CVE-2024-53155

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ocfs2: fix uninitialized value in ocfs2_file_read_iter()<br /> <br /> Syzbot has reported the following KMSAN splat:<br /> <br /> BUG: KMSAN: uninit-value in ocfs2_file_read_iter+0x9a4/0xf80<br /> ocfs2_file_read_iter+0x9a4/0xf80<br /> __io_read+0x8d4/0x20f0<br /> io_read+0x3e/0xf0<br /> io_issue_sqe+0x42b/0x22c0<br /> io_wq_submit_work+0xaf9/0xdc0<br /> io_worker_handle_work+0xd13/0x2110<br /> io_wq_worker+0x447/0x1410<br /> ret_from_fork+0x6f/0x90<br /> ret_from_fork_asm+0x1a/0x30<br /> <br /> Uninit was created at:<br /> __alloc_pages_noprof+0x9a7/0xe00<br /> alloc_pages_mpol_noprof+0x299/0x990<br /> alloc_pages_noprof+0x1bf/0x1e0<br /> allocate_slab+0x33a/0x1250<br /> ___slab_alloc+0x12ef/0x35e0<br /> kmem_cache_alloc_bulk_noprof+0x486/0x1330<br /> __io_alloc_req_refill+0x84/0x560<br /> io_submit_sqes+0x172f/0x2f30<br /> __se_sys_io_uring_enter+0x406/0x41c0<br /> __x64_sys_io_uring_enter+0x11f/0x1a0<br /> x64_sys_call+0x2b54/0x3ba0<br /> do_syscall_64+0xcd/0x1e0<br /> entry_SYSCALL_64_after_hwframe+0x77/0x7f<br /> <br /> Since an instance of &amp;#39;struct kiocb&amp;#39; may be passed from the block layer<br /> with &amp;#39;private&amp;#39; field uninitialized, introduce &amp;#39;ocfs2_iocb_init_rw_locked()&amp;#39;<br /> and use it from where &amp;#39;ocfs2_dio_end_io()&amp;#39; might take care, i.e. in<br /> &amp;#39;ocfs2_file_read_iter()&amp;#39; and &amp;#39;ocfs2_file_write_iter()&amp;#39;.