syzbot


BUG: unable to handle kernel NULL pointer dereference in format_decode

Status: closed as invalid on 2020/06/17 13:13
Subsystems: usb
[Documentation on labels]
First crash: 1407d, last: 1407d

Sample crash report:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 69aba067 P4D 69aba067 PUD 6394d067 PMD 0 
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 11745 Comm: syz-executor.3 Not tainted 5.7.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x43/0x60 kernel/kcov.c:202
Code: 24 74 0f 80 e6 01 74 35 8b 90 04 14 00 00 85 d2 74 2b 8b 90 e0 13 00 00 83 fa 02 75 20 48 8b 88 e8 13 00 00 8b 80 e4 13 00 00 <48> 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 66 0f
RSP: 0018:ffffc90000db7960 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff88b2a4c0 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff83b1d0ab RDI: 0000000000000001
RBP: ffffc90000db7a80 R08: ffff888065ac96c0 R09: ffffed1004eb0c2f
R10: ffff888027586174 R11: ffffed1004eb0c2e R12: dffffc0000000000
R13: ffffffff88b2a4c0 R14: 1ffff920001b6f30 R15: 0000000000000055
FS:  0000000000000000(0000) GS:ffff88802cf00000(0063) knlGS:00000000f5d7ab40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000644a8000 CR4: 0000000000340ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 format_decode+0x14b/0xad0 lib/vsprintf.c:2355
 vsnprintf+0x155/0x14f0 lib/vsprintf.c:2572
 add_uevent_var+0x14d/0x310 lib/kobject_uevent.c:664
 usb_udc_uevent+0x6c/0x130 drivers/usb/gadget/udc/core.c:1585
 dev_uevent+0x26a/0x540 drivers/base/core.c:1501
 kobject_uevent_env+0x4c9/0x12e0 lib/kobject_uevent.c:556
 udc_bind_to_driver+0x317/0x570 drivers/usb/gadget/udc/core.c:1368
 usb_gadget_probe_driver+0x31f/0x3f0 drivers/usb/gadget/udc/core.c:1421
 raw_ioctl_run drivers/usb/gadget/legacy/raw_gadget.c:512 [inline]
 raw_ioctl+0x769/0x1cd0 drivers/usb/gadget/legacy/raw_gadget.c:1210
 __do_compat_sys_ioctl fs/ioctl.c:865 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:816 [inline]
 __ia32_compat_sys_ioctl+0x23d/0x2b0 fs/ioctl.c:816
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x270/0xe90 arch/x86/entry/common.c:396
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
Modules linked in:
CR2: 0000000000000000
---[ end trace ad5f3fda17c72903 ]---
RIP: 0010:__read_once_size include/linux/compiler.h:252 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x43/0x60 kernel/kcov.c:202
Code: 24 74 0f 80 e6 01 74 35 8b 90 04 14 00 00 85 d2 74 2b 8b 90 e0 13 00 00 83 fa 02 75 20 48 8b 88 e8 13 00 00 8b 80 e4 13 00 00 <48> 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 66 0f
RSP: 0018:ffffc90000db7960 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff88b2a4c0 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff83b1d0ab RDI: 0000000000000001
RBP: ffffc90000db7a80 R08: ffff888065ac96c0 R09: ffffed1004eb0c2f
R10: ffff888027586174 R11: ffffed1004eb0c2e R12: dffffc0000000000
R13: ffffffff88b2a4c0 R14: 1ffff920001b6f30 R15: 0000000000000055
FS:  0000000000000000(0000) GS:ffff88802cf00000(0063) knlGS:00000000f5d7ab40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000644a8000 CR4: 0000000000340ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/17 12:58 upstream 435faf5c218a b6c46f43 .config console log report ci-qemu-upstream-386
* Struck through repros no longer work on HEAD.