bisecting cause commit starting from 22fbc037cd32e4e6771d2271b565806cfb8c134c building syzkaller on 1a3f94087169f62f9a5832828f62b4900e98b781 testing commit 22fbc037cd32e4e6771d2271b565806cfb8c134c with gcc (GCC) 8.1.0 kernel signature: 74821f933cbdb756d3dd682c1eabd7d0b972cced73fb51ffb1b102a9da55fdff run #0: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #1: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #2: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #3: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #4: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #5: OK run #6: OK run #7: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #8: OK run #9: OK testing release v5.8 testing commit bcf876870b95592b52519ed4aafcf9d95999bc9c with gcc (GCC) 8.1.0 kernel signature: b6379a7b7cdb44dc35c0e46d7bad0f23c7b8639d37b7e93757a4cc7464a8b19d run #0: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #1: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #2: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #3: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #4: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #5: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #6: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #7: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #8: OK run #9: OK testing release v5.7 testing commit 3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162 with gcc (GCC) 8.1.0 kernel signature: b2a4ad7fd1dab9b599fdc468fa78431c7164af8d0763987ee403259bd5bb094f run #0: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #1: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #2: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #3: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #4: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #5: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #6: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #7: OK run #8: OK run #9: crashed: BUG: unable to handle kernel paging request in cfb_imageblit testing release v5.6 testing commit 7111951b8d4973bda27ff663f2cf18b663d15b48 with gcc (GCC) 8.1.0 kernel signature: 50b3a79997cf7efd3e6188db8a6648a71da7e9cd74e460d3458fd0236b81d2f7 run #0: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #1: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #2: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #3: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #4: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #5: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #6: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #7: crashed: BUG: unable to handle kernel paging request in cfb_imageblit run #8: OK run #9: crashed: BUG: unable to handle kernel paging request in cfb_imageblit testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 with gcc (GCC) 8.1.0 kernel signature: b8206f55248124582b82ebd396ae30ad20f69b050633ab8864341fcb9f6b73ad 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: ea8ccebe5f54a0f0cebe2bcbf7bbcf74f44118323a6b46cf8ee40aac6e0131a1 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: 1d1cb74777991b1688c2113391b308a5da745a7b2dccbf7049623fd5cdf659d8 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: 9c36616268c79d426c2499ca622f1625e961e3d2adb17cd286f2d66b85c389e8 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: fd4c42584e7232dbbfa0abf93565452a1254843b74a84835ed3f537ef153ace9 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: 865d59bc6415efd921e7a3cbdb77f96ef376e6e8a2ee9a79fd7af1972a7ffce9 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: 5cfa7856d9fed52940c2ce8c186ea280b72ef0671d601d9122e73b89a4b2b058 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: 997943a3f3b66e34a634b4d7b6512e6e191fcf7ecd685ec99231fa02caba0f87 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: crashed: INFO: task hung in paste_selection testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 with gcc (GCC) 8.1.0 kernel signature: 1b73a37f8854b7e4170279c3471e9a87af8c6c37734c17b708fbe91af87dd767 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: 7a4055bb17b7e73ce298bf28468bc7da65cf7a376347e653d5cb8cf080b647fb 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: crashed: INFO: task hung in tty_ldisc_hangup testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda with gcc (GCC) 8.1.0 kernel signature: b2b7b5d13e51dbbe7f66352c859edc31bd19802372ac5e2975dc71f65d303c5d 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: INFO: task hung in paste_selection run #9: crashed: INFO: task hung in paste_selection testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff with gcc (GCC) 8.1.0 kernel signature: 0b07357537d95acba977b1c2c8a0f5525116264b9eb7ef43009077f6f86199a3 run #0: crashed: BUG: unable to handle kernel paging request in cfb_imageblit 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: crashed: INFO: task hung in tty_ldisc_hangup testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 with gcc (GCC) 8.1.0 kernel signature: b10d9143facadabc0cf1b0023c138144b99209ea4205681e6749cf722e604eb3 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: crashed: INFO: task hung in tty_ldisc_hangup testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 with gcc (GCC) 8.1.0 kernel signature: 909e95a5ec81b4c5ecabf20ff5f454f9e5f92f2f9c9c8a314c0a4d8e84981f42 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: crashed: INFO: task hung in tty_ldisc_hangup testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c with gcc (GCC) 8.1.0 kernel signature: 3b49bebdbb108cc6ca4a827d38ae8084f133af6d6a112dead09936a8b8741a7e 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: 1536d4a8e26f7b633acd9f47cbc65128199bfe74c6487437748a53949780da75 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: dc3a8c72fd1850346bdf078225b0c0bcaa8c198f40459686acf4dfe4c7809d72 run #0: crashed: KASAN: use-after-free Read in n_tty_receive_buf_common run #1: crashed: BUG: unable to handle kernel paging request in cfb_imageblit 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: crashed: INFO: task hung in n_tty_receive_buf_common testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 with gcc (GCC) 5.5.0 kernel signature: e86596ad8211b1d6bfd608d9f86af39a69d5fdd2fd7deb009b1e90c90a2ed444 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: INFO: task hung in commit_echoes run #9: crashed: INFO: task hung in tty_ldisc_hangup testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 with gcc (GCC) 5.5.0 kernel signature: 2002bdbbc1ea1f674c4d3d9811c270b19fd91b1838751ff00474ead0e3f78f6b run #0: crashed: KASAN: use-after-free in n_tty_receive_buf_common at addr ADDR 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 in n_tty_receive_buf_common at addr ADDR 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: crashed: INFO: task hung in paste_selection testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e with gcc (GCC) 5.5.0 kernel signature: 9e78d1e12670d1ba292a4b0522c13457778639482b4ed3f408d38d00cf4d6f35 run #0: crashed: general protection fault in batadv_iv_ogm_queue_add run #1: crashed: general protection fault in rt6_score_route 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 v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a with gcc (GCC) 5.5.0 kernel signature: 43bf4700fff5fcf335284a15e4d362db198d5c02cb066ab56e06714c3a63d8cf all runs: crashed: WARNING in sysfs_warn_dup revisions tested: 25, total time: 4h56m28.946165077s (build: 2h22m6.39745581s, test: 2h30m24.373457869s) the crash already happened on the oldest tested release commit msg: Linux 4.6 crash: WARNING in sysfs_warn_dup IPv6: ADDRCONF(NETDEV_UP): bridge_slave_0: link is not ready IPv6: ADDRCONF(NETDEV_UP): bridge_slave_1: link is not ready IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready bond0: Enslaving bond_slave_0 as an active interface with an up link ------------[ cut here ]------------ WARNING: CPU: 1 PID: 5910 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: 5910 Comm: syz-executor.4 Not tainted 4.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000000 ffff8800b9d16fc8 ffffffff82e18b12 ffffffff85e81040 ffff8800b9d170a0 ffffffff85f2bc00 ffffffff8191bd7b 0000000000000009 ffff8800b9d17090 ffffffff8160d884 0000000041b58ab3 ffffffff86b4158a Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0x136/0x1d4 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.0+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+0x677/0x1350 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+0x8e8/0xd00 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+0x3da/0x560 net/netlink/af_netlink.c:1240 [] netlink_sendmsg+0x9bb/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 net/socket.c:1648 [inline] [] SyS_sendto+0x1ca/0x290 net/socket.c:1616 [] entry_SYSCALL_64_fastpath+0x23/0xc1 Kernel Offset: disabled