diff options
Diffstat (limited to 'fs/sysfs/file.c')
| -rw-r--r-- | fs/sysfs/file.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 7c2867b44141..167f80e8f08d 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -108,14 +108,22 @@ static ssize_t sysfs_kf_read(struct kernfs_open_file *of, char *buf, { const struct sysfs_ops *ops = sysfs_file_ops(of->kn); struct kobject *kobj = of->kn->parent->priv; + size_t len; /* * If buf != of->prealloc_buf, we don't know how * large it is, so cannot safely pass it to ->show */ - if (pos || WARN_ON_ONCE(buf != of->prealloc_buf)) + if (WARN_ON_ONCE(buf != of->prealloc_buf)) return 0; - return ops->show(kobj, of->kn->priv, buf); + len = ops->show(kobj, of->kn->priv, buf); + if (pos) { + if (len <= pos) + return 0; + len -= pos; + memmove(buf, buf + pos, len); + } + return min(count, len); } /* kernfs write callback for regular sysfs files */ |