[syzbot] [kernel?] general protection fault in netdev_register_kobject

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    2ee82481c392 Add linux-next specific files for 20230828
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=16ea87b7a80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e82a7781f9208c0d
dashboard link: https://syzkaller.appspot.com/bug?extid=d2c31705e468a347e6db
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=141c0267a80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1585c0c0680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/30801702ce78/disk-2ee82481.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8d9b67709145/vmlinux-2ee82481.xz
kernel image: https://storage.googleapis.com/syzbot-assets/47f8ef9bffd0/bzImage-2ee82481.xz

The issue was bisected to:

commit d21fdd07cea418c0d98c8a15fc95b8b8970801e7
Author: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Date:   Thu Aug 17 09:12:21 2023 +0000

    driver core: Return proper error code when dev_set_name() fails

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=16cefca8680000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=15cefca8680000
console output: https://syzkaller.appspot.com/x/log.txt?x=11cefca8680000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d2c31705e468a347e6db@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: d21fdd07cea4 ("driver core: Return proper error code when dev_set_name() fails")

RBP: 0000000000000002 R08: 00007ffd497ebaf6 R09: 0000000100000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000f4240 R14: 00000000000162a9 R15: 00007ffd497ebd74
 </TASK>
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 5057 Comm: syz-executor401 Not tainted 6.5.0-next-20230828-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:strchr+0x1b/0xb0 lib/string.c:329
Code: a3 ac f7 48 8b 74 24 08 48 8b 14 24 eb 89 90 f3 0f 1e fa 48 b8 00 00 00 00 00 fc ff df 48 89 fa 55 48 c1 ea 03 53 48 83 ec 10 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 04 84 c0 75 51 0f b6 07 89
RSP: 0018:ffffc90003abf058 EFLAGS: 00010282
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000025 RDI: 0000000000000000
RBP: ffffc90003abf0e8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90003abf0e8
R13: 0000000000000cc0 R14: ffff8880142f8880 R15: 0000000000000001
FS:  0000555555e44380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8bf2d75fc4 CR3: 000000007211d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kvasprintf_const+0x25/0x190 lib/kasprintf.c:45
 kobject_set_name_vargs+0x5a/0x130 lib/kobject.c:272
 kobject_add_varg lib/kobject.c:366 [inline]
 kobject_add+0x12a/0x240 lib/kobject.c:424
 device_add+0x290/0x1ac0 drivers/base/core.c:3560
 netdev_register_kobject+0x183/0x3f0 net/core/net-sysfs.c:2044
 register_netdevice+0xbcb/0x1490 net/core/dev.c:10133
 macvlan_common_newlink+0x1102/0x1a40 drivers/net/macvlan.c:1545
 rtnl_newlink_create net/core/rtnetlink.c:3485 [inline]
 __rtnl_newlink+0x1177/0x1940 net/core/rtnetlink.c:3705
 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3718
 rtnetlink_rcv_msg+0x439/0xd30 net/core/rtnetlink.c:6444
 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2545
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0x536/0x810 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x93c/0xe40 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg+0xd9/0x180 net/socket.c:753
 ____sys_sendmsg+0x6ac/0x940 net/socket.c:2540
 ___sys_sendmsg+0x135/0x1d0 net/socket.c:2594
 __sys_sendmsg+0x117/0x1e0 net/socket.c:2623
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f8bf2d14ce9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 d1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd497ebd58 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f8bf2d14ce9
RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000003
RBP: 0000000000000002 R08: 00007ffd497ebaf6 R09: 0000000100000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000f4240 R14: 00000000000162a9 R15: 00007ffd497ebd74
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:strchr+0x1b/0xb0 lib/string.c:329
Code: a3 ac f7 48 8b 74 24 08 48 8b 14 24 eb 89 90 f3 0f 1e fa 48 b8 00 00 00 00 00 fc ff df 48 89 fa 55 48 c1 ea 03 53 48 83 ec 10 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 04 84 c0 75 51 0f b6 07 89
RSP: 0018:ffffc90003abf058 EFLAGS: 00010282
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000025 RDI: 0000000000000000
RBP: ffffc90003abf0e8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90003abf0e8
R13: 0000000000000cc0 R14: ffff8880142f8880 R15: 0000000000000001
FS:  0000555555e44380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005628e3c36050 CR3: 000000007211d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	a3 ac f7 48 8b 74 24 	movabs %eax,0x480824748b48f7ac
   7:	08 48
   9:	8b 14 24             	mov    (%rsp),%edx
   c:	eb 89                	jmp    0xffffff97
   e:	90                   	nop
   f:	f3 0f 1e fa          	endbr64
  13:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1a:	fc ff df
  1d:	48 89 fa             	mov    %rdi,%rdx
  20:	55                   	push   %rbp
  21:	48 c1 ea 03          	shr    $0x3,%rdx
  25:	53                   	push   %rbx
  26:	48 83 ec 10          	sub    $0x10,%rsp
* 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 04                	jg     0x3c
  38:	84 c0                	test   %al,%al
  3a:	75 51                	jne    0x8d
  3c:	0f b6 07             	movzbl (%rdi),%eax
  3f:	89                   	.byte 0x89


---
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