6.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Helge Deller <deller@xxxxxx>
commit 213aa670153ed675a007c1f35c5db544b0fefc94 upstream.
Do not write-protect the kernel read-only and __ro_after_init sections
earlier than before mark_rodata_ro() is called. This fixes a boot issue on
parisc which is triggered by commit 91a1d97ef482 ("jump_label,module: Don't
alloc static_key_mod for __ro_after_init keys"). That commit may modify
static key contents in the __ro_after_init section at bootup, so this
section needs to be writable at least until mark_rodata_ro() is called.
Signed-off-by: Helge Deller <deller@xxxxxx>
Reported-by: matoro <matoro_mailinglist_kernel@xxxxxxxxx>
Reported-by: Christoph Biedl <linux-kernel.bfrz@xxxxxxxxxxxxxxxxxx>
Tested-by: Christoph Biedl <linux-kernel.bfrz@xxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/linux-parisc/096cad5aada514255cd7b0b9dbafc768@xxxxxxxxx/#r
Fixes: 91a1d97ef482 ("jump_label,module: Don't alloc static_key_mod for __ro_after_init keys")
Cc: stable@xxxxxxxxxxxxxxx # v6.10+
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/parisc/mm/init.c | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 34d91cb8b259..96970fa75e4a 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -459,7 +459,6 @@ void free_initmem(void)
unsigned long kernel_end = (unsigned long)&_end;
/* Remap kernel text and data, but do not touch init section yet. */
- kernel_set_to_readonly = true;
map_pages(init_end, __pa(init_end), kernel_end - init_end,
PAGE_KERNEL, 0);
@@ -493,11 +492,18 @@ void free_initmem(void)
#ifdef CONFIG_STRICT_KERNEL_RWX
void mark_rodata_ro(void)
{
- /* rodata memory was already mapped with KERNEL_RO access rights by
- pagetable_init() and map_pages(). No need to do additional stuff here */
- unsigned long roai_size = __end_ro_after_init - __start_ro_after_init;
+ unsigned long start = (unsigned long) &__start_rodata;
+ unsigned long end = (unsigned long) &__end_rodata;
- pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10);
+ pr_info("Write protecting the kernel read-only data: %luk\n",
+ (end - start) >> 10);
+
+ kernel_set_to_readonly = true;
+ map_pages(start, __pa(start), end - start, PAGE_KERNEL, 0);
+
+ /* force the kernel to see the new page table entries */
+ flush_cache_all();
+ flush_tlb_all();
}
#endif
--
2.46.0
