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-rw-r--r--include/linux/kallsyms.h11
-rw-r--r--kernel/kallsyms.c123
-rw-r--r--kernel/module.c3
3 files changed, 93 insertions, 44 deletions
diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
index 849043c..1cebcbc 100644
--- a/include/linux/kallsyms.h
+++ b/include/linux/kallsyms.h
@@ -12,6 +12,10 @@
/* Lookup the address for a symbol. Returns 0 if not found. */
unsigned long kallsyms_lookup_name(const char *name);
+extern int kallsyms_lookup_size_offset(unsigned long addr,
+ unsigned long *symbolsize,
+ unsigned long *offset);
+
/* Lookup an address. modname is set to NULL if it's in the kernel. */
const char *kallsyms_lookup(unsigned long addr,
unsigned long *symbolsize,
@@ -28,6 +32,13 @@ static inline unsigned long kallsyms_lookup_name(const char *name)
return 0;
}
+static inline int kallsyms_lookup_size_offset(unsigned long addr,
+ unsigned long *symbolsize,
+ unsigned long *offset)
+{
+ return 0;
+}
+
static inline const char *kallsyms_lookup(unsigned long addr,
unsigned long *symbolsize,
unsigned long *offset,
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 342bca6..eeac3e3 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -69,6 +69,15 @@ static inline int is_kernel(unsigned long addr)
return in_gate_area_no_task(addr);
}
+static int is_ksym_addr(unsigned long addr)
+{
+ if (all_var)
+ return is_kernel(addr);
+
+ return is_kernel_text(addr) || is_kernel_inittext(addr) ||
+ is_kernel_extratext(addr);
+}
+
/* expand a compressed symbol data into the resulting uncompressed string,
given the offset to where the symbol is in the compressed stream */
static unsigned int kallsyms_expand_symbol(unsigned int off, char *result)
@@ -155,6 +164,73 @@ unsigned long kallsyms_lookup_name(const char *name)
return module_kallsyms_lookup_name(name);
}
+static unsigned long get_symbol_pos(unsigned long addr,
+ unsigned long *symbolsize,
+ unsigned long *offset)
+{
+ unsigned long symbol_start = 0, symbol_end = 0;
+ unsigned long i, low, high, mid;
+
+ /* This kernel should never had been booted. */
+ BUG_ON(!kallsyms_addresses);
+
+ /* do a binary search on the sorted kallsyms_addresses array */
+ low = 0;
+ high = kallsyms_num_syms;
+
+ while (high - low > 1) {
+ mid = (low + high) / 2;
+ if (kallsyms_addresses[mid] <= addr)
+ low = mid;
+ else
+ high = mid;
+ }
+
+ /*
+ * search for the first aliased symbol. Aliased
+ * symbols are symbols with the same address
+ */
+ while (low && kallsyms_addresses[low-1] == kallsyms_addresses[low])
+ --low;
+
+ symbol_start = kallsyms_addresses[low];
+
+ /* Search for next non-aliased symbol */
+ for (i = low + 1; i < kallsyms_num_syms; i++) {
+ if (kallsyms_addresses[i] > symbol_start) {
+ symbol_end = kallsyms_addresses[i];
+ break;
+ }
+ }
+
+ /* if we found no next symbol, we use the end of the section */
+ if (!symbol_end) {
+ if (is_kernel_inittext(addr))
+ symbol_end = (unsigned long)_einittext;
+ else if (all_var)
+ symbol_end = (unsigned long)_end;
+ else
+ symbol_end = (unsigned long)_etext;
+ }
+
+ *symbolsize = symbol_end - symbol_start;
+ *offset = addr - symbol_start;
+
+ return low;
+}
+
+/*
+ * Lookup an address but don't bother to find any names.
+ */
+int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize,
+ unsigned long *offset)
+{
+ if (is_ksym_addr(addr))
+ return !!get_symbol_pos(addr, symbolsize, offset);
+
+ return !!module_address_lookup(addr, symbolsize, offset, NULL);
+}
+
/*
* Lookup an address
* - modname is set to NULL if it's in the kernel
@@ -167,57 +243,18 @@ const char *kallsyms_lookup(unsigned long addr,
unsigned long *offset,
char **modname, char *namebuf)
{
- unsigned long i, low, high, mid;
const char *msym;
- /* This kernel should never had been booted. */
- BUG_ON(!kallsyms_addresses);
-
namebuf[KSYM_NAME_LEN] = 0;
namebuf[0] = 0;
- if ((all_var && is_kernel(addr)) ||
- (!all_var && (is_kernel_text(addr) || is_kernel_inittext(addr) ||
- is_kernel_extratext(addr)))) {
- unsigned long symbol_end = 0;
-
- /* do a binary search on the sorted kallsyms_addresses array */
- low = 0;
- high = kallsyms_num_syms;
-
- while (high-low > 1) {
- mid = (low + high) / 2;
- if (kallsyms_addresses[mid] <= addr) low = mid;
- else high = mid;
- }
-
- /* search for the first aliased symbol. Aliased symbols are
- symbols with the same address */
- while (low && kallsyms_addresses[low - 1] == kallsyms_addresses[low])
- --low;
+ if (is_ksym_addr(addr)) {
+ unsigned long pos;
+ pos = get_symbol_pos(addr, symbolsize, offset);
/* Grab name */
- kallsyms_expand_symbol(get_symbol_offset(low), namebuf);
-
- /* Search for next non-aliased symbol */
- for (i = low + 1; i < kallsyms_num_syms; i++) {
- if (kallsyms_addresses[i] > kallsyms_addresses[low]) {
- symbol_end = kallsyms_addresses[i];
- break;
- }
- }
-
- /* if we found no next symbol, we use the end of the section */
- if (!symbol_end) {
- if (is_kernel_inittext(addr))
- symbol_end = (unsigned long)_einittext;
- else
- symbol_end = all_var ? (unsigned long)_end : (unsigned long)_etext;
- }
-
- *symbolsize = symbol_end - kallsyms_addresses[low];
+ kallsyms_expand_symbol(get_symbol_offset(pos), namebuf);
*modname = NULL;
- *offset = addr - kallsyms_addresses[low];
return namebuf;
}
diff --git a/kernel/module.c b/kernel/module.c
index 7c77a0a..7f60e78 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2040,7 +2040,8 @@ const char *module_address_lookup(unsigned long addr,
list_for_each_entry(mod, &modules, list) {
if (within(addr, mod->module_init, mod->init_size)
|| within(addr, mod->module_core, mod->core_size)) {
- *modname = mod->name;
+ if (modname)
+ *modname = mod->name;
return get_ksymbol(mod, addr, size, offset);
}
}
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