From 703c13fe3c9af557d312f5895ed6a5fda2711104 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 19 Dec 2022 10:10:04 +0100 Subject: efi: fix NULL-deref in init error path In cases where runtime services are not supported or have been disabled, the runtime services workqueue will never have been allocated. Do not try to destroy the workqueue unconditionally in the unlikely event that EFI initialisation fails to avoid dereferencing a NULL pointer. Fixes: 98086df8b70c ("efi: add missed destroy_workqueue when efisubsys_init fails") Cc: stable@vger.kernel.org Cc: Li Heng Signed-off-by: Johan Hovold Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efi.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 09716eebe8ac..a2b0cbc8741c 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -394,8 +394,8 @@ static int __init efisubsys_init(void) efi_kobj = kobject_create_and_add("efi", firmware_kobj); if (!efi_kobj) { pr_err("efi: Firmware registration failed.\n"); - destroy_workqueue(efi_rts_wq); - return -ENOMEM; + error = -ENOMEM; + goto err_destroy_wq; } if (efi_rt_services_supported(EFI_RT_SUPPORTED_GET_VARIABLE | @@ -443,7 +443,10 @@ err_unregister: err_put: kobject_put(efi_kobj); efi_kobj = NULL; - destroy_workqueue(efi_rts_wq); +err_destroy_wq: + if (efi_rts_wq) + destroy_workqueue(efi_rts_wq); + return error; } -- cgit v1.2.3 From e006ac3003080177cf0b673441a4241f77aaecce Mon Sep 17 00:00:00 2001 From: Ding Hui Date: Tue, 27 Dec 2022 23:09:36 +0800 Subject: efi: fix userspace infinite retry read efivars after EFI runtime services page fault After [1][2], if we catch exceptions due to EFI runtime service, we will clear EFI_RUNTIME_SERVICES bit to disable EFI runtime service, then the subsequent routine which invoke the EFI runtime service should fail. But the userspace cat efivars through /sys/firmware/efi/efivars/ will stuck and infinite loop calling read() due to efivarfs_file_read() return -EINTR. The -EINTR is converted from EFI_ABORTED by efi_status_to_err(), and is an improper return value in this situation, so let virt_efi_xxx() return EFI_DEVICE_ERROR and converted to -EIO to invoker. Cc: Fixes: 3425d934fc03 ("efi/x86: Handle page faults occurring while running EFI runtime services") Fixes: 23715a26c8d8 ("arm64: efi: Recover from synchronous exceptions occurring in firmware") Signed-off-by: Ding Hui Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/runtime-wrappers.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c index 7feee3d9c2bf..1fba4e09cdcf 100644 --- a/drivers/firmware/efi/runtime-wrappers.c +++ b/drivers/firmware/efi/runtime-wrappers.c @@ -62,6 +62,7 @@ struct efi_runtime_work efi_rts_work; \ if (!efi_enabled(EFI_RUNTIME_SERVICES)) { \ pr_warn_once("EFI Runtime Services are disabled!\n"); \ + efi_rts_work.status = EFI_DEVICE_ERROR; \ goto exit; \ } \ \ -- cgit v1.2.3