bisecting cause commit starting from 94f2630b18975bb56eee5d1a36371db967643479 building syzkaller on 2274ad39c8bee8efda31dc31ec8933d5624e8fe4 testing commit 94f2630b18975bb56eee5d1a36371db967643479 with gcc (GCC) 8.1.0 kernel signature: 78f56d7a95c8894d5bef45b7ebd19a02c6387b0d7ead0c22c13691508b40a4aa run #0: crashed: INFO: rcu detected stall in ksys_ioctl run #1: crashed: INFO: rcu detected stall in ksys_ioctl run #2: crashed: INFO: rcu detected stall in corrupted run #3: crashed: INFO: rcu detected stall in corrupted run #4: crashed: INFO: rcu detected stall in ksys_ioctl run #5: crashed: INFO: rcu detected stall in corrupted run #6: crashed: INFO: rcu detected stall in corrupted run #7: crashed: INFO: rcu detected stall in corrupted run #8: crashed: INFO: rcu detected stall in corrupted run #9: crashed: INFO: rcu detected stall in corrupted testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.1.0 kernel signature: 489ab9979f5c9a2789da81a8e34963c11253b937b9adbb8e806b36de3b0d2bf1 run #0: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #1: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #2: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #3: crashed: INFO: rcu detected stall in corrupted run #4: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #5: crashed: INFO: rcu detected stall in corrupted run #6: crashed: INFO: rcu detected stall in corrupted run #7: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #8: crashed: INFO: rcu detected stall in corrupted run #9: crashed: INFO: rcu detected stall in corrupted testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0 kernel signature: 28a957e8533da58a7a4a181a89d7f19e5763b94296139247f5f6fc36dc045913 run #0: crashed: INFO: rcu detected stall in corrupted run #1: crashed: INFO: rcu detected stall in corrupted run #2: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #3: crashed: INFO: rcu detected stall in corrupted run #4: crashed: INFO: rcu detected stall in corrupted run #5: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #6: crashed: INFO: rcu detected stall in corrupted run #7: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #8: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #9: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0 kernel signature: 9599bb62f9ca019ed03de9a7e922e3fb78c37ef51cdf34ce1ea3a9a6ac8c0b14 run #0: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #1: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #2: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #3: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #4: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #5: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #6: crashed: INFO: rcu detected stall in corrupted run #7: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #8: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #9: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0 kernel signature: 6ea9b0bae2c9e5745c384e2f248cf9e719fcb0967077b316040a6c3919ea7298 run #0: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #1: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #2: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #3: crashed: INFO: rcu detected stall in corrupted run #4: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #5: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #6: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #7: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #8: crashed: INFO: rcu detected stall in corrupted run #9: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 kernel signature: eecb7938482bc70ba0d7da7101e171a3b7d25af3e6f45f921980994881798447 run #0: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #1: crashed: INFO: rcu detected stall in corrupted run #2: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #3: crashed: INFO: rcu detected stall in corrupted run #4: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #5: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #6: crashed: INFO: rcu detected stall in corrupted run #7: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #8: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #9: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 kernel signature: 6f47d48f0fedc5f9cf8150ddfe77f715d107b550e68188fd50bd7c4b111137b3 run #0: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #1: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #2: crashed: INFO: rcu detected stall in corrupted run #3: crashed: INFO: rcu detected stall in corrupted run #4: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #5: crashed: INFO: rcu detected stall in corrupted run #6: crashed: INFO: rcu detected stall in corrupted run #7: crashed: INFO: rcu detected stall in corrupted run #8: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #9: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 kernel signature: df904d5003c4aa2bae8add300a8f281e15988a59f10606f60f1e1f74bbed3d5b run #0: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #1: crashed: INFO: rcu detected stall in corrupted run #2: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #3: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #4: crashed: INFO: rcu detected stall in corrupted run #5: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #6: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #7: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #8: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #9: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 kernel signature: 50be2649533be70d5f85dfad36d463cbf63aa4943578d78ba8e52d3dfc8df675 run #0: crashed: INFO: rcu detected stall in corrupted run #1: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #2: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #3: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #4: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #5: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #6: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #7: crashed: INFO: rcu detected stall in corrupted run #8: crashed: INFO: rcu detected stall in corrupted 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: 849db9561c7ca62c283f9bd577cd0fff6d1bf8316363c395f57e8b791b1ad633 run #0: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #1: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #2: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #3: crashed: INFO: rcu detected stall in corrupted run #4: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #5: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #6: crashed: INFO: rcu detected stall in corrupted run #7: crashed: INFO: rcu detected stall in corrupted run #8: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #9: crashed: INFO: rcu detected stall in corrupted testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0 kernel signature: 3ba22819bb00a0c48527511c18fdcfec53f257031eaa5ab803d38dbfdbf5a614 run #0: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #1: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #2: crashed: INFO: rcu detected stall in corrupted run #3: crashed: INFO: rcu detected stall in corrupted run #4: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #5: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #6: crashed: INFO: rcu detected stall in corrupted run #7: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #8: crashed: INFO: rcu detected stall in corrupted run #9: crashed: INFO: rcu detected stall in corrupted testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 kernel signature: 45102e020a07d583025f03ff71d71819b4965047d50b4badd6608f0668353ac2 run #0: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #1: crashed: INFO: rcu detected stall in corrupted run #2: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #3: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #4: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #5: crashed: INFO: rcu detected stall in corrupted run #6: crashed: INFO: rcu detected stall in corrupted run #7: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl run #8: crashed: INFO: rcu detected stall in corrupted run #9: crashed: INFO: rcu detected stall in kvm_vcpu_ioctl testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: 25b2151533ebe7a1e922806305741e726322c002d7f7d57b8a1a8cd36e454a46 run #0: crashed: WARNING in __x86_set_memory_region run #1: crashed: general protection fault in batadv_iv_ogm_queue_add run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: 33d0a535764118f5ad1e1fd6370c97590bf9624280d1746c2ab4dadb6b8f6fa5 run #0: crashed: WARNING in __x86_set_memory_region run #1: OK run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: 05e2a5c3b53eaf6944e458814b5386f7ace453c6b5d0d582db20c6214958244b run #0: crashed: WARNING: suspicious RCU usage in kvm_dev_ioctl run #1: basic kernel testing failed: failed to copy test binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "BatchMode=yes" "-o" "IdentitiesOnly=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-i" "/syzkaller/jobs/linux/workdir/image/key" "/tmp/syz-executor177329311" "root@10.128.0.157:./syz-executor177329311"]: exit status 1 ssh: connect to host 10.128.0.157 port 22: Connection timed out lost connection run #2: crashed: KASAN: use-after-free Read in vlan_device_event run #3: crashed: KASAN: use-after-free Read in vlan_device_event run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0 kernel signature: 27c3f346636c676de6d5b054602701fadc9cd52a95d129f9af0cb4093374ba55 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: 38468c7f75a0f80a06fe69ce4d5e9951f627c329bb04d8c88a4e6a746d546b07 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: becab9c5c2413773ddf143d5cf6e84abbc210e2f68086f8ba343372d03012165 run #0: crashed: KASAN: use-after-free Read in process_srcu run #1: OK run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 kernel signature: 4ed06aabfe453b40b58f7b38289c2f71888c88e13c67f4b24cc7b6669c4613e5 run #0: crashed: KASAN: use-after-free Read in process_srcu run #1: OK run #2: OK run #3: OK run #4: OK run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 kernel signature: c156ac7f70ac7877abfea5f47c80563b591b5e2de3f8aa4165de9b15cb47d55b run #0: crashed: KASAN: use-after-free Read in process_srcu run #1: crashed: KASAN: use-after-free Read in process_srcu run #2: crashed: KASAN: use-after-free Read in process_srcu run #3: crashed: KASAN: use-after-free Read in process_srcu run #4: crashed: KASAN: use-after-free Read in process_srcu run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 kernel signature: 505f73c66eb36f5b6572869a4351fb6ceb4bc36cff24834e71b22ffbd023acbd run #0: crashed: KASAN: use-after-free Read in kvm_dev_ioctl run #1: crashed: KASAN: use-after-free Read in kvm_vm_ioctl run #2: crashed: KASAN: use-after-free Read in kvm_dev_ioctl run #3: crashed: KASAN: use-after-free Read in kvm_vm_ioctl run #4: crashed: KASAN: use-after-free Read in kvm_dev_ioctl run #5: crashed: KASAN: use-after-free Read in kvm_dev_ioctl run #6: crashed: KASAN: use-after-free Read in kvm_dev_ioctl run #7: crashed: KASAN: use-after-free Read in kvm_dev_ioctl run #8: crashed: KASAN: use-after-free Read in kvm_dev_ioctl run #9: crashed: KASAN: use-after-free Read in kvm_dev_ioctl testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 kernel signature: 17b23492c258a0a8d614565c93d68f648b2a67424de1e26d1e1c89bf86151e18 all runs: crashed: WARNING in sysfs_warn_dup revisions tested: 22, total time: 4h27m58.185039764s (build: 1h53m58.705802577s, test: 2h30m59.168770216s) 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_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 IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready ------------[ cut here ]------------ WARNING: CPU: 1 PID: 7874 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: 1 PID: 7874 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 ffff8800b5296fb0 ffffffff82c74fc6 ffffffff85c81040 ffff8800b5297088 ffffffff85d2bac0 ffffffff81922ccb ffff8800b5297078 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