tty: mxser: improve error handling in mxser_probe() and mxser_module_init()

1. Currently mxser_probe() and mxser_module_init() ignore errors that can happen in tty_port_register_device(). 2. mxser_module_init() does not deallocate resources allocated in mxser_get_ISA_conf() if mxser_initbrd() failed. The patch adds proper error handling in all the cases. Also it moves free_irq() from mxser_release_ISA_res() to mxser_board_remove(), since it makes mxser_release_ISA_res() a counterpart for mxser_get_ISA_conf(), while free_irq() is relevant to both ISA and PCI boards. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tty: mxser: improve error handling in mxser_probe() and mxser_module_init()
1. Currently mxser_probe() and mxser_module_init() ignore errors that can happen in tty_port_register_device(). 2. mxser_module_init() does not deallocate resources allocated in mxser_get_ISA_conf() if mxser_initbrd() failed. The patch adds proper error handling in all the cases. Also it moves free_irq() from mxser_release_ISA_res() to mxser_board_remove(), since it makes mxser_release_ISA_res() a counterpart for mxser_get_ISA_conf(), while free_irq() is relevant to both ISA and PCI boards. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Alexey Khoroshilov · Greg Kroah-Hartman
1 parent f30e826069
Showing 1 changed file with 35 additions and 7 deletions Side-by-side Diff
drivers/tty/mxser.c
@@ -2364,7 +2364,6 @@
  
 static void mxser_release_ISA_res(struct mxser_board *brd)
 {
-	free_irq(brd->irq, brd);
 	release_region(brd->ports[0].ioaddr, 8 * brd->info->nports);
 	mxser_release_vector(brd);
 }
@@ -2430,6 +2429,7 @@
 		tty_unregister_device(mxvar_sdriver, brd->idx + i);
 		tty_port_destroy(&brd->ports[i].port);
 	}
+	free_irq(brd->irq, brd);
 }
  
 static int __init mxser_get_ISA_conf(int cap, struct mxser_board *brd)
@@ -2554,6 +2554,7 @@
 	struct mxser_board *brd;
 	unsigned int i, j;
 	unsigned long ioaddress;
+	struct device *tty_dev;
 	int retval = -EINVAL;
  
 	for (i = 0; i < MXSER_BOARDS; i++)
  
@@ -2637,13 +2638,25 @@
 	if (retval)
 		goto err_rel3;
  
-	for (i = 0; i < brd->info->nports; i++)
-		tty_port_register_device(&brd->ports[i].port, mxvar_sdriver,
-				brd->idx + i, &pdev->dev);
+	for (i = 0; i < brd->info->nports; i++) {
+		tty_dev = tty_port_register_device(&brd->ports[i].port,
+				mxvar_sdriver, brd->idx + i, &pdev->dev);
+		if (IS_ERR(tty_dev)) {
+			retval = PTR_ERR(tty_dev);
+			for (i--; i >= 0; i--)
+				tty_unregister_device(mxvar_sdriver,
+					brd->idx + i);
+			goto err_relbrd;
+		}
+	}
  
 	pci_set_drvdata(pdev, brd);
  
 	return 0;
+err_relbrd:
+	for (i = 0; i < brd->info->nports; i++)
+		tty_port_destroy(&brd->ports[i].port);
+	free_irq(brd->irq, brd);
 err_rel3:
 	pci_release_region(pdev, 3);
 err_zero:
@@ -2665,7 +2678,6 @@
  
 	mxser_board_remove(brd);
  
-	free_irq(pdev->irq, brd);
 	pci_release_region(pdev, 2);
 	pci_release_region(pdev, 3);
 	pci_disable_device(pdev);
@@ -2683,6 +2695,7 @@
 static int __init mxser_module_init(void)
 {
 	struct mxser_board *brd;
+	struct device *tty_dev;
 	unsigned int b, i, m;
 	int retval;
  
  
  
@@ -2728,14 +2741,29 @@
  
 		/* mxser_initbrd will hook ISR. */
 		if (mxser_initbrd(brd, NULL) < 0) {
+			mxser_release_ISA_res(brd);
 			brd->info = NULL;
 			continue;
 		}
  
 		brd->idx = m * MXSER_PORTS_PER_BOARD;
-		for (i = 0; i < brd->info->nports; i++)
-			tty_port_register_device(&brd->ports[i].port,
+		for (i = 0; i < brd->info->nports; i++) {
+			tty_dev = tty_port_register_device(&brd->ports[i].port,
 					mxvar_sdriver, brd->idx + i, NULL);
+			if (IS_ERR(tty_dev)) {
+				for (i--; i >= 0; i--)
+					tty_unregister_device(mxvar_sdriver,
+						brd->idx + i);
+				for (i = 0; i < brd->info->nports; i++)
+					tty_port_destroy(&brd->ports[i].port);
+				free_irq(brd->irq, brd);
+				mxser_release_ISA_res(brd);
+				brd->info = NULL;
+				break;
+			}
+		}
+		if (brd->info == NULL)
+			continue;
  
 		m++;
 	}
...	...	@@ -2364,7 +2364,6 @@
2364	2364
2365	2365	static void mxser_release_ISA_res(struct mxser_board *brd)
2366	2366	{
2367		- free_irq(brd->irq, brd);
2368	2367	release_region(brd->ports[0].ioaddr, 8 * brd->info->nports);
2369	2368	mxser_release_vector(brd);
2370	2369	}
...	...	@@ -2430,6 +2429,7 @@
2430	2429	tty_unregister_device(mxvar_sdriver, brd->idx + i);
2431	2430	tty_port_destroy(&brd->ports[i].port);
2432	2431	}
	2432	+ free_irq(brd->irq, brd);
2433	2433	}
2434	2434
2435	2435	static int __init mxser_get_ISA_conf(int cap, struct mxser_board *brd)
...	...	@@ -2554,6 +2554,7 @@
2554	2554	struct mxser_board *brd;
2555	2555	unsigned int i, j;
2556	2556	unsigned long ioaddress;
	2557	+ struct device *tty_dev;
2557	2558	int retval = -EINVAL;
2558	2559
2559	2560	for (i = 0; i < MXSER_BOARDS; i++)
2560	2561
...	...	@@ -2637,13 +2638,25 @@
2637	2638	if (retval)
2638	2639	goto err_rel3;
2639	2640
2640		- for (i = 0; i < brd->info->nports; i++)
2641		- tty_port_register_device(&brd->ports[i].port, mxvar_sdriver,
2642		- brd->idx + i, &pdev->dev);
	2641	+ for (i = 0; i < brd->info->nports; i++) {
	2642	+ tty_dev = tty_port_register_device(&brd->ports[i].port,
	2643	+ mxvar_sdriver, brd->idx + i, &pdev->dev);
	2644	+ if (IS_ERR(tty_dev)) {
	2645	+ retval = PTR_ERR(tty_dev);
	2646	+ for (i--; i >= 0; i--)
	2647	+ tty_unregister_device(mxvar_sdriver,
	2648	+ brd->idx + i);
	2649	+ goto err_relbrd;
	2650	+ }
	2651	+ }
2643	2652
2644	2653	pci_set_drvdata(pdev, brd);
2645	2654
2646	2655	return 0;
	2656	+err_relbrd:
	2657	+ for (i = 0; i < brd->info->nports; i++)
	2658	+ tty_port_destroy(&brd->ports[i].port);
	2659	+ free_irq(brd->irq, brd);
2647	2660	err_rel3:
2648	2661	pci_release_region(pdev, 3);
2649	2662	err_zero:
...	...	@@ -2665,7 +2678,6 @@
2665	2678
2666	2679	mxser_board_remove(brd);
2667	2680
2668		- free_irq(pdev->irq, brd);
2669	2681	pci_release_region(pdev, 2);
2670	2682	pci_release_region(pdev, 3);
2671	2683	pci_disable_device(pdev);
...	...	@@ -2683,6 +2695,7 @@
2683	2695	static int __init mxser_module_init(void)
2684	2696	{
2685	2697	struct mxser_board *brd;
	2698	+ struct device *tty_dev;
2686	2699	unsigned int b, i, m;
2687	2700	int retval;
2688	2701
2689	2702
2690	2703
...	...	@@ -2728,14 +2741,29 @@
2728	2741
2729	2742	/* mxser_initbrd will hook ISR. */
2730	2743	if (mxser_initbrd(brd, NULL) < 0) {
	2744	+ mxser_release_ISA_res(brd);
2731	2745	brd->info = NULL;
2732	2746	continue;
2733	2747	}
2734	2748
2735	2749	brd->idx = m * MXSER_PORTS_PER_BOARD;
2736		- for (i = 0; i < brd->info->nports; i++)
2737		- tty_port_register_device(&brd->ports[i].port,
	2750	+ for (i = 0; i < brd->info->nports; i++) {
	2751	+ tty_dev = tty_port_register_device(&brd->ports[i].port,
2738	2752	mxvar_sdriver, brd->idx + i, NULL);
	2753	+ if (IS_ERR(tty_dev)) {
	2754	+ for (i--; i >= 0; i--)
	2755	+ tty_unregister_device(mxvar_sdriver,
	2756	+ brd->idx + i);
	2757	+ for (i = 0; i < brd->info->nports; i++)
	2758	+ tty_port_destroy(&brd->ports[i].port);
	2759	+ free_irq(brd->irq, brd);
	2760	+ mxser_release_ISA_res(brd);
	2761	+ brd->info = NULL;
	2762	+ break;
	2763	+ }
	2764	+ }
	2765	+ if (brd->info == NULL)
	2766	+ continue;
2739	2767
2740	2768	m++;
2741	2769	}