From: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx> [ Upstream commit e3436ce60cf5f5eaedda2b8c622f69feb97595e2 ] gasket_sysfs_register_store() invokes get_mapping(), which returns a reference of the specified gasket_sysfs_mapping object to "mapping" with increased refcnt. When gasket_sysfs_register_store() returns, local variable "mapping" becomes invalid, so the refcount should be decreased to keep refcount balanced. The reference counting issue happens in one exception handling path of gasket_sysfs_register_store(). When gasket_dev is NULL, the function forgets to decrease the refcnt increased by get_mapping(), causing a refcnt leak. Fix this issue by calling put_mapping() when gasket_dev is NULL. Signed-off-by: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx> Signed-off-by: Xin Tan <tanxin.ctf@xxxxxxxxx> Link: https://lore.kernel.org/r/1587618941-13718-1-git-send-email-xiyuyang19@xxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/staging/gasket/gasket_sysfs.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/staging/gasket/gasket_sysfs.c b/drivers/staging/gasket/gasket_sysfs.c index 9c982f1c0881..5986c67bc7ec 100644 --- a/drivers/staging/gasket/gasket_sysfs.c +++ b/drivers/staging/gasket/gasket_sysfs.c @@ -377,6 +377,7 @@ ssize_t gasket_sysfs_register_store(struct device *device, gasket_dev = mapping->gasket_dev; if (!gasket_dev) { dev_err(device, "Device driver may have been removed\n"); + put_mapping(mapping); return 0; } -- 2.25.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
