From: Andy Shevchenko andriy.shevchenko@linux.intel.com

stable inclusion from stable-v5.10.198 commit e14afa4450cb7e4cf93e993a765801203d41d014 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I95ATO CVE: CVE-2023-52567

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

--------------------------------

commit cce7fc8b29961b64fadb1ce398dc5ff32a79643b upstream.

In case the leaf driver wants to use IRQ polling (irq = 0) and IIR register shows that an interrupt happened in the 8250 hardware the IRQ data can be NULL. In such a case we need to skip the wake event as we came to this path from the timer interrupt and quite likely system is already awake.

Without this fix we have got an Oops:

serial8250: ttyS0 at I/O 0x3f8 (irq = 0, base_baud = 115200) is a 16550A ... BUG: kernel NULL pointer dereference, address: 0000000000000010 RIP: 0010:serial8250_handle_irq+0x7c/0x240 Call Trace: ? serial8250_handle_irq+0x7c/0x240 ? __pfx_serial8250_timeout+0x10/0x10

Fixes: 0ba9e3a13c6a ("serial: 8250: Add missing wakeup event reporting") Cc: stable stable@kernel.org Signed-off-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Reviewed-by: Florian Fainelli florian.fainelli@broadcom.com Link: https://lore.kernel.org/r/20230831222555.614426-1-andriy.shevchenko@linux.in... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yi Yang yiyang13@huawei.com --- drivers/tty/serial/8250/8250_port.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index b19908779e3b..6218ebc4427d 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -1914,7 +1914,10 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) skip_rx = true;

if (status & (UART_LSR_DR | UART_LSR_BI) && !skip_rx) { - if (irqd_is_wakeup_set(irq_get_irq_data(port->irq))) + struct irq_data *d; + + d = irq_get_irq_data(port->irq); + if (d && irqd_is_wakeup_set(d)) pm_wakeup_event(tport->tty->dev, 0); if (!up->dma || handle_rx_dma(up, iir)) status = serial8250_rx_chars(up, status);