diff mbox series

[v6.7,v2,04/23] eventfs: Have eventfs_iterate() stop immediately if ei->is_freed is set

Message ID 20240206113358.729003384@rostedt.homelinux.com
State New
Headers
Series eventfs: Linus's updates for 6.7 |

Commit Message

Steven Rostedt Feb. 6, 2024, 11:32 a.m. UTC 
  From: "Steven Rostedt (Google)" <rostedt@goodmis.org>

If ei->is_freed is set in eventfs_iterate(), it means that the directory
that is being iterated on is in the process of being freed. Just exit the
loop immediately when that is ever detected, and separate out the return
of the entry->callback() from ei->is_freed.

Link: https://lore.kernel.org/linux-trace-kernel/20240104220048.016261289@goodmis.org

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
(cherry picked from commit e109deadb73318cf4a3bd61287d969f705df278f)
---
 fs/tracefs/event_inode.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c
index 72912b5f9a90..0aca6910efb3 100644
--- a/fs/tracefs/event_inode.c
+++ b/fs/tracefs/event_inode.c
@@ -788,11 +788,12 @@  static int eventfs_iterate(struct file *file, struct dir_context *ctx)
 		name = entry->name;
 
 		mutex_lock(&eventfs_mutex);
-		/* If ei->is_freed, then the event itself may be too */
-		if (!ei->is_freed)
-			r = entry->callback(name, &mode, &cdata, &fops);
-		else
-			r = -1;
+		/* If ei->is_freed then just bail here, nothing more to do */
+		if (ei->is_freed) {
+			mutex_unlock(&eventfs_mutex);
+			goto out;
+		}
+		r = entry->callback(name, &mode, &cdata, &fops);
 		mutex_unlock(&eventfs_mutex);
 		if (r <= 0)
 			continue;