diff options
| author | Amir Goldstein <amir73il@gmail.com> | 2021-10-25 16:27:18 -0300 |
|---|---|---|
| committer | Jan Kara <jack@suse.cz> | 2021-10-27 12:32:34 +0200 |
| commit | dabe729dddca550446e9cc118c96d1f91703345b (patch) | |
| tree | 9a0768c3fc088a1e2d5a5bca458d16651d52fb10 | |
| parent | fd5a3ff49a19aa69e2bc1e26e98037c2d778e61a (diff) | |
fsnotify: clarify contract for create event hooks
Clarify argument names and contract for fsnotify_create() and
fsnotify_mkdir() to reflect the anomaly of kernfs, which leaves dentries
negavite after mkdir/create.
Remove the WARN_ON(!inode) in audit code that were added by the Fixes
commit under the wrong assumption that dentries cannot be negative after
mkdir/create.
Fixes: aa93bdc5500c ("fsnotify: use helpers to access data by data_type")
Link: https://lore.kernel.org/linux-fsdevel/87mtp5yz0q.fsf@collabora.com/
Link: https://lore.kernel.org/r/20211025192746.66445-4-krisman@collabora.com
Reviewed-by: Jan Kara <jack@suse.cz>
Reported-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
| -rw-r--r-- | include/linux/fsnotify.h | 22 | ||||
| -rw-r--r-- | kernel/audit_fsnotify.c | 3 | ||||
| -rw-r--r-- | kernel/audit_watch.c | 3 |
3 files changed, 18 insertions, 10 deletions
diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h index df0fa4687a18..1e5f7435a4b5 100644 --- a/include/linux/fsnotify.h +++ b/include/linux/fsnotify.h @@ -192,16 +192,22 @@ static inline void fsnotify_inoderemove(struct inode *inode) /* * fsnotify_create - 'name' was linked in + * + * Caller must make sure that dentry->d_name is stable. + * Note: some filesystems (e.g. kernfs) leave @dentry negative and instantiate + * ->d_inode later */ -static inline void fsnotify_create(struct inode *inode, struct dentry *dentry) +static inline void fsnotify_create(struct inode *dir, struct dentry *dentry) { - audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE); + audit_inode_child(dir, dentry, AUDIT_TYPE_CHILD_CREATE); - fsnotify_dirent(inode, dentry, FS_CREATE); + fsnotify_dirent(dir, dentry, FS_CREATE); } /* * fsnotify_link - new hardlink in 'inode' directory + * + * Caller must make sure that new_dentry->d_name is stable. * Note: We have to pass also the linked inode ptr as some filesystems leave * new_dentry->d_inode NULL and instantiate inode pointer later */ @@ -230,12 +236,16 @@ static inline void fsnotify_unlink(struct inode *dir, struct dentry *dentry) /* * fsnotify_mkdir - directory 'name' was created + * + * Caller must make sure that dentry->d_name is stable. + * Note: some filesystems (e.g. kernfs) leave @dentry negative and instantiate + * ->d_inode later */ -static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry) +static inline void fsnotify_mkdir(struct inode *dir, struct dentry *dentry) { - audit_inode_child(inode, dentry, AUDIT_TYPE_CHILD_CREATE); + audit_inode_child(dir, dentry, AUDIT_TYPE_CHILD_CREATE); - fsnotify_dirent(inode, dentry, FS_CREATE | FS_ISDIR); + fsnotify_dirent(dir, dentry, FS_CREATE | FS_ISDIR); } /* diff --git a/kernel/audit_fsnotify.c b/kernel/audit_fsnotify.c index 60739d5e3373..02348b48447c 100644 --- a/kernel/audit_fsnotify.c +++ b/kernel/audit_fsnotify.c @@ -160,8 +160,7 @@ static int audit_mark_handle_event(struct fsnotify_mark *inode_mark, u32 mask, audit_mark = container_of(inode_mark, struct audit_fsnotify_mark, mark); - if (WARN_ON_ONCE(inode_mark->group != audit_fsnotify_group) || - WARN_ON_ONCE(!inode)) + if (WARN_ON_ONCE(inode_mark->group != audit_fsnotify_group)) return 0; if (mask & (FS_CREATE|FS_MOVED_TO|FS_DELETE|FS_MOVED_FROM)) { diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index 2acf7ca49154..223eed7b39cd 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -472,8 +472,7 @@ static int audit_watch_handle_event(struct fsnotify_mark *inode_mark, u32 mask, parent = container_of(inode_mark, struct audit_parent, mark); - if (WARN_ON_ONCE(inode_mark->group != audit_watch_group) || - WARN_ON_ONCE(!inode)) + if (WARN_ON_ONCE(inode_mark->group != audit_watch_group)) return 0; if (mask & (FS_CREATE|FS_MOVED_TO) && inode) |