From: "Steven Rostedt (Google)" rostedt@goodmis.org
stable inclusion from stable-v6.6.2 commit d8f492a059728bbd397defbc9b8d2f4159d869b5 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8IW7G
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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The top level events directory dentry does not have a d_fsdata set to a eventfs_file pointer. This dentry is still passed to eventfs_set_attr(). It can not assume that the d_fsdata is set. Check for that.
Link: https://lore.kernel.org/all/20231112104158.6638-1-milian.wolff@kdab.com/
Fixes: 9aaee3eebc91 ("eventfs: Save ownership and mode") Reported-by: Milian Wolff milian.wolff@kdab.com Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- fs/tracefs/event_inode.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 5fcfb634fec2..efbdc47c74dc 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -113,14 +113,14 @@ static int eventfs_set_attr(struct mnt_idmap *idmap, struct dentry *dentry,
mutex_lock(&eventfs_mutex); ef = dentry->d_fsdata; - if (ef->is_freed) { + if (ef && ef->is_freed) { /* Do not allow changes if the event is about to be removed. */ mutex_unlock(&eventfs_mutex); return -ENODEV; }
ret = simple_setattr(idmap, dentry, iattr); - if (!ret) + if (!ret && ef) update_attr(ef, iattr); mutex_unlock(&eventfs_mutex); return ret;