From: Michael Kerrisk This patch fixes utimensat() to make its behavior consistent with that of utime()/utimes() when dealing with files marked immutable and append-only. The current utimensat() implementation also returns EPERM if 'times' is non-NULL and the tv_nsec fields are both UTIME_NOW. For consistency, the (times != NULL && times[0].tv_nsec == UTIME_NOW && times[1].tv_nsec == UTIME_NOW) case should be treated like the traditional utimes() case where 'times' is NULL. That is, the call should succeed for a file marked append-only and should give the error EACCES if the file is marked as immutable. The simple way to do this is to set 'times' to NULL if (times[0].tv_nsec == UTIME_NOW && times[1].tv_nsec == UTIME_NOW). This is also the natural approach, since POSIX.1 semantics consider the times == {{x, UTIME_NOW}, {y, UTIME_NOW}} to be exactly equivalent to the case for times == NULL. (Thanks to Miklos for pointing this out.) Patch 3 in this series relies on the simplification provided by this patch. Acked-by: Miklos Szeredi Cc: Al Viro Cc: Ulrich Drepper Signed-off-by: Michael Kerrisk Signed-off-by: Andrew Morton --- fs/utimes.c | 4 ++++ 1 file changed, 4 insertions(+) diff -puN fs/utimes.c~vfs-utimensat-be-consistent-with-utime-for-immutable-and-append-only-files fs/utimes.c --- a/fs/utimes.c~vfs-utimensat-be-consistent-with-utime-for-immutable-and-append-only-files +++ a/fs/utimes.c @@ -102,6 +102,10 @@ long do_utimes(int dfd, char __user *fil if (error) goto dput_and_out; + if (times && times[0].tv_nsec == UTIME_NOW && + times[1].tv_nsec == UTIME_NOW) + times = NULL; + /* Don't worry, the checks are done in inode_change_ok() */ newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME; if (times) { _