From 1f15b2dc0a737198fc5e21c3a15678e9749d3354 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Tue, 6 Feb 2024 06:32:02 -0500 Subject: [PATCH] eventfs: Have eventfs_iterate() stop immediately if ei->is_freed is set commit e109deadb73318cf4a3bd61287d969f705df278f upstream. 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 Cc: Mark Rutland Cc: Mathieu Desnoyers Cc: Andrew Morton Cc: Linus Torvalds Cc: Al Viro Cc: Christian Brauner Cc: Greg Kroah-Hartman Signed-off-by: Steven Rostedt (Google) Signed-off-by: Greg Kroah-Hartman --- fs/tracefs/event_inode.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index e6c40a3e07c25..63eabca959a5a 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -750,11 +750,12 @@ 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; -- 2.47.3