mirror of
https://github.com/FEX-Emu/linux.git
synced 2024-12-12 10:55:08 +00:00
sysfs: correctly handle short reads on PREALLOC attrs.
attributes declared with __ATTR_PREALLOC use sysfs_kf_read() which ignores the 'count' arg. So a 1-byte read request can return more bytes than that. This is seen with the 'dash' shell when 'read' is used on some 'md' sysfs attributes. So only return the 'min' of count and the attribute length. Signed-off-by: NeilBrown <neilb@suse.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
cfcf6a91aa
commit
65da3484d9
@ -108,6 +108,7 @@ 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
|
||||
@ -115,7 +116,8 @@ static ssize_t sysfs_kf_read(struct kernfs_open_file *of, char *buf,
|
||||
*/
|
||||
if (pos || 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);
|
||||
return min(count, len);
|
||||
}
|
||||
|
||||
/* kernfs write callback for regular sysfs files */
|
||||
|
Loading…
Reference in New Issue
Block a user