From: Tejun Heo Date: Thu, 8 Nov 2007 07:00:24 +0000 (+0100) Subject: pktcdvd: fix BUG caused by sysfs module reference semantics change X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=fffe487d59ba4017c7c62b06667ca4a226cee651;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git pktcdvd: fix BUG caused by sysfs module reference semantics change pkt_setup_dev() expects module reference to be held on invocation. This used to be true for sysfs callbacks but not anymore. Test and grab module reference around pkt_setup_dev() in class_pktcdvd_store_add(). Signed-off-by: Tejun Heo Acked-by: Peter Osterlund Signed-off-by: Jens Axboe --- diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c index a8130a4ad6d4..a5ee21319d37 100644 --- a/drivers/block/pktcdvd.c +++ b/drivers/block/pktcdvd.c @@ -358,10 +358,19 @@ static ssize_t class_pktcdvd_store_add(struct class *c, const char *buf, size_t count) { unsigned int major, minor; + if (sscanf(buf, "%u:%u", &major, &minor) == 2) { + /* pkt_setup_dev() expects caller to hold reference to self */ + if (!try_module_get(THIS_MODULE)) + return -ENODEV; + pkt_setup_dev(MKDEV(major, minor), NULL); + + module_put(THIS_MODULE); + return count; } + return -EINVAL; }