[PATCH] selinuxfs: Fix the resource leak in the failed branch of sel_make_inode

[Paul Moore]

On Tue, Aug 7, 2018 at 5:35 PM Paul Moore <paul at paul-moore.com> wrote:
>
> On Sun, Aug 5, 2018 at 5:48 AM nixiaoming <nixiaoming at huawei.com> wrote:
> > If the resource requested by d_alloc_name is not added to the linked
> > list through d_add, then dput needs to be called to release the
> > subsequent abnormal branch to avoid resource leakage.
> >
> > Add missing dput to selinuxfs.c
> >
> > Signed-off-by: nixiaoming <nixiaoming at huawei.com>
> > ---
> >  security/selinux/selinuxfs.c | 33 +++++++++++++++++++++++++--------
> >  1 file changed, 25 insertions(+), 8 deletions(-)
>
> Thanks for the quick follow-up on this patch.  It looks okay to me,
> assuming my test kernel works correctly (it's building now) I'll merge
> this into selinux/next.

Merged into selinux/next, thanks!

> > diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
> > index 79d3709..0b66d728 100644
> > --- a/security/selinux/selinuxfs.c
> > +++ b/security/selinux/selinuxfs.c
> > @@ -1365,13 +1365,18 @@ static int sel_make_bools(struct selinux_fs_info *fsi)
> >
> >                 ret = -ENOMEM;
> >                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
> > -               if (!inode)
> > +               if (!inode) {
> > +                       dput(dentry);
> >                         goto out;
> > +               }
> >
> >                 ret = -ENAMETOOLONG;
> >                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
> > -               if (len >= PAGE_SIZE)
> > +               if (len >= PAGE_SIZE) {
> > +                       dput(dentry);
> > +                       iput(inode);
> >                         goto out;
> > +               }
> >
> >                 isec = (struct inode_security_struct *)inode->i_security;
> >                 ret = security_genfs_sid(fsi->state, "selinuxfs", page,
> > @@ -1586,8 +1591,10 @@ static int sel_make_avc_files(struct dentry *dir)
> >                         return -ENOMEM;
> >
> >                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
> > -               if (!inode)
> > +               if (!inode) {
> > +                       dput(dentry);
> >                         return -ENOMEM;
> > +               }
> >
> >                 inode->i_fop = files[i].ops;
> >                 inode->i_ino = ++fsi->last_ino;
> > @@ -1632,8 +1639,10 @@ static int sel_make_initcon_files(struct dentry *dir)
> >                         return -ENOMEM;
> >
> >                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
> > -               if (!inode)
> > +               if (!inode) {
> > +                       dput(dentry);
> >                         return -ENOMEM;
> > +               }
> >
> >                 inode->i_fop = &sel_initcon_ops;
> >                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
> > @@ -1733,8 +1742,10 @@ static int sel_make_perm_files(char *objclass, int classvalue,
> >
> >                 rc = -ENOMEM;
> >                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
> > -               if (!inode)
> > +               if (!inode) {
> > +                       dput(dentry);
> >                         goto out;
> > +               }
> >
> >                 inode->i_fop = &sel_perm_ops;
> >                 /* i+1 since perm values are 1-indexed */
> > @@ -1763,8 +1774,10 @@ static int sel_make_class_dir_entries(char *classname, int index,
> >                 return -ENOMEM;
> >
> >         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
> > -       if (!inode)
> > +       if (!inode) {
> > +               dput(dentry);
> >                 return -ENOMEM;
> > +       }
> >
> >         inode->i_fop = &sel_class_ops;
> >         inode->i_ino = sel_class_to_ino(index);
> > @@ -1838,8 +1851,10 @@ static int sel_make_policycap(struct selinux_fs_info *fsi)
> >                         return -ENOMEM;
> >
> >                 inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
> > -               if (inode == NULL)
> > +               if (inode == NULL) {
> > +                       dput(dentry);
> >                         return -ENOMEM;
> > +               }
> >
> >                 inode->i_fop = &sel_policycap_ops;
> >                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
> > @@ -1932,8 +1947,10 @@ static int sel_fill_super(struct super_block *sb, void *data, int silent)
> >
> >         ret = -ENOMEM;
> >         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
> > -       if (!inode)
> > +       if (!inode) {
> > +               dput(dentry);
> >                 goto err;
> > +       }
> >
> >         inode->i_ino = ++fsi->last_ino;
> >         isec = (struct inode_security_struct *)inode->i_security;
> > --
> > 2.10.1
> >
> > --
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>
>
>
> --
> paul moore
> www.paul-moore.com



-- 
paul moore
www.paul-moore.com
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