[libvirt] [PATCH 2/3] util: virfile: Clarify setuid usage for virFileRemove

Break these checks out into their own function, and clearly document each one. This shouldn't change behavior --- src/util/virfile.c | 33 +++++++++++++++++++++++++++------ 1 file changed, 27 insertions(+), 6 deletions(-) diff --git a/src/util/virfile.c b/src/util/virfile.c index f45e18f..cea2674 100644 --- a/src/util/virfile.c +++ b/src/util/virfile.c @@ -2314,6 +2314,32 @@ virFileOpenAs(const char *path, int openflags, mode_t mode, } +/* virFileRemoveNeedsSetuid: + * @uid: file uid to check + * @gid: file gid to check + * + * Return true if we should use setuid/setgid before deleting a file + * owned by the passed uid/gid pair. Needed for NFS with root-squash + */ +static bool +virFileRemoveNeedsSetuid(uid_t uid, gid_t gid) +{ + /* If running unprivileged, setuid isn't going to work */ + if (geteuid() != 0) + return false; + + /* uid/gid weren'd specified */ + if ((uid == (uid_t) -1) && (gid == (gid_t) -1)) + return false; + + /* already running as proper uid/gid */ + if (uid == geteuid() && gid == getegid()) + return false; + + return true; +} + + /* virFileRemove: * @path: file to unlink or directory to remove * @uid: uid that was used to create the file (not required) @@ -2335,12 +2361,7 @@ virFileRemove(const char *path, gid_t *groups; int ngroups; - /* If not running as root or if a non explicit uid/gid was being used for - * the file/volume or the explicit uid/gid matches, then use unlink directly - */ - if ((geteuid() != 0) || - ((uid == (uid_t) -1) && (gid == (gid_t) -1)) || - (uid == geteuid() && gid == getegid())) { + if (!virFileRemoveNeedsSetuid(uid, gid)) { if (virFileIsDir(path)) return rmdir(path); else -- 2.5.0