2016-12-01 02:52:22

by Pan Bian

[permalink] [raw]
Subject: [PATCH 1/1] block: nbd: fix bugs in nbd_init

Fix bug https://bugzilla.kernel.org/show_bug.cgi?id=188441. Fix 3 bugs
in function nbd_init: (1) set error code (-ENOMEM) when the call to
alloc_disk() fails; (2) function blk_mq_init_queue() returns an
ERR_PTR pointer rather than NULL on failures, so use IS_ERR to check the
return value; (3) set error code on the branch that blk_mq_init_queue()
returns an invalid pointer.

Signed-off-by: Pan Bian <[email protected]>
---
drivers/block/nbd.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 7a10487..200e899 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -930,8 +930,10 @@ static int __init nbd_init(void)

for (i = 0; i < nbds_max; i++) {
struct gendisk *disk = alloc_disk(1 << part_shift);
- if (!disk)
+ if (!disk) {
+ err = -ENOMEM;
goto out;
+ }
nbd_dev[i].disk = disk;

nbd_dev[i].tag_set.ops = &nbd_mq_ops;
@@ -955,7 +957,8 @@ static int __init nbd_init(void)
* These structs are big so we dynamically allocate them.
*/
disk->queue = blk_mq_init_queue(&nbd_dev[i].tag_set);
- if (!disk->queue) {
+ if (IS_ERR(disk->queue)) {
+ err = PTR_ERR(disk->queue);
blk_mq_free_tag_set(&nbd_dev[i].tag_set);
put_disk(disk);
goto out;
--
1.9.1