History

Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi into efi/core

More EFI updates for v5.7 - Incorporate a stable branch with the EFI pieces of Hans's work on loading device firmware from EFI boot service memory regions

Ingo Molnar committed 6 years ago

Commit 3be5f0d2 parents c98a76e f0df68d8 files · +264 −0Browse files

Unified · Split

8 files
  1. arch/x86/platform/efi/efi.c +2 −0
  2. arch/x86/platform/efi/quirks.c +4 −0
  3. drivers/firmware/efi/Kconfig +5 −0
  4. drivers/firmware/efi/Makefile +1 −0
  5. drivers/firmware/efi/efi.c +57 −0
  6. drivers/firmware/efi/embedded-firmware.c +147 −0
  7. include/linux/efi.h +7 −0
  8. include/linux/efi_embedded_fw.h +41 −0
arch/x86/platform/efi/efi.c+2−0
@@ -246,6 +246,7 @@ int __init efi_memblock_x86_reserve_range(void) · 245 unmodified lines
246 efi.memmap.desc_version);246 efi.memmap.desc_version);
247 247
248 memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size);248 memblock_reserve(pmap, efi.memmap.nr_map * efi.memmap.desc_size);
249 set_bit(EFI_PRESERVE_BS_REGIONS, &efi.flags);
249 250
250 return 0;251 return 0;
251}252}
@@ -901,6 +902,7 @@ static void __init __efi_enter_virtual_mode(void) · 649 unmodified lines
901 goto err;902 goto err;
902 }903 }
903 904
905 efi_check_for_embedded_firmwares();
904 efi_free_boot_services();906 efi_free_boot_services();
905 907
906 if (!efi_is_mixed())908 if (!efi_is_mixed())
arch/x86/platform/efi/quirks.c+4−0
@@ -410,6 +410,10 @@ void __init efi_free_boot_services(void) · 409 unmodified lines
410 int num_entries = 0;410 int num_entries = 0;
411 void *new, *new_md;411 void *new, *new_md;
412 412
413 /* Keep all regions for /sys/kernel/debug/efi */
414 if (efi_enabled(EFI_DBG))
415 return;
416
413 for_each_efi_memory_desc(md) {417 for_each_efi_memory_desc(md) {
414 unsigned long long start = md->phys_addr;418 unsigned long long start = md->phys_addr;
415 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;419 unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
drivers/firmware/efi/Kconfig+5−0
@@ -239,6 +239,11 @@ config EFI_DISABLE_PCI_DMA · 238 unmodified lines
239 239
240endmenu240endmenu
241 241
242config EFI_EMBEDDED_FIRMWARE
243 bool
244 depends on EFI
245 select CRYPTO_LIB_SHA256
246
242config UEFI_CPER247config UEFI_CPER
243 bool248 bool
244 249
drivers/firmware/efi/Makefile+1−0
@@ -27,6 +27,7 @@ obj-$(CONFIG_EFI_TEST) += test/ · 26 unmodified lines
27obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o27obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o
28obj-$(CONFIG_APPLE_PROPERTIES) += apple-properties.o28obj-$(CONFIG_APPLE_PROPERTIES) += apple-properties.o
29obj-$(CONFIG_EFI_RCI2_TABLE) += rci2-table.o29obj-$(CONFIG_EFI_RCI2_TABLE) += rci2-table.o
30obj-$(CONFIG_EFI_EMBEDDED_FIRMWARE) += embedded-firmware.o
30 31
31fake_map-y += fake_mem.o32fake_map-y += fake_mem.o
32fake_map-$(CONFIG_X86) += x86_fake_mem.o33fake_map-$(CONFIG_X86) += x86_fake_mem.o
drivers/firmware/efi/efi.c+57−0
@@ -17,6 +17,7 @@ · 16 unmodified lines
17#include <linux/kobject.h>17#include <linux/kobject.h>
18#include <linux/module.h>18#include <linux/module.h>
19#include <linux/init.h>19#include <linux/init.h>
20#include <linux/debugfs.h>
20#include <linux/device.h>21#include <linux/device.h>
21#include <linux/efi.h>22#include <linux/efi.h>
22#include <linux/of.h>23#include <linux/of.h>
@@ -291,6 +292,59 @@ free_entry: · 268 unmodified lines
291static inline int efivar_ssdt_load(void) { return 0; }292static inline int efivar_ssdt_load(void) { return 0; }
292#endif293#endif
293 294
295#ifdef CONFIG_DEBUG_FS
296
297#define EFI_DEBUGFS_MAX_BLOBS 32
298
299static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS];
300
301static void __init efi_debugfs_init(void)
302{
303 struct dentry *efi_debugfs;
304 efi_memory_desc_t *md;
305 char name[32];
306 int type_count[EFI_BOOT_SERVICES_DATA + 1] = {};
307 int i = 0;
308
309 efi_debugfs = debugfs_create_dir("efi", NULL);
310 if (IS_ERR_OR_NULL(efi_debugfs))
311 return;
312
313 for_each_efi_memory_desc(md) {
314 switch (md->type) {
315 case EFI_BOOT_SERVICES_CODE:
316 snprintf(name, sizeof(name), "boot_services_code%d",
317 type_count[md->type]++);
318 break;
319 case EFI_BOOT_SERVICES_DATA:
320 snprintf(name, sizeof(name), "boot_services_data%d",
321 type_count[md->type]++);
322 break;
323 default:
324 continue;
325 }
326
327 if (i >= EFI_DEBUGFS_MAX_BLOBS) {
328 pr_warn("More then %d EFI boot service segments, only showing first %d in debugfs\n",
329 EFI_DEBUGFS_MAX_BLOBS, EFI_DEBUGFS_MAX_BLOBS);
330 break;
331 }
332
333 debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT;
334 debugfs_blob[i].data = memremap(md->phys_addr,
335 debugfs_blob[i].size,
336 MEMREMAP_WB);
337 if (!debugfs_blob[i].data)
338 continue;
339
340 debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]);
341 i++;
342 }
343}
344#else
345static inline void efi_debugfs_init(void) {}
346#endif
347
294/*348/*
295 * We register the efi subsystem with the firmware subsystem and the349 * We register the efi subsystem with the firmware subsystem and the
296 * efivars subsystem with the efi subsystem, if the system was booted with350 * efivars subsystem with the efi subsystem, if the system was booted with
@@ -357,6 +411,9 @@ static int __init efisubsys_init(void) · 60 unmodified lines
357 goto err_remove_group;411 goto err_remove_group;
358 }412 }
359 413
414 if (efi_enabled(EFI_DBG) && efi_enabled(EFI_PRESERVE_BS_REGIONS))
415 efi_debugfs_init();
416
360 return 0;417 return 0;
361 418
362err_remove_group:419err_remove_group:
drivers/firmware/efi/embedded-firmware.c+147−0
@@ -0,0 +1,147 @@
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Support for extracting embedded firmware for peripherals from EFI code,
4 *
5 * Copyright (c) 2018 Hans de Goede <hdegoede@redhat.com>
6 */
7
8#include <linux/dmi.h>
9#include <linux/efi.h>
10#include <linux/efi_embedded_fw.h>
11#include <linux/io.h>
12#include <linux/slab.h>
13#include <linux/types.h>
14#include <linux/vmalloc.h>
15#include <crypto/sha.h>
16
17/* Exported for use by lib/test_firmware.c only */
18LIST_HEAD(efi_embedded_fw_list);
19EXPORT_SYMBOL_GPL(efi_embedded_fw_list);
20
21static bool checked_for_fw;
22
23static const struct dmi_system_id * const embedded_fw_table[] = {
24 NULL
25};
26
27/*
28 * Note the efi_check_for_embedded_firmwares() code currently makes the
29 * following 2 assumptions. This may needs to be revisited if embedded firmware
30 * is found where this is not true:
31 * 1) The firmware is only found in EFI_BOOT_SERVICES_CODE memory segments
32 * 2) The firmware always starts at an offset which is a multiple of 8 bytes
33 */
34static int __init efi_check_md_for_embedded_firmware(
35 efi_memory_desc_t *md, const struct efi_embedded_fw_desc *desc)
36{
37 struct sha256_state sctx;
38 struct efi_embedded_fw *fw;
39 u8 sha256[32];
40 u64 i, size;
41 u8 *map;
42
43 size = md->num_pages << EFI_PAGE_SHIFT;
44 map = memremap(md->phys_addr, size, MEMREMAP_WB);
45 if (!map) {
46 pr_err("Error mapping EFI mem at %#llx\n", md->phys_addr);
47 return -ENOMEM;
48 }
49
50 for (i = 0; (i + desc->length) <= size; i += 8) {
51 if (memcmp(map + i, desc->prefix, EFI_EMBEDDED_FW_PREFIX_LEN))
52 continue;
53
54 sha256_init(&sctx);
55 sha256_update(&sctx, map + i, desc->length);
56 sha256_final(&sctx, sha256);
57 if (memcmp(sha256, desc->sha256, 32) == 0)
58 break;
59 }
60 if ((i + desc->length) > size) {
61 memunmap(map);
62 return -ENOENT;
63 }
64
65 pr_info("Found EFI embedded fw '%s'\n", desc->name);
66
67 fw = kmalloc(sizeof(*fw), GFP_KERNEL);
68 if (!fw) {
69 memunmap(map);
70 return -ENOMEM;
71 }
72
73 fw->data = kmemdup(map + i, desc->length, GFP_KERNEL);
74 memunmap(map);
75 if (!fw->data) {
76 kfree(fw);
77 return -ENOMEM;
78 }
79
80 fw->name = desc->name;
81 fw->length = desc->length;
82 list_add(&fw->list, &efi_embedded_fw_list);
83
84 return 0;
85}
86
87void __init efi_check_for_embedded_firmwares(void)
88{
89 const struct efi_embedded_fw_desc *fw_desc;
90 const struct dmi_system_id *dmi_id;
91 efi_memory_desc_t *md;
92 int i, r;
93
94 for (i = 0; embedded_fw_table[i]; i++) {
95 dmi_id = dmi_first_match(embedded_fw_table[i]);
96 if (!dmi_id)
97 continue;
98
99 fw_desc = dmi_id->driver_data;
100
101 /*
102 * In some drivers the struct driver_data contains may contain
103 * other driver specific data after the fw_desc struct; and
104 * the fw_desc struct itself may be empty, skip these.
105 */
106 if (!fw_desc->name)
107 continue;
108
109 for_each_efi_memory_desc(md) {
110 if (md->type != EFI_BOOT_SERVICES_CODE)
111 continue;
112
113 r = efi_check_md_for_embedded_firmware(md, fw_desc);
114 if (r == 0)
115 break;
116 }
117 }
118
119 checked_for_fw = true;
120}
121
122int efi_get_embedded_fw(const char *name, const u8 **data, size_t *size)
123{
124 struct efi_embedded_fw *iter, *fw = NULL;
125
126 if (!checked_for_fw) {
127 pr_warn("Warning %s called while we did not check for embedded fw\n",
128 __func__);
129 return -ENOENT;
130 }
131
132 list_for_each_entry(iter, &efi_embedded_fw_list, list) {
133 if (strcmp(name, iter->name) == 0) {
134 fw = iter;
135 break;
136 }
137 }
138
139 if (!fw)
140 return -ENOENT;
141
142 *data = fw->data;
143 *size = fw->length;
144
145 return 0;
146}
147EXPORT_SYMBOL_GPL(efi_get_embedded_fw);
include/linux/efi.h+7−0
@@ -775,6 +775,7 @@ extern int __init efi_setup_pcdp_console(char *); · 774 unmodified lines
775#define EFI_NX_PE_DATA 9 /* Can runtime data regions be mapped non-executable? */775#define EFI_NX_PE_DATA 9 /* Can runtime data regions be mapped non-executable? */
776#define EFI_MEM_ATTR 10 /* Did firmware publish an EFI_MEMORY_ATTRIBUTES table? */776#define EFI_MEM_ATTR 10 /* Did firmware publish an EFI_MEMORY_ATTRIBUTES table? */
777#define EFI_MEM_NO_SOFT_RESERVE 11 /* Is the kernel configured to ignore soft reservations? */777#define EFI_MEM_NO_SOFT_RESERVE 11 /* Is the kernel configured to ignore soft reservations? */
778#define EFI_PRESERVE_BS_REGIONS 12 /* Are EFI boot-services memory segments available? */
778 779
779#ifdef CONFIG_EFI780#ifdef CONFIG_EFI
780/*781/*
@@ -1097,6 +1098,12 @@ static inline void · 316 unmodified lines
1097efi_enable_reset_attack_mitigation(void) { }1098efi_enable_reset_attack_mitigation(void) { }
1098#endif1099#endif
1099 1100
1101#ifdef CONFIG_EFI_EMBEDDED_FIRMWARE
1102void efi_check_for_embedded_firmwares(void);
1103#else
1104static inline void efi_check_for_embedded_firmwares(void) { }
1105#endif
1106
1100efi_status_t efi_random_get_seed(void);1107efi_status_t efi_random_get_seed(void);
1101 1108
1102void efi_retrieve_tpm2_eventlog(void);1109void efi_retrieve_tpm2_eventlog(void);
include/linux/efi_embedded_fw.h+41−0
@@ -0,0 +1,41 @@
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_EFI_EMBEDDED_FW_H
3#define _LINUX_EFI_EMBEDDED_FW_H
4
5#include <linux/list.h>
6#include <linux/mod_devicetable.h>
7
8#define EFI_EMBEDDED_FW_PREFIX_LEN 8
9
10/*
11 * This struct and efi_embedded_fw_list are private to the efi-embedded fw
12 * implementation they are in this header for use by lib/test_firmware.c only!
13 */
14struct efi_embedded_fw {
15 struct list_head list;
16 const char *name;
17 const u8 *data;
18 size_t length;
19};
20
21extern struct list_head efi_embedded_fw_list;
22
23/**
24 * struct efi_embedded_fw_desc - This struct is used by the EFI embedded-fw
25 * code to search for embedded firmwares.
26 *
27 * @name: Name to register the firmware with if found
28 * @prefix: First 8 bytes of the firmware
29 * @length: Length of the firmware in bytes including prefix
30 * @sha256: SHA256 of the firmware
31 */
32struct efi_embedded_fw_desc {
33 const char *name;
34 u8 prefix[EFI_EMBEDDED_FW_PREFIX_LEN];
35 u32 length;
36 u8 sha256[32];
37};
38
39int efi_get_embedded_fw(const char *name, const u8 **dat, size_t *sz);
40
41#endif