Once device_register() failed, we should call put_device() to decrement reference count for cleanup. Or it could cause memory leak.
As comment of device_register() says, 'NOTE: _Never_ directly free @dev after calling this function, even if it returned an error! Always use put_device() to give up the reference initialized in this function instead.'
Found by code review. Cc: stable@vger.kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Ma Ke make24@iscas.ac.cn --- Changes in v5: - modified the bug description as suggestions; Changes in v4: - deleted the redundant initialization; Changes in v3: - modified the patch as suggestions; Changes in v2: - modified the patch as suggestions. --- arch/arm/common/locomo.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-)
diff --git a/arch/arm/common/locomo.c b/arch/arm/common/locomo.c index cb6ef449b987..45106066a17f 100644 --- a/arch/arm/common/locomo.c +++ b/arch/arm/common/locomo.c @@ -223,10 +223,8 @@ locomo_init_one_child(struct locomo *lchip, struct locomo_dev_info *info) int ret;
dev = kzalloc(sizeof(struct locomo_dev), GFP_KERNEL); - if (!dev) { - ret = -ENOMEM; - goto out; - } + if (!dev) + return -ENOMEM;
/* * If the parent device has a DMA mask associated with it, @@ -254,10 +252,9 @@ locomo_init_one_child(struct locomo *lchip, struct locomo_dev_info *info) NO_IRQ : lchip->irq_base + info->irq[0];
ret = device_register(&dev->dev); - if (ret) { - out: - kfree(dev); - } + if (ret) + put_device(&dev->dev); + return ret; }