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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: 14077 Comm: syz.6.5840 Not tainted 6.1.129-syzkaller-00054-g3e6e324f5b47 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:dev_map_generic_redirect+0x90/0x7d0 kernel/bpf/devmap.c:668
Code: f1 f1 00 f2 f2 f2 4b 89 04 26 43 c7 44 26 0f f3 f3 f3 f3 43 c6 44 26 13 f3 e8 8c db dd ff 48 89 d8 48 c1 e8 03 48 89 44 24 48 <42> 80 3c 20 00 74 08 48 89 df e8 81 88 25 00 48 89 5c 24 18 4c 8b
RSP: 0018:ffffc90002c4f6a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9000167a000 RSI: 0000000000000475 RDI: 0000000000000476
RBP: ffffc90002c4f7f0 R08: ffffffff8415998d R09: ffffffff841598ab
R10: 0000000000000004 R11: ffff88812c7b0000 R12: dffffc0000000000
R13: ffff88812230b280 R14: 1ffff92000589ee0 R15: dffffc0000000000
FS:  00007fed2edff6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000f000 CR3: 0000000125b70000 CR4: 00000000003526a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 xdp_do_generic_redirect_map net/core/filter.c:4415 [inline]
 xdp_do_generic_redirect+0x42e/0xb40 net/core/filter.c:4474
 do_xdp_generic+0x53e/0x800 net/core/dev.c:4968
 tun_get_user+0x238a/0x3a90 drivers/net/tun.c:1920
 tun_chr_write_iter+0x129/0x210 drivers/net/tun.c:2044
 call_write_iter include/linux/fs.h:2274 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0xaf6/0xed0 fs/read_write.c:584
 ksys_write+0x199/0x2c0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:646
 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fed2ef8bc1f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007fed2edff000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fed2f1a5fa0 RCX: 00007fed2ef8bc1f
RDX: 000000000000fdef RSI: 0000200000000180 RDI: 00000000000000c8
RBP: 00007fed2f00e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000fdef R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fed2f1a5fa0 R15: 00007ffc8635cba8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dev_map_generic_redirect+0x90/0x7d0 kernel/bpf/devmap.c:668
Code: f1 f1 00 f2 f2 f2 4b 89 04 26 43 c7 44 26 0f f3 f3 f3 f3 43 c6 44 26 13 f3 e8 8c db dd ff 48 89 d8 48 c1 e8 03 48 89 44 24 48 <42> 80 3c 20 00 74 08 48 89 df e8 81 88 25 00 48 89 5c 24 18 4c 8b
RSP: 0018:ffffc90002c4f6a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9000167a000 RSI: 0000000000000475 RDI: 0000000000000476
RBP: ffffc90002c4f7f0 R08: ffffffff8415998d R09: ffffffff841598ab
R10: 0000000000000004 R11: ffff88812c7b0000 R12: dffffc0000000000
R13: ffff88812230b280 R14: 1ffff92000589ee0 R15: dffffc0000000000
FS:  00007fed2edff6c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000000f000 CR3: 0000000125b70000 CR4: 00000000003526a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	f1                   	int1
   1:	f1                   	int1
   2:	00 f2                	add    %dh,%dl
   4:	f2 f2 4b 89 04 26    	repnz repnz mov %rax,(%r14,%r12,1)
   a:	43 c7 44 26 0f f3 f3 	movl   $0xf3f3f3f3,0xf(%r14,%r12,1)
  11:	f3 f3
  13:	43 c6 44 26 13 f3    	movb   $0xf3,0x13(%r14,%r12,1)
  19:	e8 8c db dd ff       	call   0xffdddbaa
  1e:	48 89 d8             	mov    %rbx,%rax
  21:	48 c1 e8 03          	shr    $0x3,%rax
  25:	48 89 44 24 48       	mov    %rax,0x48(%rsp)
* 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 df             	mov    %rbx,%rdi
  34:	e8 81 88 25 00       	call   0x2588ba
  39:	48 89 5c 24 18       	mov    %rbx,0x18(%rsp)
  3e:	4c                   	rex.WR
  3f:	8b                   	.byte 0x8b