chase: drop CHASE_AT_RESOLVE_IN_ROOT when AT_FDCWD or root dir fd is specified

If we get AT_FDCWD or root dir fd, we always resolve symlinks relative to the host's root. Hence, the flag is meaningless.
2023-03-30 16:29:37 +09:00
parent c4406ff710
commit e115daa6a8
1 changed files with 14 additions and 0 deletions
@@ -164,6 +164,20 @@ int chaseat(
         *    the mount point is emitted. CHASE_WARN cannot be used in PID 1.
         */

+        if (FLAGS_SET(flags, CHASE_AT_RESOLVE_IN_ROOT)) {
+                /* If we get AT_FDCWD or dir_fd points to "/", then we always resolve symlinks relative to
+                 * the host's root. Hence, CHASE_AT_RESOLVE_IN_ROOT is meaningless. */
+
+                if (dir_fd >= 0)
+                        r = dir_fd_is_root(dir_fd);
+                else
+                        r = true;
+                if (r < 0)
+                        return r;
+                if (r > 0)
+                        flags &= ~CHASE_AT_RESOLVE_IN_ROOT;
+        }
+
        if (!(flags &
              (CHASE_AT_RESOLVE_IN_ROOT|CHASE_NONEXISTENT|CHASE_NO_AUTOFS|CHASE_SAFE|CHASE_STEP|
               CHASE_PROHIBIT_SYMLINKS|CHASE_MKDIR_0755)) &&