Commit 5edbc204 authored by Steven Rostedt (Google)'s avatar Steven Rostedt (Google) Committed by Zheng Zengkai
Browse files

eventfs: Check for NULL ef in eventfs_set_attr() 

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=d8f492a059728bbd397defbc9b8d2f4159d869b5

--------------------------------

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: default avatarMilian Wolff <milian.wolff@kdab.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent d74eb76f

fs/tracefs/event_inode.c

+2 −2
Original line number Diff line number Diff line
@@ -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;