[PATCH 4.14 76/89] x86: Use __nostackprotect for sme_encrypt_kernel

From: Greg Kroah-Hartman
Date: Mon Jan 22 2018 - 03:53:44 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Laura Abbott <labbott@xxxxxxxxxx>

commit 91cfc88c66bf8ab95937606569670cf67fa73e09 upstream.

Commit bacf6b499e11 ("x86/mm: Use a struct to reduce parameters for SME
PGD mapping") moved some parameters into a structure.

The structure was large enough to trigger the stack protection canary in
sme_encrypt_kernel which doesn't work this early, causing reboots.

Mark sme_encrypt_kernel appropriately to not use the canary.

Fixes: bacf6b499e11 ("x86/mm: Use a struct to reduce parameters for SME PGD mapping")
Signed-off-by: Laura Abbott <labbott@xxxxxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
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
@@ -487,7 +487,7 @@ static unsigned long __init sme_pgtable_
return total;
}

-void __init sme_encrypt_kernel(struct boot_params *bp)
+void __init __nostackprotector sme_encrypt_kernel(struct boot_params *bp)
{
unsigned long workarea_start, workarea_end, workarea_len;
unsigned long execute_start, execute_end, execute_len;