================================================================== BUG: KASAN: use-after-free in setup_rw_floppy+0x84a/0x9e0 drivers/block/floppy.c:1518 Read of size 1 at addr ffff888026a5fe35 by task kworker/u16:4/3773 CPU: 2 PID: 3773 Comm: kworker/u16:4 Not tainted 5.17.0-rc2-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Workqueue: floppy fd_timer_workfn Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x303 mm/kasan/report.c:255 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 setup_rw_floppy+0x84a/0x9e0 drivers/block/floppy.c:1518 seek_floppy drivers/block/floppy.c:1639 [inline] floppy_ready drivers/block/floppy.c:1956 [inline] floppy_ready+0x345/0x1850 drivers/block/floppy.c:1927 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 16034: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] ____kasan_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:524 kasan_kmalloc include/linux/kasan.h:270 [inline] kmem_cache_alloc_trace+0x1ea/0x4a0 mm/slab.c:3567 kmalloc include/linux/slab.h:581 [inline] raw_cmd_copyin drivers/block/floppy.c:3095 [inline] raw_cmd_ioctl drivers/block/floppy.c:3162 [inline] fd_locked_ioctl+0x100e/0x2830 drivers/block/floppy.c:3530 fd_ioctl+0x35/0x50 drivers/block/floppy.c:3557 blkdev_ioctl+0x37a/0x800 block/ioctl.c:588 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 16034: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xee/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:236 [inline] __cache_free mm/slab.c:3437 [inline] kfree+0xf6/0x290 mm/slab.c:3794 raw_cmd_free+0x8a/0x1c0 drivers/block/floppy.c:3079 raw_cmd_ioctl drivers/block/floppy.c:3182 [inline] fd_locked_ioctl+0x207e/0x2830 drivers/block/floppy.c:3530 fd_ioctl+0x35/0x50 drivers/block/floppy.c:3557 blkdev_ioctl+0x37a/0x800 block/ioctl.c:588 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0x7e/0x90 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3591 __hw_addr_flush+0x152/0x240 net/core/dev_addr_lists.c:488 dev_addr_flush+0x1d/0x50 net/core/dev_addr_lists.c:533 free_netdev+0x1f5/0x5b0 net/core/dev.c:10283 netdev_run_todo+0x8a0/0xaa0 net/core/dev.c:9964 ip_tunnel_delete_nets+0x3a4/0x5b0 net/ipv4/ip_tunnel.c:1124 ops_exit_list+0x125/0x170 net/core/net_namespace.c:173 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:597 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0x7e/0x90 mm/kasan/generic.c:348 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3591 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1705 unregister_sysctl_table fs/proc/proc_sysctl.c:1743 [inline] unregister_sysctl_table+0xc0/0x190 fs/proc/proc_sysctl.c:1718 mpls_dev_sysctl_unregister net/mpls/af_mpls.c:1441 [inline] mpls_dev_notify+0x4fb/0x8a0 net/mpls/af_mpls.c:1654 notifier_call_chain+0xb5/0x200 kernel/notifier.c:84 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1919 call_netdevice_notifiers_extack net/core/dev.c:1931 [inline] call_netdevice_notifiers net/core/dev.c:1945 [inline] unregister_netdevice_many+0x964/0x1850 net/core/dev.c:10415 ip_tunnel_delete_nets+0x39f/0x5b0 net/ipv4/ip_tunnel.c:1123 ops_exit_list+0x125/0x170 net/core/net_namespace.c:173 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:597 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff888026a5fe00 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 53 bytes inside of 128-byte region [ffff888026a5fe00, ffff888026a5fe80) The buggy address belongs to the page: page:ffffea00009a97c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26a5f flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea000083f648 ffffea0000657d48 ffff888010c40400 raw: 0000000000000000 ffff888026a5f000 0000000100000010 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 0x242220(__GFP_HIGH|__GFP_ATOMIC|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 7589, ts 856054219165, free_ts 610363186592 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 __alloc_pages_slowpath.constprop.0+0x2eb/0x20d0 mm/page_alloc.c:4934 __alloc_pages+0x412/0x500 mm/page_alloc.c:5402 __alloc_pages_node include/linux/gfp.h:572 [inline] kmem_getpages mm/slab.c:1378 [inline] cache_grow_begin+0x75/0x350 mm/slab.c:2584 cache_alloc_refill+0x27f/0x380 mm/slab.c:2957 ____cache_alloc mm/slab.c:3040 [inline] ____cache_alloc mm/slab.c:3023 [inline] __do_cache_alloc mm/slab.c:3267 [inline] slab_alloc mm/slab.c:3308 [inline] kmem_cache_alloc_trace+0x380/0x4a0 mm/slab.c:3565 kmalloc include/linux/slab.h:581 [inline] __hw_addr_create net/core/dev_addr_lists.c:58 [inline] __hw_addr_add_ex+0x22d/0x7e0 net/core/dev_addr_lists.c:116 __hw_addr_add net/core/dev_addr_lists.c:133 [inline] dev_addr_init+0x13a/0x220 net/core/dev_addr_lists.c:556 alloc_netdev_mqs+0x280/0x1070 net/core/dev.c:10180 ip6gre_init_net+0x1b6/0x630 net/ipv6/ip6_gre.c:1593 ops_init+0xaf/0x470 net/core/net_namespace.c:140 setup_net+0x554/0xbb0 net/core/net_namespace.c:330 copy_net_ns+0x318/0x760 net/core/net_namespace.c:474 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3048 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page_list+0x1a9/0xfa0 mm/page_alloc.c:3441 release_pages+0x317/0x1220 mm/swap.c:980 tlb_batch_pages_flush mm/mmu_gather.c:50 [inline] tlb_flush_mmu_free mm/mmu_gather.c:243 [inline] tlb_flush_mmu mm/mmu_gather.c:250 [inline] tlb_finish_mmu+0x165/0x8c0 mm/mmu_gather.c:341 exit_mmap+0x21b/0x670 mm/mmap.c:3180 __mmput+0x122/0x4b0 kernel/fork.c:1114 mmput+0x56/0x60 kernel/fork.c:1135 exit_mm kernel/exit.c:507 [inline] do_exit+0xa3c/0x2a30 kernel/exit.c:793 do_group_exit+0xd2/0x2f0 kernel/exit.c:935 __do_sys_exit_group kernel/exit.c:946 [inline] __se_sys_exit_group kernel/exit.c:944 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:944 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff888026a5fd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888026a5fd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888026a5fe00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888026a5fe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888026a5ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc ==================================================================