syzbot

Oops: general protection fault, probably for non-canonical address 0xdffffc000000000a: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000050-0x0000000000000057]
CPU: 1 UID: 0 PID: 5499 Comm: syz.4.38 Not tainted 6.11.0-rc5-next-20240827-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:pick_next_entity kernel/sched/fair.c:5613 [inline]
RIP: 0010:pick_task_fair+0xc3/0x280 kernel/sched/fair.c:8742
Code: 00 00 80 3b 00 74 08 4c 89 ef e8 58 7d 01 00 0f 1f 44 00 00 4c 89 ef e8 6b f8 01 00 49 89 c4 48 8d 58 51 48 89 d8 48 c1 e8 03 <0f> b6 04 28 84 c0 75 5e 80 3b 00 74 2e 48 8b 3c 24 4c 89 e6 ba 01
RSP: 0018:ffffc90004e8f1a8 EFLAGS: 00010006
RAX: 000000000000000a RBX: 0000000000000051 RCX: dffffc0000000000
RDX: dffffc0000000000 RSI: 00000000000001aa RDI: ffff88807d547058
RBP: dffffc0000000000 R08: ffffffff818ca2f8 R09: 1ffffffff20386c5
R10: dffffc0000000000 R11: ffffffff81668340 R12: 0000000000000000
R13: ffff88807d547000 R14: ffff8880b913eb90 R15: 1ffff11017227d72
FS:  00007fcc398966c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3280fff8 CR3: 00000000578fe000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 pick_task_dl+0xd3/0x200 kernel/sched/deadline.c:2446
 pick_task kernel/sched/core.c:6028 [inline]
 pick_next_task kernel/sched/core.c:6130 [inline]
 __schedule+0x2eab/0x4b30 kernel/sched/core.c:6632
 __schedule_loop kernel/sched/core.c:6754 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6769
 schedule_timeout+0xb0/0x310 kernel/time/timer.c:2559
 unix_wait_for_peer+0x250/0x340 net/unix/af_unix.c:1529
 unix_dgram_sendmsg+0x127f/0x1f80 net/unix/af_unix.c:2131
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:745
 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2597
 ___sys_sendmsg net/socket.c:2651 [inline]
 __sys_sendmmsg+0x3ab/0x730 net/socket.c:2737
 __do_sys_sendmmsg net/socket.c:2766 [inline]
 __se_sys_sendmmsg net/socket.c:2763 [inline]
 __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2763
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcc38b79e79
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcc39896038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007fcc38d15f80 RCX: 00007fcc38b79e79
RDX: 0000000000000651 RSI: 0000000020000000 RDI: 0000000000000006
RBP: 00007fcc38be793e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcc38d15f80 R15: 00007ffd7bfd9668
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:pick_next_entity kernel/sched/fair.c:5613 [inline]
RIP: 0010:pick_task_fair+0xc3/0x280 kernel/sched/fair.c:8742
Code: 00 00 80 3b 00 74 08 4c 89 ef e8 58 7d 01 00 0f 1f 44 00 00 4c 89 ef e8 6b f8 01 00 49 89 c4 48 8d 58 51 48 89 d8 48 c1 e8 03 <0f> b6 04 28 84 c0 75 5e 80 3b 00 74 2e 48 8b 3c 24 4c 89 e6 ba 01
RSP: 0018:ffffc90004e8f1a8 EFLAGS: 00010006
RAX: 000000000000000a RBX: 0000000000000051 RCX: dffffc0000000000
RDX: dffffc0000000000 RSI: 00000000000001aa RDI: ffff88807d547058
RBP: dffffc0000000000 R08: ffffffff818ca2f8 R09: 1ffffffff20386c5
R10: dffffc0000000000 R11: ffffffff81668340 R12: 0000000000000000
R13: ffff88807d547000 R14: ffff8880b913eb90 R15: 1ffff11017227d72
FS:  00007fcc398966c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3280fff8 CR3: 00000000578fe000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	80 3b 00             	cmpb   $0x0,(%rbx)
   5:	74 08                	je     0xf
   7:	4c 89 ef             	mov    %r13,%rdi
   a:	e8 58 7d 01 00       	call   0x17d67
   f:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  14:	4c 89 ef             	mov    %r13,%rdi
  17:	e8 6b f8 01 00       	call   0x1f887
  1c:	49 89 c4             	mov    %rax,%r12
  1f:	48 8d 58 51          	lea    0x51(%rax),%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	0f b6 04 28          	movzbl (%rax,%rbp,1),%eax <-- trapping instruction
  2e:	84 c0                	test   %al,%al
  30:	75 5e                	jne    0x90
  32:	80 3b 00             	cmpb   $0x0,(%rbx)
  35:	74 2e                	je     0x65
  37:	48 8b 3c 24          	mov    (%rsp),%rdi
  3b:	4c 89 e6             	mov    %r12,%rsi
  3e:	ba                   	.byte 0xba
  3f:	01                   	.byte 0x1