diff options
author | Al Viro <viro@zeniv.linux.org.uk> | 2018-05-14 00:03:34 -0400 |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2018-05-21 14:30:09 -0400 |
commit | 7b745a4e4051e1bbce40e0b1c2cf636c70583aa4 (patch) | |
tree | c5fd8a796d75053bccf60ee4376b4872d10e7918 | |
parent | 82382acec0c97b91830fff7130d0acce4ac4f3f3 (diff) |
unfuck sysfs_mount()
new_sb is left uninitialized in case of early failures in kernfs_mount_ns(),
and while IS_ERR(root) is true in all such cases, using IS_ERR(root) || !new_sb
is not a solution - IS_ERR(root) is true in some cases when new_sb is true.
Make sure new_sb is initialized (and matches the reality) in all cases and
fix the condition for dropping kobj reference - we want it done precisely
in those situations where the reference has not been transferred into a new
super_block instance.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r-- | fs/sysfs/mount.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index b428d317ae92..92682fcc41f6 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c | |||
@@ -25,7 +25,7 @@ static struct dentry *sysfs_mount(struct file_system_type *fs_type, | |||
25 | { | 25 | { |
26 | struct dentry *root; | 26 | struct dentry *root; |
27 | void *ns; | 27 | void *ns; |
28 | bool new_sb; | 28 | bool new_sb = false; |
29 | 29 | ||
30 | if (!(flags & SB_KERNMOUNT)) { | 30 | if (!(flags & SB_KERNMOUNT)) { |
31 | if (!kobj_ns_current_may_mount(KOBJ_NS_TYPE_NET)) | 31 | if (!kobj_ns_current_may_mount(KOBJ_NS_TYPE_NET)) |
@@ -35,9 +35,9 @@ static struct dentry *sysfs_mount(struct file_system_type *fs_type, | |||
35 | ns = kobj_ns_grab_current(KOBJ_NS_TYPE_NET); | 35 | ns = kobj_ns_grab_current(KOBJ_NS_TYPE_NET); |
36 | root = kernfs_mount_ns(fs_type, flags, sysfs_root, | 36 | root = kernfs_mount_ns(fs_type, flags, sysfs_root, |
37 | SYSFS_MAGIC, &new_sb, ns); | 37 | SYSFS_MAGIC, &new_sb, ns); |
38 | if (IS_ERR(root) || !new_sb) | 38 | if (!new_sb) |
39 | kobj_ns_drop(KOBJ_NS_TYPE_NET, ns); | 39 | kobj_ns_drop(KOBJ_NS_TYPE_NET, ns); |
40 | else if (new_sb) | 40 | else if (!IS_ERR(root)) |
41 | root->d_sb->s_iflags |= SB_I_USERNS_VISIBLE; | 41 | root->d_sb->s_iflags |= SB_I_USERNS_VISIBLE; |
42 | 42 | ||
43 | return root; | 43 | return root; |