syzbot


WARNING in kcov_remote_start

Status: upstream: reported on 2025/06/28 15:34
Reported-by: syzbot+e64fc7c934fb30351dfe@syzkaller.appspotmail.com
First crash: 225d, last: 10h02m
Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in kcov_remote_start -1 4 395d 494d 0/3 auto-obsoleted due to no activity on 2025/04/19 19:40
upstream WARNING in kcov_remote_start (4) usb -1 107983 578d 609d 26/29 fixed on 2024/07/10 08:24
upstream WARNING in kcov_remote_start (2) usb -1 C 1153 2349d 2350d 0/29 closed as invalid on 2019/09/04 14:27
upstream WARNING in kcov_remote_start (5) wireless -1 4243 474d 574d 28/29 fixed on 2024/10/22 14:56
upstream WARNING in kcov_remote_start (3) usb -1 265513 613d 682d 25/29 fixed on 2024/06/05 13:52
upstream WARNING in kcov_remote_start usb -1 C 655 2350d 2350d 0/29 closed as invalid on 2019/09/03 16:37
upstream WARNING in kcov_remote_start (6) wireless -1 8225 now 461d 0/29 upstream: reported on 2024/11/04 21:25

Sample crash report:
team0: Device wlan1 is of different type
------------[ cut here ]------------
WARNING: CPU: 1 PID: 20876 at kernel/kcov.c:869 arch_local_irq_restore arch/x86/include/asm/irqflags.h:137 [inline]
WARNING: CPU: 1 PID: 20876 at kernel/kcov.c:869 kcov_remote_start+0x54d/0x7e0 kernel/kcov.c:887
Modules linked in:
CPU: 1 PID: 20876 Comm: syz.4.5333 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:kcov_remote_start+0x54d/0x7e0 kernel/kcov.c:869
Code: ff ff 4c 89 ff be 03 00 00 00 e8 6e 60 8e 02 e9 f0 fa ff ff e8 34 15 aa 08 f7 c3 00 02 00 00 0f 84 df fa ff ff e9 5a fc ff ff <0f> 0b e8 bc 29 aa 08 89 c0 48 c7 c7 70 b1 02 00 48 03 3c c5 80 f9
RSP: 0018:ffffc90004b1e270 EFLAGS: 00010002
RAX: 0000000080000200 RBX: 0000000000000246 RCX: 0000000000000002
RDX: dffffc0000000000 RSI: ffffffff8a8c23a0 RDI: ffffffff8adf0d20
RBP: ffffc90004b1e4d0 R08: dffffc0000000000 R09: 1ffffffff215e854
R10: dffffc0000000000 R11: fffffbfff215e855 R12: ffff8880b8f2b170
R13: ffffffff81827b9b R14: ffff88802e43bb80 R15: 0000000000000000
FS:  00007f6cccdc26c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b35603000 CR3: 0000000042f7e000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 kcov_remote_start_common include/linux/kcov.h:50 [inline]
 ieee80211_rx_list+0x504/0x2e60 net/mac80211/rx.c:5297
 ieee80211_rx_napi+0x1ae/0x3d0 net/mac80211/rx.c:5338
 ieee80211_rx include/net/mac80211.h:4849 [inline]
 ieee80211_handle_queued_frames+0x105/0x1b0 net/mac80211/main.c:317
 ieee80211_stop_device+0x27/0xa0 net/mac80211/util.c:2211
 ieee80211_do_stop+0x1724/0x1e20 net/mac80211/iface.c:750
 ieee80211_stop+0x432/0x4a0 net/mac80211/iface.c:809
 __dev_close_many+0x1d1/0x2b0 net/core/dev.c:1585
 dev_close_many+0x21f/0x400 net/core/dev.c:1610
 dev_close+0x154/0x210 net/core/dev.c:1636
 team_port_add drivers/net/team/team.c:1329 [inline]
 team_add_slave+0x181b/0x2870 drivers/net/team/team.c:2002
 do_set_master net/core/rtnetlink.c:2630 [inline]
 do_setlink+0xd3a/0x3e60 net/core/rtnetlink.c:2840
 __rtnl_newlink net/core/rtnetlink.c:3608 [inline]
 rtnl_newlink+0x177c/0x2080 net/core/rtnetlink.c:3655
 rtnetlink_rcv_msg+0x87c/0xfc0 net/core/rtnetlink.c:6150
 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1872
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x5be/0x970 net/socket.c:2518
 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2572
 __sys_sendmsg net/socket.c:2601 [inline]
 __do_sys_sendmsg net/socket.c:2610 [inline]
 __se_sys_sendmsg+0x1bb/0x2a0 net/socket.c:2608
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6ccbf9aeb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6cccdc2028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f6ccc215fa0 RCX: 00007f6ccbf9aeb9
RDX: 0000000000000000 RSI: 0000200000000600 RDI: 000000000000000e
RBP: 00007f6ccc008c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6ccc216038 R14: 00007f6ccc215fa0 R15: 00007ffe9cfc9a38
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/08 12:43 linux-6.1.y 0182cb5b74ee 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf WARNING in kcov_remote_start
2025/11/20 01:17 linux-6.1.y f6e38ae624cf 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan WARNING in kcov_remote_start
2025/10/10 10:09 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in kcov_remote_start
2025/07/13 12:19 linux-6.1.y dfc486ec9cce 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in kcov_remote_start
2025/06/28 15:33 linux-6.1.y 7e69c33e4858 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 WARNING in kcov_remote_start
* Struck through repros no longer work on HEAD.