syzbot

vhci_hcd: cannot find a urb of seqnum 0 max seqnum 23
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BUG: KCSAN: data-race in data_push_tail / vsnprintf

write to 0xffffffff86dcf2a5 of 1 bytes by task 29670 on cpu 1:
 vsnprintf+0xe8f/0xed0
 vscnprintf+0x29/0x80 lib/vsprintf.c:2908
 printk_sprint kernel/printk/printk.c:2075 [inline]
 vprintk_store+0x638/0xbb0 kernel/printk/printk.c:2185
 vprintk_emit+0xac/0x3c0 kernel/printk/printk.c:2228
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2255
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x97 kernel/printk/printk.c:2265
 vhci_rx_loop+0x605/0x9a0 drivers/usb/usbip/vhci_rx.c:265
 kthread+0x1bf/0x1e0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30

read to 0xffffffff86dcf2a0 of 8 bytes by task 29672 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:587 [inline]
 data_push_tail+0x138/0x470 kernel/printk/printk_ringbuffer.c:672
 data_alloc+0xbc/0x2b0 kernel/printk/printk_ringbuffer.c:1043
 prb_reserve+0x920/0xbf0 kernel/printk/printk_ringbuffer.c:1549
 vprintk_store+0x560/0xbb0 kernel/printk/printk.c:2175
 vprintk_emit+0xac/0x3c0 kernel/printk/printk.c:2228
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2255
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x97 kernel/printk/printk.c:2265
 vhci_recv_ret_submit drivers/usb/usbip/vhci_rx.c:69 [inline]
 vhci_rx_pdu drivers/usb/usbip/vhci_rx.c:242 [inline]
 vhci_rx_loop+0x2d6/0x9a0 drivers/usb/usbip/vhci_rx.c:265
 kthread+0x1bf/0x1e0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30

value changed: 0x000000010003b851 -> 0x0000006465646573

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 29672 Comm: vhci_rx Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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