Merge tag 'ceph-for-6.1-rc6' of https://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:
 "Three filesystem bug fixes, intended for stable"

* tag 'ceph-for-6.1-rc6' of https://github.com/ceph/ceph-client:
  ceph: fix NULL pointer dereference for req->r_session
  ceph: avoid putting the realm twice when decoding snaps fails
  ceph: fix a NULL vs IS_ERR() check when calling ceph_lookup_inode()
  MAINTAINERS: git://github.com -> https://github.com for ceph

3 files changed, 15 insertions, 38 deletions

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index fb023f9fafcb..e54814d0c2f7 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -2248,7 +2248,6 @@ static int flush_mdlog_and_wait_inode_unsafe_requests(struct inode *inode)
 	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_mds_request *req1 = NULL, *req2 = NULL;
-	unsigned int max_sessions;
 	int ret, err = 0;
 
 	spin_lock(&ci->i_unsafe_lock);
@@ -2267,27 +2266,23 @@ static int flush_mdlog_and_wait_inode_unsafe_requests(struct inode *inode)
 	spin_unlock(&ci->i_unsafe_lock);
 
 	/*
-	 * The mdsc->max_sessions is unlikely to be changed
-	 * mostly, here we will retry it by reallocating the
-	 * sessions array memory to get rid of the mdsc->mutex
-	 * lock.
-	 */
-retry:
-	max_sessions = mdsc->max_sessions;
-
-	/*
 	 * Trigger to flush the journal logs in all the relevant MDSes
 	 * manually, or in the worst case we must wait at most 5 seconds
 	 * to wait the journal logs to be flushed by the MDSes periodically.
 	 */
-	if ((req1 || req2) && likely(max_sessions)) {
-		struct ceph_mds_session **sessions = NULL;
-		struct ceph_mds_session *s;
+	if (req1 || req2) {
 		struct ceph_mds_request *req;
+		struct ceph_mds_session **sessions;
+		struct ceph_mds_session *s;
+		unsigned int max_sessions;
 		int i;
 
+		mutex_lock(&mdsc->mutex);
+		max_sessions = mdsc->max_sessions;
+
 		sessions = kcalloc(max_sessions, sizeof(s), GFP_KERNEL);
 		if (!sessions) {
+			mutex_unlock(&mdsc->mutex);
 			err = -ENOMEM;
 			goto out;
 		}
@@ -2299,16 +2294,6 @@ retry:
 				s = req->r_session;
 				if (!s)
 					continue;
-				if (unlikely(s->s_mds >= max_sessions)) {
-					spin_unlock(&ci->i_unsafe_lock);
-					for (i = 0; i < max_sessions; i++) {
-						s = sessions[i];
-						if (s)
-							ceph_put_mds_session(s);
-					}
-					kfree(sessions);
-					goto retry;
-				}
 				if (!sessions[s->s_mds]) {
 					s = ceph_get_mds_session(s);
 					sessions[s->s_mds] = s;
@@ -2321,16 +2306,6 @@ retry:
 				s = req->r_session;
 				if (!s)
 					continue;
-				if (unlikely(s->s_mds >= max_sessions)) {
-					spin_unlock(&ci->i_unsafe_lock);
-					for (i = 0; i < max_sessions; i++) {
-						s = sessions[i];
-						if (s)
-							ceph_put_mds_session(s);
-					}
-					kfree(sessions);
-					goto retry;
-				}
 				if (!sessions[s->s_mds]) {
 					s = ceph_get_mds_session(s);
 					sessions[s->s_mds] = s;
@@ -2342,11 +2317,12 @@ retry:
 		/* the auth MDS */
 		spin_lock(&ci->i_ceph_lock);
 		if (ci->i_auth_cap) {
-		      s = ci->i_auth_cap->session;
-		      if (!sessions[s->s_mds])
-			      sessions[s->s_mds] = ceph_get_mds_session(s);
+			s = ci->i_auth_cap->session;
+			if (!sessions[s->s_mds])
+				sessions[s->s_mds] = ceph_get_mds_session(s);
 		}
 		spin_unlock(&ci->i_ceph_lock);
+		mutex_unlock(&mdsc->mutex);
 
 		/* send flush mdlog request to MDSes */
 		for (i = 0; i < max_sessions; i++) {
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 4af5e55abc15..bad9eeb6a1a5 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2492,7 +2492,7 @@ int ceph_getattr(struct user_namespace *mnt_userns, const struct path *path,
 			struct inode *parent;
 
 			parent = ceph_lookup_inode(sb, ceph_ino(inode));
-			if (!parent)
+			if (IS_ERR(parent))
 				return PTR_ERR(parent);
 
 			pci = ceph_inode(parent);
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index 864cdaa0d2bd..e4151852184e 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -763,7 +763,7 @@ int ceph_update_snap_trace(struct ceph_mds_client *mdsc,
 	struct ceph_mds_snap_realm *ri;    /* encoded */
 	__le64 *snaps;                     /* encoded */
 	__le64 *prior_parent_snaps;        /* encoded */
-	struct ceph_snap_realm *realm = NULL;
+	struct ceph_snap_realm *realm;
 	struct ceph_snap_realm *first_realm = NULL;
 	struct ceph_snap_realm *realm_to_rebuild = NULL;
 	int rebuild_snapcs;
@@ -774,6 +774,7 @@ int ceph_update_snap_trace(struct ceph_mds_client *mdsc,
 
 	dout("%s deletion=%d\n", __func__, deletion);
 more:
+	realm = NULL;
 	rebuild_snapcs = 0;
 	ceph_decode_need(&p, e, sizeof(*ri), bad);
 	ri = p;