bisecting cause commit starting from 9f01828e9e1655836fea88d0c8225d648850b33a building syzkaller on 5d7b90f1af2e3bf33992b75e7fcf0bab6bf49bd6 testing commit 9f01828e9e1655836fea88d0c8225d648850b33a with gcc (GCC) 8.1.0 kernel signature: 3864c80faf5f516be4086dea819be87adf28708c8f5014333d410d0351a349b0 all runs: crashed: possible deadlock in n_tty_receive_buf_common testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.1.0 kernel signature: debe55220454cc1a5691cdcb90500b737bf0e1254b27efb38959fa5bdf4b431c all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0 kernel signature: 57580bb8b6959482d122e598471ec352c8bc9bf678bf2c1d83a3b25b4785adbc all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0 kernel signature: f5d589b106b8ba6d31f1ec7b9fc9a33dcdf530410ee85dd9aff0ad1e39303c5e all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0 kernel signature: 67e5d31b853b21a7cf925898ba246769a1779aea76cbed3caaf75f9eb64881b7 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 kernel signature: db89fe488fe14be6deda9d64b00e9be5b9fa1de90c261c1564e6ad61cbf75b68 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 kernel signature: ba6e8744c6ea73036960361b0e997bafe9ac197e1cbde351c738c51e9e6b12ec all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 kernel signature: c6e4dcd65d5b95d4f95dde50ae511774595f5bf8c4137df10d6afea467c23202 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 kernel signature: 7b7e8060c28c53f7565c1c04be797671494a2c3f9fc585f355d3b57b9d7b731e run #0: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #1: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #2: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #3: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #4: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #5: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #6: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #7: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #8: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #9: boot failed: KASAN: use-after-free Read in dd_has_work testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 kernel signature: 5cb5f119249035d98ac5a2b3da5a890c8f6d2ec412d7aba97f26da8e89f87f75 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0 kernel signature: 2ee6884018532ad1fcdbae6930f1e9f55e8ac5f5923655effcaf13b9c9aa69c5 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 kernel signature: fa08b7dbc71855c25c24b7188de880df346b3a76a0a4ecd2e3b5ec7329de46d4 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: 77cedd51e687fbcd5b8e195e9582d8f1fc3258e1931e6cb9ff6666ba064e4276 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: 25257f64388a9354d5a6d5d6af9b4e359416828171cf191e5c8696482c1bbcfa all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: d1b7eb6a76586e58d20217c4316b4d4d068f5078822f0fe3ac476f6a72c0eda0 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0 kernel signature: bcbd088b50b6cc19f9e3f55b092d2e8bc3c7926a871ff4c4b7dd38da7dd05e1b all runs: crashed: BUG: sleeping function called from invalid context in tap_get_minor testing release v4.11 testing commit a351e9b9fc24e982ec2f0e76379a49826036da12 with gcc (GCC) 7.3.0 kernel signature: 4bce7090286a38fa6561f05800959809cf27fccbffdeea48020bf0adc9f42ae1 all runs: crashed: BUG: sleeping function called from invalid context in tap_get_minor testing release v4.10 testing commit c470abd4fde40ea6a0846a2beab642a578c0b8cd with gcc (GCC) 5.5.0 kernel signature: 20c1070cc3ecff73d1d2e196673be126d9107f55896496d7835bc7c23cc03494 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 kernel signature: fa0636e7d073552ad9fbb06e3471368ecf454c5511f9be46e369f32014e87aba all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 kernel signature: 2f7250c9e7f85bf95bc1be7dc9d3d73726dd858f0f70103fab238e3736ed7b39 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 kernel signature: 5b4d0265550e1a3b28a496c2d3483454e1700fae8c9d997d24b82d4e5db984d0 all runs: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 kernel signature: 0fda8d3a598900a0ca8d420ef91cfc2e195b8abdb7020e26aadd0e2966311bba all runs: crashed: WARNING in sysfs_warn_dup revisions tested: 22, total time: 3h28m57.673313012s (build: 2h0m0.816924898s, test: 1h26m16.876183795s) the crash already happened on the oldest tested release commit msg: Linux 4.6 crash: WARNING in sysfs_warn_dup IPv6: ADDRCONF(NETDEV_UP): hsr_slave_0: link is not ready bond0: Enslaving bond_slave_1 as an active interface with an up link IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready ------------[ cut here ]------------ WARNING: CPU: 0 PID: 7360 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x7b/0xa0 fs/sysfs/dir.c:30 sysfs: cannot create duplicate filename '/class/macvtap/tap50' Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 7360 Comm: syz-executor.0 Not tainted 4.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 1ffffffff0d95756 ffff8800b9edefb0 ffffffff82c74fc6 ffffffff85c81040 ffff8800b9edf088 ffffffff85d2bac0 ffffffff81922ccb ffff8800b9edf078 ffffffff8160cf4e 0000000041b58ab3 ffffffff868f2161 ffffffff8160cd9f Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xe6/0x120 lib/dump_stack.c:51 [] panic+0x1af/0x348 kernel/panic.c:152 [] __warn+0x18d/0x1b0 kernel/panic.c:504 [] warn_slowpath_fmt+0x92/0xb0 kernel/panic.c:527 [] sysfs_warn_dup+0x7b/0xa0 fs/sysfs/dir.c:30 [] sysfs_do_create_link_sd.isra.2+0xd1/0xf0 fs/sysfs/symlink.c:51 [] sysfs_do_create_link fs/sysfs/symlink.c:80 [inline] [] sysfs_create_link+0x43/0xb0 fs/sysfs/symlink.c:92 [] device_add_class_symlinks drivers/base/core.c:891 [inline] [] device_add+0x689/0x1360 drivers/base/core.c:1086 [] device_create_groups_vargs+0x1c8/0x220 drivers/base/core.c:1709 [] device_create_vargs drivers/base/core.c:1749 [inline] [] device_create+0x88/0xa0 drivers/base/core.c:1785 [] macvtap_device_event+0x1c4/0x2a0 drivers/net/macvtap.c:1298 [] notifier_call_chain+0x8b/0x170 kernel/notifier.c:93 [] __raw_notifier_call_chain kernel/notifier.c:394 [inline] [] raw_notifier_call_chain+0x11/0x20 kernel/notifier.c:401 [] call_netdevice_notifiers_info+0x47/0x80 net/core/dev.c:1643 [] call_netdevice_notifiers net/core/dev.c:1659 [inline] [] register_netdevice+0x88a/0xce0 net/core/dev.c:7027 [] macvlan_common_newlink+0x8b9/0x1090 drivers/net/macvlan.c:1316 [] macvtap_newlink+0xbf/0x110 drivers/net/macvtap.c:471 [] rtnl_newlink+0xd4b/0x1230 net/core/rtnetlink.c:2466 [] rtnetlink_rcv_msg+0x222/0x680 net/core/rtnetlink.c:3513 [] netlink_rcv_skb+0x242/0x350 net/netlink/af_netlink.c:2277 [] rtnetlink_rcv+0x25/0x30 net/core/rtnetlink.c:3519 [] netlink_unicast_kernel net/netlink/af_netlink.c:1214 [inline] [] netlink_unicast+0x455/0x660 net/netlink/af_netlink.c:1240 [] netlink_sendmsg+0x893/0xb40 net/netlink/af_netlink.c:1786 [] sock_sendmsg_nosec net/socket.c:612 [inline] [] sock_sendmsg+0xb5/0xf0 net/socket.c:622 [] SYSC_sendto+0x1c9/0x300 net/socket.c:1648 [] SyS_sendto+0x9/0x10 net/socket.c:1616 [] entry_SYSCALL_64_fastpath+0x23/0xc1 Kernel Offset: disabled