[Devel] [PATCH RHEL9 COMMIT] mempolicy: Prohibit VE processes numa binding syscalls

[Konstantin Khorenko]

The commit is pushed to "branch-rh9-5.14.vz9.1.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh9-5.14.0-4.vz9.10.12
------>
commit 81f313c7272c6d97b4907972c028c8cd0384e3e6
Author: Kirill Tkhai <ktkhai at virtuozzo.com>
Date:   Wed Oct 20 11:40:44 2021 +0300

    mempolicy: Prohibit VE processes numa binding syscalls
    
    NUMA mustn't not available in CT, so let's prohibit these
    calls. For CT tasks this will look like kernel compiled
    without NUMA support.
    
    https://jira.sw.ru/browse/PSBM-92583
    
    Signed-off-by: Kirill Tkhai <ktkhai at virtuozzo.com>
    
    (cherry-picked from vz7 commit 01720c50bea3 ("mempolicy: Prohibit VE processes
    numa binding syscalls"))
    
    https://jira.sw.ru/browse/PSBM-127854
    Signed-off-by: Valeriy Vdovin <valeriy.vdovin at virtuozzo.com>
    
    (cherry picked from vz8 commit 75e78183725620559575ddce45da666dd722077f)
    Signed-off-by: Andrey Zhadchenko <andrey.zhadchenko at virtuozzo.com>
---
 mm/mempolicy.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index e32360e90274..fb58cc4cf81b 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1491,6 +1491,9 @@ static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask,
 	int lmode = mode;
 	int err;
 
+	if (!ve_is_super(get_exec_env()))
+		return -ENOSYS;
+
 	err = sanitize_mpol_flags(&lmode, &mode_flags);
 	if (err)
 		return err;
@@ -1653,6 +1656,9 @@ COMPAT_SYSCALL_DEFINE5(get_mempolicy, int __user *, policy,
 	unsigned long nr_bits, alloc_size;
 	DECLARE_BITMAP(bm, MAX_NUMNODES);
 
+	if (!ve_is_super(get_exec_env()))
+		return -ENOSYS;
+
 	nr_bits = min_t(unsigned long, maxnode-1, nr_node_ids);
 	alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
 
@@ -1702,6 +1708,9 @@ COMPAT_SYSCALL_DEFINE6(mbind, compat_ulong_t, start, compat_ulong_t, len,
 	unsigned long nr_bits, alloc_size;
 	nodemask_t bm;
 
+	if (!ve_is_super(get_exec_env()))
+		return -ENOSYS;
+
 	nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
 	alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;