6.9-stable review patch. If anyone has any objections, please let me know.
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From: Damien Le Moal dlemoal@kernel.org
[ Upstream commit d9ff882b54f99f96787fa3df7cd938966843c418 ]
When powering on a null_blk device that is not already on, the return value ret that is initialized to be count is reused to check the return value of null_add_dev(), leading to nullb_device_power_store() to return null_add_dev() return value (0 on success) instead of "count". So make sure to set ret to be equal to count when there are no errors.
Fixes: a2db328b0839 ("null_blk: fix null-ptr-dereference while configuring 'power' and 'submit_queues'") Signed-off-by: Damien Le Moal dlemoal@kernel.org Reviewed-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Kanchan Joshi joshi.k@samsung.com Link: https://lore.kernel.org/r/20240527043445.235267-1-dlemoal@kernel.org Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/null_blk/main.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c index 3b3fd093b0044..620679a0ac381 100644 --- a/drivers/block/null_blk/main.c +++ b/drivers/block/null_blk/main.c @@ -483,6 +483,7 @@ static ssize_t nullb_device_power_store(struct config_item *item,
set_bit(NULLB_DEV_FL_CONFIGURED, &dev->flags); dev->power = newp; + ret = count; } else if (dev->power && !newp) { if (test_and_clear_bit(NULLB_DEV_FL_UP, &dev->flags)) { dev->power = newp;