Commit b2966952 authored Apr 01, 2020 by Josh Poimboeuf Committed by Borislav Petkov Apr 14, 2020

objtool: Make BP scratch register warning more robust



If func is NULL, a seg fault can result.

This is a theoretical issue which was found by Coverity, ID: 1492002
("Dereference after null check").

Fixes: c705cecc ("objtool: Track original function across branches")
Reported-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/afc628693a37acd287e843bcc5c0430263d93c74.1585761021.git.jpoimboe@redhat.com

parent b401efc1

tools/objtool/check.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -2005,8 +2005,8 @@ static int validate_return(struct symbol func, struct instruction insn, struct
		}

		if (state->bp_scratch) {
		WARN("%s uses BP as a scratch register",
		func->name);
		WARN_FUNC("BP used as a scratch register",
		insn->sec, insn->offset);
		return 1;
		}

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