Re: [PATCH v3 04/25] ima: Align ima_file_mprotect() definition with LSM infrastructure

[Roberto Sassu]

On Wed, 2023-10-11 at 10:51 -0400, Mimi Zohar wrote:
> On Mon, 2023-09-04 at 15:33 +0200, Roberto Sassu wrote:
> > From: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> > 
> > Change ima_file_mprotect() definition, so that it can be registered
> > as implementation of the file_mprotect hook.
> > 
> > Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> > Reviewed-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> > ---
> >  include/linux/ima.h               | 5 +++--
> >  security/integrity/ima/ima_main.c | 6 ++++--
> >  security/security.c               | 2 +-
> >  3 files changed, 8 insertions(+), 5 deletions(-)
> > 
> > diff --git a/include/linux/ima.h b/include/linux/ima.h
> > index 893c3b98b4d0..56e72c0beb96 100644
> > --- a/include/linux/ima.h
> > +++ b/include/linux/ima.h
> > @@ -24,7 +24,8 @@ extern void ima_post_create_tmpfile(struct mnt_idmap *idmap,
> >  extern void ima_file_free(struct file *file);
> >  extern int ima_file_mmap(struct file *file, unsigned long reqprot,
> >  			 unsigned long prot, unsigned long flags);
> > -extern int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot);
> > +int ima_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
> > +		      unsigned long prot);
> 
> "extern" is needed here and similarly in 5/25.

I removed because of a complain from checkpatch.pl --strict.

Roberto

> Mimi
> 
> >  extern int ima_load_data(enum kernel_load_data_id id, bool contents);
> >  extern int ima_post_load_data(char *buf, loff_t size,
> >  			      enum kernel_load_data_id id, char *description);
> > @@ -88,7 +89,7 @@ static inline int ima_file_mmap(struct file *file, unsigned long reqprot,
> >  }
> >  
> >  static inline int ima_file_mprotect(struct vm_area_struct *vma,
> > -				    unsigned long prot)
> > +				    unsigned long reqprot, unsigned long prot)
> >  {
> >  	return 0;
> >  }
> > diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
> > index 52e742d32f4b..e9e2a3ad25a1 100644
> > --- a/security/integrity/ima/ima_main.c
> > +++ b/security/integrity/ima/ima_main.c
> > @@ -441,7 +441,8 @@ int ima_file_mmap(struct file *file, unsigned long reqprot,
> >  /**
> >   * ima_file_mprotect - based on policy, limit mprotect change
> >   * @vma: vm_area_struct protection is set to
> > - * @prot: contains the protection that will be applied by the kernel.
> > + * @reqprot: protection requested by the application
> > + * @prot: protection that will be applied by the kernel
> >   *
> >   * Files can be mmap'ed read/write and later changed to execute to circumvent
> >   * IMA's mmap appraisal policy rules.  Due to locking issues (mmap semaphore
> > @@ -451,7 +452,8 @@ int ima_file_mmap(struct file *file, unsigned long reqprot,
> >   *
> >   * On mprotect change success, return 0.  On failure, return -EACESS.
> >   */
> > -int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot)
> > +int ima_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
> > +		      unsigned long prot)
> >  {
> >  	struct ima_template_desc *template = NULL;
> >  	struct file *file;
> > diff --git a/security/security.c b/security/security.c
> > index 96f2c68a1571..dffb67e6e119 100644
> > --- a/security/security.c
> > +++ b/security/security.c
> > @@ -2721,7 +2721,7 @@ int security_file_mprotect(struct vm_area_struct *vma, unsigned long reqprot,
> >  	ret = call_int_hook(file_mprotect, 0, vma, reqprot, prot);
> >  	if (ret)
> >  		return ret;
> > -	return ima_file_mprotect(vma, prot);
> > +	return ima_file_mprotect(vma, reqprot, prot);
> >  }
> >  
> >  /**
>