| From 1402fd8ed7e5bda1b3e7613b70780b0db392d1e6 Mon Sep 17 00:00:00 2001 |
| From: Josh Poimboeuf <jpoimboe@redhat.com> |
| Date: Wed, 28 Feb 2018 07:19:21 -0600 |
| Subject: objtool: Fix another switch table detection issue |
| |
| From: Josh Poimboeuf <jpoimboe@redhat.com> |
| |
| commit 1402fd8ed7e5bda1b3e7613b70780b0db392d1e6 upstream. |
| |
| Continue the switch table detection whack-a-mole. Add a check to |
| distinguish KASAN data reads from switch data reads. The switch jump |
| tables in .rodata have relocations associated with them. |
| |
| This fixes the following warning: |
| |
| crypto/asymmetric_keys/x509_cert_parser.o: warning: objtool: x509_note_pkey_algo()+0xa4: sibling call from callable instruction with modified stack frame |
| |
| Reported-by: Arnd Bergmann <arnd@arndb.de> |
| Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> |
| Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
| Tested-by: Arnd Bergmann <arnd@arndb.de> |
| Cc: Peter Zijlstra <peterz@infradead.org> |
| Link: https://lkml.kernel.org/r/d7c8853022ad47d158cb81e953a40469fc08a95e.1519784382.git.jpoimboe@redhat.com |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| tools/objtool/check.c | 6 +++++- |
| 1 file changed, 5 insertions(+), 1 deletion(-) |
| |
| --- a/tools/objtool/check.c |
| +++ b/tools/objtool/check.c |
| @@ -924,7 +924,11 @@ static struct rela *find_switch_table(st |
| if (find_symbol_containing(file->rodata, text_rela->addend)) |
| continue; |
| |
| - return find_rela_by_dest(file->rodata, text_rela->addend); |
| + rodata_rela = find_rela_by_dest(file->rodata, text_rela->addend); |
| + if (!rodata_rela) |
| + continue; |
| + |
| + return rodata_rela; |
| } |
| |
| return NULL; |
