bisecting cause commit starting from 2c523b344dfa65a3738e7039832044aa133c75fb
building syzkaller on 35f53e457420e79fa28e3260cdbbf9f37b9f97e4
testing commit 2c523b344dfa65a3738e7039832044aa133c75fb with gcc (GCC) 8.1.0
kernel signature: 6a3228e2757244b804a8761ddf134e124fb5bb9db2279ad31e801dd84aaccf31
run #0: crashed: KASAN: use-after-free Read in route4_get
run #1: crashed: WARNING: ODEBUG bug in route4_change
run #2: crashed: WARNING: ODEBUG bug in route4_change
run #3: crashed: WARNING: ODEBUG bug in route4_change
run #4: crashed: KASAN: use-after-free Read in route4_get
run #5: crashed: WARNING: ODEBUG bug in route4_change
run #6: crashed: WARNING: ODEBUG bug in route4_change
run #7: crashed: KASAN: use-after-free Read in route4_get
run #8: crashed: KASAN: use-after-free Read in route4_get
run #9: crashed: WARNING: ODEBUG bug in route4_change
testing release v5.5
testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.1.0
kernel signature: 1a9a8e95d7ce6a00589ae08b4e888fe269b570151b92ed30b0cd9eac35d22f49
run #0: crashed: WARNING: ODEBUG bug in route4_change
run #1: crashed: WARNING: ODEBUG bug in route4_change
run #2: crashed: WARNING: ODEBUG bug in route4_change
run #3: crashed: KASAN: use-after-free Read in route4_get
run #4: crashed: WARNING: ODEBUG bug in route4_change
run #5: crashed: WARNING: ODEBUG bug in route4_change
run #6: crashed: WARNING: ODEBUG bug in route4_change
run #7: crashed: WARNING: ODEBUG bug in route4_change
run #8: crashed: WARNING: ODEBUG bug in route4_change
run #9: crashed: WARNING: ODEBUG bug in route4_change
testing release v5.4
testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 with gcc (GCC) 8.1.0
kernel signature: e45124b087bd4bd55aab54fb0b4d2e1f6aaa44d70be8637cddcb465c108af5b9
all runs: crashed: WARNING: ODEBUG bug in route4_change
testing release v5.3
testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 with gcc (GCC) 8.1.0
kernel signature: ba021d3d577e199c01278d66c6f84478a2931ff7e59bbde91bffb0a29237d86f
all runs: crashed: WARNING: ODEBUG bug in tcf_queue_work
testing release v5.2
testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 with gcc (GCC) 8.1.0
kernel signature: e3f7e3cad9e5afce22e48ed026d281803b8196a01272f6c192ba5968c4d524bc
all runs: crashed: WARNING: ODEBUG bug in tcf_queue_work
testing release v5.1
testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd with gcc (GCC) 8.1.0
kernel signature: bb1602325806a840d458444eecf080b5f1d554736ff59dce7cfbe9595673bc3c
all runs: crashed: WARNING: ODEBUG bug in tcf_queue_work
testing release v5.0
testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 with gcc (GCC) 8.1.0
kernel signature: 9fbd24d9da8bb96c33ce1104230e80364bada628679f375755667fdac7fdd8d9
run #0: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #1: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #2: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #3: crashed: WARNING: locking bug in corrupted
run #4: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #5: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #6: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #7: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #8: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #9: crashed: WARNING: ODEBUG bug in tcf_queue_work
testing release v4.20
testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be with gcc (GCC) 8.1.0
kernel signature: 2fe7ded656228df754b59c19da4261263d14350dce52c0c6c558f6c527313964
run #0: crashed: WARNING: ODEBUG bug in __route4_delete_filter
run #1: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #2: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #3: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #4: crashed: KASAN: use-after-free Read in route4_get
run #5: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #6: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #7: crashed: KASAN: use-after-free Read in route4_get
run #8: crashed: KASAN: use-after-free Read in route4_get
run #9: crashed: WARNING: ODEBUG bug in tcf_queue_work
testing release v4.19
testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d with gcc (GCC) 8.1.0
kernel signature: 690f731b97d6cd56e57711319892993f148b931ab87170cbfbf371b94d5c363c
run #0: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #1: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #2: crashed: KASAN: use-after-free Read in route4_get
run #3: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #4: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #5: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #6: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #7: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #8: crashed: WARNING: ODEBUG bug in tcf_queue_work
run #9: crashed: WARNING: ODEBUG bug in tcf_queue_work
testing release v4.18
testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0
kernel signature: 23ab1e8adadbe8ed65649ea2f3007990bdb8e51a7ca4fcc7147a45c92aa176d5
all runs: crashed: WARNING: ODEBUG bug in tcf_queue_work
testing release v4.17
testing commit 29dcea88779c856c7dc92040a0c01233263101d4 with gcc (GCC) 8.1.0
kernel signature: cb091d8e0f07898ad3e27ede1c699974491697bb61e30a8a8db0efd1b0c250d7
all runs: crashed: WARNING: ODEBUG bug in route4_change
testing release v4.16
testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0
kernel signature: 049ee7ffd453f809c8b7e85e9a6fbb05b358a7cbd06cff9dc358f408f23fffd5
run #0: crashed: WARNING: ODEBUG bug in route4_change
run #1: crashed: WARNING: ODEBUG bug in route4_change
run #2: crashed: WARNING: ODEBUG bug in route4_change
run #3: crashed: KASAN: use-after-free Read in route4_get
run #4: crashed: WARNING: ODEBUG bug in route4_change
run #5: crashed: KASAN: use-after-free Read in route4_get
run #6: crashed: WARNING: ODEBUG bug in route4_change
run #7: crashed: KASAN: use-after-free Read in route4_get
run #8: crashed: WARNING: ODEBUG bug in route4_change
run #9: crashed: WARNING: ODEBUG bug in route4_change
testing release v4.15
testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0
kernel signature: 3bc67a265b4504e6dfb1a3f82b44ccddc036b715fe8325b7742f595c72a69686
run #0: crashed: WARNING: ODEBUG bug in route4_change
run #1: crashed: WARNING: ODEBUG bug in route4_change
run #2: crashed: WARNING: ODEBUG bug in route4_change
run #3: crashed: KASAN: use-after-free Read in route4_get
run #4: crashed: KASAN: use-after-free Read in route4_get
run #5: crashed: KASAN: use-after-free Read in route4_get
run #6: crashed: WARNING: ODEBUG bug in route4_change
run #7: crashed: WARNING: ODEBUG bug in route4_change
run #8: crashed: KASAN: use-after-free Read in route4_get
run #9: crashed: WARNING: ODEBUG bug in route4_change
testing release v4.14
testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0
kernel signature: e9013360c1b3f48dada67898d4e25de748b156eeaf4f02564dc696c8689527f3
run #0: crashed: WARNING: ODEBUG bug in route4_change
run #1: crashed: WARNING: ODEBUG bug in route4_change
run #2: crashed: WARNING: ODEBUG bug in route4_change
run #3: crashed: WARNING: ODEBUG bug in route4_change
run #4: crashed: WARNING: ODEBUG bug in route4_change
run #5: crashed: KASAN: use-after-free Read in route4_get
run #6: crashed: KASAN: use-after-free Read in route4_get
run #7: crashed: WARNING: ODEBUG bug in route4_change
run #8: crashed: WARNING: ODEBUG bug in route4_change
run #9: crashed: KASAN: use-after-free Read in route4_get
testing release v4.13
testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0
kernel signature: 0de0a8c1261d1b1d7c381239637a30d2fc95e7eb389fcdc3130148b54242c06c
run #0: crashed: KASAN: use-after-free Read in route4_get
run #1: crashed: WARNING: ODEBUG bug in route4_change
run #2: crashed: KASAN: use-after-free Read in route4_get
run #3: crashed: KASAN: use-after-free Read in route4_get
run #4: crashed: KASAN: use-after-free Read in route4_get
run #5: crashed: WARNING: ODEBUG bug in route4_change
run #6: crashed: KASAN: use-after-free Read in route4_get
run #7: crashed: WARNING: ODEBUG bug in route4_change
run #8: crashed: WARNING: ODEBUG bug in route4_change
run #9: crashed: WARNING: ODEBUG bug in route4_change
testing release v4.12
testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0
kernel signature: 88700b016f97b4a68e58774c315b6c407b6b37c5255c1acbfd31d20d064b3194
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: 40da3b2aaf7644bbae1b07d1e7fa4c7b4ee5b49b6438c732bdc8e4dfdf2589ed
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: 2cf7bc85b83cb15a33d2c47a0409d05c5f72ad4bd1e4dbdf3a76839ada9c6e64
run #0: crashed: KASAN: use-after-free Read in route4_get
run #1: crashed: KASAN: use-after-free Read in route4_get
run #2: crashed: WARNING: ODEBUG bug in route4_change
run #3: crashed: KASAN: use-after-free Read in route4_get
run #4: crashed: KASAN: use-after-free Read in route4_get
run #5: crashed: WARNING: ODEBUG bug in route4_change
run #6: crashed: WARNING: ODEBUG bug in route4_change
run #7: crashed: KASAN: use-after-free Read in route4_get
run #8: crashed: WARNING: ODEBUG bug in route4_change
run #9: crashed: WARNING: ODEBUG bug in route4_change
testing release v4.9
testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0
kernel signature: 219aa6c0c33467abca3cdd5188fb6981658edc45aca452b3621381f40cfc0ed3
run #0: crashed: KASAN: use-after-free Read in route4_get
run #1: crashed: KASAN: use-after-free Read in route4_get
run #2: crashed: KASAN: use-after-free Read in route4_get
run #3: crashed: KASAN: use-after-free Read in route4_get
run #4: crashed: KASAN: use-after-free Read in route4_get
run #5: crashed: KASAN: use-after-free Read in route4_get
run #6: crashed: WARNING: ODEBUG bug in route4_change
run #7: crashed: KASAN: use-after-free Read in route4_get
run #8: crashed: KASAN: use-after-free Read in route4_get
run #9: crashed: KASAN: use-after-free Read in route4_get
testing release v4.8
testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0
kernel signature: c7553f987953ecafcc13e1a0fe98d05a5b860888eaaf7a1dc5899ee044504722
run #0: crashed: WARNING: ODEBUG bug in route4_change
run #1: crashed: WARNING: ODEBUG bug in route4_change
run #2: crashed: KASAN: use-after-free Read in route4_get
run #3: crashed: KASAN: use-after-free Read in route4_get
run #4: crashed: KASAN: use-after-free Read in route4_get
run #5: crashed: KASAN: use-after-free Read in route4_get
run #6: crashed: KASAN: use-after-free Read in route4_get
run #7: crashed: KASAN: use-after-free Read in route4_get
run #8: crashed: KASAN: use-after-free Read in route4_get
run #9: crashed: KASAN: use-after-free Read in route4_get
testing release v4.7
testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0
kernel signature: eeb11859febb55376185945e8c1d5964c29db99fcd0eb10dd48535dd29a24cb1
run #0: crashed: WARNING: ODEBUG bug in route4_change
run #1: crashed: KASAN: use-after-free Read in route4_get
run #2: crashed: KASAN: use-after-free Read in route4_get
run #3: crashed: KASAN: use-after-free Read in route4_get
run #4: crashed: KASAN: use-after-free Read in route4_get
run #5: crashed: KASAN: use-after-free Read in route4_get
run #6: crashed: KASAN: use-after-free Read in route4_get
run #7: crashed: WARNING: ODEBUG bug in route4_change
run #8: crashed: KASAN: use-after-free Read in route4_get
run #9: crashed: WARNING: ODEBUG bug in route4_change
testing release v4.6
testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0
kernel signature: 9f8f53d879baef1751e0888f94aed4bf3cc99aaa7594cc3d14b96ba61c61606a
all runs: crashed: WARNING in sysfs_warn_dup
revisions tested: 22, total time: 3h26m55.776271559s (build: 2h8m18.087374326s, test: 1h16m13.049874839s)
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
IPv6: ADDRCONF(NETDEV_UP): hsr_slave_1: link is not ready
bond0: Enslaving bond_slave_0 as an active interface with an up link
bond0: Enslaving bond_slave_1 as an active interface with an up link
------------[ cut here ]------------
WARNING: CPU: 1 PID: 7375 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: 7375 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 ffff8800b4a76fb0 ffffffff82c74fc6 ffffffff85c81040
 ffff8800b4a77088 ffffffff85d2bac0 ffffffff81922ccb ffff8800b4a77078
 ffffffff8160cf4e 0000000041b58ab3 ffffffff868f1f61 ffffffff8160cd9f
Call Trace:
 [<ffffffff82c74fc6>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff82c74fc6>] dump_stack+0xe6/0x120 lib/dump_stack.c:51
 [<ffffffff8160cf4e>] panic+0x1af/0x348 kernel/panic.c:152
 [<ffffffff8133960d>] __warn+0x18d/0x1b0 kernel/panic.c:504
 [<ffffffff813396c2>] warn_slowpath_fmt+0x92/0xb0 kernel/panic.c:527
 [<ffffffff81922ccb>] sysfs_warn_dup+0x7b/0xa0 fs/sysfs/dir.c:30
 [<ffffffff81923561>] sysfs_do_create_link_sd.isra.2+0xd1/0xf0 fs/sysfs/symlink.c:51
 [<ffffffff819235c3>] sysfs_do_create_link fs/sysfs/symlink.c:80 [inline]
 [<ffffffff819235c3>] sysfs_create_link+0x43/0xb0 fs/sysfs/symlink.c:92
 [<ffffffff83547c79>] device_add_class_symlinks drivers/base/core.c:891 [inline]
 [<ffffffff83547c79>] device_add+0x689/0x1360 drivers/base/core.c:1086
 [<ffffffff83548cb8>] device_create_groups_vargs+0x1c8/0x220 drivers/base/core.c:1709
 [<ffffffff83548db8>] device_create_vargs drivers/base/core.c:1749 [inline]
 [<ffffffff83548db8>] device_create+0x88/0xa0 drivers/base/core.c:1785
 [<ffffffff838e6c74>] macvtap_device_event+0x1c4/0x2a0 drivers/net/macvtap.c:1298
 [<ffffffff8139f90b>] notifier_call_chain+0x8b/0x170 kernel/notifier.c:93
 [<ffffffff8139fa11>] __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 [<ffffffff8139fa11>] raw_notifier_call_chain+0x11/0x20 kernel/notifier.c:401
 [<ffffffff84941897>] call_netdevice_notifiers_info+0x47/0x80 net/core/dev.c:1643
 [<ffffffff849675ea>] call_netdevice_notifiers net/core/dev.c:1659 [inline]
 [<ffffffff849675ea>] register_netdevice+0x88a/0xce0 net/core/dev.c:7027
 [<ffffffff838df9c9>] macvlan_common_newlink+0x8b9/0x1090 drivers/net/macvlan.c:1316
 [<ffffffff838e582f>] macvtap_newlink+0xbf/0x110 drivers/net/macvtap.c:471
 [<ffffffff8499494b>] rtnl_newlink+0xd4b/0x1230 net/core/rtnetlink.c:2466
 [<ffffffff8498fcf2>] rtnetlink_rcv_msg+0x222/0x680 net/core/rtnetlink.c:3513
 [<ffffffff84b198d2>] netlink_rcv_skb+0x242/0x350 net/netlink/af_netlink.c:2277
 [<ffffffff8498fac5>] rtnetlink_rcv+0x25/0x30 net/core/rtnetlink.c:3519
 [<ffffffff84b184d5>] netlink_unicast_kernel net/netlink/af_netlink.c:1214 [inline]
 [<ffffffff84b184d5>] netlink_unicast+0x455/0x660 net/netlink/af_netlink.c:1240
 [<ffffffff84b18f73>] netlink_sendmsg+0x893/0xb40 net/netlink/af_netlink.c:1786
 [<ffffffff848f1815>] sock_sendmsg_nosec net/socket.c:612 [inline]
 [<ffffffff848f1815>] sock_sendmsg+0xb5/0xf0 net/socket.c:622
 [<ffffffff848f27e9>] SYSC_sendto+0x1c9/0x300 net/socket.c:1648
 [<ffffffff848f4ad9>] SyS_sendto+0x9/0x10 net/socket.c:1616
 [<ffffffff85b9b640>] entry_SYSCALL_64_fastpath+0x23/0xc1
Kernel Offset: disabled