From: Michal Hocko <mhocko@xxxxxxxxxx>
commit 476accbe2f6ef69caeebe99f52a286e12ac35aee upstream.
There is a strange __GFP_NOMEMALLOC usage pattern in SELinux,
specifically GFP_ATOMIC | __GFP_NOMEMALLOC which doesn't make much
sense. GFP_ATOMIC on its own allows to access memory reserves while
__GFP_NOMEMALLOC dictates we cannot use memory reserves. Replace this
with the much more sane GFP_NOWAIT in the AVC code as we can tolerate
memory allocation failures in that code.
Signed-off-by: Michal Hocko <mhocko@xxxxxxxxxx>
Acked-by: Mel Gorman <mgorman@xxxxxxx>
Signed-off-by: Paul Moore <paul@xxxxxxxxxxxxxx>
Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
---
To be applied on 4.4.y as well.
Build tested on v4.4.153.
security/selinux/avc.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)
diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index e60c79de13e1..52f3c550abcc 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -348,27 +348,26 @@ static struct avc_xperms_decision_node
struct avc_xperms_decision_node *xpd_node;
struct extended_perms_decision *xpd;
- xpd_node = kmem_cache_zalloc(avc_xperms_decision_cachep,
- GFP_ATOMIC | __GFP_NOMEMALLOC);
+ xpd_node = kmem_cache_zalloc(avc_xperms_decision_cachep, GFP_NOWAIT);
if (!xpd_node)
return NULL;
xpd = &xpd_node->xpd;
if (which & XPERMS_ALLOWED) {
xpd->allowed = kmem_cache_zalloc(avc_xperms_data_cachep,
- GFP_ATOMIC | __GFP_NOMEMALLOC);
+ GFP_NOWAIT);
if (!xpd->allowed)
goto error;
}
if (which & XPERMS_AUDITALLOW) {
xpd->auditallow = kmem_cache_zalloc(avc_xperms_data_cachep,
- GFP_ATOMIC | __GFP_NOMEMALLOC);
+ GFP_NOWAIT);
if (!xpd->auditallow)
goto error;
}
if (which & XPERMS_DONTAUDIT) {
xpd->dontaudit = kmem_cache_zalloc(avc_xperms_data_cachep,
- GFP_ATOMIC | __GFP_NOMEMALLOC);
+ GFP_NOWAIT);
if (!xpd->dontaudit)
goto error;
}
@@ -396,8 +395,7 @@ static struct avc_xperms_node *avc_xperms_alloc(void)
{
struct avc_xperms_node *xp_node;
- xp_node = kmem_cache_zalloc(avc_xperms_cachep,
- GFP_ATOMIC|__GFP_NOMEMALLOC);
+ xp_node = kmem_cache_zalloc(avc_xperms_cachep, GFP_NOWAIT);
if (!xp_node)
return xp_node;
INIT_LIST_HEAD(&xp_node->xpd_head);
@@ -550,7 +548,7 @@ static struct avc_node *avc_alloc_node(void)
{
struct avc_node *node;
- node = kmem_cache_zalloc(avc_node_cachep, GFP_ATOMIC|__GFP_NOMEMALLOC);
+ node = kmem_cache_zalloc(avc_node_cachep, GFP_NOWAIT);
if (!node)
goto out;
--
2.7.4
