[PATCH v2 7/7] serial: exar: fix: fix crash during shutdown if setup fails

parker
2024-04-11T20:26:04Z

From: Parker Newman <pnewman@connecttech.com>

If a port fails to register with serial8250_register_8250_port the
kernel can crash when shutting down or module removal.

This is because "priv->line[i]" will be set to a negative error code
andin the exar_pci_remove function serial8250_unregister_port is called
without checking if the "priv->line[i]" value is valid.

Signed-off-by: Parker Newman <pnewman@connecttech.com>
---
drivers/tty/serial/8250/8250_exar.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/8250/8250_exar.c b/drivers/tty/serial/8250/8250_exar.c
index d8425113a9f1..1c6343ed76e9 100644
--- a/drivers/tty/serial/8250/8250_exar.c
+++ b/drivers/tty/serial/8250/8250_exar.c
@@ -1675,7 +1675,8 @@ static void exar_pci_remove(struct pci_dev *pcidev)
unsigned int i;

for (i = 0; i < priv->nr; i++)
- serial8250_unregister_port(priv->line[i]);
+ if (priv->line[i] >= 0)
+ serial8250_unregister_port(priv->line[i]);

/* Ensure that every init quirk is properly torn down */
if (priv->board->exit)
--
2.43.2