[tip: objtool/core] objtool: is_fentry_call() crashes if call has no destination

[tip-bot2 for Alexandre Chartre]

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

Commit-ID:     87cf61fe848ca8ddf091548671e168f52e8a718e
Gitweb:        https://git.kernel.org/tip/87cf61fe848ca8ddf091548671e168f52e8a718e
Author:        Alexandre Chartre <alexandre.chartre@xxxxxxxxxx>
AuthorDate:    Tue, 14 Apr 2020 12:36:10 +02:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Thu, 30 Apr 2020 20:14:32 +02:00

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@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Miroslav Benes <mbenes@xxxxxxx>
Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Link: https://lkml.kernel.org/r/20200414103618.12657-2-alexandre.chartre@xxxxxxxxxx
---
 tools/objtool/check.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index fa9bf36..8af8de2 100644
--- 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;