===================================================== BUG: KMSAN: uninit-value in vring_map_one_sg drivers/virtio/virtio_ring.c:380 [inline] BUG: KMSAN: uninit-value in virtqueue_add_split drivers/virtio/virtio_ring.c:614 [inline] BUG: KMSAN: uninit-value in virtqueue_add+0x1e86/0x65c0 drivers/virtio/virtio_ring.c:2210 vring_map_one_sg drivers/virtio/virtio_ring.c:380 [inline] virtqueue_add_split drivers/virtio/virtio_ring.c:614 [inline] virtqueue_add+0x1e86/0x65c0 drivers/virtio/virtio_ring.c:2210 virtqueue_add_sgs+0x186/0x1b0 drivers/virtio/virtio_ring.c:2244 __virtscsi_add_cmd drivers/scsi/virtio_scsi.c:471 [inline] virtscsi_add_cmd+0x838/0xad0 drivers/scsi/virtio_scsi.c:505 virtscsi_queuecommand+0x898/0xa60 drivers/scsi/virtio_scsi.c:602 scsi_dispatch_cmd drivers/scsi/scsi_lib.c:1609 [inline] scsi_queue_rq+0x4cc7/0x5a80 drivers/scsi/scsi_lib.c:1851 blk_mq_dispatch_rq_list+0x79b/0x3440 block/blk-mq.c:2037 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0x11b7/0x26e0 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0x12f/0x270 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x6e4/0xbc0 block/blk-mq.c:2250 blk_mq_flush_plug_list+0x1683/0x2b20 block/blk-mq.c:2799 blk_add_rq_to_plug+0x2c6/0x970 block/blk-mq.c:1297 blk_mq_submit_bio+0x26e8/0x3390 block/blk-mq.c:3013 __submit_bio+0x3b9/0xb60 block/blk-core.c:620 __submit_bio_noacct_mq block/blk-core.c:704 [inline] submit_bio_noacct_nocheck+0x148c/0x1800 block/blk-core.c:734 submit_bio_noacct+0x1bd8/0x27f0 block/blk-core.c:844 submit_bio+0x58a/0x5b0 block/blk-core.c:886 ext4_io_submit fs/ext4/page-io.c:378 [inline] io_submit_add_bh fs/ext4/page-io.c:419 [inline] ext4_bio_write_folio+0x1e76/0x2e40 fs/ext4/page-io.c:563 mpage_submit_folio+0x351/0x4a0 fs/ext4/inode.c:1869 mpage_map_and_submit_buffers fs/ext4/inode.c:2115 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2254 [inline] ext4_do_writepages+0x3733/0x62e0 fs/ext4/inode.c:2679 ext4_writepages+0x312/0x830 fs/ext4/inode.c:2768 do_writepages+0x427/0xc30 mm/page-writeback.c:2613 __writeback_single_inode+0x10d/0x12c0 fs/fs-writeback.c:1651 writeback_sb_inodes+0xc95/0x1e00 fs/fs-writeback.c:1947 wb_writeback+0x4df/0xea0 fs/fs-writeback.c:2127 wb_do_writeback fs/fs-writeback.c:2274 [inline] wb_workfn+0x40b/0x1940 fs/fs-writeback.c:2314 process_one_work kernel/workqueue.c:3267 [inline] process_scheduled_works+0xa81/0x1bd0 kernel/workqueue.c:3348 worker_thread+0xea5/0x1560 kernel/workqueue.c:3429 kthread+0x3e2/0x540 kernel/kthread.c:389 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Uninit was stored to memory at: memcpy_from_iter lib/iov_iter.c:73 [inline] iterate_bvec include/linux/iov_iter.h:122 [inline] iterate_and_advance2 include/linux/iov_iter.h:249 [inline] iterate_and_advance include/linux/iov_iter.h:271 [inline] __copy_from_iter lib/iov_iter.c:249 [inline] copy_page_from_iter_atomic+0x12b7/0x2ae0 lib/iov_iter.c:481 generic_perform_write+0x4c1/0xc60 mm/filemap.c:3982 ext4_buffered_write_iter+0x564/0xaa0 fs/ext4/file.c:299 ext4_file_write_iter+0x208/0x3450 __kernel_write_iter+0x64d/0xc80 fs/read_write.c:523 dump_emit_page fs/coredump.c:895 [inline] dump_user_range+0x8dc/0xee0 fs/coredump.c:956 elf_core_dump+0x57c7/0x5ae0 fs/binfmt_elf.c:2083 do_coredump+0x32d5/0x4920 fs/coredump.c:769 get_signal+0x267e/0x2d00 kernel/signal.c:2896 arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0xa6/0x160 kernel/entry/common.c:231 irqentry_exit+0x16/0x60 kernel/entry/common.c:334 sysvec_apic_timer_interrupt+0x52/0x90 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702 Uninit was created at: __alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598 alloc_pages_mpol+0x299/0x990 mm/mempolicy.c:2264 alloc_pages+0x1bf/0x1e0 mm/mempolicy.c:2335 dump_user_range+0x4a/0xee0 fs/coredump.c:940 elf_core_dump+0x57c7/0x5ae0 fs/binfmt_elf.c:2083 do_coredump+0x32d5/0x4920 fs/coredump.c:769 get_signal+0x267e/0x2d00 kernel/signal.c:2896 arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0xa6/0x160 kernel/entry/common.c:231 irqentry_exit+0x16/0x60 kernel/entry/common.c:334 sysvec_apic_timer_interrupt+0x52/0x90 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702 Bytes 0-4095 of 4096 are uninitialized Memory access of size 4096 starts at ffff888013615000 CPU: 1 PID: 3459 Comm: kworker/u8:24 Not tainted 6.9.0-syzkaller-02707-g614da38e2f7a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: writeback wb_workfn (flush-8:0) =====================================================