syzbot
general protection fault in dummy_set_selfpowered
Status:
upstream: reported on 2026/07/24 22:03
Reported-by: syzbot+9e82e63d823b71764eb6@syzkaller.appspotmail.com
First crash: 10d, last: 6d06h
Sample crash report:
Mass Storage Function, version: 2009/09/11
LUN: removable file: (no medium)
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 PID: 8112 Comm: syz.2.1025 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:dummy_set_selfpowered+0xb7/0x150 drivers/usb/gadget/udc/dummy_hcd.c:884
Code: 94 c0 4d 8d b4 c6 f8 06 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 13 b4 87 fb 4d 8b 3e 4c 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ff e8 fa b3 87 fb 41 be f0 12 00 00 4d
RSP: 0018:ffffc9000166fa38 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88802604d940
RDX: 0000000000000002 RSI: 0000000000000003 RDI: 0000000000000005
RBP: 0000000000000003 R08: ffffffff8c44fd07 R09: 1ffffffff1889fa0
R10: dffffc0000000000 R11: fffffbfff1889fa1 R12: dffffc0000000000
R13: ffff888074c974b8 R14: ffff8880205652f8 R15: 0000000000000000
FS: 00007f5206b8d6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32a14ff8 CR3: 00000000770b0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
usb_gadget_set_selfpowered+0x6a/0x230 drivers/usb/gadget/udc/core.c:561
composite_dev_prepare+0x2f3/0x310 drivers/usb/gadget/composite.c:2323
configfs_composite_bind+0xa1/0xf60 drivers/usb/gadget/configfs.c:1310
udc_bind_to_driver+0x203/0x5f0 drivers/usb/gadget/udc/core.c:1574
usb_gadget_probe_driver+0x1fb/0x380 drivers/usb/gadget/udc/core.c:1637
gadget_dev_desc_UDC_store+0x1ba/0x2e0 drivers/usb/gadget/configfs.c:289
flush_write_buffer fs/configfs/file.c:207 [inline]
configfs_write_iter+0x30b/0x400 fs/configfs/file.c:229
call_write_iter include/linux/fs.h:2173 [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: 0033:0x7f5208934e99
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:00007f5206b8d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f5208bbcfa0 RCX: 00007f5208934e99
RDX: 000000000000000b RSI: 0000200000000d00 RDI: 0000000000000004
RBP: 00007f52089caeaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5208bbd038 R14: 00007f5208bbcfa0 R15: 00007ffd880e4768
</TASK>
Modules linked in:
---[ end trace 62b1b3055cc2c697 ]---
RIP: 0010:dummy_set_selfpowered+0xb7/0x150 drivers/usb/gadget/udc/dummy_hcd.c:884
Code: 94 c0 4d 8d b4 c6 f8 06 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 13 b4 87 fb 4d 8b 3e 4c 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 08 4c 89 ff e8 fa b3 87 fb 41 be f0 12 00 00 4d
RSP: 0018:ffffc9000166fa38 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88802604d940
RDX: 0000000000000002 RSI: 0000000000000003 RDI: 0000000000000005
RBP: 0000000000000003 R08: ffffffff8c44fd07 R09: 1ffffffff1889fa0
R10: dffffc0000000000 R11: fffffbfff1889fa1 R12: dffffc0000000000
R13: ffff888074c974b8 R14: ffff8880205652f8 R15: 0000000000000000
FS: 00007f5206b8d6c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32224000 CR3: 00000000770b0000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 94 xchg %eax,%esp
1: c0 4d 8d b4 rorb $0xb4,-0x73(%rbp)
5: c6 f8 06 xabort $0x6
8: 00 00 add %al,(%rax)
a: 4c 89 f0 mov %r14,%rax
d: 48 c1 e8 03 shr $0x3,%rax
11: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1)
16: 74 08 je 0x20
18: 4c 89 f7 mov %r14,%rdi
1b: e8 13 b4 87 fb call 0xfb87b433
20: 4d 8b 3e mov (%r14),%r15
23: 4c 89 f8 mov %r15,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 4c 89 ff mov %r15,%rdi
34: e8 fa b3 87 fb call 0xfb87b433
39: 41 be f0 12 00 00 mov $0x12f0,%r14d
3f: 4d rex.WRB
* Struck through repros no longer work on HEAD.