Commit a9e6ffbc authored by Tuo Li's avatar Tuo Li Committed by Ilya Dryomov
Browse files

ceph: fix possible null-pointer dereference in ceph_mdsmap_decode() 



kcalloc() is called to allocate memory for m->m_info, and if it fails,
ceph_mdsmap_destroy() behind the label out_err will be called:
  ceph_mdsmap_destroy(m);

In ceph_mdsmap_destroy(), m->m_info is dereferenced through:
  kfree(m->m_info[i].export_targets);

To fix this possible null-pointer dereference, check m->m_info before the
for loop to free m->m_info[i].export_targets.

[ jlayton: fix up whitespace damage
	   only kfree(m->m_info) if it's non-NULL ]

Reported-by: default avatarTOTE Robot <oslab@tsinghua.edu.cn>
Signed-off-by: default avatarTuo Li <islituo@gmail.com>
Signed-off-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent b2f9fa1f

fs/ceph/mdsmap.c

+5 −3
Original line number Diff line number Diff line
@@ -394,9 +394,11 @@ void ceph_mdsmap_destroy(struct ceph_mdsmap *m) 
{

	int i;



	if (m->m_info) {

		for (i = 0; i < m->possible_max_rank; i++)

			kfree(m->m_info[i].export_targets);

		kfree(m->m_info);

	}

	kfree(m->m_data_pg_pools);

	kfree(m);

}