bisecting cause commit starting from d96d875ef5dd372f533059a44f98e92de9cf0d42 building syzkaller on 8eda0b957e5b39c0c525e74f51d6b39ab8c5b1ac testing commit d96d875ef5dd372f533059a44f98e92de9cf0d42 with gcc (GCC) 8.1.0 kernel signature: f49047f02abe12d428665aefed1c49bc7abd62dc all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0 kernel signature: 28682b77af0c6abfae69c78e652ec5277f08389b all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0 kernel signature: 0178f07a8ae8e76a80e1f0034c38067acada606c all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0 kernel signature: d6c22df6e8671d3323280cd550e9226ca6f4c1ca all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0 kernel signature: 8bf070ca8dc25fb38d181b66ece773898688e7b1 all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0 kernel signature: 1cca3d2c4b709ecde048551ec9a8ba88bf794323 all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0 kernel signature: d6ef23cfef6fa2ddc3b9e5dfec5e33f27075fffc all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0 kernel signature: 4b4a633e4ff756d684b16a54ef0f8e6309a16a90 all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 kernel signature: 6460c34941d849cf76d125e7385d8df754654d6a all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0 kernel signature: 19cb9bfb8511c7ea804c3c2f40d057d1a9dd1ea3 all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 kernel signature: c124229b1f4ed11465857c59e7632b5e50e0cfcb all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: e02a1671deef4b46e344503e34e3387c4450bf23 all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: 0e8fb444e771df6bb2072d36b08d3464a6ee5b73 all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: c94f9682318d694527063a66dae1bd04b49a051c all runs: crashed: KASAN: slab-out-of-bounds Read in __nla_put_nohdr testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0 kernel signature: 54fa126fd3b76c7ead861296ee64cb273c98002c 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: 34a32586d9315c80737c3e6f6cccb155aaed43ac 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: e5ecfac253b4fedf0bae2c2ab9f713e7811af370 all runs: crashed: KASAN: slab-out-of-bounds Read in nla_put_nohdr testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 kernel signature: 474443a0c48ce6ef021ec1681dfc4c0b365d15e6 all runs: crashed: KASAN: slab-out-of-bounds Read in nla_put_nohdr testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 kernel signature: df2252fb02bba256d380a81c2d791c4ba01271e9 all runs: crashed: KASAN: slab-out-of-bounds Read in nla_put_nohdr testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 kernel signature: c59580235b639cf0addd39d6b7d6c648552aa30a all runs: crashed: KASAN: slab-out-of-bounds Read in nla_put_nohdr testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 kernel signature: 3fea68a3b4e612c7dd78e67bd1013c8a885dc522 all runs: crashed: WARNING in sysfs_warn_dup revisions tested: 21, total time: 3h11m18.744463333s (build: 1h51m0.758708656s, test: 1h17m3.271442569s) the crash already happened on the oldest tested release commit msg: Linux 4.6 crash: WARNING in sysfs_warn_dup bridge0: port 2(bridge_slave_1) entered blocking state bridge0: port 2(bridge_slave_1) entered disabled state device bridge_slave_1 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready ------------[ cut here ]------------ WARNING: CPU: 0 PID: 7059 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: 7059 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 1ffffffff0dd577e ffff8800b9ca6fb0 ffffffff82c7d0a6 ffffffff85e83680 ffff8800b9ca7088 ffffffff85f2e180 ffffffff8192854b ffff8800b9ca7078 ffffffff8161275e 0000000041b58ab3 ffffffff86afc32f ffffffff816125af 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