[PATCH v9 26/31] fanotify: Report fid info for file related file system errors
From: Gabriel Krisman Bertazi <hidden>
Date: 2021-10-25 19:33:33
Also in:
linux-api, linux-fsdevel
Subsystem:
fanotify, filesystems (vfs and infrastructure), fsnotify: filesystem notification infrastructure, the rest · Maintainers:
Jan Kara, Alexander Viro, Christian Brauner, Linus Torvalds
Plumb the pieces to add a FID report to error records. Since all error event memory must be pre-allocated, we pre-allocate the maximum file handle size possible, such that it should always fit. For errors that don't expose a file handle report it with an invalid FID. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Gabriel Krisman Bertazi <redacted> --- Changes since v8: - Drop comment (Amir) - Move report dereference till after null check (jan) - Move has_object_fh hunk to earlier patch (jan) Changes since v7: - Move WARN_ON to separate patch (Amir) - Avoid duplication in the structure definition (Amir) Changes since v6: - pass fsid from handle_events Changes since v5: - Use preallocated MAX_HANDLE_SZ FH buffer - Report superblock errors with a zerolength INVALID FID (jan, amir) --- fs/notify/fanotify/fanotify.c | 11 +++++++++++ fs/notify/fanotify/fanotify.h | 6 ++++++ 2 files changed, 17 insertions(+)
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 45df610debbe..465f07e70e6d 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c@@ -609,7 +609,9 @@ static struct fanotify_event *fanotify_alloc_error_event( { struct fs_error_report *report = fsnotify_data_error_report(data, data_type); + struct inode *inode; struct fanotify_error_event *fee; + int fh_len; if (WARN_ON_ONCE(!report)) return NULL;
@@ -622,6 +624,15 @@ static struct fanotify_event *fanotify_alloc_error_event( fee->err_count = 1; fee->fsid = *fsid; + inode = report->inode; + fh_len = fanotify_encode_fh_len(inode); + + /* Bad fh_len. Fallback to using an invalid fh. Should never happen. */ + if (!fh_len && inode) + inode = NULL; + + fanotify_encode_fh(&fee->object_fh, inode, fh_len, NULL, 0); + *hash ^= fanotify_hash_fsid(fsid); return &fee->fae;
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
index f51ab6e556e8..edd7587adcc5 100644
--- a/fs/notify/fanotify/fanotify.h
+++ b/fs/notify/fanotify/fanotify.h@@ -208,6 +208,8 @@ struct fanotify_error_event { u32 err_count; /* Suppressed errors count */ __kernel_fsid_t fsid; /* FSID this error refers to. */ + + FANOTIFY_INLINE_FH(object_fh, MAX_HANDLE_SZ); }; static inline struct fanotify_error_event *
@@ -222,6 +224,8 @@ static inline __kernel_fsid_t *fanotify_event_fsid(struct fanotify_event *event) return &FANOTIFY_FE(event)->fsid; else if (event->type == FANOTIFY_EVENT_TYPE_FID_NAME) return &FANOTIFY_NE(event)->fsid; + else if (event->type == FANOTIFY_EVENT_TYPE_FS_ERROR) + return &FANOTIFY_EE(event)->fsid; else return NULL; }
@@ -233,6 +237,8 @@ static inline struct fanotify_fh *fanotify_event_object_fh( return &FANOTIFY_FE(event)->object_fh; else if (event->type == FANOTIFY_EVENT_TYPE_FID_NAME) return fanotify_info_file_fh(&FANOTIFY_NE(event)->info); + else if (event->type == FANOTIFY_EVENT_TYPE_FS_ERROR) + return &FANOTIFY_EE(event)->object_fh; else return NULL; }
--
2.33.0