1 files changed, 49 insertions, 12 deletions

diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index fafd1a3ef0da..6a3b249a2ae1 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -23,6 +23,7 @@
 #include <linux/mm.h>
 #include <linux/ctype.h>
 #include <linux/slab.h>
+#include <linux/filter.h>
 #include <linux/compiler.h>
 
 #include <asm/sections.h>
@@ -300,10 +301,11 @@ int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize,
                                 unsigned long *offset)
 {
         char namebuf[KSYM_NAME_LEN];
+
         if (is_ksym_addr(addr))
                 return !!get_symbol_pos(addr, symbolsize, offset);
-
-        return !!module_address_lookup(addr, symbolsize, offset, NULL, namebuf);
+        return !!module_address_lookup(addr, symbolsize, offset, NULL, namebuf) ||
+               !!__bpf_address_lookup(addr, symbolsize, offset, namebuf);
 }
 
 /*
@@ -318,6 +320,8 @@ const char *kallsyms_lookup(unsigned long addr,
                             unsigned long *offset,
                             char **modname, char *namebuf)
 {
+        const char *ret;
+
         namebuf[KSYM_NAME_LEN - 1] = 0;
         namebuf[0] = 0;
 
@@ -333,9 +337,13 @@ const char *kallsyms_lookup(unsigned long addr,
                 return namebuf;
         }
 
-        /* See if it's in a module. */
-        return module_address_lookup(addr, symbolsize, offset, modname,
-                                     namebuf);
+        /* See if it's in a module or a BPF JITed image. */
+        ret = module_address_lookup(addr, symbolsize, offset,
+                                    modname, namebuf);
+        if (!ret)
+                ret = bpf_address_lookup(addr, symbolsize,
+                                         offset, modname, namebuf);
+        return ret;
 }
 
 int lookup_symbol_name(unsigned long addr, char *symname)
@@ -471,6 +479,7 @@ EXPORT_SYMBOL(__print_symbol);
 /* To avoid using get_symbol_offset for every symbol, we carry prefix along. */
 struct kallsym_iter {
         loff_t pos;
+        loff_t pos_mod_end;
         unsigned long value;
         unsigned int nameoff; /* If iterating in core kernel symbols. */
         char type;
@@ -481,13 +490,27 @@ struct kallsym_iter {
 
 static int get_ksymbol_mod(struct kallsym_iter *iter)
 {
-        if (module_get_kallsym(iter->pos - kallsyms_num_syms, &iter->value,
-                                &iter->type, iter->name, iter->module_name,
-                                &iter->exported) < 0)
+        int ret = module_get_kallsym(iter->pos - kallsyms_num_syms,
+                                     &iter->value, &iter->type,
+                                     iter->name, iter->module_name,
+                                     &iter->exported);
+        if (ret < 0) {
+                iter->pos_mod_end = iter->pos;
                 return 0;
+        }
+
         return 1;
 }
 
+static int get_ksymbol_bpf(struct kallsym_iter *iter)
+{
+        iter->module_name[0] = '\0';
+        iter->exported = 0;
+        return bpf_get_kallsym(iter->pos - iter->pos_mod_end,
+                               &iter->value, &iter->type,
+                               iter->name) < 0 ? 0 : 1;
+}
+
 /* Returns space to next name. */
 static unsigned long get_ksymbol_core(struct kallsym_iter *iter)
 {
@@ -508,16 +531,30 @@ static void reset_iter(struct kallsym_iter *iter, loff_t new_pos)
         iter->name[0] = '\0';
         iter->nameoff = get_symbol_offset(new_pos);
         iter->pos = new_pos;
+        if (new_pos == 0)
+                iter->pos_mod_end = 0;
+}
+
+static int update_iter_mod(struct kallsym_iter *iter, loff_t pos)
+{
+        iter->pos = pos;
+
+        if (iter->pos_mod_end > 0 &&
+            iter->pos_mod_end < iter->pos)
+                return get_ksymbol_bpf(iter);
+
+        if (!get_ksymbol_mod(iter))
+                return get_ksymbol_bpf(iter);
+
+        return 1;
 }
 
 /* Returns false if pos at or past end of file. */
 static int update_iter(struct kallsym_iter *iter, loff_t pos)
 {
         /* Module symbols can be accessed randomly. */
-        if (pos >= kallsyms_num_syms) {
-                iter->pos = pos;
-                return get_ksymbol_mod(iter);
-        }
+        if (pos >= kallsyms_num_syms)
+                return update_iter_mod(iter, pos);
 
         /* If we're not on the desired position, reset to new position. */
         if (pos != iter->pos)