diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0062-objtool-Detect-jumps-to-retpoline-thunks.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0062-objtool-Detect-jumps-to-retpoline-thunks.patch | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0062-objtool-Detect-jumps-to-retpoline-thunks.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0062-objtool-Detect-jumps-to-retpoline-thunks.patch new file mode 100644 index 00000000..6dc05533 --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.9.21/0062-objtool-Detect-jumps-to-retpoline-thunks.patch @@ -0,0 +1,64 @@ +From df3a283c0e5efdef9f4146188608fe8658478ec7 Mon Sep 17 00:00:00 2001 +From: Josh Poimboeuf <jpoimboe@redhat.com> +Date: Thu, 11 Jan 2018 21:46:23 +0000 +Subject: [PATCH 062/102] objtool: Detect jumps to retpoline thunks + +commit 39b735332cb8b33a27c28592d969e4016c86c3ea upstream. + +A direct jump to a retpoline thunk is really an indirect jump in +disguise. Change the objtool instruction type accordingly. + +Objtool needs to know where indirect branches are so it can detect +switch statement jump tables. + +This fixes a bunch of warnings with CONFIG_RETPOLINE like: + + arch/x86/events/intel/uncore_nhmex.o: warning: objtool: nhmex_rbox_msr_enable_event()+0x44: sibling call from callable instruction with modified stack frame + kernel/signal.o: warning: objtool: copy_siginfo_to_user()+0x91: sibling call from callable instruction with modified stack frame + ... + +Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> +Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> +Signed-off-by: Thomas Gleixner <tglx@linutronix.de> +Cc: gnomes@lxorguk.ukuu.org.uk +Cc: Rik van Riel <riel@redhat.com> +Cc: Andi Kleen <ak@linux.intel.com> +Cc: thomas.lendacky@amd.com +Cc: Peter Zijlstra <peterz@infradead.org> +Cc: Linus Torvalds <torvalds@linux-foundation.org> +Cc: Jiri Kosina <jikos@kernel.org> +Cc: Andy Lutomirski <luto@amacapital.net> +Cc: Dave Hansen <dave.hansen@intel.com> +Cc: Kees Cook <keescook@google.com> +Cc: Tim Chen <tim.c.chen@linux.intel.com> +Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> +Cc: Paul Turner <pjt@google.com> +Link: https://lkml.kernel.org/r/1515707194-20531-2-git-send-email-dwmw@amazon.co.uk +[dwmw2: Applies to tools/objtool/builtin-check.c not check.c] +Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + tools/objtool/builtin-check.c | 7 +++++++ + 1 file changed, 7 insertions(+) + +diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c +index 7b1f7b5..36784b8 100644 +--- a/tools/objtool/builtin-check.c ++++ b/tools/objtool/builtin-check.c +@@ -382,6 +382,13 @@ static int add_jump_destinations(struct objtool_file *file) + } else if (rela->sym->sec->idx) { + dest_sec = rela->sym->sec; + dest_off = rela->sym->sym.st_value + rela->addend + 4; ++ } else if (strstr(rela->sym->name, "_indirect_thunk_")) { ++ /* ++ * Retpoline jumps are really dynamic jumps in ++ * disguise, so convert them accordingly. ++ */ ++ insn->type = INSN_JUMP_DYNAMIC; ++ continue; + } else { + /* sibling call */ + insn->jump_dest = 0; +-- +2.7.4 + |