[PATCH v2 2/6] x86/alternative: Rename apply_ibt_endbr()

From: Peter Zijlstra
Date: Thu Jun 22 2023 - 10:50:52 EST


The current name doesn't reflect what it does very well.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/um/kernel/um_arch.c | 2 +-
arch/x86/include/asm/alternative.h | 2 +-
arch/x86/include/asm/ibt.h | 2 +-
arch/x86/kernel/alternative.c | 9 ++++++---
arch/x86/kernel/module.c | 2 +-
5 files changed, 10 insertions(+), 7 deletions(-)

--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -437,7 +437,7 @@ void __init arch_cpu_finalize_init(void)
os_check_bugs();
}

-void apply_ibt_endbr(s32 *start, s32 *end)
+void apply_seal_endbr(s32 *start, s32 *end)
{
}

--- a/arch/x86/include/asm/alternative.h
+++ b/arch/x86/include/asm/alternative.h
@@ -96,7 +96,7 @@ extern void alternative_instructions(voi
extern void apply_alternatives(struct alt_instr *start, struct alt_instr *end);
extern void apply_retpolines(s32 *start, s32 *end);
extern void apply_returns(s32 *start, s32 *end);
-extern void apply_ibt_endbr(s32 *start, s32 *end);
+extern void apply_seal_endbr(s32 *start, s32 *end);
extern void apply_fineibt(s32 *start_retpoline, s32 *end_retpoine,
s32 *start_cfi, s32 *end_cfi);

--- a/arch/x86/include/asm/ibt.h
+++ b/arch/x86/include/asm/ibt.h
@@ -34,7 +34,7 @@
/*
* Create a dummy function pointer reference to prevent objtool from marking
* the function as needing to be "sealed" (i.e. ENDBR converted to NOP by
- * apply_ibt_endbr()).
+ * apply_seal_endbr()).
*/
#define IBT_NOSEAL(fname) \
".pushsection .discard.ibt_endbr_noseal\n\t" \
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -803,7 +803,7 @@ static void __init_or_module poison_endb
/*
* Generated by: objtool --ibt
*/
-void __init_or_module noinline apply_ibt_endbr(s32 *start, s32 *end)
+void __init_or_module noinline apply_seal_endbr(s32 *start, s32 *end)
{
s32 *s;

@@ -818,7 +818,7 @@ void __init_or_module noinline apply_ibt

#else

-void __init_or_module apply_ibt_endbr(s32 *start, s32 *end) { }
+void __init_or_module apply_seal_endbr(s32 *start, s32 *end) { }

#endif /* CONFIG_X86_KERNEL_IBT */

@@ -1565,7 +1565,10 @@ void __init alternative_instructions(voi
*/
callthunks_patch_builtin_calls();

- apply_ibt_endbr(__ibt_endbr_seal, __ibt_endbr_seal_end);
+ /*
+ * Seal all functions that do not have their address taken.
+ */
+ apply_seal_endbr(__ibt_endbr_seal, __ibt_endbr_seal_end);

#ifdef CONFIG_SMP
/* Patch to UP if other cpus not imminent. */
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -358,7 +358,7 @@ int module_finalize(const Elf_Ehdr *hdr,
}
if (ibt_endbr) {
void *iseg = (void *)ibt_endbr->sh_addr;
- apply_ibt_endbr(iseg, iseg + ibt_endbr->sh_size);
+ apply_seal_endbr(iseg, iseg + ibt_endbr->sh_size);
}
if (locks) {
void *lseg = (void *)locks->sh_addr;