@@ -181,3 +181,5 @@ static inline struct mnt_namespace *to_mnt_ns(struct ns_common *ns)
{
return container_of(ns, struct mnt_namespace, ns);
}
+
+struct mnt_namespace *mnt_ns_from_dentry(struct dentry *dentry);
@@ -2145,16 +2145,24 @@ struct mnt_namespace *get_sequential_mnt_ns(struct mnt_namespace *mntns, bool pr
}
}
+struct mnt_namespace *mnt_ns_from_dentry(struct dentry *dentry)
+{
+ if (!is_mnt_ns_file(dentry))
+ return NULL;
+
+ return to_mnt_ns(get_proc_ns(dentry->d_inode));
+}
+
static bool mnt_ns_loop(struct dentry *dentry)
{
/* Could bind mounting the mount namespace inode cause a
* mount namespace loop?
*/
- struct mnt_namespace *mnt_ns;
- if (!is_mnt_ns_file(dentry))
+ struct mnt_namespace *mnt_ns = mnt_ns_from_dentry(dentry);
+
+ if (!mnt_ns)
return false;
- mnt_ns = to_mnt_ns(get_proc_ns(dentry->d_inode));
return current->nsproxy->mnt_ns->seq >= mnt_ns->seq;
}
@@ -166,6 +166,8 @@ static bool fanotify_should_merge(struct fanotify_event *old,
case FANOTIFY_EVENT_TYPE_FS_ERROR:
return fanotify_error_event_equal(FANOTIFY_EE(old),
FANOTIFY_EE(new));
+ case FANOTIFY_EVENT_TYPE_MNT:
+ return false;
default:
WARN_ON_ONCE(1);
}
@@ -312,7 +314,10 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group,
pr_debug("%s: report_mask=%x mask=%x data=%p data_type=%d\n",
__func__, iter_info->report_mask, event_mask, data, data_type);
- if (!fid_mode) {
+ if (FAN_GROUP_FLAG(group, FAN_REPORT_MNT)) {
+ if (data_type != FSNOTIFY_EVENT_MNT)
+ return 0;
+ } else if (!fid_mode) {
/* Do we have path to open a file descriptor? */
if (!path)
return 0;
@@ -557,6 +562,20 @@ static struct fanotify_event *fanotify_alloc_path_event(const struct path *path,
return &pevent->fae;
}
+static struct fanotify_event *fanotify_alloc_mnt_event(u64 mnt_id, gfp_t gfp)
+{
+ struct fanotify_mnt_event *pevent;
+
+ pevent = kmem_cache_alloc(fanotify_mnt_event_cachep, gfp);
+ if (!pevent)
+ return NULL;
+
+ pevent->fae.type = FANOTIFY_EVENT_TYPE_MNT;
+ pevent->mnt_id = mnt_id;
+
+ return &pevent->fae;
+}
+
static struct fanotify_event *fanotify_alloc_perm_event(const void *data,
int data_type,
gfp_t gfp)
@@ -731,6 +750,7 @@ static struct fanotify_event *fanotify_alloc_event(
fid_mode);
struct inode *dirid = fanotify_dfid_inode(mask, data, data_type, dir);
const struct path *path = fsnotify_data_path(data, data_type);
+ u64 mnt_id = fsnotify_data_mnt_id(data, data_type);
struct mem_cgroup *old_memcg;
struct dentry *moved = NULL;
struct inode *child = NULL;
@@ -826,8 +846,12 @@ static struct fanotify_event *fanotify_alloc_event(
moved, &hash, gfp);
} else if (fid_mode) {
event = fanotify_alloc_fid_event(id, fsid, &hash, gfp);
- } else {
+ } else if (path) {
event = fanotify_alloc_path_event(path, &hash, gfp);
+ } else if (mnt_id) {
+ event = fanotify_alloc_mnt_event(mnt_id, gfp);
+ } else {
+ WARN_ON_ONCE(1);
}
if (!event)
@@ -927,7 +951,7 @@ static int fanotify_handle_event(struct fsnotify_group *group, u32 mask,
BUILD_BUG_ON(FAN_RENAME != FS_RENAME);
BUILD_BUG_ON(FAN_PRE_ACCESS != FS_PRE_ACCESS);
- BUILD_BUG_ON(HWEIGHT32(ALL_FANOTIFY_EVENT_BITS) != 22);
+ BUILD_BUG_ON(HWEIGHT32(ALL_FANOTIFY_EVENT_BITS) != 24);
mask = fanotify_group_event_mask(group, iter_info, &match_mask,
mask, data, data_type, dir);
@@ -1028,6 +1052,11 @@ static void fanotify_free_error_event(struct fsnotify_group *group,
mempool_free(fee, &group->fanotify_data.error_events_pool);
}
+static void fanotify_free_mnt_event(struct fanotify_event *event)
+{
+ kmem_cache_free(fanotify_mnt_event_cachep, FANOTIFY_ME(event));
+}
+
static void fanotify_free_event(struct fsnotify_group *group,
struct fsnotify_event *fsn_event)
{
@@ -1054,6 +1083,9 @@ static void fanotify_free_event(struct fsnotify_group *group,
case FANOTIFY_EVENT_TYPE_FS_ERROR:
fanotify_free_error_event(group, event);
break;
+ case FANOTIFY_EVENT_TYPE_MNT:
+ fanotify_free_mnt_event(event);
+ break;
default:
WARN_ON_ONCE(1);
}
@@ -9,6 +9,7 @@ extern struct kmem_cache *fanotify_mark_cache;
extern struct kmem_cache *fanotify_fid_event_cachep;
extern struct kmem_cache *fanotify_path_event_cachep;
extern struct kmem_cache *fanotify_perm_event_cachep;
+extern struct kmem_cache *fanotify_mnt_event_cachep;
/* Possible states of the permission event */
enum {
@@ -244,6 +245,7 @@ enum fanotify_event_type {
FANOTIFY_EVENT_TYPE_PATH_PERM,
FANOTIFY_EVENT_TYPE_OVERFLOW, /* struct fanotify_event */
FANOTIFY_EVENT_TYPE_FS_ERROR, /* struct fanotify_error_event */
+ FANOTIFY_EVENT_TYPE_MNT,
__FANOTIFY_EVENT_TYPE_NUM
};
@@ -409,12 +411,23 @@ struct fanotify_path_event {
struct path path;
};
+struct fanotify_mnt_event {
+ struct fanotify_event fae;
+ u64 mnt_id;
+};
+
static inline struct fanotify_path_event *
FANOTIFY_PE(struct fanotify_event *event)
{
return container_of(event, struct fanotify_path_event, fae);
}
+static inline struct fanotify_mnt_event *
+FANOTIFY_ME(struct fanotify_event *event)
+{
+ return container_of(event, struct fanotify_mnt_event, fae);
+}
+
/*
* Structure for permission fanotify events. It gets allocated and freed in
* fanotify_handle_event() since we wait there for user response. When the
@@ -466,6 +479,11 @@ static inline bool fanotify_is_error_event(u32 mask)
return mask & FAN_FS_ERROR;
}
+static inline bool fanotify_is_mnt_event(u32 mask)
+{
+ return mask & (FAN_MNT_ATTACH | FAN_MNT_DETACH);
+}
+
static inline const struct path *fanotify_event_path(struct fanotify_event *event)
{
if (event->type == FANOTIFY_EVENT_TYPE_PATH)
@@ -113,6 +113,7 @@ struct kmem_cache *fanotify_mark_cache __ro_after_init;
struct kmem_cache *fanotify_fid_event_cachep __ro_after_init;
struct kmem_cache *fanotify_path_event_cachep __ro_after_init;
struct kmem_cache *fanotify_perm_event_cachep __ro_after_init;
+struct kmem_cache *fanotify_mnt_event_cachep __ro_after_init;
#define FANOTIFY_EVENT_ALIGN 4
#define FANOTIFY_FID_INFO_HDR_LEN \
@@ -123,6 +124,8 @@ struct kmem_cache *fanotify_perm_event_cachep __ro_after_init;
(sizeof(struct fanotify_event_info_error))
#define FANOTIFY_RANGE_INFO_LEN \
(sizeof(struct fanotify_event_info_range))
+#define FANOTIFY_MNT_INFO_LEN \
+ (sizeof(struct fanotify_event_info_mnt))
static int fanotify_fid_info_len(int fh_len, int name_len)
{
@@ -178,6 +181,8 @@ static size_t fanotify_event_len(unsigned int info_mode,
fh_len = fanotify_event_object_fh_len(event);
event_len += fanotify_fid_info_len(fh_len, dot_len);
}
+ if (fanotify_is_mnt_event(event->mask))
+ event_len += FANOTIFY_MNT_INFO_LEN;
if (info_mode & FAN_REPORT_PIDFD)
event_len += FANOTIFY_PIDFD_INFO_LEN;
@@ -405,6 +410,25 @@ static int process_access_response(struct fsnotify_group *group,
return -ENOENT;
}
+static size_t copy_mnt_info_to_user(struct fanotify_event *event,
+ char __user *buf, int count)
+{
+ struct fanotify_event_info_mnt info = { };
+
+ info.hdr.info_type = FAN_EVENT_INFO_TYPE_MNT;
+ info.hdr.len = FANOTIFY_MNT_INFO_LEN;
+
+ if (WARN_ON(count < info.hdr.len))
+ return -EFAULT;
+
+ info.mnt_id = FANOTIFY_ME(event)->mnt_id;
+
+ if (copy_to_user(buf, &info, sizeof(info)))
+ return -EFAULT;
+
+ return info.hdr.len;
+}
+
static size_t copy_error_info_to_user(struct fanotify_event *event,
char __user *buf, int count)
{
@@ -700,6 +724,15 @@ static int copy_info_records_to_user(struct fanotify_event *event,
total_bytes += ret;
}
+ if (fanotify_is_mnt_event(event->mask)) {
+ ret = copy_mnt_info_to_user(event, buf, count);
+ if (ret < 0)
+ return ret;
+ buf += ret;
+ count -= ret;
+ total_bytes += ret;
+ }
+
return total_bytes;
}
@@ -1508,6 +1541,14 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
if ((flags & FAN_REPORT_PIDFD) && (flags & FAN_REPORT_TID))
return -EINVAL;
+ /* Don't allow mixing mnt events with inode events for now */
+ if (flags & FAN_REPORT_MNT) {
+ if (class != FAN_CLASS_NOTIF)
+ return -EINVAL;
+ if (flags & (FANOTIFY_FID_BITS | FAN_REPORT_FD_ERROR))
+ return -EINVAL;
+ }
+
if (event_f_flags & ~FANOTIFY_INIT_ALL_EVENT_F_BITS)
return -EINVAL;
@@ -1767,7 +1808,6 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
int dfd, const char __user *pathname)
{
struct inode *inode = NULL;
- struct vfsmount *mnt = NULL;
struct fsnotify_group *group;
struct path path;
struct fan_fsid __fsid, *fsid = NULL;
@@ -1800,6 +1840,9 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
case FAN_MARK_FILESYSTEM:
obj_type = FSNOTIFY_OBJ_TYPE_SB;
break;
+ case FAN_MARK_MNTNS:
+ obj_type = FSNOTIFY_OBJ_TYPE_MNTNS;
+ break;
default:
return -EINVAL;
}
@@ -1847,6 +1890,19 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
return -EINVAL;
group = fd_file(f)->private_data;
+ /* Only report mount events on mnt namespace */
+ if (FAN_GROUP_FLAG(group, FAN_REPORT_MNT)) {
+ if (mask & ~FANOTIFY_MOUNT_EVENTS)
+ return -EINVAL;
+ if (mark_type != FAN_MARK_MNTNS)
+ return -EINVAL;
+ } else {
+ if (mask & FANOTIFY_MOUNT_EVENTS)
+ return -EINVAL;
+ if (mark_type == FAN_MARK_MNTNS)
+ return -EINVAL;
+ }
+
/*
* An unprivileged user is not allowed to setup mount nor filesystem
* marks. This also includes setting up such marks by a group that
@@ -1888,7 +1944,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
* point.
*/
fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS);
- if (mask & ~(FANOTIFY_FD_EVENTS|FANOTIFY_EVENT_FLAGS) &&
+ if (mask & ~(FANOTIFY_FD_EVENTS|FANOTIFY_MOUNT_EVENTS|FANOTIFY_EVENT_FLAGS) &&
(!fid_mode || mark_type == FAN_MARK_MOUNT))
return -EINVAL;
@@ -1938,17 +1994,21 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
}
/* inode held in place by reference to path; group by fget on fd */
- if (mark_type == FAN_MARK_INODE) {
+ if (obj_type == FSNOTIFY_OBJ_TYPE_INODE) {
inode = path.dentry->d_inode;
obj = inode;
- } else {
- mnt = path.mnt;
- if (mark_type == FAN_MARK_MOUNT)
- obj = mnt;
- else
- obj = mnt->mnt_sb;
+ } else if (obj_type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) {
+ obj = path.mnt;
+ } else if (obj_type == FSNOTIFY_OBJ_TYPE_SB) {
+ obj = path.mnt->mnt_sb;
+ } else if (obj_type == FSNOTIFY_OBJ_TYPE_MNTNS) {
+ obj = mnt_ns_from_dentry(path.dentry);
}
+ ret = -EINVAL;
+ if (!obj)
+ goto path_put_and_out;
+
/*
* If some other task has this inode open for write we should not add
* an ignore mask, unless that ignore mask is supposed to survive
@@ -1956,10 +2016,10 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
*/
if (mark_cmd == FAN_MARK_ADD && (flags & FANOTIFY_MARK_IGNORE_BITS) &&
!(flags & FAN_MARK_IGNORED_SURV_MODIFY)) {
- ret = mnt ? -EINVAL : -EISDIR;
+ ret = !inode ? -EINVAL : -EISDIR;
/* FAN_MARK_IGNORE requires SURV_MODIFY for sb/mount/dir marks */
if (ignore == FAN_MARK_IGNORE &&
- (mnt || S_ISDIR(inode->i_mode)))
+ (!inode || S_ISDIR(inode->i_mode)))
goto path_put_and_out;
ret = 0;
@@ -1968,7 +2028,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
}
/* Mask out FAN_EVENT_ON_CHILD flag for sb/mount/non-dir marks */
- if (mnt || !S_ISDIR(inode->i_mode)) {
+ if (!inode || !S_ISDIR(inode->i_mode)) {
mask &= ~FAN_EVENT_ON_CHILD;
umask = FAN_EVENT_ON_CHILD;
/*
@@ -2042,7 +2102,7 @@ static int __init fanotify_user_setup(void)
FANOTIFY_DEFAULT_MAX_USER_MARKS);
BUILD_BUG_ON(FANOTIFY_INIT_FLAGS & FANOTIFY_INTERNAL_GROUP_FLAGS);
- BUILD_BUG_ON(HWEIGHT32(FANOTIFY_INIT_FLAGS) != 13);
+ BUILD_BUG_ON(HWEIGHT32(FANOTIFY_INIT_FLAGS) != 14);
BUILD_BUG_ON(HWEIGHT32(FANOTIFY_MARK_FLAGS) != 11);
fanotify_mark_cache = KMEM_CACHE(fanotify_mark,
@@ -2055,6 +2115,7 @@ static int __init fanotify_user_setup(void)
fanotify_perm_event_cachep =
KMEM_CACHE(fanotify_perm_event, SLAB_PANIC);
}
+ fanotify_mnt_event_cachep = KMEM_CACHE(fanotify_mnt_event, SLAB_PANIC);
fanotify_max_queued_events = FANOTIFY_DEFAULT_MAX_EVENTS;
init_user_ns.ucount_max[UCOUNT_FANOTIFY_GROUPS] =
@@ -121,6 +121,11 @@ static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
seq_printf(m, "fanotify sdev:%x mflags:%x mask:%x ignored_mask:%x\n",
sb->s_dev, mflags, mark->mask, mark->ignore_mask);
+ } else if (mark->connector->type == FSNOTIFY_OBJ_TYPE_MNTNS) {
+ struct mnt_namespace *mnt_ns = fsnotify_conn_mntns(mark->connector);
+
+ seq_printf(m, "fanotify mnt_ns:%u mflags:%x mask:%x ignored_mask:%x\n",
+ mnt_ns->ns.inum, mflags, mark->mask, mark->ignore_mask);
}
}
@@ -25,7 +25,7 @@
#define FANOTIFY_FID_BITS (FAN_REPORT_DFID_NAME_TARGET)
-#define FANOTIFY_INFO_MODES (FANOTIFY_FID_BITS | FAN_REPORT_PIDFD)
+#define FANOTIFY_INFO_MODES (FANOTIFY_FID_BITS | FAN_REPORT_PIDFD | FAN_REPORT_MNT)
/*
* fanotify_init() flags that require CAP_SYS_ADMIN.
@@ -38,7 +38,8 @@
FAN_REPORT_PIDFD | \
FAN_REPORT_FD_ERROR | \
FAN_UNLIMITED_QUEUE | \
- FAN_UNLIMITED_MARKS)
+ FAN_UNLIMITED_MARKS | \
+ FAN_REPORT_MNT)
/*
* fanotify_init() flags that are allowed for user without CAP_SYS_ADMIN.
@@ -58,7 +59,7 @@
#define FANOTIFY_INTERNAL_GROUP_FLAGS (FANOTIFY_UNPRIV)
#define FANOTIFY_MARK_TYPE_BITS (FAN_MARK_INODE | FAN_MARK_MOUNT | \
- FAN_MARK_FILESYSTEM)
+ FAN_MARK_FILESYSTEM | FAN_MARK_MNTNS)
#define FANOTIFY_MARK_CMD_BITS (FAN_MARK_ADD | FAN_MARK_REMOVE | \
FAN_MARK_FLUSH)
@@ -109,10 +110,13 @@
/* Events that can only be reported with data type FSNOTIFY_EVENT_ERROR */
#define FANOTIFY_ERROR_EVENTS (FAN_FS_ERROR)
+#define FANOTIFY_MOUNT_EVENTS (FAN_MNT_ATTACH | FAN_MNT_DETACH)
+
/* Events that user can request to be notified on */
#define FANOTIFY_EVENTS (FANOTIFY_PATH_EVENTS | \
FANOTIFY_INODE_EVENTS | \
- FANOTIFY_ERROR_EVENTS)
+ FANOTIFY_ERROR_EVENTS | \
+ FANOTIFY_MOUNT_EVENTS)
/* Extra flags that may be reported with event or control handling of events */
#define FANOTIFY_EVENT_FLAGS (FAN_EVENT_ON_CHILD | FAN_ONDIR)
@@ -28,6 +28,8 @@
/* #define FAN_DIR_MODIFY 0x00080000 */ /* Deprecated (reserved) */
#define FAN_PRE_ACCESS 0x00100000 /* Pre-content access hook */
+#define FAN_MNT_ATTACH 0x01000000 /* Mount was attached */
+#define FAN_MNT_DETACH 0x02000000 /* Mount was detached */
#define FAN_EVENT_ON_CHILD 0x08000000 /* Interested in child events */
@@ -64,6 +66,7 @@
#define FAN_REPORT_NAME 0x00000800 /* Report events with name */
#define FAN_REPORT_TARGET_FID 0x00001000 /* Report dirent target id */
#define FAN_REPORT_FD_ERROR 0x00002000 /* event->fd can report error */
+#define FAN_REPORT_MNT 0x00004000 /* Report mount events */
/* Convenience macro - FAN_REPORT_NAME requires FAN_REPORT_DIR_FID */
#define FAN_REPORT_DFID_NAME (FAN_REPORT_DIR_FID | FAN_REPORT_NAME)
@@ -94,6 +97,7 @@
#define FAN_MARK_INODE 0x00000000
#define FAN_MARK_MOUNT 0x00000010
#define FAN_MARK_FILESYSTEM 0x00000100
+#define FAN_MARK_MNTNS 0x00000110
/*
* Convenience macro - FAN_MARK_IGNORE requires FAN_MARK_IGNORED_SURV_MODIFY
@@ -147,6 +151,7 @@ struct fanotify_event_metadata {
#define FAN_EVENT_INFO_TYPE_PIDFD 4
#define FAN_EVENT_INFO_TYPE_ERROR 5
#define FAN_EVENT_INFO_TYPE_RANGE 6
+#define FAN_EVENT_INFO_TYPE_MNT 7
/* Special info types for FAN_RENAME */
#define FAN_EVENT_INFO_TYPE_OLD_DFID_NAME 10
@@ -200,6 +205,11 @@ struct fanotify_event_info_range {
__u64 count;
};
+struct fanotify_event_info_mnt {
+ struct fanotify_event_info_header hdr;
+ __u64 mnt_id;
+};
+
/*
* User space may need to record additional information about its decision.
* The extra information type records what kind of information is included.
@@ -3395,6 +3395,10 @@ static int selinux_path_notify(const struct path *path, u64 mask,
case FSNOTIFY_OBJ_TYPE_INODE:
perm = FILE__WATCH;
break;
+ case FSNOTIFY_OBJ_TYPE_MNTNS:
+ /* Maybe introduce FILE__WATCH_MOUNTNS? */
+ perm = FILE__WATCH_MOUNT;
+ break;
default:
return -EINVAL;
}
Add notifications for attaching and detaching mounts. The following new event masks are added: FAN_MNT_ATTACH - Mount was attached FAN_MNT_DETACH - Mount was detached If a mount is moved, then the event is reported with (FAN_MNT_ATTACH | FAN_MNT_DETACH). These events add an info record of type FAN_EVENT_INFO_TYPE_MNT containing these fields identifying the affected mounts: __u64 mnt_id - the ID of the mount (see statmount(2)) FAN_REPORT_MNT must be supplied to fanotify_init() to receive these events and no other type of event can be received with this report type. Marks are added with FAN_MARK_MNTNS, which records the mount namespace from an nsfs file (e.g. /proc/self/ns/mnt). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> --- fs/mount.h | 2 + fs/namespace.c | 14 +++-- fs/notify/fanotify/fanotify.c | 38 +++++++++++-- fs/notify/fanotify/fanotify.h | 18 +++++++ fs/notify/fanotify/fanotify_user.c | 87 +++++++++++++++++++++++++----- fs/notify/fdinfo.c | 5 ++ include/linux/fanotify.h | 12 +++-- include/uapi/linux/fanotify.h | 10 ++++ security/selinux/hooks.c | 4 ++ 9 files changed, 167 insertions(+), 23 deletions(-)