[PATCH 4.19 41/50] Xen/x86: also check kernel mapping in set_foreign_p2m_mapping()
From: Greg Kroah-Hartman
Date: Mon Feb 22 2021 - 07:43:36 EST
From: Jan Beulich <jbeulich@xxxxxxxx>
commit b512e1b077e5ccdbd6e225b15d934ab12453b70a upstream.
We should not set up further state if either mapping failed; paying
attention to just the user mapping's status isn't enough.
Also use GNTST_okay instead of implying its value (zero).
This is part of XSA-361.
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/xen/p2m.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -708,7 +708,8 @@ int set_foreign_p2m_mapping(struct gntta
unsigned long mfn, pfn;
/* Do not add to override if the map failed. */
- if (map_ops[i].status)
+ if (map_ops[i].status != GNTST_okay ||
+ (kmap_ops && kmap_ops[i].status != GNTST_okay))
continue;
if (map_ops[i].flags & GNTMAP_contains_pte) {