This is a note to let you know that I've just added the patch titled misc/libmasm/module: Fix two use after free in ibmasm_init_one to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: misc-libmasm-module-fix-two-use-after-free-in-ibmasm.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ca1bdaa86f82d0be6932055030a698a732db37b9 Author: Lv Yunlong <lyl2019@xxxxxxxxxxxxxxxx> Date: Mon Apr 26 10:06:20 2021 -0700 misc/libmasm/module: Fix two use after free in ibmasm_init_one [ 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@xxxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210426170620.10546-1-lyl2019@xxxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/misc/ibmasm/module.c b/drivers/misc/ibmasm/module.c index e914b8c80943..9f8344169845 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);