objtool: is_fentry_call() crashes if call has no destination

Fix is_fentry_call() so that it works if a call has no destination
set (call_dest). This needs to be done in order to support intra-
function calls.

Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200414103618.12657-2-alexandre.chartre@oracle.com

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index fa9bf36..8af8de2 100644 (file)
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1484,7 +1484,7 @@ static int decode_sections(struct objtool_file *file)
 
 static bool is_fentry_call(struct instruction *insn)
 {
-       if (insn->type == INSN_CALL &&
+       if (insn->type == INSN_CALL && insn->call_dest &&
            insn->call_dest->type == STT_NOTYPE &&
            !strcmp(insn->call_dest->name, "__fentry__"))
                return true;