[tip: objtool/core] objtool: Don't alias undefined symbols

["tip-bot2 for Josh Poimboeuf" <tip-bot2@linutronix.de>]

The following commit has been merged into the objtool/core branch of tip:

Commit-ID:     16f366c5a68839736d3616b466f1738811408ec7
Gitweb:        https://git.kernel.org/tip/16f366c5a68839736d3616b466f1738811408ec7
Author:        Josh Poimboeuf <jpoimboe@kernel.org>
AuthorDate:    Thu, 20 Nov 2025 12:52:17 -08:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Fri, 21 Nov 2025 10:04:08 +01:00

objtool: Don't alias undefined symbols

Objtool is mistakenly aliasing all undefined symbols.  That's obviously
wrong, though it has no consequence since objtool happens to only use
sym->alias for defined symbols.  Fix it regardless.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/bc401173a7717757eee672fc1ca5a20451d77b86.1763671318.git.jpoimboe@kernel.org
---
 tools/objtool/elf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index fffca31..4f15643 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -492,8 +492,8 @@ static int elf_add_symbol(struct elf *elf, struct symbol *sym)
 	sym->len = sym->sym.st_size;
 
 	__sym_for_each(iter, &sym->sec->symbol_tree, sym->offset, sym->offset) {
-		if (iter->offset == sym->offset && iter->type == sym->type &&
-		    iter->len == sym->len)
+		if (!is_undef_sym(iter) && iter->offset == sym->offset &&
+		    iter->type == sym->type && iter->len == sym->len)
 			iter->alias = sym;
 	}