syzbot
WARNING in drv_unassign_vif_chanctx (4)
Status:
upstream: reported on 2026/08/13 00:09
Subsystems:
wireless
Labels:
prio:low
[Documentation on labels]
Reported-by: syzbot+63a84ea9c0f57d6133fa@syzkaller.appspotmail.com
First crash: 27d, last: 2d01h
Sample crash report:
------------[ cut here ]------------
wlan0: Failed check-sdata-in-driver check, flags: 0x0
WARNING: net/mac80211/driver-ops.c:366 at drv_unassign_vif_chanctx+0x1ef/0x820 net/mac80211/driver-ops.c:366, CPU#0: syz.3.1749/12629
Modules linked in:
CPU: 0 UID: 0 PID: 12629 Comm: syz.3.1749 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:drv_unassign_vif_chanctx+0x1f7/0x820 net/mac80211/driver-ops.c:366
Code: 00 00 e8 3c 44 d0 f6 48 8b 34 24 48 81 c6 20 01 00 00 48 89 34 24 e8 28 44 d0 f6 48 8d 3d 61 84 1a 06 8b 54 24 0c 48 8b 34 24 <67> 48 0f b9 3a eb 07 4c 8d b3 68 0a 00 00 e8 06 44 d0 f6 4c 89 f2
RSP: 0018:ffffc900038bf0e0 EFLAGS: 00010202
RAX: 0000000000000003 RBX: ffff888059230ec0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff888059230120 RDI: ffffffff91563050
RBP: ffff888059270f40 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 000000000000b9ec R12: ffff888059232f88
R13: ffff888059a6a400 R14: ffff888059231928 R15: ffff888059232c70
FS: 00007f82936e96c0(0000) GS:ffff888123b61000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f828c000020 CR3: 0000000075e5b000 CR4: 00000000003526f0
Call Trace:
<TASK>
ieee80211_assign_link_chanctx+0x5ec/0xeb0 net/mac80211/chan.c:1201
__ieee80211_link_release_channel+0x2f8/0x5b0 net/mac80211/chan.c:2178
ieee80211_link_release_channel+0x128/0x200 net/mac80211/chan.c:2494
ieee80211_teardown_sdata+0xc4/0x250 net/mac80211/iface.c:916
ieee80211_if_change_type+0x29f/0x790 net/mac80211/iface.c:2088
ieee80211_change_iface+0xad/0x920 net/mac80211/cfg.c:271
rdev_change_virtual_intf net/wireless/rdev-ops.h:74 [inline]
cfg80211_change_iface+0x569/0xdf0 net/wireless/util.c:1310
nl80211_set_interface+0x875/0xc80 net/wireless/nl80211.c:5108
genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2556
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1900
sock_sendmsg_nosec net/socket.c:800 [inline]
__sock_sendmsg net/socket.c:815 [inline]
____sys_sendmsg+0xa4d/0xbe0 net/socket.c:2713
___sys_sendmsg+0x190/0x1e0 net/socket.c:2767
__sys_sendmsg+0x160/0x210 net/socket.c:2799
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f829279e159
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:00007f82936e9028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f8292a26090 RCX: 00007f829279e159
RDX: 0000000000000000 RSI: 0000200000000100 RDI: 0000000000000007
RBP: 00007f8292835024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8292a26128 R14: 00007f8292a26090 R15: 00007fffb5a0f5b8
</TASK>
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: e8 3c 44 d0 f6 call 0xf6d04443
7: 48 8b 34 24 mov (%rsp),%rsi
b: 48 81 c6 20 01 00 00 add $0x120,%rsi
12: 48 89 34 24 mov %rsi,(%rsp)
16: e8 28 44 d0 f6 call 0xf6d04443
1b: 48 8d 3d 61 84 1a 06 lea 0x61a8461(%rip),%rdi # 0x61a8483
22: 8b 54 24 0c mov 0xc(%rsp),%edx
26: 48 8b 34 24 mov (%rsp),%rsi
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: eb 07 jmp 0x38
31: 4c 8d b3 68 0a 00 00 lea 0xa68(%rbx),%r14
38: e8 06 44 d0 f6 call 0xf6d04443
3d: 4c 89 f2 mov %r14,%rdx
* Struck through repros no longer work on HEAD.