[libvirt] [PATCH 3/3] util: virfile: Only setuid for virFileRemove if on NFS

[Cole Robinson]

NFS with root-squash is the only reason we need to do setuid/setgid
crazyness in virFileRemove, so limit that behavior to the NFS case.
---
I'm not sure though if NFS is the only case we care about this here,
or if we want to conditionalize this path on NFS since that makes it
more of a pain to test... It's not required to fix the initial bug

 src/util/virfile.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/util/virfile.c b/src/util/virfile.c
index cea2674..3d1b118 100644
--- a/src/util/virfile.c
+++ b/src/util/virfile.c
@@ -2322,7 +2322,7 @@ virFileOpenAs(const char *path, int openflags, mode_t mode,
  * owned by the passed uid/gid pair. Needed for NFS with root-squash
  */
 static bool
-virFileRemoveNeedsSetuid(uid_t uid, gid_t gid)
+virFileRemoveNeedsSetuid(const char *path, uid_t uid, gid_t gid)
 {
     /* If running unprivileged, setuid isn't going to work */
     if (geteuid() != 0)
@@ -2336,6 +2336,12 @@ virFileRemoveNeedsSetuid(uid_t uid, gid_t gid)
     if (uid == geteuid() && gid == getegid())
         return false;
 
+    /* Only perform the setuid stuff for NFS, which is the only case
+       that may actually need it. This can error, but just be safe and
+       only check for a clear negative result. */
+    if (virFileIsSharedFSType(path, VIR_FILE_SHFS_NFS) == 0)
+        return false;
+
     return true;
 }
 
@@ -2361,7 +2367,7 @@ virFileRemove(const char *path,
     gid_t *groups;
     int ngroups;
 
-    if (!virFileRemoveNeedsSetuid(uid, gid)) {
+    if (!virFileRemoveNeedsSetuid(path, uid, gid)) {
         if (virFileIsDir(path))
             return rmdir(path);
         else
-- 
2.5.0