================================================================== BUG: KASAN: slab-use-after-free in tty_write_room+0x7d/0x90 drivers/tty/tty_ioctl.c:68 Read of size 8 at addr ffff88803b8a5020 by task aoe_tx0/1421 CPU: 2 UID: 0 PID: 1421 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 tty_write_room+0x7d/0x90 drivers/tty/tty_ioctl.c:68 handle_tx+0x14f/0x630 drivers/net/caif/caif_serial.c:212 __netdev_start_xmit include/linux/netdevice.h:5248 [inline] netdev_start_xmit include/linux/netdevice.h:5257 [inline] xmit_one net/core/dev.c:3845 [inline] dev_hard_start_xmit+0x97/0x6e0 net/core/dev.c:3861 __dev_queue_xmit+0xa46/0x4330 net/core/dev.c:4763 dev_queue_xmit include/linux/netdevice.h:3365 [inline] tx+0xcc/0x190 drivers/block/aoe/aoenet.c:62 kthread+0x1e4/0x3e0 drivers/block/aoe/aoecmd.c:1241 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x855/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 11979: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 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+0x1e/0x500 drivers/tty/tty_io.c:1400 tty_init_dev include/linux/err.h:70 [inline] tty_open_by_driver drivers/tty/tty_io.c:2073 [inline] tty_open+0xa4f/0xf90 drivers/tty/tty_io.c:2120 chrdev_open+0x234/0x6a0 fs/char_dev.c:414 do_dentry_open+0x748/0x1590 fs/open.c:962 vfs_open+0x82/0x3f0 fs/open.c:1094 do_open fs/namei.c:4628 [inline] path_openat+0x2078/0x3140 fs/namei.c:4787 do_filp_open+0x20b/0x470 fs/namei.c:4814 do_sys_openat2+0x11f/0x280 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6078: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2543 [inline] slab_free mm/slub.c:6642 [inline] kfree+0x29e/0x710 mm/slub.c:6849 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3263 process_scheduled_works kernel/workqueue.c:3346 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x855/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Last potentially related work creation: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:559 insert_work+0x36/0x230 kernel/workqueue.c:2186 __queue_work+0x954/0x10f0 kernel/workqueue.c:2341 queue_work_on+0x1a4/0x1f0 kernel/workqueue.c:2392 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+0x4de/0x5d0 drivers/tty/tty_io.c:1593 tty_release_struct+0xb7/0xe0 drivers/tty/tty_io.c:1692 tty_release+0xe2d/0x1430 drivers/tty/tty_io.c:1852 __fput+0x402/0xb70 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+0x877/0x2bc0 kernel/exit.c:972 do_group_exit+0xd3/0x2a0 kernel/exit.c:1113 get_signal+0x2671/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:40 [inline] exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] irqentry_exit_to_user_mode+0x18e/0x370 kernel/entry/common.c:73 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 The buggy address belongs to the object at ffff88803b8a5000 which belongs to the cache kmalloc-cg-2k of size 2048 The buggy address is located 32 bytes inside of freed 2048-byte region [ffff88803b8a5000, ffff88803b8a5800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3b8a0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888059aef081 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b44c140 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000080008 00000000f5000000 ffff888059aef081 head: 00fff00000000040 ffff88801b44c140 0000000000000000 dead000000000001 head: 0000000000000000 0000000000080008 00000000f5000000 ffff888059aef081 head: 00fff00000000003 ffffea0000ee2801 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 5944, tgid 5944 (syz-executor), ts 54381920241, free_ts 54377451722 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845 prep_new_page mm/page_alloc.c:1853 [inline] get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3879 __alloc_frozen_pages_noprof+0x25f/0x2440 mm/page_alloc.c:5178 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3059 [inline] allocate_slab mm/slub.c:3232 [inline] new_slab+0x24a/0x360 mm/slub.c:3286 ___slab_alloc+0xee7/0x1cd0 mm/slub.c:4655 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4778 __slab_alloc_node mm/slub.c:4854 [inline] slab_alloc_node mm/slub.c:5276 [inline] __kmalloc_cache_noprof+0x477/0x770 mm/slub.c:5766 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] ipv6_add_dev+0x1c9/0x1590 net/ipv6/addrconf.c:388 addrconf_notify+0x53e/0x19b0 net/ipv6/addrconf.c:3650 notifier_call_chain+0xbc/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2229 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline] call_netdevice_notifiers net/core/dev.c:2281 [inline] register_netdevice+0x1792/0x21d0 net/core/dev.c:11332 veth_newlink+0x44d/0xa00 drivers/net/veth.c:1885 rtnl_newlink_create net/core/rtnetlink.c:3833 [inline] __rtnl_newlink net/core/rtnetlink.c:3950 [inline] rtnl_newlink+0xc19/0x1f50 net/core/rtnetlink.c:4065 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6951 page last free pid 5944 tgid 5944 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2901 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4978 [inline] slab_alloc_node mm/slub.c:5288 [inline] __kmalloc_cache_noprof+0x274/0x770 mm/slub.c:5766 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] ref_tracker_alloc+0x18e/0x5b0 lib/ref_tracker.c:271 __netdev_tracker_alloc include/linux/netdevice.h:4375 [inline] netdev_hold include/linux/netdevice.h:4404 [inline] netdev_hold include/linux/netdevice.h:4399 [inline] register_netdevice+0x15ed/0x21d0 net/core/dev.c:11318 veth_newlink+0x316/0xa00 drivers/net/veth.c:1856 rtnl_newlink_create net/core/rtnetlink.c:3833 [inline] __rtnl_newlink net/core/rtnetlink.c:3950 [inline] rtnl_newlink+0xc19/0x1f50 net/core/rtnetlink.c:4065 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6951 netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2552 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] __sys_sendto+0x4a3/0x520 net/socket.c:2222 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2225 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 Memory state around the buggy address: ffff88803b8a4f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803b8a4f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88803b8a5000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803b8a5080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88803b8a5100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================