Description

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: Fix memory leak if ntfs_read_mft failed Label ATTR_ROOT in ntfs_read_mft() sets is_root = true and ni->ni_flags |= NI_FLAG_DIR, then next attr will goto label ATTR_ALLOC and alloc ni->dir.alloc_run. However two states are not always consistent and can make memory leak. 1) attr_name in ATTR_ROOT does not fit the condition it will set is_root = true but NI_FLAG_DIR is not set. 2) next attr_name in ATTR_ALLOC fits the condition and alloc ni->dir.alloc_run 3) in cleanup function ni_clear(), when NI_FLAG_DIR is set, it frees ni->dir.alloc_run, otherwise it frees ni->file.run 4) because NI_FLAG_DIR is not set in this case, ni->dir.alloc_run is leaked as kmemleak reported: unreferenced object 0xffff888003bc5480 (size 64): backtrace: [] __kmalloc_node+0x4e/0x1c0 [] kvmalloc_node+0x39/0x1f0 [] run_add_entry+0x18a/0xa40 [ntfs3] [] run_unpack+0x75d/0x8e0 [ntfs3] [] run_unpack_ex+0xbc/0x500 [ntfs3] [] ntfs_iget5+0xb25/0x2dd0 [ntfs3] [] ntfs_fill_super+0x218d/0x3580 [ntfs3] [] get_tree_bdev+0x3fb/0x710 [] vfs_get_tree+0x8e/0x280 [] path_mount+0xf3c/0x1930 [] do_mount+0xf3/0x110 ... Fix this by always setting is_root and NI_FLAG_DIR together.