|
@@ -686,6 +686,30 @@ static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf_Addr addr,
|
|
|
return NULL;
|
|
|
}
|
|
|
|
|
|
+static inline int is_arm_mapping_symbol(const char *str)
|
|
|
+{
|
|
|
+ return str[0] == '$' && strchr("atd", str[1])
|
|
|
+ && (str[2] == '\0' || str[2] == '.');
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+ * If there's no name there, ignore it; likewise, ignore it if it's
|
|
|
+ * one of the magic symbols emitted used by current ARM tools.
|
|
|
+ *
|
|
|
+ * Otherwise if find_symbols_between() returns those symbols, they'll
|
|
|
+ * fail the whitelist tests and cause lots of false alarms ... fixable
|
|
|
+ * only by merging __exit and __init sections into __text, bloating
|
|
|
+ * the kernel (which is especially evil on embedded platforms).
|
|
|
+ */
|
|
|
+static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
|
|
|
+{
|
|
|
+ const char *name = elf->strtab + sym->st_name;
|
|
|
+
|
|
|
+ if (!name || !strlen(name))
|
|
|
+ return 0;
|
|
|
+ return !is_arm_mapping_symbol(name);
|
|
|
+}
|
|
|
+
|
|
|
/*
|
|
|
* Find symbols before or equal addr and after addr - in the section sec.
|
|
|
* If we find two symbols with equal offset prefer one with a valid name.
|
|
@@ -714,16 +738,15 @@ static void find_symbols_between(struct elf_info *elf, Elf_Addr addr,
|
|
|
symsec = secstrings + elf->sechdrs[sym->st_shndx].sh_name;
|
|
|
if (strcmp(symsec, sec) != 0)
|
|
|
continue;
|
|
|
+ if (!is_valid_name(elf, sym))
|
|
|
+ continue;
|
|
|
if (sym->st_value <= addr) {
|
|
|
if ((addr - sym->st_value) < beforediff) {
|
|
|
beforediff = addr - sym->st_value;
|
|
|
*before = sym;
|
|
|
}
|
|
|
else if ((addr - sym->st_value) == beforediff) {
|
|
|
- /* equal offset, valid name? */
|
|
|
- const char *name = elf->strtab + sym->st_name;
|
|
|
- if (name && strlen(name))
|
|
|
- *before = sym;
|
|
|
+ *before = sym;
|
|
|
}
|
|
|
}
|
|
|
else
|
|
@@ -733,10 +756,7 @@ static void find_symbols_between(struct elf_info *elf, Elf_Addr addr,
|
|
|
*after = sym;
|
|
|
}
|
|
|
else if ((sym->st_value - addr) == afterdiff) {
|
|
|
- /* equal offset, valid name? */
|
|
|
- const char *name = elf->strtab + sym->st_name;
|
|
|
- if (name && strlen(name))
|
|
|
- *after = sym;
|
|
|
+ *after = sym;
|
|
|
}
|
|
|
}
|
|
|
}
|