On Tue, Feb 21, 2023 at 02:04:49AM +0800, wenyang.linux@foxmail.com wrote:
From: Zhang Wensheng zhangwensheng5@huawei.com
commit 858f1bf65d3d9c00b5e2d8ca87dc79ed88267c98 upstream.
When 'index' is a big numbers, it may become negative which forced to 'int'. then 'index << part_shift' might overflow to a positive value that is not greater than '0xfffff', then sysfs might complains about duplicate creation. Because of this, move the 'index' judgment to the front will fix it and be better.
Fixes: b0d9111a2d53 ("nbd: use an idr to keep track of nbd devices") Fixes: 940c264984fd ("nbd: fix possible overflow for 'first_minor' in nbd_dev_add()") Signed-off-by: Zhang Wensheng zhangwensheng5@huawei.com Signed-off-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Josef Bacik josef@toxicpanda.com Link: https://lore.kernel.org/r/20220521073749.3146892-6-yukuai3@huawei.com Signed-off-by: Jens Axboe axboe@kernel.dk Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Wen Yang wenyang.linux@foxmail.com
drivers/block/nbd.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-)
This is also needed in 5.15.y, please be more careful, you do not want to have a regression when moving to a newer kernel version.
I've queued it up there as well.
thanks,
greg k-h