[PATCH AUTOSEL 5.15 17/22] objtool: Fix SEGFAULT

[Sasha Levin]

From: Christophe Leroy <christophe.leroy@xxxxxxxxxx>

[ Upstream commit efb11fdb3e1a9f694fa12b70b21e69e55ec59c36 ]

find_insn() will return NULL in case of failure. Check insn in order
to avoid a kernel Oops for NULL pointer dereference.

Tested-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20221114175754.1131267-9-sv@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@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 72e5d23f1ad8..e27c73295c41 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -197,7 +197,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		return false;
 
 	insn = find_insn(file, func->sec, func->offset);
-	if (!insn->func)
+	if (!insn || !insn->func)
 		return false;
 
 	func_for_each_insn(file, func, insn) {
-- 
2.35.1