diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 9dac7f6e72d2..aff1ab3c32aa 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -838,9 +838,8 @@ out: } /* - * Get cached fsid of the filesystem containing the object from any connector. - * All connectors are supposed to have the same fsid, but we do not verify that - * here. + * Get cached fsid of the filesystem containing the object from any mark. + * All marks are supposed to have the same fsid, but we do not verify that here. */ static __kernel_fsid_t fanotify_get_fsid(struct fsnotify_iter_info *iter_info) { @@ -849,17 +848,9 @@ static __kernel_fsid_t fanotify_get_fsid(struct fsnotify_iter_info *iter_info) __kernel_fsid_t fsid = {}; fsnotify_foreach_iter_mark_type(iter_info, mark, type) { - struct fsnotify_mark_connector *conn; - - conn = READ_ONCE(mark->connector); - /* Mark is just getting destroyed or created? */ - if (!conn) + if (!(mark->flags & FSNOTIFY_MARK_FLAG_HAS_FSID)) continue; - if (!(conn->flags & FSNOTIFY_CONN_FLAG_HAS_FSID)) - continue; - /* Pairs with smp_wmb() in fsnotify_add_mark_list() */ - smp_rmb(); - fsid = conn->fsid; + fsid = FANOTIFY_MARK(mark)->fsid; if (WARN_ON_ONCE(!fsid.val[0] && !fsid.val[1])) continue; return fsid; @@ -1068,7 +1059,7 @@ static void fanotify_freeing_mark(struct fsnotify_mark *mark, static void fanotify_free_mark(struct fsnotify_mark *fsn_mark) { - kmem_cache_free(fanotify_mark_cache, fsn_mark); + kmem_cache_free(fanotify_mark_cache, FANOTIFY_MARK(fsn_mark)); } const struct fsnotify_ops fanotify_fsnotify_ops = { diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 6936671e148d..f3b9ef60f0c0 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -489,6 +489,16 @@ static inline unsigned int fanotify_event_hash_bucket( return event->hash & FANOTIFY_HTABLE_MASK; } +struct fanotify_mark { + struct fsnotify_mark fsn_mark; + __kernel_fsid_t fsid; +}; + +static inline struct fanotify_mark *FANOTIFY_MARK(struct fsnotify_mark *mark) +{ + return container_of(mark, struct fanotify_mark, fsn_mark); +} + static inline unsigned int fanotify_mark_user_flags(struct fsnotify_mark *mark) { unsigned int mflags = 0; diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 4d765c72496f..e3d836d4d156 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -1199,6 +1199,7 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, __kernel_fsid_t *fsid) { struct ucounts *ucounts = group->fanotify_data.ucounts; + struct fanotify_mark *fan_mark; struct fsnotify_mark *mark; int ret; @@ -1211,17 +1212,26 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, !inc_ucount(ucounts->ns, ucounts->uid, UCOUNT_FANOTIFY_MARKS)) return ERR_PTR(-ENOSPC); - mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL); - if (!mark) { + fan_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL); + if (!fan_mark) { ret = -ENOMEM; goto out_dec_ucounts; } + mark = &fan_mark->fsn_mark; fsnotify_init_mark(mark, group); if (fan_flags & FAN_MARK_EVICTABLE) mark->flags |= FSNOTIFY_MARK_FLAG_NO_IREF; - ret = fsnotify_add_mark_locked(mark, connp, obj_type, 0, fsid); + /* Cache fsid of filesystem containing the marked object */ + if (fsid) { + fan_mark->fsid = *fsid; + mark->flags |= FSNOTIFY_MARK_FLAG_HAS_FSID; + } else { + fan_mark->fsid.val[0] = fan_mark->fsid.val[1] = 0; + } + + ret = fsnotify_add_mark_locked(mark, connp, obj_type, 0); if (ret) { fsnotify_put_mark(mark); goto out_dec_ucounts; @@ -1935,7 +1945,7 @@ static int __init fanotify_user_setup(void) BUILD_BUG_ON(HWEIGHT32(FANOTIFY_INIT_FLAGS) != 12); BUILD_BUG_ON(HWEIGHT32(FANOTIFY_MARK_FLAGS) != 11); - fanotify_mark_cache = KMEM_CACHE(fsnotify_mark, + fanotify_mark_cache = KMEM_CACHE(fanotify_mark, SLAB_PANIC|SLAB_ACCOUNT); fanotify_fid_event_cachep = KMEM_CACHE(fanotify_fid_event, SLAB_PANIC); diff --git a/fs/notify/mark.c b/fs/notify/mark.c index c74ef947447d..d6944ff86ffa 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -537,8 +537,7 @@ int fsnotify_compare_groups(struct fsnotify_group *a, struct fsnotify_group *b) } static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp, - unsigned int obj_type, - __kernel_fsid_t *fsid) + unsigned int obj_type) { struct fsnotify_mark_connector *conn; @@ -550,14 +549,7 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp, conn->flags = 0; conn->type = obj_type; conn->obj = connp; - /* Cache fsid of filesystem containing the object */ - if (fsid) { - conn->fsid = *fsid; - conn->flags = FSNOTIFY_CONN_FLAG_HAS_FSID; - } else { - conn->fsid.val[0] = conn->fsid.val[1] = 0; - conn->flags = 0; - } + conn->flags = 0; fsnotify_get_sb_connectors(conn); /* @@ -608,8 +600,7 @@ out: */ static int fsnotify_add_mark_list(struct fsnotify_mark *mark, fsnotify_connp_t *connp, - unsigned int obj_type, - int add_flags, __kernel_fsid_t *fsid) + unsigned int obj_type, int add_flags) { struct fsnotify_mark *lmark, *last = NULL; struct fsnotify_mark_connector *conn; @@ -619,41 +610,15 @@ static int fsnotify_add_mark_list(struct fsnotify_mark *mark, if (WARN_ON(!fsnotify_valid_obj_type(obj_type))) return -EINVAL; - /* Backend is expected to check for zero fsid (e.g. tmpfs) */ - if (fsid && WARN_ON_ONCE(!fsid->val[0] && !fsid->val[1])) - return -ENODEV; - restart: spin_lock(&mark->lock); conn = fsnotify_grab_connector(connp); if (!conn) { spin_unlock(&mark->lock); - err = fsnotify_attach_connector_to_object(connp, obj_type, - fsid); + err = fsnotify_attach_connector_to_object(connp, obj_type); if (err) return err; goto restart; - } else if (fsid && !(conn->flags & FSNOTIFY_CONN_FLAG_HAS_FSID)) { - conn->fsid = *fsid; - /* Pairs with smp_rmb() in fanotify_get_fsid() */ - smp_wmb(); - conn->flags |= FSNOTIFY_CONN_FLAG_HAS_FSID; - } else if (fsid && (conn->flags & FSNOTIFY_CONN_FLAG_HAS_FSID) && - (fsid->val[0] != conn->fsid.val[0] || - fsid->val[1] != conn->fsid.val[1])) { - /* - * Backend is expected to check for non uniform fsid - * (e.g. btrfs), but maybe we missed something? - * Only allow setting conn->fsid once to non zero fsid. - * inotify and non-fid fanotify groups do not set nor test - * conn->fsid. - */ - pr_warn_ratelimited("%s: fsid mismatch on object of type %u: " - "%x.%x != %x.%x\n", __func__, conn->type, - fsid->val[0], fsid->val[1], - conn->fsid.val[0], conn->fsid.val[1]); - err = -EXDEV; - goto out_err; } /* is mark the first mark? */ @@ -703,7 +668,7 @@ out_err: */ int fsnotify_add_mark_locked(struct fsnotify_mark *mark, fsnotify_connp_t *connp, unsigned int obj_type, - int add_flags, __kernel_fsid_t *fsid) + int add_flags) { struct fsnotify_group *group = mark->group; int ret = 0; @@ -723,7 +688,7 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark, fsnotify_get_mark(mark); /* for g_list */ spin_unlock(&mark->lock); - ret = fsnotify_add_mark_list(mark, connp, obj_type, add_flags, fsid); + ret = fsnotify_add_mark_list(mark, connp, obj_type, add_flags); if (ret) goto err; @@ -742,14 +707,13 @@ err: } int fsnotify_add_mark(struct fsnotify_mark *mark, fsnotify_connp_t *connp, - unsigned int obj_type, int add_flags, - __kernel_fsid_t *fsid) + unsigned int obj_type, int add_flags) { int ret; struct fsnotify_group *group = mark->group; fsnotify_group_lock(group); - ret = fsnotify_add_mark_locked(mark, connp, obj_type, add_flags, fsid); + ret = fsnotify_add_mark_locked(mark, connp, obj_type, add_flags); fsnotify_group_unlock(group); return ret; } diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index c0892d75ce33..a80b525ca653 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -472,10 +472,8 @@ typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t; struct fsnotify_mark_connector { spinlock_t lock; unsigned short type; /* Type of object [lock] */ -#define FSNOTIFY_CONN_FLAG_HAS_FSID 0x01 #define FSNOTIFY_CONN_FLAG_HAS_IREF 0x02 unsigned short flags; /* flags [lock] */ - __kernel_fsid_t fsid; /* fsid of filesystem containing object */ union { /* Object pointer [lock] */ fsnotify_connp_t *obj; @@ -530,6 +528,7 @@ struct fsnotify_mark { #define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x0100 #define FSNOTIFY_MARK_FLAG_NO_IREF 0x0200 #define FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS 0x0400 +#define FSNOTIFY_MARK_FLAG_HAS_FSID 0x0800 unsigned int flags; /* flags [mark->lock] */ }; @@ -763,11 +762,10 @@ extern struct fsnotify_mark *fsnotify_find_mark(fsnotify_connp_t *connp, /* attach the mark to the object */ extern int fsnotify_add_mark(struct fsnotify_mark *mark, fsnotify_connp_t *connp, unsigned int obj_type, - int add_flags, __kernel_fsid_t *fsid); + int add_flags); extern int fsnotify_add_mark_locked(struct fsnotify_mark *mark, fsnotify_connp_t *connp, - unsigned int obj_type, int add_flags, - __kernel_fsid_t *fsid); + unsigned int obj_type, int add_flags); /* attach the mark to the inode */ static inline int fsnotify_add_inode_mark(struct fsnotify_mark *mark, @@ -775,15 +773,14 @@ static inline int fsnotify_add_inode_mark(struct fsnotify_mark *mark, int add_flags) { return fsnotify_add_mark(mark, &inode->i_fsnotify_marks, - FSNOTIFY_OBJ_TYPE_INODE, add_flags, NULL); + FSNOTIFY_OBJ_TYPE_INODE, add_flags); } static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark, struct inode *inode, int add_flags) { return fsnotify_add_mark_locked(mark, &inode->i_fsnotify_marks, - FSNOTIFY_OBJ_TYPE_INODE, add_flags, - NULL); + FSNOTIFY_OBJ_TYPE_INODE, add_flags); } /* given a group and a mark, flag mark to be freed when all references are dropped */