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-rw-r--r--fs/notify/fanotify/fanotify.c38
-rw-r--r--fs/notify/fanotify/fanotify.h18
-rw-r--r--fs/notify/fanotify/fanotify_user.c89
3 files changed, 128 insertions, 17 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 95646f7c46ca..6d386080faf2 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -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);
}
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
index c12cbc270539..b44e70e44be6 100644
--- a/fs/notify/fanotify/fanotify.h
+++ b/fs/notify/fanotify/fanotify.h
@@ -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)
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index ba3e2d09eb44..f2d840ae4ded 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -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;
@@ -1776,7 +1816,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
unsigned int mark_cmd = flags & FANOTIFY_MARK_CMD_BITS;
unsigned int ignore = flags & FANOTIFY_MARK_IGNORE_BITS;
unsigned int obj_type, fid_mode;
- void *obj;
+ void *obj = NULL;
u32 umask = 0;
int ret;
@@ -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] =
generated by cgit (git 2.34.1) at 2025-05-02 16:59:54 +0000