From: Lv Yunlong lyl2019@mail.ustc.edu.cn
stable inclusion from linux-4.19.198 commit 481a76d4749ee3a27f902ba213fdcbb4bb39720e
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[ Upstream commit 7272b591c4cb9327c43443f67b8fbae7657dd9ae ]
In ibmasm_init_one, it calls ibmasm_init_remote_input_dev(). Inside ibmasm_init_remote_input_dev, mouse_dev and keybd_dev are allocated by input_allocate_device(), and assigned to sp->remote.mouse_dev and sp->remote.keybd_dev respectively.
In the err_free_devices error branch of ibmasm_init_one, mouse_dev and keybd_dev are freed by input_free_device(), and return error. Then the execution runs into error_send_message error branch of ibmasm_init_one, where ibmasm_free_remote_input_dev(sp) is called to unregister the freed sp->remote.mouse_dev and sp->remote.keybd_dev.
My patch add a "error_init_remote" label to handle the error of ibmasm_init_remote_input_dev(), to avoid the uaf bugs.
Signed-off-by: Lv Yunlong lyl2019@mail.ustc.edu.cn Link: https://lore.kernel.org/r/20210426170620.10546-1-lyl2019@mail.ustc.edu.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/misc/ibmasm/module.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/misc/ibmasm/module.c b/drivers/misc/ibmasm/module.c index e914b8c809433..9f8344169845c 100644 --- a/drivers/misc/ibmasm/module.c +++ b/drivers/misc/ibmasm/module.c @@ -125,7 +125,7 @@ static int ibmasm_init_one(struct pci_dev *pdev, const struct pci_device_id *id) result = ibmasm_init_remote_input_dev(sp); if (result) { dev_err(sp->dev, "Failed to initialize remote queue\n"); - goto error_send_message; + goto error_init_remote; }
result = ibmasm_send_driver_vpd(sp); @@ -145,8 +145,9 @@ static int ibmasm_init_one(struct pci_dev *pdev, const struct pci_device_id *id) return 0;
error_send_message: - disable_sp_interrupts(sp->base_address); ibmasm_free_remote_input_dev(sp); +error_init_remote: + disable_sp_interrupts(sp->base_address); free_irq(sp->irq, (void *)sp); error_request_irq: iounmap(sp->base_address);