vfs: fix permission checking in sys_utimensat

[safe/jmp/linux-2.6] / fs / utimes.c

diff --git a/fs/utimes.c b/fs/utimes.c
index a2bef77..af059d5 100644 (file)
--- a/fs/utimes.c
+++ b/fs/utimes.c
@@ -40,9 +40,14 @@ asmlinkage long sys_utime(char __user *filename, struct utimbuf __user *times)
 
 #endif
 
+static bool nsec_special(long nsec)
+{
+       return nsec == UTIME_OMIT || nsec == UTIME_NOW;
+}
+
 static bool nsec_valid(long nsec)
 {
-       if (nsec == UTIME_OMIT || nsec == UTIME_NOW)
+       if (nsec_special(nsec))
                return true;
 
        return nsec >= 0 && nsec <= 999999999;
@@ -119,7 +124,15 @@ long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags
                        newattrs.ia_mtime.tv_nsec = times[1].tv_nsec;
                        newattrs.ia_valid |= ATTR_MTIME_SET;
                }
-       } else {
+       }
+
+       /*
+        * If times is NULL or both times are either UTIME_OMIT or
+        * UTIME_NOW, then need to check permissions, because
+        * inode_change_ok() won't do it.
+        */
+       if (!times || (nsec_special(times[0].tv_nsec) &&
+                      nsec_special(times[1].tv_nsec))) {
                error = -EACCES;
                 if (IS_IMMUTABLE(inode))
                        goto mnt_drop_write_and_out;