related to: https://bugs.launchpad.net/ecryptfs/+bug/1890486 This bug happens in the two following situations: cp -p: copy a file and preserve its atime and mtime touch -r: touch a file and use a ref file's time instead of current time In fs/attr.c notify_change(), atime and mtime is truncated by timestamp_truncate(), ecryptfs gets wrong s_time_gran (10^9 instead of original fs time granularity) and truncates a/mtime to whole second. Setting s_time_gran when mounting ecryptfs solves the issue. Signed-off-by: Frank Hsiao 蕭法宣 <frankhsiao@xxxxxxxx> diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index b2f6a1937d239..19dbe9d1187e1 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -567,6 +567,7 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags s->s_blocksize = path.dentry->d_sb->s_blocksize; s->s_magic = ECRYPTFS_SUPER_MAGIC; s->s_stack_depth = path.dentry->d_sb->s_stack_depth + 1; + s->s_time_gran = path.dentry->d_sb->s_time_gran; rc = -EINVAL; if (s->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) {
