Commit bcb1b6ff authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

objtool: Correctly handle retpoline thunk calls 



Just like JMP handling, convert a direct CALL to a retpoline thunk
into a retpoline safe indirect CALL.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Reviewed-by: default avatarMiroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/20210326151259.567568238@infradead.org
parent 11925185

tools/objtool/check.c

+12 −0
Original line number Diff line number Diff line
@@ -1025,6 +1025,18 @@ static int add_call_destinations(struct objtool_file *file) 
					  dest_off);

				return -1;

			}



		} else if (!strncmp(reloc->sym->name, "__x86_indirect_thunk_", 21)) {

			/*

			 * Retpoline calls are really dynamic calls in

			 * disguise, so convert them accordingly.

			 */

			insn->type = INSN_CALL_DYNAMIC;

			insn->retpoline_safe = true;



			remove_insn_ops(insn);

			continue;



		} else

			insn->call_dest = reloc->sym;