Subject: [syzbot] [wpan?] general protection fault in nl802154_trigger_scan

From: syzbot <[email-masked]>
Date: Fri, 03 Mar 2023 06:30:49 -0800

Hello,

syzbot found the following issue on:

HEAD commit:    f3a2439f20d9 Merge tag 'rproc-v6.3' of git://git.kernel.or..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=12df1a7f480000
kernel config:  https://syzkaller.appspot.com/x/.config?x=81f5afa0c201c8de
dashboard link: https://syzkaller.appspot.com/bug?extid=bd85b31816913a32e473
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1597f254c80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15053e40c80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0719d575f3ac/disk-f3a2439f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4176aabb67b5/vmlinux-f3a2439f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2b0e3c0ab205/bzImage-f3a2439f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 5076 Comm: syz-executor386 Not tainted 6.2.0-syzkaller-12485-gf3a2439f20d9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023
RIP: 0010:nla_get_u8 include/net/netlink.h:1658 [inline]
RIP: 0010:nl802154_trigger_scan+0x132/0xc90 net/ieee802154/nl802154.c:1415
Code: 48 c1 ea 03 80 3c 02 00 0f 85 3f 0a 00 00 48 8b ad f8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7d 04 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 d0 07 00 00
RSP: 0018:ffffc90003397568 EFLAGS: 00010247
RAX: dffffc0000000000 RBX: ffffc900033975d8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff89cec1a1 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888146fb4c90
R13: ffff888146f82000 R14: ffff888146f820a0 R15: ffffc900033975f8
FS:  0000555556c9b300(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055be8d9c04f0 CR3: 0000000023513000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 genl_family_rcv_msg_doit.isra.0+0x1e6/0x2d0 net/netlink/genetlink.c:968
 genl_family_rcv_msg net/netlink/genetlink.c:1048 [inline]
 genl_rcv_msg+0x4ff/0x7e0 net/netlink/genetlink.c:1065
 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2574
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1076
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1942
 sock_sendmsg_nosec net/socket.c:722 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:745
 ____sys_sendmsg+0x71c/0x900 net/socket.c:2504
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2558
 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2587
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f416cc9ee69
Code: 28 c3 e8 5a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff243fe498 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f416cd17380 RCX: 00007f416cc9ee69
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 0000000000000001 R08: 0000000000000000 R09: 001d00000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 0000000000000003 R14: 00007fff243fe4b7 R15: 00007fff243fe4ba
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:nla_get_u8 include/net/netlink.h:1658 [inline]
RIP: 0010:nl802154_trigger_scan+0x132/0xc90 net/ieee802154/nl802154.c:1415
Code: 48 c1 ea 03 80 3c 02 00 0f 85 3f 0a 00 00 48 8b ad f8 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7d 04 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 d0 07 00 00
RSP: 0018:ffffc90003397568 EFLAGS: 00010247
RAX: dffffc0000000000 RBX: ffffc900033975d8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff89cec1a1 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888146fb4c90
R13: ffff888146f82000 R14: ffff888146f820a0 R15: ffffc900033975f8
FS:  0000555556c9b300(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055be8d9c04f0 CR3: 0000000023513000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	48 c1 ea 03          	shr    $0x3,%rdx
   4:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   8:	0f 85 3f 0a 00 00    	jne    0xa4d
   e:	48 8b ad f8 00 00 00 	mov    0xf8(%rbp),%rbp
  15:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1c:	fc ff df
  1f:	48 8d 7d 04          	lea    0x4(%rbp),%rdi
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax <-- trapping instruction
  2e:	48 89 fa             	mov    %rdi,%rdx
  31:	83 e2 07             	and    $0x7,%edx
  34:	38 d0                	cmp    %dl,%al
  36:	7f 08                	jg     0x40
  38:	84 c0                	test   %al,%al
  3a:	0f 85 d0 07 00 00    	jne    0x810

---
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