objtool: Return canonical symbol when aliases exist in symbol finding helpers

When symbol alias ambiguity exists in the symbol finding helper
functions, return the canonical sym->alias, as that's the one which gets
used by validate_branch() and elsewhere.

This doesn't fix any known issues, just makes the symbol alias behavior
more robust.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/450470a4897706af77453ad333e18af5ebab653c.1763671318.git.jpoimboe@kernel.org

diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index 4f15643ad70c81c52a168b3a4e432a266499898d..7e2c0ae6b41ac4acd9d9ce076b465e21023b1e83 100644 (file)
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -172,11 +172,11 @@ static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx)
 struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset)
 {
        struct rb_root_cached *tree = (struct rb_root_cached *)&sec->symbol_tree;
-       struct symbol *iter;
+       struct symbol *sym;
 
-       __sym_for_each(iter, tree, offset, offset) {
-               if (iter->offset == offset && !is_sec_sym(iter))
-                       return iter;
+       __sym_for_each(sym, tree, offset, offset) {
+               if (sym->offset == offset && !is_sec_sym(sym))
+                       return sym->alias;
        }
 
        return NULL;
@@ -185,11 +185,11 @@ struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset)
 struct symbol *find_func_by_offset(struct section *sec, unsigned long offset)
 {
        struct rb_root_cached *tree = (struct rb_root_cached *)&sec->symbol_tree;
-       struct symbol *iter;
+       struct symbol *func;
 
-       __sym_for_each(iter, tree, offset, offset) {
-               if (iter->offset == offset && is_func_sym(iter))
-                       return iter;
+       __sym_for_each(func, tree, offset, offset) {
+               if (func->offset == offset && is_func_sym(func))
+                       return func->alias;
        }
 
        return NULL;
@@ -220,7 +220,7 @@ struct symbol *find_symbol_containing(const struct section *sec, unsigned long o
                }
        }
 
-       return sym;
+       return sym ? sym->alias : NULL;
 }
 
 /*
@@ -266,11 +266,11 @@ int find_symbol_hole_containing(const struct section *sec, unsigned long offset)
 struct symbol *find_func_containing(struct section *sec, unsigned long offset)
 {
        struct rb_root_cached *tree = (struct rb_root_cached *)&sec->symbol_tree;
-       struct symbol *iter;
+       struct symbol *func;
 
-       __sym_for_each(iter, tree, offset, offset) {
-               if (is_func_sym(iter))
-                       return iter;
+       __sym_for_each(func, tree, offset, offset) {
+               if (is_func_sym(func))
+                       return func->alias;
        }
 
        return NULL;