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Since rx_dma_buf > is allocated with UART_XMIT_SIZE (4096 bytes), a hardware fault or > compromised peripheral reporting a count larger than 4096 would cause > an out-of-bounds read, potentially leaking kernel memory. > > Clamp the count to UART_XMIT_SIZE before use. > > Assisted-by: opencode:big-pickle > Signed-off-by: Rosen Penev > --- > drivers/tty/serial/mxs-auart.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c > index e2b656638ab3..fe48a372d022 100644 > --- a/drivers/tty/serial/mxs-auart.c > +++ b/drivers/tty/serial/mxs-auart.c > @@ -823,7 +823,7 @@ static void dma_rx_callback(void *arg) > stat &= ~(AUART_STAT_OERR | AUART_STAT_BERR | > AUART_STAT_PERR | AUART_STAT_FERR); > > - count = stat & AUART_STAT_RXCOUNT_MASK; > + count = min_t(u32, stat & AUART_STAT_RXCOUNT_MASK, UART_XMIT_SIZE); Now, needn't min_t(), min() should work Frank > tty_insert_flip_string(port, s->rx_dma_buf, count); > > mxs_write(stat, s, REG_STAT); > -- > 2.54.0 > >