From d7312aab230f975b8ec41c0055a17f0d395b7fb5 Mon Sep 17 00:00:00 2001 From: Alexey Khoroshilov Date: Sat, 20 Dec 2014 00:51:26 +0300 Subject: [PATCH] staging: dgnc: implement proper error handling in dgnc_start() dgnc_start() ignores errors in class_create() and device_create() and it does not deallocate resources if dgnc_tty_preinit() fails. The patch implements proper error handling. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov Signed-off-by: Greg Kroah-Hartman --- drivers/staging/dgnc/dgnc_driver.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/drivers/staging/dgnc/dgnc_driver.c b/drivers/staging/dgnc/dgnc_driver.c index ba98ff348112..f610ae1f3a9f 100644 --- a/drivers/staging/dgnc/dgnc_driver.c +++ b/drivers/staging/dgnc/dgnc_driver.c @@ -238,6 +238,7 @@ static int dgnc_start(void) { int rc = 0; unsigned long flags; + struct device *dev; /* make sure that the globals are init'd before we do anything else */ dgnc_init_globals(); @@ -257,9 +258,20 @@ static int dgnc_start(void) dgnc_Major = rc; dgnc_class = class_create(THIS_MODULE, "dgnc_mgmt"); - device_create(dgnc_class, NULL, - MKDEV(dgnc_Major, 0), - NULL, "dgnc_mgmt"); + if (IS_ERR(dgnc_class)) { + rc = PTR_ERR(dgnc_class); + pr_err(DRVSTR ": Can't create dgnc_mgmt class (%d)\n", rc); + goto failed_class; + } + + dev = device_create(dgnc_class, NULL, + MKDEV(dgnc_Major, 0), + NULL, "dgnc_mgmt"); + if (IS_ERR(dev)) { + rc = PTR_ERR(dev); + pr_err(DRVSTR ": Can't create device (%d)\n", rc); + goto failed_device; + } /* * Init any global tty stuff. @@ -268,7 +280,7 @@ static int dgnc_start(void) if (rc < 0) { pr_err(DRVSTR ": tty preinit - not enough memory (%d)\n", rc); - return rc; + goto failed_tty; } /* Start the poller */ @@ -282,6 +294,14 @@ static int dgnc_start(void) add_timer(&dgnc_poll_timer); + return 0; + +failed_tty: + device_destroy(dgnc_class, MKDEV(dgnc_Major, 0)); +failed_device: + class_destroy(dgnc_class); +failed_class: + unregister_chrdev(dgnc_Major, "dgnc"); return rc; } -- 2.34.1