bisecting cause commit starting from f2850dd5ee015bd7b77043f731632888887689c7 building syzkaller on 84f4fc8afc9aedba4b3afa4bb76c3df6c6352c07 testing commit f2850dd5ee015bd7b77043f731632888887689c7 with gcc (GCC) 8.1.0 kernel signature: 977883fc6dbef3429c47627257f7b74c962581d87aa744a04fb3c13debeed964 all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.1.0 kernel signature: 08fe86955a27dc34ddf04985353519f6c09c844005efbecd4741720d6d3be31e all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0 kernel signature: 8a586768af0eafb617e96c6ca340f3774b0f549762264656ea49f9dfe4d05cd7 all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0 kernel signature: 6f33a7288573628f6c283fddd6b96c886cd703cdc021fde8e8614f6fe4a7c705 all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0 kernel signature: 86cc8c0e66b7b2ab5a6bbdaf33282b880bed5e3ef80793828f551b65cf7db8bd all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 kernel signature: e4e4f8ce932ce85989b66046161df5f9ad2527039b0f695618e511abff1a4e9e all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 kernel signature: 16358aa89bc6ac4f57b2a093a3a0d745a3ee6b8e528eef5666780aedc573f522 all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 kernel signature: 35732f65e95302dd59f5672263409742068b8a1c715f99c6f5ce454f762a5acd all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 kernel signature: 9b0872101241d3d1700b73114a67d515f7daa9e431dc8f402832e0cac56ed449 all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 kernel signature: 81169506d2a89c889528b03470af6fa15e08c7455708856e261fca560f9b0fd0 all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0 kernel signature: e2263d0f6872263c8fee984f266a747f7a6aa1a33d0750967b7be8bc8fc55f2a all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 kernel signature: 8b31aeb2aab38bad017add8e991314064b3a9db96460926022559fb8a6927f76 all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: f15a5b0e772354f131b5fbcebc57b21c06a3f6219a0d4a8905c23f149418fd75 all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: af89c9109e156c442a9eaa618205e4c67f4e9635c32d7fa8ddf0d7550ed2b24a all runs: crashed: KASAN: null-ptr-deref Read in do_con_trol testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: fa4da301218b1bc3a4b90081b24218885de9c4a54e3daefb33cdae73382a473a all runs: crashed: general protection fault in do_con_trol testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0 kernel signature: 970f9ac84e99b790c97f1ae363ca9588f07ec406a519be78777abd81e5ddf05e 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: 0bbda091352eef9c9e08c4bca3424d32123266bb24d54078010e95225e10862c 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: 28d8aea4a61e30639761cd6b877d88cc0b16e75a4cdc5e9f10ede27c228dbcbb all runs: crashed: general protection fault in do_con_trol testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 kernel signature: 660584ec53ad5177829224bc8a854e0655cb668a68170f1ab0955b68f9f01003 all runs: crashed: general protection fault in do_con_trol testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 kernel signature: 95f3d2728d6a88c8c0832d25f1e648e791e77b9ae34780375f011c13a4e43671 all runs: crashed: general protection fault in do_con_trol testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 kernel signature: 401218db0e2378306bd736b5f0e2efe1dd26e73ef2867cad13601945d3243aeb all runs: crashed: general protection fault in do_con_trol testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 kernel signature: 3cd8003794a9c417c3b84effdc7504a40aaa47a7dc2e39d61e2961f36f995027 all runs: crashed: WARNING in sysfs_warn_dup revisions tested: 22, total time: 3h15m1.652375416s (build: 1h59m18.764451559s, test: 1h13m13.680019864s) the crash already happened on the oldest tested release commit msg: Linux 4.6 crash: WARNING in sysfs_warn_dup 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): hsr_slave_0: link is not ready IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready ------------[ cut here ]------------ WARNING: CPU: 0 PID: 7567 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: 7567 Comm: syz-executor.5 Not tainted 4.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 1ffffffff0d95756 ffff8800b3d46fb0 ffffffff82c74fc6 ffffffff85c81040 ffff8800b3d47088 ffffffff85d2bac0 ffffffff81922ccb ffff8800b3d47078 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