIG_COMMAND
148		# ifndef FSOPEN_CLOEXEC /* For case mount.h comes from a place invisible for autotools/meson */
149		enum fsconfig_command {
150		FSCONFIG_SET_FLAG = 0, /* Set parameter, supplying no value */
151		# define FSCONFIG_SET_FLAG FSCONFIG_SET_FLAG
152		FSCONFIG_SET_STRING = 1, /* Set parameter, supplying a string value */
153		# define FSCONFIG_SET_STRING FSCONFIG_SET_STRING
154		FSCONFIG_SET_BINARY = 2, /* Set parameter, supplying a binary blob value */
155		# define FSCONFIG_SET_BINARY FSCONFIG_SET_BINARY
156		FSCONFIG_SET_PATH = 3, /* Set parameter, supplying an object by path */
157		# define FSCONFIG_SET_PATH FSCONFIG_SET_PATH
158		FSCONFIG_SET_PATH_EMPTY = 4, /* Set parameter, supplying an object by (empty) path */
159		# define FSCONFIG_SET_PATH_EMPTY FSCONFIG_SET_PATH_EMPTY
160		FSCONFIG_SET_FD = 5, /* Set parameter, supplying an object by fd */
161		# define FSCONFIG_SET_FD FSCONFIG_SET_FD
162		FSCONFIG_CMD_CREATE = 6, /* Invoke superblock creation */
163		# define FSCONFIG_CMD_CREATE FSCONFIG_CMD_CREATE
164		FSCONFIG_CMD_RECONFIGURE = 7, /* Invoke superblock reconfiguration */
165		# define FSCONFIG_CMD_RECONFIGURE FSCONFIG_CMD_RECONFIGURE
166		FSCONFIG_CMD_CREATE_EXCL = 8, /* Create new superblock, fail if reusing existing superblock */
167		# define FSCONFIG_CMD_CREATE_EXCL FSCONFIG_CMD_CREATE_EXCL
168		};
169		# endif /* !FSOPEN_CLOEXEC */
170		#endif /!HAVE_ENUM_FSCONFIG_COMMAND /
171
172		/*
173		* Fallbacks for incomplete enum fsconfig_command in system headrs
174		*/
175		#ifndef FSCONFIG_CMD_CREATE_EXCL
176		# define FSCONFIG_CMD_CREATE_EXCL 8 /* since kernel 6.6 */
177		#endif
178
179		#if !defined(HAVE_FSCONFIG) && defined(SYS_fsconfig)
180		static inline int fsconfig(int fd, unsigned int cmd, const char *key,
181		const void *value, int aux)
182		{
183		return syscall(SYS_fsconfig, fd, cmd, key, value, aux);
184		}
185		#endif
186
187		#ifndef FSOPEN_CLOEXEC
188		# define FSOPEN_CLOEXEC 0x00000001
189		#endif
190
191		#if !defined(HAVE_FSOPEN) && defined(SYS_fsopen)
192		static inline int fsopen(const char *fsname, unsigned int flags)
193		{
194		return syscall(SYS_fsopen, fsname, flags);
195		}
196		#endif
197
198		#ifndef FSMOUNT_CLOEXEC
199		# define FSMOUNT_CLOEXEC 0x00000001
200		#endif
201
202		#if !defined(HAVE_FSMOUNT) && defined(SYS_fsmount)
203		static inline int fsmount(int fd, unsigned int flags, unsigned int mount_attrs)
204		{
205		return syscall(SYS_fsmount, fd, flags, mount_attrs);
206		}
207		#endif
208
209		#ifndef FSPICK_CLOEXEC
210		# define FSPICK_CLOEXEC 0x00000001
211		#endif
212
213		#ifndef FSPICK_SYMLINK_NOFOLLOW
214		# define FSPICK_SYMLINK_NOFOLLOW 0x00000002
215		#endif
216
217		#ifndef FSPICK_NO_AUTOMOUNT
218		# define FSPICK_NO_AUTOMOUNT 0x00000004
219		#endif
220
221		#ifdef FSPICK_EMPTY_PATH
222		# define FSPICK_EMPTY_PATH 0x00000008
223		#endif
224
225		#if !defined(HAVE_FSPICK) && defined(SYS_fspick)
226		static inline int fspick(int dfd, const char *pathname, unsigned int flags)
227		{
228		return syscall(SYS_fspick, dfd, pathname, flags);
229		}
230		#endif
231
232		#endif /* HAVE_MOUNTFD_API */
233
234		/*
235		* statmount() and listmount()
236		*/
237		#ifdef HAVE_STATMOUNT_API
238
239		#ifndef MNT_ID_REQ_SIZE_VER0
240		# define MNT_ID_REQ_SIZE_VER0 24 /* sizeof first published struct */
241		#endif
242		#ifndef MNT_ID_REQ_SIZE_VER1
243		# define MNT_ID_REQ_SIZE_VER1 32 /* sizeof second published struct */
244		#endif
245
246		/*
247		* The structs mnt_id_req and statmount may differ between kernel versions, so
248		* we must ensure that the structs contain everything we need. For now (during
249		* development), it seems best to define local copies of the structs to avoid
250		* relying on installed kernel headers and to avoid a storm of #ifdefs.
251		*/
252
253		/*
254		* listmount() and statmount() request
255		*/
256		struct ul_mnt_id_req {
257		uint32_t size;
258		uint32_t spare;
259		uint64_t mnt_id;
260		uint64_t param;
261		uint64_t mnt_ns_id;
262		};
263
264		/*
265		* Please note that due to the variable length of the statmount buffer, the
266		* struct cannot be versioned by size (like struct mnt_id_req).
267		*/
268		struct ul_statmount {
269		uint32_t size; /* Total size, including strings */
270		uint32_t mnt_opts; /* [str] Mount options of the mount */
271		uint64_t mask; /* What results were written */
272		uint32_t sb_dev_major; /* Device ID */
273		uint32_t sb_dev_minor;
274		uint64_t sb_magic; /* ..._SUPER_MAGIC */
275		uint32_t sb_flags; /* SB_{RDONLY,SYNCHRONOUS,DIRSYNC,LAZYTIME} */
276		uint32_t fs_type; /* [str] Filesystem type */
277		uint64_t mnt_id; /* Unique ID of mount */
278		uint64_t mnt_parent_id; /* Unique ID of parent (for root == mnt_id) */
279		uint32_t mnt_id_old; /* Reused IDs used in proc/.../mountinfo */
280		uint32_t mnt_parent_id_old;
281		uint64_t mnt_attr; /* MOUNT_ATTR_... */
282		uint64_t mnt_propagation; /* MS_{SHARED,SLAVE,PRIVATE,UNBINDABLE} */
283		uint64_t mnt_peer_group; /* ID of shared peer group */
284		uint64_t mnt_master; /* Mount receives propagation from this ID */
285		uint64_t propagate_from; /* Propagation from in current namespace */
286		uint32_t mnt_root; /* [str] Root of mount relative to root of fs */
287		uint32_t mnt_point; /* [str] Mountpoint relative to current root */
288		uint64_t mnt_ns_id; /* ID of the mount namespace */
289		uint32_t fs_subtype; /* [str] Subtype of fs_type (if any) */
290		uint32_t sb_source; /* [str] Source string of the mount */
291		uint32_t opt_num; /* Number of fs options */
292		uint32_t opt_array; /* [str] Array of nul terminated fs options */
293		uint32_t opt_sec_num; /* Number of security options */
294		uint32_t opt_sec_array; /* [str] Array of nul terminated security options */
295		uint64_t supported_mask; /* Mask flags that this kernel supports */
296		uint32_t mnt_uidmap_num; /* Number of uid mappings */
297		uint32_t mnt_uidmap; /* [str] Array of uid mappings (as seen from callers namespace) */
298		uint32_t mnt_gidmap_num; /* Number of gid mappings */
299		uint32_t mnt_gidmap; /* [str] Array of gid mappings (as seen from callers namespace) */
300		uint64_t __spare2[43];
301		char str[]; /* Variable size part containing strings */
302		};
303
304		/* sb_flags (defined in kernel include/linux/fs.h) */
305		#ifndef SB_RDONLY
306		# define SB_RDONLY BIT(0) /* Mount read-only */
307		# define SB_NOSUID BIT(1) /* Ignore suid and sgid bits */
308		# define SB_NODEV BIT(2) /* Disallow access to device special files */
309		# define SB_NOEXEC BIT(3) /* Disallow program execution */
310		# define SB_SYNCHRONOUS BIT(4) /* Writes are synced at once */
311		# define SB_MANDLOCK BIT(6) /* Allow mandatory locks on an FS */
312		# define SB_DIRSYNC BIT(7) /* Directory modifications are synchronous */
313		# define SB_NOATIME BIT(10) /* Do not update access times. */
314		# define SB_NODIRATIME BIT(11) /* Do not update directory access times */
315		# define SB_SILENT BIT(15)
316		# define SB_POSIXACL BIT(16) /* Supports POSIX ACLs */
317		# define SB_INLINECRYPT BIT(17) /* Use blk-crypto for encrypted files */
318		# define SB_KERNMOUNT BIT(22) /* this is a kern_mount call */
319		# define SB_I_VERSION BIT(23) /* Update inode I_version field */
320		# define SB_LAZYTIME BIT(25) /* Update the on-disk [acm]times lazily */
321		#endif
322
323		/*
324		* @mask bits for statmount(2)
325		*/
326		#ifndef STATMOUNT_SB_BASIC
327		# define STATMOUNT_SB_BASIC 0x00000001U /* Want/got sb_... */
328		#endif
329		#ifndef STATMOUNT_MNT_BASIC
330		# define STATMOUNT_MNT_BASIC 0x00000002U /* Want/got mnt_... */
331		#endif
332		#ifndef STATMOUNT_PROPAGATE_FROM
333		# define STATMOUNT_PROPAGATE_FROM 0x00000004U /* Want/got propagate_from */
334		#endif
335		#ifndef STATMOUNT_MNT_ROOT
336		# define STATMOUNT_MNT_ROOT 0x00000008U /* Want/got mnt_root */
337		#endif
338		#ifndef STATMOUNT_MNT_POINT
339		# define STATMOUNT_MNT_POINT 0x00000010U /* Want/got mnt_point */
340		#endif
341		#ifndef STATMOUNT_FS_TYPE
342		# define STATMOUNT_FS_TYPE 0x00000020U /* Want/got fs_type */
343		#endif
344		#ifndef STATMOUNT_MNT_NS_ID
345		# define STATMOUNT_MNT_NS_ID 0x00000040U /* Want/got mnt_ns_id */
346		#endif
347		#ifndef STATMOUNT_MNT_OPTS
348		# define STATMOUNT_MNT_OPTS 0x00000080U /* Want/got mnt_opts */
349		#endif
350		#ifndef STATMOUNT_FS_SUBTYPE
351		# define STATMOUNT_FS_SUBTYPE 0x00000100U /* Want/got fs_subtype */
352		#endif
353		#ifndef STATMOUNT_SB_SOURCE
354		# define STATMOUNT_SB_SOURCE 0x00000200U /* Want/got sb_source */
355		#endif
356		#ifndef STATMOUNT_OPT_ARRAY
357		# define STATMOUNT_OPT_ARRAY 0x00000400U /* Want/got opt_... */
358		#endif
359		#ifndef STATMOUNT_OPT_SEC_ARRAY
360		# define STATMOUNT_OPT_SEC_ARRAY 0x00000800U /* Want/got opt_sec... */
361		#endif
362		#ifndef STATMOUNT_SUPPORTED_MASK
363		# define STATMOUNT_SUPPORTED_MASK 0x00001000U /* Want/got supported mask flags */
364		#endif
365		#ifndef STATMOUNT_MNT_UIDMAP
366		# define STATMOUNT_MNT_UIDMAP 0x00002000U /* Want/got uidmap... */
367		#endif
368		#ifndef STATMOUNT_MNT_GIDMAP
369		# define STATMOUNT_MNT_GIDMAP 0x00004000U /* Want/got gidmap... */
370		#endif
371		/*
372		* Special @mnt_id values that can be passed to listmount
373		*/
374		#ifndef LSMT_ROOT
375		# define LSMT_ROOT 0xffffffffffffffff /* root mount */
376		#endif
377
378		#ifndef LISTMOUNT_REVERSE
379		# define LISTMOUNT_REVERSE BIT(0) /* List later mounts first */
380		#endif
381
382		/* Don't use this "raw" version. See ul_statmount() below. */
383		#if defined(SYS_statmount)
384		static inline int ul_statmount_syscall(uint64_t mnt_id,
385		uint64_t ns_id,
386		uint64_t mask,
387		struct ul_statmount *buf,
388		size_t bufsize, unsigned int flags)
389		{
390		struct ul_mnt_id_req req = {
391		.size = MNT_ID_REQ_SIZE_VER1,
392		.mnt_id = mnt_id,
393		.param = mask,
394		.mnt_ns_id = ns_id
395		};
396
397		return syscall(SYS_statmount, &req, buf, bufsize, flags);
398		}
399
400		static inline int has_statmount(void)
401		{
402		errno = 0;
403
404		if (ul_statmount_syscall(0, 0, 0, NULL, 0, 0) < 0 && errno == ENOSYS)
405		return 0;
406		return 1;
407		}
408
409		/* This is a version of statmount() that reallocates @buf to be large enough to
410		* store data for the requested @id. This function never deallocates; it is the
411		* caller's responsibility.
412		*/
413		static inline int ul_statmount(uint64_t id,
414		uint64_t ns_id,
415		uint64_t mask,
416		struct ul_statmount **buf,
417		size_t *bufsiz,
418		unsigned int flags)
419		{
420		size_t sz;
421		int rc = 0;
422
423		if (!buf \|\| !bufsiz)
424		return -EINVAL;
425
426		sz = *bufsiz;
427		if (!sz)
428		sz = 32 * 1024;
429
430		do {
431		if (sz > *bufsiz) {
432		struct ul_statmount tmp = realloc(buf, sz);
433		if (!tmp)
434		return -ENOMEM;
435		*buf = tmp;
436		*bufsiz = sz;
437		}
438
439		errno = 0;
440		rc = ul_statmount_syscall(id, ns_id, mask, buf, bufsiz, flags);
441		if (!rc)
442		break;
443		if (errno != EOVERFLOW)
444		break;
445		if (sz >= SIZE_MAX / 2)
446		break;
447		sz <<= 1;
448		} while (rc);
449
450		return rc;
451		}
452		#endif /* SYS_statmount */
453
454
455		#if defined(SYS_listmount)
456		static inline ssize_t ul_listmount(uint64_t mnt_id,
457		uint64_t ns_id,
458		uint64_t last_mnt_id,
459		uint64_t list[], size_t num,
460		unsigned int flags)
461		{
462		struct ul_mnt_id_req req = {
463		.size = MNT_ID_REQ_SIZE_VER1,
464		.mnt_id = mnt_id,
465		.param = last_mnt_id,
466		.mnt_ns_id = ns_id
467		};
468
469		return syscall(SYS_listmount, &req, list, num, flags);
470		}
471
472		static inline int has_listmount(void)
473		{
474		uint64_t dummy;
475
476		errno = 0;
477
478		if (ul_listmount(LSMT_ROOT, 0, 0, &dummy, 1, LISTMOUNT_REVERSE) != 1)
479		return 0;
480		return 1;
481		}
482		#endif
483
484		#endif /* HAVE_STATMOUNT_API */
485		#endif /* HAVE_LINUX_MOUNT_H */
486
487		/*
488		* Default NTFS mount type (used by libmount and libblkid)
489		*/
490		#ifndef CONFIG_UL_NTFS_MOUNTTYPE
491		# define CONFIG_UL_NTFS_MOUNTTYPE "ntfs3"
492		#endif
493
494		/*
495		* Convert FS-type (as provided by libblkid or udev) to the preferred
496		* kernel FS driver (type used to mount the FS).
497		*
498		* This is a temporary solution; the final solution should be based on config
499		* files like /etc/mount/fs.d/<name> (from lib/configs.c) and managed by
500		* libmount.
501		*/
502		static inline const char ul_fstype_to_mounttype(const char fstype)
503	0	{
504	0	if (!fstype)
505	0	return NULL;
506	0
507	0	if (strcmp(fstype, "ntfs") == 0)
508	0	return CONFIG_UL_NTFS_MOUNTTYPE;
509	0
510	0	return NULL;
511	0	} Unexecuted instantiation: fuzz.c:ul_fstype_to_mounttype Unexecuted instantiation: tab.c:ul_fstype_to_mounttype Unexecuted instantiation: tab_listmount.c:ul_fstype_to_mounttype Unexecuted instantiation: tab_parse.c:ul_fstype_to_mounttype Unexecuted instantiation: utils.c:ul_fstype_to_mounttype Unexecuted instantiation: btrfs.c:ul_fstype_to_mounttype Unexecuted instantiation: cache.c:ul_fstype_to_mounttype Unexecuted instantiation: fs.c:ul_fstype_to_mounttype Unexecuted instantiation: fs_statmount.c:ul_fstype_to_mounttype Unexecuted instantiation: init.c:ul_fstype_to_mounttype Unexecuted instantiation: iter.c:ul_fstype_to_mounttype Unexecuted instantiation: optmap.c:ul_fstype_to_mounttype Unexecuted instantiation: optlist.c:ul_fstype_to_mounttype Unexecuted instantiation: optstr.c:ul_fstype_to_mounttype Unexecuted instantiation: version.c:ul_fstype_to_mounttype
512		#endif /* UTIL_LINUX_MOUNTUTILS_H */