general protection fault in ucsi_acpi_probe

Status: upstream: reported C repro on 2026/09/14 23:32
Reported-by: syzbot+acec6adf59953637218f@syzkaller.appspotmail.com
First crash: 8h37m, last: 4h46m
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 general protection fault in ucsi_acpi_probe 2 4 6h59m 28d 0/2 upstream: reported on 2026/08/17 09:45
upstream general protection fault in ucsi_acpi_probe usb prio:low 2 syz 17 11d 24d 0/29 closed as invalid on 2026/09/07 09:32
upstream general protection fault in ucsi_acpi_probe (2) usb prio:low 2 syz, C error 20 5h36m 10h43m 0/29 upstream: reported C repro on 2026/09/14 21:26
linux-6.1 general protection fault in ucsi_acpi_probe 2 2 7h55m 7h54m 0/3 upstream: reported on 2026/09/15 00:15

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc00000000f8: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000007c0-0x00000000000007c7]
CPU: 0 PID: 4344 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:ucsi_acpi_probe+0x68/0x550 drivers/usb/typec/ucsi/ucsi_acpi.c:131
Code: 89 74 24 08 4c 8b 23 4c 89 e7 e8 c3 ae d4 fd 49 83 c4 f0 45 31 f6 84 c0 4d 0f 45 f4 49 81 c6 c4 07 00 00 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 95 04 00 00 41 8b 2e 31 ff 89 ee e8 bf
RSP: 0018:ffffc90002fffa60 EFLAGS: 00010203
RAX: 00000000000000f8 RBX: ffff888017b054a8 RCX: ffff88801e4d5940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88802298b48b R09: 1ffff11004531691
R10: dffffc0000000000 R11: ffffed1004531692 R12: fffffffffffffff0
R13: dffffc0000000000 R14: 00000000000007c4 R15: 1ffff11002f60a95
FS:  000055556eb6a500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30963fff CR3: 0000000073fb2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 platform_probe+0x137/0x1c0 drivers/base/platform.c:1391
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x276/0xc70 drivers/base/dd.c:595
 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:775
 device_driver_attach+0xdc/0x1d0 drivers/base/dd.c:1096
 bind_store+0x33b/0x380 drivers/base/bus.c:216
 kernfs_fop_write_iter+0x3a8/0x500 fs/kernfs/file.c:296
 call_write_iter include/linux/fs.h:2179 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x748/0xd70 fs/read_write.c:594
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fea7fd05159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffda74ec308 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fea7ff8cfa0 RCX: 00007fea7fd05159
RDX: 0000000000000007 RSI: 0000200000000600 RDI: 0000000000000006
RBP: 00007fea7fd9c03b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fea7ff8cfac R14: 00007fea7ff8cfa0 R15: 00007fea7ff8cfa0
 </TASK>
Modules linked in:
---[ end trace b94482bdcc316d73 ]---
RIP: 0010:ucsi_acpi_probe+0x68/0x550 drivers/usb/typec/ucsi/ucsi_acpi.c:131
Code: 89 74 24 08 4c 8b 23 4c 89 e7 e8 c3 ae d4 fd 49 83 c4 f0 45 31 f6 84 c0 4d 0f 45 f4 49 81 c6 c4 07 00 00 4c 89 f0 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 95 04 00 00 41 8b 2e 31 ff 89 ee e8 bf
RSP: 0018:ffffc90002fffa60 EFLAGS: 00010203
RAX: 00000000000000f8 RBX: ffff888017b054a8 RCX: ffff88801e4d5940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88802298b48b R09: 1ffff11004531691
R10: dffffc0000000000 R11: ffffed1004531692 R12: fffffffffffffff0
R13: dffffc0000000000 R14: 00000000000007c4 R15: 1ffff11002f60a95
FS:  000055556eb6a500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056311f6c1400 CR3: 0000000073fb2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	89 74 24 08          	mov    %esi,0x8(%rsp)
   4:	4c 8b 23             	mov    (%rbx),%r12
   7:	4c 89 e7             	mov    %r12,%rdi
   a:	e8 c3 ae d4 fd       	call   0xfdd4aed2
   f:	49 83 c4 f0          	add    $0xfffffffffffffff0,%r12
  13:	45 31 f6             	xor    %r14d,%r14d
  16:	84 c0                	test   %al,%al
  18:	4d 0f 45 f4          	cmovne %r12,%r14
  1c:	49 81 c6 c4 07 00 00 	add    $0x7c4,%r14
  23:	4c 89 f0             	mov    %r14,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 95 04 00 00    	jne    0x4cc
  37:	41 8b 2e             	mov    (%r14),%ebp
  3a:	31 ff                	xor    %edi,%edi
  3c:	89 ee                	mov    %ebp,%esi
  3e:	e8                   	.byte 0xe8
  3f:	bf                   	.byte 0xbf

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/15 03:23 linux-5.15.y 0248c33e835e 81a27d1a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan general protection fault in ucsi_acpi_probe
2026/09/14 23:32 linux-5.15.y 0248c33e835e 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan general protection fault in ucsi_acpi_probe
2026/09/14 23:32 linux-5.15.y 0248c33e835e 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan general protection fault in ucsi_acpi_probe
* Struck through repros no longer work on HEAD.