Re: [libvirt] [PATCH] util: Don't try to fchown files opened as non-root

When virFileOpenAs is called with VIR_FILE_OPEN_AS_UID flag and uid/gid different from root/root while libvirtd is running as root, we fork a new child, change its effective UID/GID to uid/gid and run virFileOpenAsNoFork. It doesn't make any sense to fchown() the opened file in this case since we already know that uid/gid can access the file when open succeeds and one of the following situations may happen: - the file is already owned by uid/gid and we skip fchown even before this patch - the file is owned by uid but not gid because it was created in a directory with SETGID set, in which case it is desirable not to change the group - the file may be owned by a completely different user and/or group because it was created on a root-squashed or even all-squashed NFS filesystem, in which case fchown would most likely fail anyway --- src/util/util.c | 31 +++++++++++++++++++------------ 1 files changed, 19 insertions(+), 12 deletions(-)

+ /* VIR_FILE_OPEN_AS_UID in flags means we are running in a child process + * owned by uid and gid */ + if (!(flags & VIR_FILE_OPEN_AS_UID)) { + struct stat st; + if (fstat(fd, &st) == -1) {