5.15-stable review patch. If anyone has any objections, please let me know.
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From: Amir Goldstein amir73il@gmail.com
[ Upstream commit dabe729dddca550446e9cc118c96d1f91703345b ]
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 Signed-off-by: Chuck Lever chuck.lever@oracle.com --- include/linux/fsnotify.h | 22 ++++++++++++++++------ kernel/audit_fsnotify.c | 3 +-- 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 70e6b147a76ad..a327a95fa68f1 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 */ @@ -266,12 +272,16 @@ 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 c428312938e95..7a506b65e8630 100644 --- a/kernel/audit_fsnotify.c +++ b/kernel/audit_fsnotify.c @@ -161,8 +161,7 @@ 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 edbeffee64b8e..fd7b30a2d9a4b 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)