general protection fault, probably for non-canonical address 0xdffffc0000000121: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000908-0x000000000000090f] CPU: 0 PID: 10720 Comm: syz.0.1408 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:dvb_device_open+0xde/0x370 drivers/media/dvb-core/dvbdev.c:103 Code: 4c 89 e5 48 c1 ed 03 80 7c 1d 00 00 74 08 4c 89 e7 e8 56 c1 dc fa 4d 8b 2c 24 4d 85 ed 0f 84 5e 01 00 00 4c 89 e8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ef e8 34 c1 dc fa 49 8b 7d 00 e8 8b 80 71 RSP: 0018:ffffc900037f77f0 EFLAGS: 00010206 RAX: 0000000000000121 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000008 RDI: 00000000ffffffff RBP: 1ffff110282cc8c3 R08: ffffffff8df00e0f R09: 1ffffffff1be01c1 R10: dffffc0000000000 R11: fffffbfff1be01c2 R12: ffff888141664618 R13: 000000000000090a R14: ffff8880263fb0b0 R15: ffff888141664600 FS: 00007f9a58a1c6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f83e6185fc0 CR3: 000000005d386000 CR4: 00000000003506f0 Call Trace: chrdev_open+0x5cc/0x6a0 fs/char_dev.c:414 do_dentry_open+0x8c6/0x1500 fs/open.c:929 do_open fs/namei.c:3640 [inline] path_openat+0x27f1/0x3230 fs/namei.c:3797 do_filp_open+0x1f5/0x430 fs/namei.c:3824 do_sys_openat2+0x134/0x1d0 fs/open.c:1421 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1447 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f9a57b5d68e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007f9a58a1bb28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f9a58a1c6c0 RCX: 00007f9a57b5d68e RDX: 0000000000000002 RSI: 00007f9a58a1bc00 RDI: ffffffffffffff9c RBP: 00007f9a58a1bc00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd R13: 00007f9a57e16128 R14: 00007f9a57e16090 R15: 00007ffcd7d34728 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:dvb_device_open+0xde/0x370 drivers/media/dvb-core/dvbdev.c:103 Code: 4c 89 e5 48 c1 ed 03 80 7c 1d 00 00 74 08 4c 89 e7 e8 56 c1 dc fa 4d 8b 2c 24 4d 85 ed 0f 84 5e 01 00 00 4c 89 e8 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 ef e8 34 c1 dc fa 49 8b 7d 00 e8 8b 80 71 RSP: 0018:ffffc900037f77f0 EFLAGS: 00010206 RAX: 0000000000000121 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000008 RDI: 00000000ffffffff RBP: 1ffff110282cc8c3 R08: ffffffff8df00e0f R09: 1ffffffff1be01c1 R10: dffffc0000000000 R11: fffffbfff1be01c2 R12: ffff888141664618 R13: 000000000000090a R14: ffff8880263fb0b0 R15: ffff888141664600 FS: 00007f9a58a1c6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f83e6185fc0 CR3: 000000005d386000 CR4: 00000000003506f0 ---------------- Code disassembly (best guess): 0: 4c 89 e5 mov %r12,%rbp 3: 48 c1 ed 03 shr $0x3,%rbp 7: 80 7c 1d 00 00 cmpb $0x0,0x0(%rbp,%rbx,1) c: 74 08 je 0x16 e: 4c 89 e7 mov %r12,%rdi 11: e8 56 c1 dc fa call 0xfadcc16c 16: 4d 8b 2c 24 mov (%r12),%r13 1a: 4d 85 ed test %r13,%r13 1d: 0f 84 5e 01 00 00 je 0x181 23: 4c 89 e8 mov %r13,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 4c 89 ef mov %r13,%rdi 33: e8 34 c1 dc fa call 0xfadcc16c 38: 49 8b 7d 00 mov 0x0(%r13),%rdi 3c: e8 .byte 0xe8 3d: 8b .byte 0x8b 3e: 80 .byte 0x80 3f: 71 .byte 0x71