Hello,
syzbot has tested the proposed patch but the reproducer still triggered
crash:
WARNING in yurex_write/usb_submit_urb
------------[ cut here ]------------
URB 00000000c866c77d submitted while active
WARNING: CPU: 1 PID: 2816 at drivers/usb/core/urb.c:362
usb_submit_urb+0x10c1/0x13b0 drivers/usb/core/urb.c:362
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 2816 Comm: syz-executor.4 Not tainted 5.3.0-rc4+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xca/0x13e lib/dump_stack.c:113
panic+0x2a3/0x6da kernel/panic.c:219
__warn.cold+0x20/0x4a kernel/panic.c:576
report_bug+0x262/0x2a0 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:179 [inline]
fixup_bug arch/x86/kernel/traps.c:174 [inline]
do_error_trap+0x12b/0x1e0 arch/x86/kernel/traps.c:272
do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:291
invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028
RIP: 0010:usb_submit_urb+0x10c1/0x13b0 drivers/usb/core/urb.c:362
Code: 89 de e8 62 b7 ef fd 84 db 0f 85 42 f6 ff ff e8 25 b6 ef fd 4c 89 fe
48 c7 c7 c0 67 18 86 c6 05 07 29 3a 04 01 e8 14 9b c5 fd <0f> 0b e9 20 f6
ff ff c7 44 24 14 01 00 00 00 e9 d7 f6 ff ff 41 bd
RSP: 0018:ffff8881c6f3fc48 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81288cfd RDI: ffffed1038de7f7b
RBP: ffff8881d1210000 R08: ffff8881c726c800 R09: fffffbfff11ad3a4
R10: fffffbfff11ad3a3 R11: ffffffff88d69d1f R12: 1ffff11038de7f9f
R13: 00000000fffffff0 R14: 0000000000000000 R15: ffff8881d63eff00
yurex_write+0x369/0x8f0 drivers/usb/misc/yurex.c:493
__vfs_write+0x76/0x100 fs/read_write.c:494
vfs_write+0x262/0x5c0 fs/read_write.c:558
ksys_write+0x127/0x250 fs/read_write.c:611
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459829
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f5fe5e65c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
RDX: 000000000000008d RSI: 0000000020000040 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5fe5e666d4
R13: 00000000004c99b9 R14: 00000000004e1038 R15: 00000000ffffffff
Kernel Offset: disabled
Rebooting in 86400 seconds..
Tested on:
commit: d0847550 usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git
console output: https://syzkaller.appspot.com/x/log.txt?x=16026986600000
kernel config: https://syzkaller.appspot.com/x/.config?x=dbc9c80cc095da19
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
patch: https://syzkaller.appspot.com/x/patch.diff?x=14fe315a600000
