module: Make .static_call_sites read-only after init

Section .static_call_sites holds data structures that need to be sorted and
processed only at module load time. This initial processing happens in
static_call_add_module(), which is invoked as a callback to the
MODULE_STATE_COMING notification from prepare_coming_module().

The section is never modified afterwards. Make it therefore read-only after
module initialization to avoid any (non-)accidental modifications.

Reviewed-by: Sami Tolvanen <[email protected]>
Reviewed-by: Luis Chamberlain <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Petr Pavlu <[email protected]>

Author: petrpavlu

kernel/module/strict_rwx.c

@@ -121,6 +121,15 @@ static const char *const ro_after_init[] = {
 	 * section, which are marked as such at module load time.
 	 */
 	"__jump_table",
+
+#ifdef CONFIG_HAVE_STATIC_CALL_INLINE
+	/*
+	 * Section .static_call_sites holds data structures that need to be
+	 * sorted and processed at module load time but are never modified
+	 * afterwards.
+	 */
+	".static_call_sites",
+#endif
 };
 
 void module_mark_ro_after_init(const Elf_Ehdr *hdr, Elf_Shdr *sechdrs,