bridge0: port 1(bridge_slave_0) entered disabled state device bridge_slave_0 left promiscuous mode bridge0: port 1(bridge_slave_0) entered disabled state bond0: Releasing backup interface bond_slave_0 ================================================================== BUG: KASAN: use-after-free in free_netdev+0x3b0/0x420 net/core/dev.c:9219 Read of size 8 at addr ffff8880a08c13a0 by task syz-executor.0/8249 CPU: 1 PID: 8249 Comm: syz-executor.0 Not tainted 4.19.109-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 print_address_description.cold+0x7c/0x212 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report mm/kasan/report.c:412 [inline] kasan_report.cold+0x88/0x2b9 mm/kasan/report.c:396 free_netdev+0x3b0/0x420 net/core/dev.c:9219 netdev_run_todo+0x5ea/0x740 net/core/dev.c:8972 rtnl_unlock net/core/rtnetlink.c:117 [inline] rtnetlink_rcv_msg+0x460/0xaf0 net/core/rtnetlink.c:4778 netlink_rcv_skb+0x160/0x410 net/netlink/af_netlink.c:2455 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x4d7/0x6a0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x80b/0xcd0 net/netlink/af_netlink.c:1909 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:632 ___sys_sendmsg+0x803/0x920 net/socket.c:2115 __sys_sendmsg+0xec/0x1b0 net/socket.c:2153 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c849 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f8271ea0c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f8271ea16d4 RCX: 000000000045c849 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000005 RBP: 000000000076c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009f9 R14: 00000000004ccb17 R15: 000000000076c04c Allocated by task 8247: set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc mm/kasan/kasan.c:553 [inline] kasan_kmalloc+0xbf/0xe0 mm/kasan/kasan.c:531 __do_kmalloc mm/slab.c:3727 [inline] __kmalloc+0x15b/0x770 mm/slab.c:3736 kmalloc include/linux/slab.h:520 [inline] sk_prot_alloc+0x18c/0x2d0 net/core/sock.c:1466 sk_alloc+0x36/0xf50 net/core/sock.c:1520 tun_chr_open+0x7b/0x560 drivers/net/tun.c:3224 misc_open+0x372/0x4a0 drivers/char/misc.c:141 chrdev_open+0x219/0x5c0 fs/char_dev.c:423 do_dentry_open+0x4a8/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x1031/0x4200 fs/namei.c:3537 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_sys_open+0x3c0/0x500 fs/open.c:1088 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 8246: set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/kasan.c:521 __cache_free mm/slab.c:3503 [inline] kfree+0xce/0x220 mm/slab.c:3822 sk_prot_free net/core/sock.c:1503 [inline] __sk_destruct+0x579/0x780 net/core/sock.c:1583 sk_destruct+0xb9/0xf0 net/core/sock.c:1598 __sk_free+0xc2/0x2e0 net/core/sock.c:1609 sk_free+0x3b/0x50 net/core/sock.c:1620 sock_put include/net/sock.h:1707 [inline] __tun_detach+0xa04/0x1020 drivers/net/tun.c:742 tun_detach drivers/net/tun.c:754 [inline] tun_chr_close+0x10e/0x180 drivers/net/tun.c:3261 __fput+0x2cd/0x890 fs/file_table.c:278 task_work_run+0x13f/0x1b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x25a/0x2b0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a08c0d00 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 1696 bytes inside of 4096-byte region [ffff8880a08c0d00, ffff8880a08c1d00) The buggy address belongs to the page: page:ffffea0002823000 count:1 mapcount:0 mapping:ffff88812c3dcdc0 index:0x0 compound_mapcount: 0 flags: 0xfffe0000008100(slab|head) raw: 00fffe0000008100 ffffea000208cd08 ffffea0002036788 ffff88812c3dcdc0 raw: 0000000000000000 ffff8880a08c0d00 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a08c1280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a08c1300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a08c1380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a08c1400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a08c1480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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