Merge tag 'ceph-for-5.16-rc6' of git://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:
 "An SGID directory handling fix (marked for stable), a metrics
  accounting fix and two fixups to appease static checkers"

* tag 'ceph-for-5.16-rc6' of git://github.com/ceph/ceph-client:
  ceph: fix up non-directory creation in SGID directories
  ceph: initialize pathlen variable in reconnect_caps_cb
  ceph: initialize i_size variable in ceph_sync_read
  ceph: fix duplicate increment of opened_inodes metric

fs/ceph/caps.c

@@ -4350,7 +4350,7 @@ void ceph_get_fmode(struct ceph_inode_info *ci, int fmode, int count)
 {
 	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(ci->vfs_inode.i_sb);
 	int bits = (fmode << 1) | 1;
-	bool is_opened = false;
+	bool already_opened = false;
 	int i;
 
 	if (count == 1)
@@ -4358,19 +4358,19 @@ void ceph_get_fmode(struct ceph_inode_info *ci, int fmode, int count)
 
 	spin_lock(&ci->i_ceph_lock);
 	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
-		if (bits & (1 << i))
-			ci->i_nr_by_mode[i] += count;
-
 		/*
-		 * If any of the mode ref is larger than 1,
+		 * If any of the mode ref is larger than 0,
 		 * that means it has been already opened by
 		 * others. Just skip checking the PIN ref.
 		 */
-		if (i && ci->i_nr_by_mode[i] > 1)
-			is_opened = true;
+		if (i && ci->i_nr_by_mode[i])
+			already_opened = true;
+
+		if (bits & (1 << i))
+			ci->i_nr_by_mode[i] += count;
 	}
 
-	if (!is_opened)
+	if (!already_opened)
 		percpu_counter_inc(&mdsc->metric.opened_inodes);
 	spin_unlock(&ci->i_ceph_lock);
 }

fs/ceph/file.c

@@ -605,13 +605,25 @@ static int ceph_finish_async_create(struct inode *dir, struct dentry *dentry,
 	in.cap.realm = cpu_to_le64(ci->i_snap_realm->ino);
 	in.cap.flags = CEPH_CAP_FLAG_AUTH;
 	in.ctime = in.mtime = in.atime = iinfo.btime;
-	in.mode = cpu_to_le32((u32)mode);
 	in.truncate_seq = cpu_to_le32(1);
 	in.truncate_size = cpu_to_le64(-1ULL);
 	in.xattr_version = cpu_to_le64(1);
 	in.uid = cpu_to_le32(from_kuid(&init_user_ns, current_fsuid()));
-	in.gid = cpu_to_le32(from_kgid(&init_user_ns, dir->i_mode & S_ISGID ?
-				dir->i_gid : current_fsgid()));
+	if (dir->i_mode & S_ISGID) {
+		in.gid = cpu_to_le32(from_kgid(&init_user_ns, dir->i_gid));
+
+		/* Directories always inherit the setgid bit. */
+		if (S_ISDIR(mode))
+			mode |= S_ISGID;
+		else if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP) &&
+			 !in_group_p(dir->i_gid) &&
+			 !capable_wrt_inode_uidgid(&init_user_ns, dir, CAP_FSETID))
+			mode &= ~S_ISGID;
+	} else {
+		in.gid = cpu_to_le32(from_kgid(&init_user_ns, current_fsgid()));
+	}
+	in.mode = cpu_to_le32((u32)mode);
+
 	in.nlink = cpu_to_le32(1);
 	in.max_size = cpu_to_le64(lo->stripe_unit);
 
@@ -847,7 +859,7 @@ static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to,
 	ssize_t ret;
 	u64 off = iocb->ki_pos;
 	u64 len = iov_iter_count(to);
-	u64 i_size;
+	u64 i_size = i_size_read(inode);
 
 	dout("sync_read on file %p %llu~%u %s\n", file, off, (unsigned)len,
 	     (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");

fs/ceph/mds_client.c

@@ -3683,7 +3683,7 @@ static int reconnect_caps_cb(struct inode *inode, struct ceph_cap *cap,
 	struct ceph_pagelist *pagelist = recon_state->pagelist;
 	struct dentry *dentry;
 	char *path;
-	int pathlen, err;
+	int pathlen = 0, err;
 	u64 pathbase;
 	u64 snap_follows;
 
@@ -3703,7 +3703,6 @@ static int reconnect_caps_cb(struct inode *inode, struct ceph_cap *cap,
 		}
 	} else {
 		path = NULL;
-		pathlen = 0;
 		pathbase = 0;
 	}