syzbot call pidfd_ioctl() with cmd "PIDFD_GET_TIME_NAMESPACE" and disabled CONFIG_TIME_NS, since time_ns is NULL, it will make NULL ponter deref in open_namespace. Reported-and-tested-by: syzbot+34a0ee986f61f15da35d@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=34a0ee986f61f15da35d Signed-off-by: Edward Adam Davis <eadavis@xxxxxx> --- fs/pidfs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/pidfs.c b/fs/pidfs.c index c9cb14181def..fe0ddab48f57 100644 --- a/fs/pidfs.c +++ b/fs/pidfs.c @@ -168,6 +168,8 @@ static long pidfd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) case PIDFD_GET_TIME_NAMESPACE: get_time_ns(nsp->time_ns); ns_common = to_ns_common(nsp->time_ns); + if (!nsp->time_ns) + return -EINVAL; break; case PIDFD_GET_TIME_FOR_CHILDREN_NAMESPACE: get_time_ns(nsp->time_ns_for_children); -- 2.43.0
