From: Kees Cook <keescook@chromium.org> stable inclusion from stable-v5.10.134 commit c0a3a9eb262a5e86a36fd5fc4f9fc38470713f13 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5ZVR7 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 65cdf0d623bedf0e069bb64ed52e8bb20105e2ba upstream. Debugging missing return thunks is easier if we can see where they're happening. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/lkml/Ys66hwtFcGbYmoiZ@hirez.programming.kicks-ass.ne... Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Wei Li <liwei391@huawei.com> --- arch/x86/kernel/alternative.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index fa79a46fa5d2..9d3c0d70a555 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -709,7 +709,9 @@ void __init_or_module noinline apply_returns(s32 *start, s32 *end) dest = addr + insn.length + insn.immediate.value; if (__static_call_fixup(addr, op, dest) || - WARN_ON_ONCE(dest != &__x86_return_thunk)) + WARN_ONCE(dest != &__x86_return_thunk, + "missing return thunk: %pS-%pS: %*ph", + addr, dest, 5, addr)) continue; DPRINTK("return thunk at: %pS (%px) len: %d to: %pS", -- 2.20.1