This is a note to let you know that I've just added the patch titled x86/mem_encrypt: Correct physical address calculation in __set_clr_pte_enc() to the 5.4-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-mem_encrypt-correct-physical-address-calculation-in-__set_clr_pte_enc.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 8249d17d3194eac064a8ca5bc5ca0abc86feecde Mon Sep 17 00:00:00 2001 From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx> Date: Thu, 18 Mar 2021 13:26:57 -0700 Subject: x86/mem_encrypt: Correct physical address calculation in __set_clr_pte_enc() From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx> commit 8249d17d3194eac064a8ca5bc5ca0abc86feecde upstream. The pfn variable contains the page frame number as returned by the pXX_pfn() functions, shifted to the right by PAGE_SHIFT to remove the page bits. After page protection computations are done to it, it gets shifted back to the physical address using page_level_shift(). That is wrong, of course, because that function determines the shift length based on the level of the page in the page table but in all the cases, it was shifted by PAGE_SHIFT before. Therefore, shift it back using PAGE_SHIFT to get the correct physical address. [ bp: Rewrite commit message. ] Fixes: dfaaec9033b8 ("x86: Add support for changing memory encryption attribute in early boot") Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/81abbae1657053eccc535c16151f63cd049dcb97.1616098294.git.isaku.yamahata@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/mm/mem_encrypt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -229,7 +229,7 @@ static void __init __set_clr_pte_enc(pte if (pgprot_val(old_prot) == pgprot_val(new_prot)) return; - pa = pfn << page_level_shift(level); + pa = pfn << PAGE_SHIFT; size = page_level_size(level); /* Patches currently in stable-queue which might be from isaku.yamahata@xxxxxxxxx are queue-5.4/x86-mem_encrypt-correct-physical-address-calculation-in-__set_clr_pte_enc.patch