From: Jan Kara jack@suse.cz
commit 9385a84d7e1f658bb2d96ab798393e4b16268aaa upstream.
Pass fsnotify_iter_info into ->handle_event() handler so that it can release and reacquire SRCU lock via fsnotify_prepare_user_wait() and fsnotify_finish_user_wait() functions. These functions also make sure current marks are appropriately pinned so that iteration protected by srcu in fsnotify() stays safe.
Reviewed-by: Miklos Szeredi mszeredi@redhat.com Reviewed-by: Amir Goldstein amir73il@gmail.com Signed-off-by: Jan Kara jack@suse.cz [mruffell: backport: removing const keyword and minor realignment] Signed-off-by: Matthew Ruffell matthew.ruffell@canonical.com --- fs/notify/dnotify/dnotify.c | 3 ++- fs/notify/fanotify/fanotify.c | 3 ++- fs/notify/fsnotify.c | 19 +++++++++++++------ fs/notify/inotify/inotify.h | 3 ++- fs/notify/inotify/inotify_fsnotify.c | 3 ++- fs/notify/inotify/inotify_user.c | 2 +- include/linux/fsnotify_backend.h | 3 ++- kernel/audit_fsnotify.c | 3 ++- kernel/audit_tree.c | 3 ++- kernel/audit_watch.c | 3 ++- 10 files changed, 30 insertions(+), 15 deletions(-)
diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c index 6faaf710e563..264bfd99a694 100644 --- a/fs/notify/dnotify/dnotify.c +++ b/fs/notify/dnotify/dnotify.c @@ -86,7 +86,8 @@ static int dnotify_handle_event(struct fsnotify_group *group, struct fsnotify_mark *inode_mark, struct fsnotify_mark *vfsmount_mark, u32 mask, void *data, int data_type, - const unsigned char *file_name, u32 cookie) + const unsigned char *file_name, u32 cookie, + struct fsnotify_iter_info *iter_info) { struct dnotify_mark *dn_mark; struct dnotify_struct *dn; diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 8a459b179183..4944956cdbd9 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -174,7 +174,8 @@ static int fanotify_handle_event(struct fsnotify_group *group, struct fsnotify_mark *inode_mark, struct fsnotify_mark *fanotify_mark, u32 mask, void *data, int data_type, - const unsigned char *file_name, u32 cookie) + const unsigned char *file_name, u32 cookie, + struct fsnotify_iter_info *iter_info) { int ret = 0; struct fanotify_event_info *event; diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index a64adc2fced9..19c75b446314 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -131,7 +131,8 @@ static int send_to_group(struct inode *to_tell, struct fsnotify_mark *vfsmount_mark, __u32 mask, void *data, int data_is, u32 cookie, - const unsigned char *file_name) + const unsigned char *file_name, + struct fsnotify_iter_info *iter_info) { struct fsnotify_group *group = NULL; __u32 inode_test_mask = 0; @@ -182,7 +183,7 @@ static int send_to_group(struct inode *to_tell,
return group->ops->handle_event(group, to_tell, inode_mark, vfsmount_mark, mask, data, data_is, - file_name, cookie); + file_name, cookie, iter_info); }
/* @@ -197,8 +198,9 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, struct hlist_node *inode_node = NULL, *vfsmount_node = NULL; struct fsnotify_mark *inode_mark = NULL, *vfsmount_mark = NULL; struct fsnotify_group *inode_group, *vfsmount_group; + struct fsnotify_iter_info iter_info; struct mount *mnt; - int idx, ret = 0; + int ret = 0; /* global tests shouldn't care about events on child only the specific event */ __u32 test_mask = (mask & ~FS_EVENT_ON_CHILD);
@@ -227,7 +229,7 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, !(mnt && test_mask & mnt->mnt_fsnotify_mask)) return 0;
- idx = srcu_read_lock(&fsnotify_mark_srcu); + iter_info.srcu_idx = srcu_read_lock(&fsnotify_mark_srcu);
if ((mask & FS_MODIFY) || (test_mask & to_tell->i_fsnotify_mask)) @@ -276,8 +278,13 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, vfsmount_mark = NULL; } } + + iter_info.inode_mark = inode_mark; + iter_info.vfsmount_mark = vfsmount_mark; + ret = send_to_group(to_tell, inode_mark, vfsmount_mark, mask, - data, data_is, cookie, file_name); + data, data_is, cookie, file_name, + &iter_info);
if (ret && (mask & ALL_FSNOTIFY_PERM_EVENTS)) goto out; @@ -291,7 +298,7 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, } ret = 0; out: - srcu_read_unlock(&fsnotify_mark_srcu, idx); + srcu_read_unlock(&fsnotify_mark_srcu, iter_info.srcu_idx);
return ret; } diff --git a/fs/notify/inotify/inotify.h b/fs/notify/inotify/inotify.h index ed855ef6f077..726b06b303b8 100644 --- a/fs/notify/inotify/inotify.h +++ b/fs/notify/inotify/inotify.h @@ -27,6 +27,7 @@ extern int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_mark *inode_mark, struct fsnotify_mark *vfsmount_mark, u32 mask, void *data, int data_type, - const unsigned char *file_name, u32 cookie); + const unsigned char *file_name, u32 cookie, + struct fsnotify_iter_info *iter_info);
extern const struct fsnotify_ops inotify_fsnotify_ops; diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c index 2cd900c2c737..79a5f06b9100 100644 --- a/fs/notify/inotify/inotify_fsnotify.c +++ b/fs/notify/inotify/inotify_fsnotify.c @@ -67,7 +67,8 @@ int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_mark *inode_mark, struct fsnotify_mark *vfsmount_mark, u32 mask, void *data, int data_type, - const unsigned char *file_name, u32 cookie) + const unsigned char *file_name, u32 cookie, + struct fsnotify_iter_info *iter_info) { struct inotify_inode_mark *i_mark; struct inotify_event_info *event; diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index b8d08d0d0a4d..6cea8b2131a3 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -494,7 +494,7 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark,
/* Queue ignore event for the watch */ inotify_handle_event(group, NULL, fsn_mark, NULL, FS_IN_IGNORED, - NULL, FSNOTIFY_EVENT_NONE, NULL, 0); + NULL, FSNOTIFY_EVENT_NONE, NULL, 0, NULL);
i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark); /* remove this mark from the idr */ diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index c7c5ea590d54..ddc13584cbe2 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -98,7 +98,8 @@ struct fsnotify_ops { struct fsnotify_mark *inode_mark, struct fsnotify_mark *vfsmount_mark, u32 mask, void *data, int data_type, - const unsigned char *file_name, u32 cookie); + const unsigned char *file_name, u32 cookie, + struct fsnotify_iter_info *iter_info); void (*free_group_priv)(struct fsnotify_group *group); void (*freeing_mark)(struct fsnotify_mark *mark, struct fsnotify_group *group); void (*free_event)(struct fsnotify_event *event); diff --git a/kernel/audit_fsnotify.c b/kernel/audit_fsnotify.c index 27c6046c2c3d..94aa9995f41a 100644 --- a/kernel/audit_fsnotify.c +++ b/kernel/audit_fsnotify.c @@ -169,7 +169,8 @@ static int audit_mark_handle_event(struct fsnotify_group *group, struct fsnotify_mark *inode_mark, struct fsnotify_mark *vfsmount_mark, u32 mask, void *data, int data_type, - const unsigned char *dname, u32 cookie) + const unsigned char *dname, u32 cookie, + struct fsnotify_iter_info *iter_info) { struct audit_fsnotify_mark *audit_mark; struct inode *inode = NULL; diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 5efe9b299a12..9443b7fd6d90 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -951,7 +951,8 @@ static int audit_tree_handle_event(struct fsnotify_group *group, struct fsnotify_mark *inode_mark, struct fsnotify_mark *vfsmount_mark, u32 mask, void *data, int data_type, - const unsigned char *file_name, u32 cookie) + const unsigned char *file_name, u32 cookie, + struct fsnotify_iter_info *iter_info) { return 0; } diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index f45a9a5d3e47..40fb562ca404 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -485,7 +485,8 @@ static int audit_watch_handle_event(struct fsnotify_group *group, struct fsnotify_mark *inode_mark, struct fsnotify_mark *vfsmount_mark, u32 mask, void *data, int data_type, - const unsigned char *dname, u32 cookie) + const unsigned char *dname, u32 cookie, + struct fsnotify_iter_info *iter_info) { struct inode *inode; struct audit_parent *parent;