Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
copy_mnt_ns(): use guards
* mntput() of rootmnt and pwdmnt done via __free(mntput)
* mnt_ns_tree_add() can be done within namespace_excl scope.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
+4
-12
+4
-12
fs/namespace.c
+4
-12
fs/namespace.c
···
4158
4158
struct user_namespace *user_ns, struct fs_struct *new_fs)
4159
4159
{
4160
4160
struct mnt_namespace *new_ns;
4161
-
struct vfsmount *rootmnt = NULL, *pwdmnt = NULL;
4161
+
struct vfsmount *rootmnt __free(mntput) = NULL;
4162
+
struct vfsmount *pwdmnt __free(mntput) = NULL;
4162
4163
struct mount *p, *q;
4163
4164
struct mount *old;
4164
4165
struct mount *new;
···
4178
4177
if (IS_ERR(new_ns))
4179
4178
return new_ns;
4180
4179
4181
-
namespace_lock();
4180
+
guard(namespace_excl)();
4182
4181
/* First pass: copy the tree topology */
4183
4182
copy_flags = CL_COPY_UNBINDABLE | CL_EXPIRE;
4184
4183
if (user_ns != ns->user_ns)
···
4186
4185
new = copy_tree(old, old->mnt.mnt_root, copy_flags);
4187
4186
if (IS_ERR(new)) {
4188
4187
emptied_ns = new_ns;
4189
-
namespace_unlock();
4190
4188
return ERR_CAST(new);
4191
4189
}
4192
4190
if (user_ns != ns->user_ns) {
4193
-
lock_mount_hash();
4191
+
guard(mount_writer)();
4194
4192
lock_mnt_tree(new);
4195
-
unlock_mount_hash();
4196
4193
}
4197
4194
new_ns->root = new;
4198
4195
···
4222
4223
while (p->mnt.mnt_root != q->mnt.mnt_root)
4223
4224
p = next_mnt(skip_mnt_tree(p), old);
4224
4225
}
4225
-
namespace_unlock();
4226
-
4227
-
if (rootmnt)
4228
-
mntput(rootmnt);
4229
-
if (pwdmnt)
4230
-
mntput(pwdmnt);
4231
-
4232
4226
mnt_ns_tree_add(new_ns);
4233
4227
return new_ns;
4234
4228
}