From f831c6c95d02d667b450b579bbfa781e96661120 Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Thu, 23 Jul 2020 15:32:25 +0800 Subject: [PATCH] ceph: fix use-after-free for fsc->mdsc [ Upstream commit a7caa88f8b72c136f9a401f498471b8a8e35370d ] If the ceph_mdsc_init() fails, it will free the mdsc already. Reported-by: syzbot+b57f46d8d6ea51960b8c@syzkaller.appspotmail.com Signed-off-by: Xiubo Li Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov Signed-off-by: Sasha Levin --- fs/ceph/mds_client.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index a2e903203bf9..0fa14d8b9c64 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -3682,7 +3682,6 @@ int ceph_mdsc_init(struct ceph_fs_client *fsc) return -ENOMEM; } - fsc->mdsc = mdsc; init_completion(&mdsc->safe_umount_waiters); init_waitqueue_head(&mdsc->session_close_wq); INIT_LIST_HEAD(&mdsc->waiting_for_map); @@ -3723,6 +3722,8 @@ int ceph_mdsc_init(struct ceph_fs_client *fsc) strscpy(mdsc->nodename, utsname()->nodename, sizeof(mdsc->nodename)); + + fsc->mdsc = mdsc; return 0; }