efi/libstub: Use cleanup helpers for freeing copies of the memory map

The EFI stub may obtain the memory map from the firmware numerous times,
and this involves doing a EFI pool allocation first, which needs to be
freed after use.

Streamline this using a cleanup helper, which makes the code easier to
follow.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

diff --git a/drivers/firmware/efi/libstub/kaslr.c b/drivers/firmware/efi/libstub/kaslr.c
index 6318c40bda38a75a78ce7c4e93d3d529d70588e5..4bc963e999eb97394aacca1094e800361eb6ab91 100644 (file)
--- a/drivers/firmware/efi/libstub/kaslr.c
+++ b/drivers/firmware/efi/libstub/kaslr.c
@@ -57,7 +57,7 @@ u32 efi_kaslr_get_phys_seed(efi_handle_t image_handle)
  */
 static bool check_image_region(u64 base, u64 size)
 {
-       struct efi_boot_memmap *map;
+       struct efi_boot_memmap *map __free(efi_pool) = NULL;
        efi_status_t status;
        bool ret = false;
        int map_offset;
@@ -80,8 +80,6 @@ static bool check_image_region(u64 base, u64 size)
                }
        }
 
-       efi_bs_call(free_pool, map);
-
        return ret;
 }
 

diff --git a/drivers/firmware/efi/libstub/mem.c b/drivers/firmware/efi/libstub/mem.c
index 4f1fa302234d880f68c4f63e92d3326c3cd4dd29..9c82259eea8166b86e01d262e3d74051bc57fc72 100644 (file)
--- a/drivers/firmware/efi/libstub/mem.c
+++ b/drivers/firmware/efi/libstub/mem.c
@@ -20,10 +20,10 @@
 efi_status_t efi_get_memory_map(struct efi_boot_memmap **map,
                                bool install_cfg_tbl)
 {
+       struct efi_boot_memmap tmp, *m __free(efi_pool) = NULL;
        int memtype = install_cfg_tbl ? EFI_ACPI_RECLAIM_MEMORY
                                      : EFI_LOADER_DATA;
        efi_guid_t tbl_guid = LINUX_EFI_BOOT_MEMMAP_GUID;
-       struct efi_boot_memmap *m, tmp;
        efi_status_t status;
        unsigned long size;
 
@@ -48,24 +48,20 @@ efi_status_t efi_get_memory_map(struct efi_boot_memmap **map,
                 */
                status = efi_bs_call(install_configuration_table, &tbl_guid, m);
                if (status != EFI_SUCCESS)
-                       goto free_map;
+                       return status;
        }
 
        m->buff_size = m->map_size = size;
        status = efi_bs_call(get_memory_map, &m->map_size, m->map, &m->map_key,
                             &m->desc_size, &m->desc_ver);
-       if (status != EFI_SUCCESS)
-               goto uninstall_table;
+       if (status != EFI_SUCCESS) {
+               if (install_cfg_tbl)
+                       efi_bs_call(install_configuration_table, &tbl_guid, NULL);
+               return status;
+       }
 
-       *map = m;
+       *map = no_free_ptr(m);
        return EFI_SUCCESS;
-
-uninstall_table:
-       if (install_cfg_tbl)
-               efi_bs_call(install_configuration_table, &tbl_guid, NULL);
-free_map:
-       efi_bs_call(free_pool, m);
-       return status;
 }
 
 /**

diff --git a/drivers/firmware/efi/libstub/randomalloc.c b/drivers/firmware/efi/libstub/randomalloc.c
index c41e7b2091cdd1615f3507f7d186d5893ff683e0..e5872e38d9a46900c7c63050336b8bed08282763 100644 (file)
--- a/drivers/firmware/efi/libstub/randomalloc.c
+++ b/drivers/firmware/efi/libstub/randomalloc.c
@@ -59,9 +59,9 @@ efi_status_t efi_random_alloc(unsigned long size,
                              unsigned long alloc_min,
                              unsigned long alloc_max)
 {
+       struct efi_boot_memmap *map __free(efi_pool) = NULL;
        unsigned long total_slots = 0, target_slot;
        unsigned long total_mirrored_slots = 0;
-       struct efi_boot_memmap *map;
        efi_status_t status;
        int map_offset;
 
@@ -130,7 +130,5 @@ efi_status_t efi_random_alloc(unsigned long size,
                break;
        }
 
-       efi_bs_call(free_pool, map);
-
        return status;
 }

diff --git a/drivers/firmware/efi/libstub/relocate.c b/drivers/firmware/efi/libstub/relocate.c
index d694bcfa1074e93a99e6f47883f812de382033fe..99b45d1cd62462ea0e8ff8d94b982fd62afeb593 100644 (file)
--- a/drivers/firmware/efi/libstub/relocate.c
+++ b/drivers/firmware/efi/libstub/relocate.c
@@ -23,14 +23,14 @@
 efi_status_t efi_low_alloc_above(unsigned long size, unsigned long align,
                                 unsigned long *addr, unsigned long min)
 {
-       struct efi_boot_memmap *map;
+       struct efi_boot_memmap *map __free(efi_pool) = NULL;
        efi_status_t status;
        unsigned long nr_pages;
        int i;
 
        status = efi_get_memory_map(&map, false);
        if (status != EFI_SUCCESS)
-               goto fail;
+               return status;
 
        /*
         * Enforce minimum alignment that EFI or Linux requires when
@@ -79,11 +79,9 @@ efi_status_t efi_low_alloc_above(unsigned long size, unsigned long align,
        }
 
        if (i == map->map_size / map->desc_size)
-               status = EFI_NOT_FOUND;
+               return EFI_NOT_FOUND;
 
-       efi_bs_call(free_pool, map);
-fail:
-       return status;
+       return EFI_SUCCESS;
 }
 
 /**

diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index 014ccf36a065a66f9dc71e33a38601dc43c535bb..893c3ce4f4cc9bb000d1046bb700b3f968e59411 100644 (file)
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -616,7 +616,7 @@ static efi_status_t allocate_e820(struct boot_params *params,
                                  struct setup_data **e820ext,
                                  u32 *e820ext_size)
 {
-       struct efi_boot_memmap *map;
+       struct efi_boot_memmap *map __free(efi_pool) = NULL;
        efi_status_t status;
        __u32 nr_desc;
 
@@ -630,13 +630,14 @@ static efi_status_t allocate_e820(struct boot_params *params,
                                 EFI_MMAP_NR_SLACK_SLOTS;
 
                status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size);
+               if (status != EFI_SUCCESS)
+                       return status;
        }
 
-       if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) && status == EFI_SUCCESS)
-               status = allocate_unaccepted_bitmap(nr_desc, map);
+       if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY))
+               return allocate_unaccepted_bitmap(nr_desc, map);
 
-       efi_bs_call(free_pool, map);
-       return status;
+       return EFI_SUCCESS;
 }
 
 struct exit_boot_struct {