From: Anssi Hannula anssi.hannula@bitwise.fi

xhci_decode_usbsts() is expected to return a zero-terminated string by its only caller, xhci_stop_endpoint_command_watchdog(), which directly logs the return value:

xhci_warn(xhci, "USBSTS:%s\n", xhci_decode_usbsts(str, usbsts));

However, if no recognized bits are set in usbsts, the function will return without having called any sprintf() and therefore return an untouched non-zero-terminated caller-provided buffer, causing garbage to be output to log.

Fix that by always including the raw value in the output.

Note that before commit 4843b4b5ec64 ("xhci: fix even more unsafe memory usage in xhci tracing") the result effect in the failure case was different as a static buffer was used here, but the code still worked incorrectly.

Fixes: 9c1aa36efdae ("xhci: Show host status when watchdog triggers and host is assumed dead.") Cc: stable@vger.kernel.org Signed-off-by: Anssi Hannula anssi.hannula@bitwise.fi Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com --- drivers/usb/host/xhci.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index fce32f8ea9d0..1d83ddace482 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -2625,8 +2625,11 @@ static inline const char *xhci_decode_usbsts(char *str, u32 usbsts) { int ret = 0;

+ ret = sprintf(str, " 0x%08x", usbsts); + if (usbsts == ~(u32)0) - return " 0xffffffff"; + return str; + if (usbsts & STS_HALT) ret += sprintf(str + ret, " HCHalted"); if (usbsts & STS_FATAL)