This is a note to let you know that I've just added the patch titled
x86/ioremap: Fix page aligned size calculation in __ioremap_caller()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-ioremap-fix-page-aligned-size-calculation-in-__i.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e21129aeccfbe5a89d6f9e2ddc70a42f16f5e57c
Author: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Date: Sun Dec 4 13:52:01 2022 -0800
x86/ioremap: Fix page aligned size calculation in __ioremap_caller()
[ Upstream commit 4dbd6a3e90e03130973688fd79e19425f720d999 ]
Current code re-calculates the size after aligning the starting and
ending physical addresses on a page boundary. But the re-calculation
also embeds the masking of high order bits that exceed the size of
the physical address space (via PHYSICAL_PAGE_MASK). If the masking
removes any high order bits, the size calculation results in a huge
value that is likely to immediately fail.
Fix this by re-calculating the page-aligned size first. Then mask any
high order bits using PHYSICAL_PAGE_MASK.
Fixes: ffa71f33a820 ("x86, ioremap: Fix incorrect physical address handling in PAE mode")
Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Acked-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxx>
Link: https://lore.kernel.org/r/1668624097-14884-2-git-send-email-mikelley@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index ecae9ac216fa..696fd6fdc107 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -126,9 +126,15 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
* Mappings have to be page-aligned
*/
offset = phys_addr & ~PAGE_MASK;
- phys_addr &= PHYSICAL_PAGE_MASK;
+ phys_addr &= PAGE_MASK;
size = PAGE_ALIGN(last_addr+1) - phys_addr;
+ /*
+ * Mask out any bits not part of the actual physical
+ * address, like memory encryption bits.
+ */
+ phys_addr &= PHYSICAL_PAGE_MASK;
+
retval = reserve_memtype(phys_addr, (u64)phys_addr + size,
pcm, &new_pcm);
if (retval) {
