From: =?UTF-8?q?Timo=20Schl=C3=BC=C3=9Fler?= <schluessler@krause.de>
Date: Fri, 11 Oct 2019 15:38:19 +0200
Subject: can: mcp251x: mcp251x_restart_work_handler(): Fix potential
 force_quit race condition
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Git-commit: 27a0e54bae09d2dd023a01254db506d61cc50ba1
Patch-mainline: 5.4-rc7
References: bnc#1151927 5.3.15

In mcp251x_restart_work_handler() the variable to stop the interrupt
handler (priv->force_quit) is reset after the chip is restarted and thus
a interrupt might occur.

This patch fixes the potential race condition by resetting force_quit
before enabling interrupts.

Signed-off-by: Timo Schlüßler <schluessler@krause.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/net/can/spi/mcp251x.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/can/spi/mcp251x.c
+++ b/drivers/net/can/spi/mcp251x.c
@@ -759,6 +759,7 @@ static void mcp251x_restart_work_handler
 	if (priv->after_suspend) {
 		mcp251x_hw_reset(spi);
 		mcp251x_setup(net, spi);
+		priv->force_quit = 0;
 		if (priv->after_suspend & AFTER_SUSPEND_RESTART) {
 			mcp251x_set_normal_mode(spi);
 		} else if (priv->after_suspend & AFTER_SUSPEND_UP) {
@@ -770,7 +771,6 @@ static void mcp251x_restart_work_handler
 			mcp251x_hw_sleep(spi);
 		}
 		priv->after_suspend = 0;
-		priv->force_quit = 0;
 	}
 
 	if (priv->restart_tx) {