AuxXxilium/linux_dsm_epyc7002
1
0
Fork 0
mirror of https://github.com/AuxXxilium/linux_dsm_epyc7002.git synced 2024-12-14 16:36:55 +07:00
Code Issues Actions Packages Projects Releases Wiki Activity

tty/serial: atmel: fix race condition (TX+DMA)

Browse Source 
If uart_flush_buffer() is called between atmel_tx_dma() and
atmel_complete_tx_dma(), the circular buffer has been cleared, but not
atmel_port->tx_len.
That leads to a circular buffer overflow (dumping (UART_XMIT_SIZE -
atmel_port->tx_len) bytes).

Tested-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Cc: stable <stable@vger.kernel.org> # 3.12+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Richard Genoud 2017-03-20 11:52:41 +01:00 committed by Greg Kroah-Hartman
parent a6040bc610
commit 31ca2c63fd
1 changed files with 5 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/tty/serial/atmel_serial.c
View File

@ -1951,6 +1951,11 @@ static void atmel_flush_buffer(struct uart_port *port)
atmel_uart_writel(port, ATMEL_PDC_TCR, 0);
atmel_port->pdc_tx.ofs = 0;
}
/*
* in uart_flush_buffer(), the xmit circular buffer has just
* been cleared, so we have to reset tx_len accordingly.
*/
atmel_port->tx_len = 0;
}
/*