From: Tuo Li islituo@gmail.com
[ Upstream commit a9e6ffbc5b7324b6639ee89028908b1e91ceed51 ]
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: TOTE Robot oslab@tsinghua.edu.cn Signed-off-by: Tuo Li islituo@gmail.com Signed-off-by: Jeff Layton jlayton@kernel.org Signed-off-by: Ilya Dryomov idryomov@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ceph/mdsmap.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/fs/ceph/mdsmap.c b/fs/ceph/mdsmap.c index abd9af7727ad..3c444b9cb17b 100644 --- a/fs/ceph/mdsmap.c +++ b/fs/ceph/mdsmap.c @@ -394,9 +394,11 @@ void ceph_mdsmap_destroy(struct ceph_mdsmap *m) { int i;
- for (i = 0; i < m->possible_max_rank; i++) - kfree(m->m_info[i].export_targets); - kfree(m->m_info); + 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); }