[syzbot] [media?] general protection fault in vidtv_psi_desc_assign

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c875a6c32467 Merge tag 'usb-6.19-rc3' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10e63bb4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=8bfa57a8c0ab3aa8
dashboard link: https://syzkaller.appspot.com/bug?extid=1f5bcc7c919ec578777a
compiler: gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8899a01b839d/disk-c875a6c3.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/24b995d869e5/vmlinux-c875a6c3.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a87050fc4ee8/bzImage-c875a6c3.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1f5bcc...@syzkaller.appspotmail.com

RBP: 00007fbc65813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbc659e6038 R14: 00007fbc659e5fa0 R15: 00007ffcd46bbaa8
</TASK>
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 17992 Comm: syz.1.2581 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:vidtv_psi_desc_assign+0x24/0x90 drivers/media/test-drivers/vidtv/vidtv_psi.c:629
Code: 90 90 90 90 90 90 0f 1f 40 d6 41 54 55 48 89 f5 53 48 89 fb e8 dd 65 b9 f9 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 75 47 4c 8b 23 49 39 ec 74 36 e8 b9 65 b9 f9 4d 85 e4
RSP: 0018:ffffc9000c61fa20 EFLAGS: 00010247
RAX: dffffc0000000000 RBX: 0000000000000005 RCX: ffffc9000daab000
RDX: 0000000000000000 RSI: ffffffff8804f313 RDI: 0000000000000005
RBP: ffff88807da44660 R08: 0000000000000000 R09: 4453534204050000
R10: 0000000000000005 R11: ffff88802cc229b0 R12: 0000000000000000
R13: ffff88807b485640 R14: ffff88801feace80 R15: ffff8880338e7800
FS: 00007fbc665bb6c0(0000) GS:ffff8881248fc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200001000000 CR3: 00000000767b2000 CR4: 00000000003526f0
Call Trace:
<TASK>
vidtv_channel_pmt_match_sections drivers/media/test-drivers/vidtv/vidtv_channel.c:349 [inline]
vidtv_channel_si_init+0x1445/0x1a50 drivers/media/test-drivers/vidtv/vidtv_channel.c:479
vidtv_mux_init+0x526/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:519
vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 [inline]
vidtv_start_feed+0x33e/0x4d0 drivers/media/test-drivers/vidtv/vidtv_bridge.c:239
dmx_ts_feed_start_filtering+0xf6/0x220 drivers/media/dvb-core/dvb_demux.c:747
dvb_dmxdev_start_feed+0x273/0x3f0 drivers/media/dvb-core/dmxdev.c:655
dvb_dmxdev_filter_start+0x1b6/0xe10 drivers/media/dvb-core/dmxdev.c:766
dvb_dmxdev_pes_filter_set drivers/media/dvb-core/dmxdev.c:963 [inline]
dvb_demux_do_ioctl+0x9de/0x12f0 drivers/media/dvb-core/dmxdev.c:1077
dvb_usercopy+0x167/0x340 drivers/media/dvb-core/dvbdev.c:999
dvb_demux_ioctl+0x29/0x40 drivers/media/dvb-core/dmxdev.c:1186
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbc6578f7c9
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:00007fbc665bb038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fbc659e5fa0 RCX: 00007fbc6578f7c9
RDX: 0000000000000000 RSI: 0000000040146f2c RDI: 0000000000000003
RBP: 00007fbc65813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbc659e6038 R14: 00007fbc659e5fa0 R15: 00007ffcd46bbaa8
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:vidtv_psi_desc_assign+0x24/0x90 drivers/media/test-drivers/vidtv/vidtv_psi.c:629
Code: 90 90 90 90 90 90 0f 1f 40 d6 41 54 55 48 89 f5 53 48 89 fb e8 dd 65 b9 f9 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 75 47 4c 8b 23 49 39 ec 74 36 e8 b9 65 b9 f9 4d 85 e4
RSP: 0018:ffffc9000c61fa20 EFLAGS: 00010247
RAX: dffffc0000000000 RBX: 0000000000000005 RCX: ffffc9000daab000
RDX: 0000000000000000 RSI: ffffffff8804f313 RDI: 0000000000000005
RBP: ffff88807da44660 R08: 0000000000000000 R09: 4453534204050000
R10: 0000000000000005 R11: ffff88802cc229b0 R12: 0000000000000000
R13: ffff88807b485640 R14: ffff88801feace80 R15: ffff8880338e7800
FS: 00007fbc665bb6c0(0000) GS:ffff8881248fc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557f4c7cc950 CR3: 00000000767b2000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
0: 90 nop
1: 90 nop
2: 90 nop
3: 90 nop
4: 90 nop
5: 90 nop
6: 0f 1f 40 d6 nopl -0x2a(%rax)
a: 41 54 push %r12
c: 55 push %rbp
d: 48 89 f5 mov %rsi,%rbp
10: 53 push %rbx
11: 48 89 fb mov %rdi,%rbx
14: e8 dd 65 b9 f9 call 0xf9b965f6
19: 48 89 da mov %rbx,%rdx
1c: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
23: fc ff df
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
2e: 75 47 jne 0x77
30: 4c 8b 23 mov (%rbx),%r12
33: 49 39 ec cmp %rbp,%r12
36: 74 36 je 0x6e
38: e8 b9 65 b9 f9 call 0xf9b965f6
3d: 4d 85 e4 test %r12,%r12


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