From 7ff684a683d777c4956fce93e60accbab2bd7696 Mon Sep 17 00:00:00 2001 From: John Pittman Date: Fri, 5 Apr 2019 17:42:45 -0400 Subject: null_blk: prevent crash from bad home_node value At module load, if the selected home_node value is greater than the available numa nodes, the system will crash in __alloc_pages_nodemask() due to a bad paging request. Prevent this user error crash by detecting the bad value, logging an error, and setting g_home_node back to the default of NUMA_NO_NODE. Signed-off-by: John Pittman Signed-off-by: Jens Axboe --- drivers/block/null_blk_main.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/block/null_blk_main.c') diff --git a/drivers/block/null_blk_main.c b/drivers/block/null_blk_main.c index 417a9f15c116..d7ac09c092f2 100644 --- a/drivers/block/null_blk_main.c +++ b/drivers/block/null_blk_main.c @@ -1748,6 +1748,11 @@ static int __init null_init(void) return -EINVAL; } + if (g_home_node != NUMA_NO_NODE && g_home_node >= nr_online_nodes) { + pr_err("null_blk: invalid home_node value\n"); + g_home_node = NUMA_NO_NODE; + } + if (g_queue_mode == NULL_Q_RQ) { pr_err("null_blk: legacy IO path no longer available\n"); return -EINVAL; -- cgit v1.2.3-55-g7522