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parisc: Delay write-protection until mark_rodata_ro() call

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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 91a1d97ef4 ("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@gmx.de>
Reported-by: matoro <matoro_mailinglist_kernel@matoro.tk>
Reported-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Tested-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Link: https://lore.kernel.org/linux-parisc/096cad5aada514255cd7b0b9dbafc768@matoro.tk/#r
Fixes: 91a1d97ef4 ("jump_label,module: Don't alloc static_key_mod for __ro_after_init keys")
Cc: stable@vger.kernel.org # v6.10+
This commit is contained in:
Helge Deller 2024-08-31 14:02:06 +02:00
parent 5be63fc19f
commit 213aa67015
1 changed files with 11 additions and 5 deletions
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16
arch/parisc/mm/init.c
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@ -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