Re: [syzbot] [wireless?] general protection fault in cfg80211_mlme_deauth

[syzbot <syzbot+00778a9a557a2a5e1a33@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
general protection fault in cfg80211_mlme_deauth

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 790 Comm: kworker/0:2 Not tainted 6.15.0-rc1-syzkaller-g0af2f6be1b42-dirty #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events cfg80211_conn_work
RIP: 0010:ether_addr_equal include/linux/etherdevice.h:355 [inline]
RIP: 0010:cfg80211_mlme_deauth+0x35a/0x940 net/wireless/mlme.c:514
Code: 8d 9c 24 b0 00 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 4c 8b 7c 24 28 0f 85 25 03 00 00 44 8b 23 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 2b 03 00 00 45 8b 37 48 8b 44 24 20 48
RSP: 0018:ffffc90001acf160 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880437a4e40 RCX: ffff888000784880
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90001acf248 R08: ffffffff8b8395d8 R09: 0000000000000003
R10: 0000000000000009 R11: ffff888000784880 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000003 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88808c596000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001080 CR3: 0000000011f84000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 cfg80211_conn_do_work+0x369/0xed0 net/wireless/sme.c:229
 cfg80211_conn_work+0x35e/0x5b0 net/wireless/sme.c:279
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd50 kernel/workqueue.c:3400
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ether_addr_equal include/linux/etherdevice.h:355 [inline]
RIP: 0010:cfg80211_mlme_deauth+0x35a/0x940 net/wireless/mlme.c:514
Code: 8d 9c 24 b0 00 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 4c 8b 7c 24 28 0f 85 25 03 00 00 44 8b 23 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 2b 03 00 00 45 8b 37 48 8b 44 24 20 48
RSP: 0018:ffffc90001acf160 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880437a4e40 RCX: ffff888000784880
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90001acf248 R08: ffffffff8b8395d8 R09: 0000000000000003
R10: 0000000000000009 R11: ffff888000784880 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000003 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88808c596000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001080 CR3: 00000000124d8000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	8d 9c 24 b0 00 00 00 	lea    0xb0(%rsp),%ebx
   7:	48 89 d8             	mov    %rbx,%rax
   a:	48 c1 e8 03          	shr    $0x3,%rax
   e:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax
  13:	84 c0                	test   %al,%al
  15:	4c 8b 7c 24 28       	mov    0x28(%rsp),%r15
  1a:	0f 85 25 03 00 00    	jne    0x345
  20:	44 8b 23             	mov    (%rbx),%r12d
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 2b 03 00 00    	jne    0x362
  37:	45 8b 37             	mov    (%r15),%r14d
  3a:	48 8b 44 24 20       	mov    0x20(%rsp),%rax
  3f:	48                   	rex.W


Tested on:

commit:         0af2f6be Linux 6.15-rc1
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10c8b74c580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=66996a2350ef05e0
dashboard link: https://syzkaller.appspot.com/bug?extid=00778a9a557a2a5e1a33
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=15217b4c580000