[v4,1/5] reiserfs: Add missing calls to reiserfs_security_free()

Message ID 20221110094639.3086409-2-roberto.sassu@huaweicloud.com
State New
Headers
Series evm: Prepare for moving to the LSM infrastructure |

Commit Message

Roberto Sassu Nov. 10, 2022, 9:46 a.m. UTC
  From: Roberto Sassu <roberto.sassu@huawei.com>

Commit 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes
during inode creation") defined reiserfs_security_free() to free the name
and value of a security xattr allocated by the active LSM through
security_old_inode_init_security(). However, this function is not called
in the reiserfs code.

Thus, add a call to reiserfs_security_free() whenever
reiserfs_security_init() is called, and initialize value to NULL, to avoid
to call kfree() on an uninitialized pointer.

Finally, remove the kfree() for the xattr name, as it is not allocated
anymore.

Fixes: 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes during inode creation")
Cc: stable@vger.kernel.org
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: Mimi Zohar <zohar@linux.ibm.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
---
 fs/reiserfs/namei.c          | 4 ++++
 fs/reiserfs/xattr_security.c | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)
  

Comments

Mimi Zohar Nov. 16, 2022, 9:03 p.m. UTC | #1
On Thu, 2022-11-10 at 10:46 +0100, Roberto Sassu wrote:
> From: Roberto Sassu <roberto.sassu@huawei.com>
> 
> Commit 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes
> during inode creation") defined reiserfs_security_free() to free the name
> and value of a security xattr allocated by the active LSM through
> security_old_inode_init_security(). However, this function is not called
> in the reiserfs code.
> 
> Thus, add a call to reiserfs_security_free() whenever
> reiserfs_security_init() is called, and initialize value to NULL, to avoid
> to call kfree() on an uninitialized pointer.
> 
> Finally, remove the kfree() for the xattr name, as it is not allocated
> anymore.
> 
> Fixes: 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes during inode creation")
> Cc: stable@vger.kernel.org
> Cc: Jeff Mahoney <jeffm@suse.com>
> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> Reported-by: Mimi Zohar <zohar@linux.ibm.com>
> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>

Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
  
Paul Moore Nov. 21, 2022, 11:41 p.m. UTC | #2
On Thu, Nov 10, 2022 at 4:47 AM Roberto Sassu
<roberto.sassu@huaweicloud.com> wrote:
>
> From: Roberto Sassu <roberto.sassu@huawei.com>
>
> Commit 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes
> during inode creation") defined reiserfs_security_free() to free the name
> and value of a security xattr allocated by the active LSM through
> security_old_inode_init_security(). However, this function is not called
> in the reiserfs code.
>
> Thus, add a call to reiserfs_security_free() whenever
> reiserfs_security_init() is called, and initialize value to NULL, to avoid
> to call kfree() on an uninitialized pointer.
>
> Finally, remove the kfree() for the xattr name, as it is not allocated
> anymore.
>
> Fixes: 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes during inode creation")
> Cc: stable@vger.kernel.org
> Cc: Jeff Mahoney <jeffm@suse.com>
> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> Reported-by: Mimi Zohar <zohar@linux.ibm.com>
> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> ---
>  fs/reiserfs/namei.c          | 4 ++++
>  fs/reiserfs/xattr_security.c | 2 +-
>  2 files changed, 5 insertions(+), 1 deletion(-)

If I'm understanding this patch correctly, this is a standalone
bugfix, right?  Any reason this shouldn't be merged now, independent
of the rest of patches in this patchset?

> diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c
> index 3d7a35d6a18b..b916859992ec 100644
> --- a/fs/reiserfs/namei.c
> +++ b/fs/reiserfs/namei.c
> @@ -696,6 +696,7 @@ static int reiserfs_create(struct user_namespace *mnt_userns, struct inode *dir,
>
>  out_failed:
>         reiserfs_write_unlock(dir->i_sb);
> +       reiserfs_security_free(&security);
>         return retval;
>  }
>
> @@ -779,6 +780,7 @@ static int reiserfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
>
>  out_failed:
>         reiserfs_write_unlock(dir->i_sb);
> +       reiserfs_security_free(&security);
>         return retval;
>  }
>
> @@ -878,6 +880,7 @@ static int reiserfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
>         retval = journal_end(&th);
>  out_failed:
>         reiserfs_write_unlock(dir->i_sb);
> +       reiserfs_security_free(&security);
>         return retval;
>  }
>
> @@ -1194,6 +1197,7 @@ static int reiserfs_symlink(struct user_namespace *mnt_userns,
>         retval = journal_end(&th);
>  out_failed:
>         reiserfs_write_unlock(parent_dir->i_sb);
> +       reiserfs_security_free(&security);
>         return retval;
>  }
>
> diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c
> index 8965c8e5e172..857a65b05726 100644
> --- a/fs/reiserfs/xattr_security.c
> +++ b/fs/reiserfs/xattr_security.c
> @@ -50,6 +50,7 @@ int reiserfs_security_init(struct inode *dir, struct inode *inode,
>         int error;
>
>         sec->name = NULL;
> +       sec->value = NULL;
>
>         /* Don't add selinux attributes on xattrs - they'll never get used */
>         if (IS_PRIVATE(dir))
> @@ -95,7 +96,6 @@ int reiserfs_security_write(struct reiserfs_transaction_handle *th,
>
>  void reiserfs_security_free(struct reiserfs_security_handle *sec)
>  {
> -       kfree(sec->name);
>         kfree(sec->value);
>         sec->name = NULL;
>         sec->value = NULL;
> --
> 2.25.1
>
  
Roberto Sassu Nov. 22, 2022, 8:11 a.m. UTC | #3
On Mon, 2022-11-21 at 18:41 -0500, Paul Moore wrote:
> On Thu, Nov 10, 2022 at 4:47 AM Roberto Sassu
> <roberto.sassu@huaweicloud.com> wrote:
> > From: Roberto Sassu <roberto.sassu@huawei.com>
> > 
> > Commit 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes
> > during inode creation") defined reiserfs_security_free() to free the name
> > and value of a security xattr allocated by the active LSM through
> > security_old_inode_init_security(). However, this function is not called
> > in the reiserfs code.
> > 
> > Thus, add a call to reiserfs_security_free() whenever
> > reiserfs_security_init() is called, and initialize value to NULL, to avoid
> > to call kfree() on an uninitialized pointer.
> > 
> > Finally, remove the kfree() for the xattr name, as it is not allocated
> > anymore.
> > 
> > Fixes: 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes during inode creation")
> > Cc: stable@vger.kernel.org
> > Cc: Jeff Mahoney <jeffm@suse.com>
> > Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> > Reported-by: Mimi Zohar <zohar@linux.ibm.com>
> > Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > ---
> >  fs/reiserfs/namei.c          | 4 ++++
> >  fs/reiserfs/xattr_security.c | 2 +-
> >  2 files changed, 5 insertions(+), 1 deletion(-)
> 
> If I'm understanding this patch correctly, this is a standalone
> bugfix, right?  Any reason this shouldn't be merged now, independent
> of the rest of patches in this patchset?

Yes. It would be fine for me to pick this sooner.

Thanks

Roberto

> > diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c
> > index 3d7a35d6a18b..b916859992ec 100644
> > --- a/fs/reiserfs/namei.c
> > +++ b/fs/reiserfs/namei.c
> > @@ -696,6 +696,7 @@ static int reiserfs_create(struct user_namespace *mnt_userns, struct inode *dir,
> > 
> >  out_failed:
> >         reiserfs_write_unlock(dir->i_sb);
> > +       reiserfs_security_free(&security);
> >         return retval;
> >  }
> > 
> > @@ -779,6 +780,7 @@ static int reiserfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
> > 
> >  out_failed:
> >         reiserfs_write_unlock(dir->i_sb);
> > +       reiserfs_security_free(&security);
> >         return retval;
> >  }
> > 
> > @@ -878,6 +880,7 @@ static int reiserfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
> >         retval = journal_end(&th);
> >  out_failed:
> >         reiserfs_write_unlock(dir->i_sb);
> > +       reiserfs_security_free(&security);
> >         return retval;
> >  }
> > 
> > @@ -1194,6 +1197,7 @@ static int reiserfs_symlink(struct user_namespace *mnt_userns,
> >         retval = journal_end(&th);
> >  out_failed:
> >         reiserfs_write_unlock(parent_dir->i_sb);
> > +       reiserfs_security_free(&security);
> >         return retval;
> >  }
> > 
> > diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c
> > index 8965c8e5e172..857a65b05726 100644
> > --- a/fs/reiserfs/xattr_security.c
> > +++ b/fs/reiserfs/xattr_security.c
> > @@ -50,6 +50,7 @@ int reiserfs_security_init(struct inode *dir, struct inode *inode,
> >         int error;
> > 
> >         sec->name = NULL;
> > +       sec->value = NULL;
> > 
> >         /* Don't add selinux attributes on xattrs - they'll never get used */
> >         if (IS_PRIVATE(dir))
> > @@ -95,7 +96,6 @@ int reiserfs_security_write(struct reiserfs_transaction_handle *th,
> > 
> >  void reiserfs_security_free(struct reiserfs_security_handle *sec)
> >  {
> > -       kfree(sec->name);
> >         kfree(sec->value);
> >         sec->name = NULL;
> >         sec->value = NULL;
> > --
> > 2.25.1
> > 
> 
>
  
Paul Moore Nov. 22, 2022, 10:47 p.m. UTC | #4
On Tue, Nov 22, 2022 at 3:12 AM Roberto Sassu
<roberto.sassu@huaweicloud.com> wrote:
> On Mon, 2022-11-21 at 18:41 -0500, Paul Moore wrote:
> > On Thu, Nov 10, 2022 at 4:47 AM Roberto Sassu
> > <roberto.sassu@huaweicloud.com> wrote:
> > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > >
> > > Commit 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes
> > > during inode creation") defined reiserfs_security_free() to free the name
> > > and value of a security xattr allocated by the active LSM through
> > > security_old_inode_init_security(). However, this function is not called
> > > in the reiserfs code.
> > >
> > > Thus, add a call to reiserfs_security_free() whenever
> > > reiserfs_security_init() is called, and initialize value to NULL, to avoid
> > > to call kfree() on an uninitialized pointer.
> > >
> > > Finally, remove the kfree() for the xattr name, as it is not allocated
> > > anymore.
> > >
> > > Fixes: 57fe60df6241 ("reiserfs: add atomic addition of selinux attributes during inode creation")
> > > Cc: stable@vger.kernel.org
> > > Cc: Jeff Mahoney <jeffm@suse.com>
> > > Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> > > Reported-by: Mimi Zohar <zohar@linux.ibm.com>
> > > Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > ---
> > >  fs/reiserfs/namei.c          | 4 ++++
> > >  fs/reiserfs/xattr_security.c | 2 +-
> > >  2 files changed, 5 insertions(+), 1 deletion(-)
> >
> > If I'm understanding this patch correctly, this is a standalone
> > bugfix, right?  Any reason this shouldn't be merged now, independent
> > of the rest of patches in this patchset?
>
> Yes. It would be fine for me to pick this sooner.

Okay, as it's been almost two weeks with no comments from the reiserfs
folks and this looks okay to me I'm going to go ahead and pull this
into the lsm/next branch as it's at least "LSM adjacent" :)  As it is
lsm/next and not lsm/stable-6.1, this should give the reiserfs folks
another couple of weeks to object if they find this to be problematic.

Thanks all.
  

Patch

diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c
index 3d7a35d6a18b..b916859992ec 100644
--- a/fs/reiserfs/namei.c
+++ b/fs/reiserfs/namei.c
@@ -696,6 +696,7 @@  static int reiserfs_create(struct user_namespace *mnt_userns, struct inode *dir,
 
 out_failed:
 	reiserfs_write_unlock(dir->i_sb);
+	reiserfs_security_free(&security);
 	return retval;
 }
 
@@ -779,6 +780,7 @@  static int reiserfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
 
 out_failed:
 	reiserfs_write_unlock(dir->i_sb);
+	reiserfs_security_free(&security);
 	return retval;
 }
 
@@ -878,6 +880,7 @@  static int reiserfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 	retval = journal_end(&th);
 out_failed:
 	reiserfs_write_unlock(dir->i_sb);
+	reiserfs_security_free(&security);
 	return retval;
 }
 
@@ -1194,6 +1197,7 @@  static int reiserfs_symlink(struct user_namespace *mnt_userns,
 	retval = journal_end(&th);
 out_failed:
 	reiserfs_write_unlock(parent_dir->i_sb);
+	reiserfs_security_free(&security);
 	return retval;
 }
 
diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c
index 8965c8e5e172..857a65b05726 100644
--- a/fs/reiserfs/xattr_security.c
+++ b/fs/reiserfs/xattr_security.c
@@ -50,6 +50,7 @@  int reiserfs_security_init(struct inode *dir, struct inode *inode,
 	int error;
 
 	sec->name = NULL;
+	sec->value = NULL;
 
 	/* Don't add selinux attributes on xattrs - they'll never get used */
 	if (IS_PRIVATE(dir))
@@ -95,7 +96,6 @@  int reiserfs_security_write(struct reiserfs_transaction_handle *th,
 
 void reiserfs_security_free(struct reiserfs_security_handle *sec)
 {
-	kfree(sec->name);
 	kfree(sec->value);
 	sec->name = NULL;
 	sec->value = NULL;