================================================================== BUG: KASAN: slab-use-after-free in tty_write_room+0x7d/0x90 drivers/tty/tty_ioctl.c:68 Read of size 8 at addr ffff888070c4f020 by task aoe_tx0/1419 CPU: 2 UID: 0 PID: 1419 Comm: aoe_tx0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1a0 mm/kasan/report.c:595 tty_write_room+0x7d/0x90 drivers/tty/tty_ioctl.c:68 handle_tx+0x14a/0x620 drivers/net/caif/caif_serial.c:212 __netdev_start_xmit include/linux/netdevice.h:5273 [inline] netdev_start_xmit include/linux/netdevice.h:5282 [inline] xmit_one net/core/dev.c:3866 [inline] dev_hard_start_xmit+0x127/0x6c0 net/core/dev.c:3882 __dev_queue_xmit+0x6dd/0x46f0 net/core/dev.c:4832 dev_queue_xmit include/linux/netdevice.h:3381 [inline] tx+0xc4/0x130 drivers/block/aoe/aoenet.c:62 kthread+0x1d8/0x3c0 drivers/block/aoe/aoecmd.c:1241 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 21295: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] alloc_tty_struct+0x96/0x8c0 drivers/tty/tty_io.c:3102 tty_init_dev.part.0+0x20/0x470 drivers/tty/tty_io.c:1400 tty_init_dev include/linux/err.h:78 [inline] tty_open_by_driver drivers/tty/tty_io.c:2073 [inline] tty_open+0xa63/0xfa0 drivers/tty/tty_io.c:2120 chrdev_open+0x234/0x6a0 fs/char_dev.c:414 do_dentry_open+0x73e/0x1570 fs/open.c:962 vfs_open+0x82/0x3f0 fs/open.c:1094 do_open fs/namei.c:4637 [inline] path_openat+0x21dc/0x3120 fs/namei.c:4796 do_filp_open+0x1f7/0x420 fs/namei.c:4823 do_sys_openat2+0x12e/0x220 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_compat_sys_openat fs/open.c:1498 [inline] __se_compat_sys_openat fs/open.c:1496 [inline] __ia32_compat_sys_openat+0x12d/0x210 fs/open.c:1496 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xde/0x660 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 19082: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6674 [inline] kfree+0x1c7/0x690 mm/slub.c:6882 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Last potentially related work creation: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556 insert_work+0x36/0x230 kernel/workqueue.c:2180 __queue_work+0x96f/0x10f0 kernel/workqueue.c:2335 queue_work_on+0x180/0x1e0 kernel/workqueue.c:2386 kref_put include/linux/kref.h:65 [inline] tty_kref_put drivers/tty/tty_io.c:1557 [inline] tty_kref_put drivers/tty/tty_io.c:1554 [inline] release_tty+0x4f3/0x5f0 drivers/tty/tty_io.c:1593 tty_release_struct+0xb7/0xe0 drivers/tty/tty_io.c:1692 tty_release+0xd7a/0x1300 drivers/tty/tty_io.c:1852 __fput+0x3ff/0xb40 fs/file_table.c:468 task_work_run+0x150/0x240 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x829/0x2a30 kernel/exit.c:971 do_group_exit+0xd5/0x2a0 kernel/exit.c:1112 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034 arch_do_signal_or_restart+0x91/0x770 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x86/0x4b0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_int80_emulation+0x39b/0x470 arch/x86/entry/syscall_32.c:175 asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:621 The buggy address belongs to the object at ffff888070c4f000 which belongs to the cache kmalloc-cg-2k of size 2048 The buggy address is located 32 bytes inside of freed 2048-byte region [ffff888070c4f000, ffff888070c4f800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x70c48 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88804729e381 anon flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000040 ffff88801b84c140 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 00000000f5000000 ffff88804729e381 head: 04fff00000000040 ffff88801b84c140 0000000000000000 dead000000000001 head: 0000000000000000 0000000000080008 00000000f5000000 ffff88804729e381 head: 04fff00000000003 ffffea0001c31201 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 631, tgid 630 (syz.1.3852), ts 952252617929, free_ts 952215360264 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1e1/0x250 mm/page_alloc.c:1884 prep_new_page mm/page_alloc.c:1892 [inline] get_page_from_freelist+0xe3d/0x2e10 mm/page_alloc.c:3945 __alloc_frozen_pages_noprof+0x26c/0x2410 mm/page_alloc.c:5240 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c4/0x440 mm/slub.c:3302 ___slab_alloc+0xda3/0x1ca0 mm/slub.c:4656 __slab_alloc.isra.0+0x63/0x110 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __kmalloc_cache_noprof+0x531/0x810 mm/slub.c:5775 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] ipv6_add_dev+0x1c9/0x1520 net/ipv6/addrconf.c:388 addrconf_notify+0x563/0x19c0 net/ipv6/addrconf.c:3650 notifier_call_chain+0x99/0x3b0 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2243 call_netdevice_notifiers_extack net/core/dev.c:2281 [inline] call_netdevice_notifiers net/core/dev.c:2295 [inline] register_netdevice+0x16b9/0x21d0 net/core/dev.c:11444 register_netdev+0x34/0x50 net/core/dev.c:11522 ip6_tnl_init_net+0x2ff/0x480 net/ipv6/ip6_tunnel.c:2307 ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137 page last free pid 631 tgid 630 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0x822/0x1130 mm/page_alloc.c:2973 discard_slab mm/slub.c:3346 [inline] __put_partials+0x127/0x160 mm/slub.c:3886 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x8a/0xb0 mm/kasan/common.c:406 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5657 [inline] __kmalloc_node_track_caller_noprof+0x357/0x9d0 mm/slub.c:5768 __kmemdup_nul mm/util.c:64 [inline] kstrdup+0x51/0xe0 mm/util.c:84 kstrdup_const+0x63/0x80 mm/util.c:104 __kernfs_new_node+0x9b/0x960 fs/kernfs/dir.c:633 kernfs_new_node+0x11b/0x1a0 fs/kernfs/dir.c:718 __kernfs_create_file+0x53/0x350 fs/kernfs/file.c:1057 sysfs_add_file_mode_ns+0x207/0x3c0 fs/sysfs/file.c:313 create_files fs/sysfs/group.c:82 [inline] internal_create_group+0x593/0xf40 fs/sysfs/group.c:189 internal_create_groups+0x9d/0x150 fs/sysfs/group.c:229 setup_gid_attrs drivers/infiniband/core/sysfs.c:1162 [inline] ib_setup_port_attrs+0x41f/0x600 drivers/infiniband/core/sysfs.c:1439 add_one_compat_dev+0x5b3/0x820 drivers/infiniband/core/device.c:1005 Memory state around the buggy address: ffff888070c4ef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888070c4ef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888070c4f000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888070c4f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888070c4f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================