[PATCH 08/10] efi/libstub: use stricter typing for firmware function pointers

From: Ard Biesheuvel
Date: Sat Dec 14 2019 - 12:58:06 EST


We will soon remove another level of pointer casting, so let's make
sure all type handling involving firmware calls at boot time is correct.

Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
arch/x86/boot/compressed/eboot.c | 10 ++++++----
arch/x86/boot/compressed/eboot.h | 5 +++--
drivers/firmware/efi/libstub/efi-stub-helper.c | 5 +++--
drivers/firmware/efi/libstub/tpm.c | 4 ++--
include/linux/efi.h | 6 +++++-
5 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 6d833f93a878..052852eaa076 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -64,7 +64,8 @@ preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)

size = romsize + sizeof(*rom);

- status = efi_call_early(allocate_pool, EFI_LOADER_DATA, size, &rom);
+ status = efi_call_early(allocate_pool, EFI_LOADER_DATA, size,
+ (void **)&rom);
if (status != EFI_SUCCESS) {
efi_printk(sys_table, "Failed to allocate memory for 'rom'\n");
return status;
@@ -191,9 +192,9 @@ static void retrieve_apple_device_properties(struct boot_params *boot_params)
struct setup_data *data, *new;
efi_status_t status;
u32 size = 0;
- void *p;
+ apple_properties_protocol_t *p;

- status = efi_call_early(locate_protocol, &guid, NULL, &p);
+ status = efi_call_early(locate_protocol, &guid, NULL, (void **)&p);
if (status != EFI_SUCCESS)
return;

@@ -208,7 +209,8 @@ static void retrieve_apple_device_properties(struct boot_params *boot_params)

do {
status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
- size + sizeof(struct setup_data), &new);
+ size + sizeof(struct setup_data),
+ (void **)&new);
if (status != EFI_SUCCESS) {
efi_printk(sys_table, "Failed to allocate memory for 'properties'\n");
return;
diff --git a/arch/x86/boot/compressed/eboot.h b/arch/x86/boot/compressed/eboot.h
index 1cf384ba1b0e..318531f128c2 100644
--- a/arch/x86/boot/compressed/eboot.h
+++ b/arch/x86/boot/compressed/eboot.h
@@ -18,8 +18,9 @@ typedef struct {
u32 blt;
} efi_uga_draw_protocol_32_t;

-typedef struct {
- void *get_mode;
+typedef struct efi_uga_draw_protocol {
+ efi_status_t (*get_mode)(struct efi_uga_draw_protocol *,
+ u32*, u32*, u32*, u32*);
void *set_mode;
void *blt;
} efi_uga_draw_protocol_t;
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index ff3266b9f673..5bb1715cb154 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -423,12 +423,13 @@ static efi_status_t efi_file_size(efi_system_table_t *sys_table_arg, void *__fh,
return status;
}

-static efi_status_t efi_file_read(void *handle, unsigned long *size, void *addr)
+static efi_status_t efi_file_read(efi_file_handle_t *handle,
+ unsigned long *size, void *addr)
{
return efi_call_proto(efi_file_handle, read, handle, size, addr);
}

-static efi_status_t efi_file_close(void *handle)
+static efi_status_t efi_file_close(efi_file_handle_t *handle)
{
return efi_call_proto(efi_file_handle, close, handle);
}
diff --git a/drivers/firmware/efi/libstub/tpm.c b/drivers/firmware/efi/libstub/tpm.c
index 0354d35ebaa7..83cf204bfe8f 100644
--- a/drivers/firmware/efi/libstub/tpm.c
+++ b/drivers/firmware/efi/libstub/tpm.c
@@ -59,11 +59,11 @@ void efi_retrieve_tpm2_eventlog(efi_system_table_t *sys_table_arg)
size_t log_size, last_entry_size;
efi_bool_t truncated;
int version = EFI_TCG2_EVENT_LOG_FORMAT_TCG_2;
- void *tcg2_protocol = NULL;
+ efi_tcg2_protocol_t *tcg2_protocol = NULL;
int final_events_size = 0;

status = efi_call_early(locate_protocol, &tcg2_guid, NULL,
- &tcg2_protocol);
+ (void **)&tcg2_protocol);
if (status != EFI_SUCCESS)
return;

diff --git a/include/linux/efi.h b/include/linux/efi.h
index 87c2537b4543..7f1a99bd2c05 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -399,7 +399,11 @@ struct efi_pci_io_protocol {
void *allocate_buffer;
void *free_buffer;
void *flush;
- void *get_location;
+ efi_status_t (*get_location)(struct efi_pci_io_protocol *,
+ unsigned long *segment_nr,
+ unsigned long *bus_nr,
+ unsigned long *device_nr,
+ unsigned long *function_nr);
void *attributes;
void *get_bar_attributes;
void *set_bar_attributes;
--
2.17.1