[PATCH 1/4] security_util: Don't error on macOS when getting/setting/moving XATTRs

[Michal Privoznik]

There are three internal APIs implemented in this security_util
file: virSecurityGetRememberedLabel(),
virSecuritySetRememberedLabel() and
virSecurityMoveRememberedLabel() for getting, setting and moving
remembered seclabel. All three have a special return value of -2
when XATTRs are not supported (for whatever reason) and callers
are expected to handle it gracefully. However, after my commit of
v5.7.0-rc1~115 it may happen that one of the three functions
returned -1 even though XATTRs are not supported (and thus -2
should have been returned).

Fixes: 7cfb7aab573a031880a1f4fd20747843fea109ba
Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/security/security_util.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/security/security_util.c b/src/security/security_util.c
index 7fa5163fe4..622bd901ee 100644
--- a/src/security/security_util.c
+++ b/src/security/security_util.c
@@ -269,8 +269,11 @@ virSecurityGetRememberedLabel(const char *name,
 
     *label = NULL;
 
-    if (!(ref_name = virSecurityGetRefCountAttrName(name)))
+    if (!(ref_name = virSecurityGetRefCountAttrName(name))) {
+        if (errno == ENOSYS)
+            return -2;
         return -1;
+    }
 
     if (virFileGetXAttrQuiet(path, ref_name, &value) < 0) {
         if (errno == ENOSYS || errno == ENODATA || errno == ENOTSUP)
@@ -364,8 +367,11 @@ virSecuritySetRememberedLabel(const char *name,
     g_autofree char *value = NULL;
     unsigned int refcount = 0;
 
-    if (!(ref_name = virSecurityGetRefCountAttrName(name)))
+    if (!(ref_name = virSecurityGetRefCountAttrName(name))) {
+        if (errno == ENOSYS)
+            return -2;
         return -1;
+    }
 
     if (virFileGetXAttrQuiet(path, ref_name, &value) < 0) {
         if (errno == ENOSYS || errno == ENOTSUP) {
@@ -452,8 +458,11 @@ virSecurityMoveRememberedLabel(const char *name,
 
     if (!(ref_name = virSecurityGetRefCountAttrName(name)) ||
         !(attr_name = virSecurityGetAttrName(name)) ||
-        !(timestamp_name = virSecurityGetTimestampAttrName(name)))
+        !(timestamp_name = virSecurityGetTimestampAttrName(name))) {
+        if (errno == ENOSYS)
+            return -2;
         return -1;
+    }
 
     if (virFileGetXAttrQuiet(src, ref_name, &ref_value) < 0) {
         if (errno == ENOSYS || errno == ENOTSUP) {
-- 
2.26.2