From: Lars Ellenberg Date: Mon, 13 Jun 2016 22:26:18 +0000 (+0200) Subject: drbd: fix for truncated minor number in callback command line X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=0982368bfd59647b4f30415c9ed038f60b859875;p=linux-beck.git drbd: fix for truncated minor number in callback command line The command line parameter the kernel module uses to communicate the device minor to userland helper is flawed in a way that the device indentifier "minor-%d" is being truncated to minors with a maximum of 5 digits. But DRBD 8.4 allows 2^20 == 1048576 minors, thus a minimum of 7 digits must be supported. Reported by Veit Wahlich on drbd-dev. Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe --- diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index 99339dfe4389..3643f9ca5a38 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -343,7 +343,7 @@ int drbd_khelper(struct drbd_device *device, char *cmd) (char[20]) { }, /* address family */ (char[60]) { }, /* address */ NULL }; - char mb[12]; + char mb[14]; char *argv[] = {usermode_helper, cmd, mb, NULL }; struct drbd_connection *connection = first_peer_device(device)->connection; struct sib_info sib; @@ -352,7 +352,7 @@ int drbd_khelper(struct drbd_device *device, char *cmd) if (current == connection->worker.task) set_bit(CALLBACK_PENDING, &connection->flags); - snprintf(mb, 12, "minor-%d", device_to_minor(device)); + snprintf(mb, 14, "minor-%d", device_to_minor(device)); setup_khelper_env(connection, envp); /* The helper may take some time.