Skip to contentSkip to conversation

tracefs: Some minor fixes

PATCH Superseded Steven Rostedt 1 participant 3 messages May 22, 2024

Subsystems (2)
Stable branch Tracing

v1 of 2 Superseded Latest is v2 →

lore
Share & tools
lore

Steven Rostedt

author maintainer
#0 lore raw

cover tracefs: Some minor fixes

Steven Rostedt (Google) (2):
eventfs: Keep the directories from having the same inode number as files
tracefs: Update inode permissions on remount

----

 fs/tracefs/event_inode.c | 23 ++++++++++++++++++-----
 fs/tracefs/inode.c       | 15 ++++++++++++---
 2 files changed, 30 insertions(+), 8 deletions(-)
author maintainer
#1 lore raw

PATCH 1/2 eventfs: Keep the directories from having the same inode number as files

From: "Steven Rostedt (Google)" <[email protected]>

The directories require unique inode numbers but all the eventfs files have the same inode number. Prevent the directories from having the same inode numbers as the files as that can confuse some tooling.

Cc [email protected]
Fixes 834bf76add3e6 ("eventfs: Save directory inodes in the eventfs_inode structure")
Signed-off-by Steven Rostedt (Google) <[email protected]>
---
 fs/tracefs/event_inode.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
fs/tracefs/event_inode.c +5 -1
index 0256afdd4acf..55a40a730b10 100644
@@ -50,8 +50,12 @@ static struct eventfs_root_inode *get_root_inode(struct eventfs_inode *ei)
 /* Just try to make something consistent and unique */
 static int eventfs_dir_ino(struct eventfs_inode *ei)
 {
-	if (!ei->ino)
+	if (!ei->ino) {
 		ei->ino = get_next_ino();
+		/* Must not have the file inode number */
+		if (ei->ino == EVENTFS_FILE_INODE_INO)
+			ei->ino = get_next_ino();
+	}
 
 	return ei->ino;
 }
Signature · 1 line
2.43.0
author maintainer
#2 lore raw

PATCH 2/2 tracefs: Update inode permissions on remount

In reply to Steven Rostedt

From: "Steven Rostedt (Google)" <[email protected]>

When a remount happens, if a gid or uid is specified update the inodes to have the same gid and uid. This will allow the simplification of the permissions logic for the dynamically created files and directories.

Cc [email protected]
Fixes baa23a8d4360d ("tracefs: Reset permissions on remount if permissions are options")
Signed-off-by Steven Rostedt (Google) <[email protected]>
---
 fs/tracefs/event_inode.c | 17 +++++++++++++----
 fs/tracefs/inode.c       | 15 ++++++++++++---
 2 files changed, 25 insertions(+), 7 deletions(-)
fs/tracefs/event_inode.c +13 -4
index 55a40a730b10..5dfb1ccd56ea 100644
@@ -317,20 +317,29 @@ void eventfs_remount(struct tracefs_inode *ti, bool update_uid, bool update_gid)
 	if (!ei)
 		return;
 
-	if (update_uid)
+	if (update_uid) {
 		ei->attr.mode &= ~EVENTFS_SAVE_UID;
+		ei->attr.uid = ti->vfs_inode.i_uid;
+	}
+
 
-	if (update_gid)
+	if (update_gid) {
 		ei->attr.mode &= ~EVENTFS_SAVE_GID;
+		ei->attr.gid = ti->vfs_inode.i_gid;
+	}
 
 	if (!ei->entry_attrs)
 		return;
 
 	for (int i = 0; i < ei->nr_entries; i++) {
-		if (update_uid)
+		if (update_uid) {
 			ei->entry_attrs[i].mode &= ~EVENTFS_SAVE_UID;
-		if (update_gid)
+			ei->entry_attrs[i].uid = ti->vfs_inode.i_uid;
+		}
+		if (update_gid) {
 			ei->entry_attrs[i].mode &= ~EVENTFS_SAVE_GID;
+			ei->entry_attrs[i].gid = ti->vfs_inode.i_gid;
+		}
 	}
 }
fs/tracefs/inode.c +12 -3
index a827f6a716c4..9252e0d78ea2 100644
@@ -373,12 +373,21 @@ static int tracefs_apply_options(struct super_block *sb, bool remount)
 
 		rcu_read_lock();
 		list_for_each_entry_rcu(ti, &tracefs_inodes, list) {
-			if (update_uid)
+			if (update_uid) {
 				ti->flags &= ~TRACEFS_UID_PERM_SET;
+				ti->vfs_inode.i_uid = fsi->uid;
+			}
 
-			if (update_gid)
+			if (update_gid) {
 				ti->flags &= ~TRACEFS_GID_PERM_SET;
-
+				ti->vfs_inode.i_gid = fsi->gid;
+			}
+
+			/*
+			 * Note, the above ti->vfs_inode updates are
+			 * used in eventfs_remount() so they must come
+			 * before calling it.
+			 */
 			if (ti->flags & TRACEFS_EVENT_INODE)
 				eventfs_remount(ti, update_uid, update_gid);
 		}
Signature · 1 line
2.43.0