Описание
In the Linux kernel, the following vulnerability has been resolved:
ceph: fix possible deadlock when holding Fwb to get inline_data
1, mount with wsync. 2, create a file with O_RDWR, and the request was sent to mds.0:
ceph_atomic_open()--> ceph_mdsc_do_request(openc) finish_open(file, dentry, ceph_open)--> ceph_open()--> ceph_init_file()--> ceph_init_file_info()--> ceph_uninline_data()--> { ... if (inline_version == 1 || /* initial version, no data */ inline_version == CEPH_INLINE_NONE) goto out_unlock; ... }
The inline_version will be 1, which is the initial version for the new create file. And here the ci->i_inline_version will keep with 1, it's buggy.
3, buffer write to the file immediately:
ceph_write_iter()--> ceph_get_caps(file, need=Fw, want=Fb, ...); generic_perform_write()--> a_ops->writ...
In the Linux kernel, the following vulnerability has been resolved:
ceph: fix possible deadlock when holding Fwb to get inline_data
1, mount with wsync. 2, create a file with O_RDWR, and the request was sent to mds.0:
ceph_atomic_open()--> ceph_mdsc_do_request(openc) finish_open(file, dentry, ceph_open)--> ceph_open()--> ceph_init_file()--> ceph_init_file_info()--> ceph_uninline_data()--> { ... if (inline_version == 1 || /* initial version, no data */ inline_version == CEPH_INLINE_NONE) goto out_unlock; ... }
The inline_version will be 1, which is the initial version for the new create file. And here the ci->i_inline_version will keep with 1, it's buggy.
3, buffer write to the file immediately:
ceph_write_iter()--> ceph_get_caps(file, need=Fw, want=Fb, ...); generic_perform_write()--> a_ops->write_begin()--> ceph_write_begin()--> netfs_write_begin()--> netfs_begin_read()--> netfs_rreq_submit_slice()--> netfs_read_from_server()--> rreq->netfs_ops->issue_read()--> ceph_netfs_issue_read()--> { ... if (ci->i_inline_version != CEPH_INLINE_NONE && ceph_netfs_issue_op_inline(subreq)) return; ... } ceph_put_cap_refs(ci, Fwb);
The ceph_netfs_issue_op_inline() will send a getattr(Fsr) request to mds.1.
4, then the mds.1 will request the rd lock for CInode::filelock from the auth mds.0, the mds.0 will do the CInode::filelock state transation from excl --> sync, but it need to revoke the Fxwb caps back from the clients.
While the kernel client has aleady held the Fwb caps and waiting for the getattr(Fsr).
It's deadlock!
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: ceph: fix possible deadlock when holding Fwb to get inline_data 1, mount with wsync. 2, create a file with O_RDWR, and the request was sent to mds.0: ceph_atomic_open()--> ceph_mdsc_do_request(openc) finish_open(file, dentry, ceph_open)--> ceph_open()--> ceph_init_file()--> ceph_init_file_info()--> ceph_uninline_data()--> { ... if (inline_version == 1 || /* initial version, no data */ inline_version == CEPH_INLINE_NONE) goto out_unlock; ... } The inline_version will be 1, which is the initial version for the new create file. And here the ci->i_inline_version will keep with 1, it's buggy. 3, buffer write to the file immediately: ceph_write_iter()--> ceph_get_caps(file, need=Fw, want=Fb, ...); generic_perform_write()--> a_ops->write_begin()--> ceph_write_begin()--> netfs_write_begin()--> netfs_begin_read()--> netfs_rreq_submit_slice()--> netfs_read_from_server()--> rreq->netfs_ops->issue_read()--> ceph_netfs_issue_rea...
In the Linux kernel, the following vulnerability has been resolved: ceph: fix possible deadlock when holding Fwb to get inline_data 1, mount with wsync. 2, create a file with O_RDWR, and the request was sent to mds.0: ceph_atomic_open()--> ceph_mdsc_do_request(openc) finish_open(file, dentry, ceph_open)--> ceph_open()--> ceph_init_file()--> ceph_init_file_info()--> ceph_uninline_data()--> { ... if (inline_version == 1 || /* initial version, no data */ inline_version == CEPH_INLINE_NONE) goto out_unlock; ... } The inline_version will be 1, which is the initial version for the new create file. And here the ci->i_inline_version will keep with 1, it's buggy. 3, buffer write to the file immediately: ceph_write_iter()--> ceph_get_caps(file, need=Fw, want=Fb, ...); generic_perform_write()--> a_ops->write_begin()--> ceph_write_begin()--> netfs_write_begin()--> netfs_begin_read()--> netfs_rreq_submit_slice()--> netfs_read_from_server()--> rreq->netfs_ops->issue_read()--> ceph_netfs_issue_rea...
In the Linux kernel, the following vulnerability has been resolved: ceph: fix possible deadlock when holding Fwb to get inline_data 1, mount with wsync. 2, create a file with O_RDWR, and the request was sent to mds.0: ceph_atomic_open()--> ceph_mdsc_do_request(openc) finish_open(file, dentry, ceph_open)--> ceph_open()--> ceph_init_file()--> ceph_init_file_info()--> ceph_uninline_data()--> { ... if (inline_version == 1 || /* initial version, no data */ inline_version == CEPH_INLINE_NONE) goto out_unlock; ... } The inline_version will be 1, which is the initial version for the new create file. And here the ci->i_inline_version will keep with 1, it's buggy. 3, buffer write to the file immediately: ceph_write_iter()--> ceph_get_caps(file, need=Fw, want=Fb, ...); generic_perform_write()--> a_ops->write_b
In the Linux kernel, the following vulnerability has been resolved: c ...