[patch for 2.6.26 3/4] vfs: utimensat(): fix error checking for {UTIME_NOW,UTIME_OMIT...

[cascardo/linux.git] / fs / utimes.c

diff --git a/fs/utimes.c b/fs/utimes.c
index d466bc5..118d1c3 100644 (file)
--- a/fs/utimes.c
+++ b/fs/utimes.c
@@ -40,14 +40,9 @@ 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_special(nsec))
+       if (nsec == UTIME_OMIT || nsec == UTIME_NOW)
                return true;
 
        return nsec >= 0 && nsec <= 999999999;
@@ -106,7 +101,7 @@ long do_utimes(int dfd, char __user *filename, struct timespec *times, int flags
                     times[1].tv_nsec == UTIME_NOW)
                times = NULL;
 
-       /* Don't worry, the checks are done in inode_change_ok() */
+       /* In most cases, the checks are done in inode_change_ok() */
        newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
        if (times) {
                error = -EPERM;
@@ -128,15 +123,26 @@ 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;
                }
-       }
 
-       /*
-        * 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))) {
+               /*
+                * For the UTIME_OMIT/UTIME_NOW and UTIME_NOW/UTIME_OMIT
+                * cases, we need to make an extra check that is not done by
+                * inode_change_ok().
+                */
+               if (((times[0].tv_nsec == UTIME_NOW &&
+                           times[1].tv_nsec == UTIME_OMIT)
+                    ||
+                    (times[0].tv_nsec == UTIME_OMIT &&
+                           times[1].tv_nsec == UTIME_NOW))
+                   && !is_owner_or_cap(inode))
+                       goto mnt_drop_write_and_out;
+       } else {
+
+               /*
+                * If times is NULL (or both times are UTIME_NOW),
+                * then we need to check permissions, because
+                * inode_change_ok() won't do it.
+                */
                error = -EACCES;
                 if (IS_IMMUTABLE(inode))
                        goto mnt_drop_write_and_out;