ext4: set lockdep subclass for the ea_inode in ext4_xattr_inode_cache_find()

BugLink: https://bugs.launchpad.net/bugs/2029808
commit b928dfdcb27d8fa59917b794cfba53052a2f050f upstream.

If the ea_inode has been pushed out of the inode cache while there is
still a reference in the mb_cache, the lockdep subclass will not be
set on the inode, which can lead to some lockdep false positives.

Fixes: 33d201e0277b ("ext4: fix lockdep warning about recursive inode locking")
Cc: stable@kernel.org
Reported-by: syzbot+d4b971e744b1f5439336@syzkaller.appspotmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20230524034951.779531-3-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index fd73b348b6eb74301558e8538238e3201ca12f60..2a249dd70478dd940a9ad64848e3164ebe4136e2 100644 (file)
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -1506,6 +1506,7 @@ ext4_xattr_inode_cache_find(struct inode *inode, const void *value,
                                     EXT4_IGET_EA_INODE);
                if (IS_ERR(ea_inode))
                        goto next_entry;
+               ext4_xattr_inode_set_class(ea_inode);
                if (i_size_read(ea_inode) == value_len &&
                    !ext4_xattr_inode_read(ea_inode, ea_data, value_len) &&
                    !ext4_xattr_inode_verify_hashes(ea_inode, NULL, ea_data,