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-rw-r--r--scripts/kallsyms.c136
1 files changed, 105 insertions, 31 deletions
diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
index 3e8dea6e0a95..03fa07ad45d9 100644
--- a/scripts/kallsyms.c
+++ b/scripts/kallsyms.c
@@ -18,6 +18,7 @@
*
*/
+#include <getopt.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
@@ -27,14 +28,30 @@
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
-#define KSYM_NAME_LEN 128
+#define _stringify_1(x) #x
+#define _stringify(x) _stringify_1(x)
+
+#define KSYM_NAME_LEN 512
+
+/*
+ * A substantially bigger size than the current maximum.
+ *
+ * It cannot be defined as an expression because it gets stringified
+ * for the fscanf() format string. Therefore, a _Static_assert() is
+ * used instead to maintain the relationship with KSYM_NAME_LEN.
+ */
+#define KSYM_NAME_LEN_BUFFER 2048
+_Static_assert(
+ KSYM_NAME_LEN_BUFFER == KSYM_NAME_LEN * 4,
+ "Please keep KSYM_NAME_LEN_BUFFER in sync with KSYM_NAME_LEN"
+);
struct sym_entry {
unsigned long long addr;
unsigned int len;
unsigned int start_pos;
unsigned int percpu_absolute;
- unsigned char sym[0];
+ unsigned char sym[];
};
struct addr_range {
@@ -70,8 +87,8 @@ static unsigned char best_table_len[256];
static void usage(void)
{
- fprintf(stderr, "Usage: kallsyms [--all-symbols] "
- "[--base-relative] < in.map > out.S\n");
+ fprintf(stderr, "Usage: kallsyms [--all-symbols] [--absolute-percpu] "
+ "[--base-relative] in.map > out.S\n");
exit(1);
}
@@ -82,6 +99,7 @@ static char *sym_name(const struct sym_entry *s)
static bool is_ignored_symbol(const char *name, char type)
{
+ /* Symbol names that exactly match to the following are ignored.*/
static const char * const ignored_symbols[] = {
/*
* Symbols which vary between passes. Passes 1 and 2 must have
@@ -104,14 +122,22 @@ static bool is_ignored_symbol(const char *name, char type)
NULL
};
+ /* Symbol names that begin with the following are ignored.*/
static const char * const ignored_prefixes[] = {
- "$", /* local symbols for ARM, MIPS, etc. */
- ".LASANPC", /* s390 kasan local symbols */
- "__crc_", /* modversions */
"__efistub_", /* arm64 EFI stub namespace */
+ "__kvm_nvhe_$", /* arm64 local symbols in non-VHE KVM namespace */
+ "__kvm_nvhe_.L", /* arm64 local symbols in non-VHE KVM namespace */
+ "__AArch64ADRPThunk_", /* arm64 lld */
+ "__ARMV5PILongThunk_", /* arm lld */
+ "__ARMV7PILongThunk_",
+ "__ThumbV7PILongThunk_",
+ "__LA25Thunk_", /* mips lld */
+ "__microLA25Thunk_",
+ "__kcfi_typeid_", /* CFI type identifiers */
NULL
};
+ /* Symbol names that end with the following are ignored.*/
static const char * const ignored_suffixes[] = {
"_from_arm", /* arm */
"_from_thumb", /* arm */
@@ -119,9 +145,15 @@ static bool is_ignored_symbol(const char *name, char type)
NULL
};
+ /* Symbol names that contain the following are ignored.*/
+ static const char * const ignored_matches[] = {
+ ".long_branch.", /* ppc stub */
+ ".plt_branch.", /* ppc stub */
+ NULL
+ };
+
const char * const *p;
- /* Exclude symbols which vary between passes. */
for (p = ignored_symbols; *p; p++)
if (!strcmp(name, *p))
return true;
@@ -137,6 +169,11 @@ static bool is_ignored_symbol(const char *name, char type)
return true;
}
+ for (p = ignored_matches; *p; p++) {
+ if (strstr(name, *p))
+ return true;
+ }
+
if (type == 'U' || type == 'u')
return true;
/* exclude debugging symbols */
@@ -176,15 +213,15 @@ static void check_symbol_range(const char *sym, unsigned long long addr,
static struct sym_entry *read_symbol(FILE *in)
{
- char name[500], type;
+ char name[KSYM_NAME_LEN_BUFFER+1], type;
unsigned long long addr;
unsigned int len;
struct sym_entry *sym;
int rc;
- rc = fscanf(in, "%llx %c %499s\n", &addr, &type, name);
+ rc = fscanf(in, "%llx %c %" _stringify(KSYM_NAME_LEN_BUFFER) "s\n", &addr, &type, name);
if (rc != 3) {
- if (rc != EOF && fgets(name, 500, in) == NULL)
+ if (rc != EOF && fgets(name, ARRAY_SIZE(name), in) == NULL)
fprintf(stderr, "Read error or end of file.\n");
return NULL;
}
@@ -291,12 +328,19 @@ static void shrink_table(void)
}
}
-static void read_map(FILE *in)
+static void read_map(const char *in)
{
+ FILE *fp;
struct sym_entry *sym;
- while (!feof(in)) {
- sym = read_symbol(in);
+ fp = fopen(in, "r");
+ if (!fp) {
+ perror(in);
+ exit(1);
+ }
+
+ while (!feof(fp)) {
+ sym = read_symbol(fp);
if (!sym)
continue;
@@ -307,12 +351,15 @@ static void read_map(FILE *in)
table = realloc(table, sizeof(*table) * table_size);
if (!table) {
fprintf(stderr, "out of memory\n");
+ fclose(fp);
exit (1);
}
}
table[table_cnt++] = sym;
}
+
+ fclose(fp);
}
static void output_label(const char *label)
@@ -449,12 +496,35 @@ static void write_src(void)
if ((i & 0xFF) == 0)
markers[i >> 8] = off;
- printf("\t.byte 0x%02x", table[i]->len);
+ /* There cannot be any symbol of length zero. */
+ if (table[i]->len == 0) {
+ fprintf(stderr, "kallsyms failure: "
+ "unexpected zero symbol length\n");
+ exit(EXIT_FAILURE);
+ }
+
+ /* Only lengths that fit in up-to-two-byte ULEB128 are supported. */
+ if (table[i]->len > 0x3FFF) {
+ fprintf(stderr, "kallsyms failure: "
+ "unexpected huge symbol length\n");
+ exit(EXIT_FAILURE);
+ }
+
+ /* Encode length with ULEB128. */
+ if (table[i]->len <= 0x7F) {
+ /* Most symbols use a single byte for the length. */
+ printf("\t.byte 0x%02x", table[i]->len);
+ off += table[i]->len + 1;
+ } else {
+ /* "Big" symbols use two bytes. */
+ printf("\t.byte 0x%02x, 0x%02x",
+ (table[i]->len & 0x7F) | 0x80,
+ (table[i]->len >> 7) & 0x7F);
+ off += table[i]->len + 2;
+ }
for (k = 0; k < table[i]->len; k++)
printf(", 0x%02x", table[i]->sym[k]);
printf("\n");
-
- off += table[i]->len + 1;
}
printf("\n");
@@ -743,22 +813,26 @@ static void record_relative_base(void)
int main(int argc, char **argv)
{
- if (argc >= 2) {
- int i;
- for (i = 1; i < argc; i++) {
- if(strcmp(argv[i], "--all-symbols") == 0)
- all_symbols = 1;
- else if (strcmp(argv[i], "--absolute-percpu") == 0)
- absolute_percpu = 1;
- else if (strcmp(argv[i], "--base-relative") == 0)
- base_relative = 1;
- else
- usage();
- }
- } else if (argc != 1)
+ while (1) {
+ static struct option long_options[] = {
+ {"all-symbols", no_argument, &all_symbols, 1},
+ {"absolute-percpu", no_argument, &absolute_percpu, 1},
+ {"base-relative", no_argument, &base_relative, 1},
+ {},
+ };
+
+ int c = getopt_long(argc, argv, "", long_options, NULL);
+
+ if (c == -1)
+ break;
+ if (c != 0)
+ usage();
+ }
+
+ if (optind >= argc)
usage();
- read_map(stdin);
+ read_map(argv[optind]);
shrink_table();
if (absolute_percpu)
make_percpus_absolute();
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.