Hello, syzbot found the following issue on: HEAD commit: 7503345ac5f5 Merge tag 'block-6.13-20241207' of git://git... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15220c0f980000 kernel config: https://syzkaller.appspot.com/x/.config?x=1362a5aee630ff34 dashboard link: https://syzkaller.appspot.com/bug?extid=6b0df248918b92c33e6a compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-7503345a.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/e95a2b302e11/vmlinux-7503345a.xz kernel image: https://storage.googleapis.com/syzbot-assets/e78c0c786fb3/bzImage-7503345a.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6b0df248918b92c33e6a@xxxxxxxxxxxxxxxxxxxxxxxxx Bluetooth: hci0: command tx timeout block nbd0: Receive control failed (result -32) block nbd0: shutting down sockets ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline] BUG: KASAN: slab-use-after-free in atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline] BUG: KASAN: slab-use-after-free in recv_work+0x2280/0x25c0 drivers/block/nbd.c:961 Write of size 4 at addr ffff88803e947e78 by task kworker/u5:2/5301 CPU: 0 UID: 0 PID: 5301 Comm: kworker/u5:2 Not tainted 6.13.0-rc1-syzkaller-00337-g7503345ac5f5 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: nbd0-recv recv_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline] recv_work+0x2280/0x25c0 drivers/block/nbd.c:961 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Allocated by task 5314: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4314 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] nbd_alloc_and_init_config+0x88/0x260 drivers/block/nbd.c:1596 nbd_genl_connect+0xcba/0x1c80 drivers/block/nbd.c:2059 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0xb14/0xec0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2542 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1347 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmsg+0x269/0x350 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5301: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kfree+0x196/0x430 mm/slub.c:4746 nbd_config_put+0x67d/0x7e0 drivers/block/nbd.c:1386 recv_work+0x226a/0x25c0 drivers/block/nbd.c:960 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff88803e947e00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 120 bytes inside of freed 256-byte region [ffff88803e947e00, ffff88803e947f00) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3e947 ksm flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000000 ffff88801ac41b40 ffffea0000fb95c0 dead000000000003 raw: 0000000000000000 0000000080080008 00000001f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 17751892312, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3474 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 alloc_slab_page+0x6a/0x140 mm/slub.c:2408 allocate_slab+0x5a/0x2f0 mm/slub.c:2574 new_slab mm/slub.c:2627 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3815 __slab_alloc+0x58/0xa0 mm/slub.c:3905 __slab_alloc_node mm/slub.c:3980 [inline] slab_alloc_node mm/slub.c:4141 [inline] __do_kmalloc_node mm/slub.c:4282 [inline] __kmalloc_node_noprof+0x2ee/0x4d0 mm/slub.c:4289 __kvmalloc_node_noprof+0x72/0x190 mm/util.c:650 v4l2_ctrl_new+0x910/0x1910 drivers/media/v4l2-core/v4l2-ctrls-core.c:1931 v4l2_ctrl_new_std+0x449/0x5b0 drivers/media/v4l2-core/v4l2-ctrls-core.c:2068 handler_new_ref+0x1fe/0x940 drivers/media/v4l2-core/v4l2-ctrls-core.c:1689 v4l2_ctrl_add_handler+0x1a1/0x290 drivers/media/v4l2-core/v4l2-ctrls-core.c:2212 vivid_create_controls+0x37dd/0x4140 drivers/media/test-drivers/vivid/vivid-ctrls.c:2030 vivid_create_instance drivers/media/test-drivers/vivid/vivid-core.c:1931 [inline] vivid_probe+0x48ba/0x7cf0 drivers/media/test-drivers/vivid/vivid-core.c:2093 page_owner free stack trace missing Memory state around the buggy address: ffff88803e947d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803e947d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88803e947e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803e947e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803e947f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== --- This report is generated by a bot. 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