diff mbox series

[1/2] audit: add support for the openat2 syscall

Message ID 49510cacfb5fbbaa312a4a389f3a6619675007ab.1616031035.git.rgb@redhat.com (mailing list archive)
State Awaiting Upstream
Headers show
Series [1/2] audit: add support for the openat2 syscall | expand

Commit Message

Richard Guy Briggs March 18, 2021, 1:47 a.m. UTC
The openat2(2) syscall was added in kernel v5.6 with commit fddb5d430ad9
("open: introduce openat2(2) syscall")

Add the openat2(2) syscall to the audit syscall classifier.

See the github issue
https://github.com/linux-audit/audit-kernel/issues/67

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
---
 arch/alpha/kernel/audit.c          | 2 ++
 arch/ia64/kernel/audit.c           | 2 ++
 arch/parisc/kernel/audit.c         | 2 ++
 arch/parisc/kernel/compat_audit.c  | 2 ++
 arch/powerpc/kernel/audit.c        | 2 ++
 arch/powerpc/kernel/compat_audit.c | 2 ++
 arch/s390/kernel/audit.c           | 2 ++
 arch/s390/kernel/compat_audit.c    | 2 ++
 arch/sparc/kernel/audit.c          | 2 ++
 arch/sparc/kernel/compat_audit.c   | 2 ++
 arch/x86/ia32/audit.c              | 2 ++
 arch/x86/kernel/audit_64.c         | 2 ++
 kernel/auditsc.c                   | 3 +++
 lib/audit.c                        | 4 ++++
 lib/compat_audit.c                 | 4 ++++
 15 files changed, 35 insertions(+)

Comments

Christian Brauner March 18, 2021, 10:48 a.m. UTC | #1
[+Cc Aleksa, the author of openat2()]

and a comment below. :)

On Wed, Mar 17, 2021 at 09:47:17PM -0400, Richard Guy Briggs wrote:
> The openat2(2) syscall was added in kernel v5.6 with commit fddb5d430ad9
> ("open: introduce openat2(2) syscall")
> 
> Add the openat2(2) syscall to the audit syscall classifier.
> 
> See the github issue
> https://github.com/linux-audit/audit-kernel/issues/67
> 
> Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
> ---
>  arch/alpha/kernel/audit.c          | 2 ++
>  arch/ia64/kernel/audit.c           | 2 ++
>  arch/parisc/kernel/audit.c         | 2 ++
>  arch/parisc/kernel/compat_audit.c  | 2 ++
>  arch/powerpc/kernel/audit.c        | 2 ++
>  arch/powerpc/kernel/compat_audit.c | 2 ++
>  arch/s390/kernel/audit.c           | 2 ++
>  arch/s390/kernel/compat_audit.c    | 2 ++
>  arch/sparc/kernel/audit.c          | 2 ++
>  arch/sparc/kernel/compat_audit.c   | 2 ++
>  arch/x86/ia32/audit.c              | 2 ++
>  arch/x86/kernel/audit_64.c         | 2 ++
>  kernel/auditsc.c                   | 3 +++
>  lib/audit.c                        | 4 ++++
>  lib/compat_audit.c                 | 4 ++++
>  15 files changed, 35 insertions(+)
> 
> diff --git a/arch/alpha/kernel/audit.c b/arch/alpha/kernel/audit.c
> index 96a9d18ff4c4..06a911b685d1 100644
> --- a/arch/alpha/kernel/audit.c
> +++ b/arch/alpha/kernel/audit.c
> @@ -42,6 +42,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
>  		return 3;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 0;
>  	}
> diff --git a/arch/ia64/kernel/audit.c b/arch/ia64/kernel/audit.c
> index 5192ca899fe6..5eaa888c8fd3 100644
> --- a/arch/ia64/kernel/audit.c
> +++ b/arch/ia64/kernel/audit.c
> @@ -43,6 +43,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
>  		return 3;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 0;
>  	}
> diff --git a/arch/parisc/kernel/audit.c b/arch/parisc/kernel/audit.c
> index 9eb47b2225d2..fc721a7727ba 100644
> --- a/arch/parisc/kernel/audit.c
> +++ b/arch/parisc/kernel/audit.c
> @@ -52,6 +52,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
>  		return 3;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 0;
>  	}
> diff --git a/arch/parisc/kernel/compat_audit.c b/arch/parisc/kernel/compat_audit.c
> index 20c39c9d86a9..fc6d35918c44 100644
> --- a/arch/parisc/kernel/compat_audit.c
> +++ b/arch/parisc/kernel/compat_audit.c
> @@ -35,6 +35,8 @@ int parisc32_classify_syscall(unsigned syscall)
>  		return 3;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 1;
>  	}
> diff --git a/arch/powerpc/kernel/audit.c b/arch/powerpc/kernel/audit.c
> index a2dddd7f3d09..8f32700b0baa 100644
> --- a/arch/powerpc/kernel/audit.c
> +++ b/arch/powerpc/kernel/audit.c
> @@ -54,6 +54,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
>  		return 4;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 0;
>  	}
> diff --git a/arch/powerpc/kernel/compat_audit.c b/arch/powerpc/kernel/compat_audit.c
> index 55c6ccda0a85..ebe45534b1c9 100644
> --- a/arch/powerpc/kernel/compat_audit.c
> +++ b/arch/powerpc/kernel/compat_audit.c
> @@ -38,6 +38,8 @@ int ppc32_classify_syscall(unsigned syscall)
>  		return 4;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 1;
>  	}
> diff --git a/arch/s390/kernel/audit.c b/arch/s390/kernel/audit.c
> index d395c6c9944c..d964cb94cfaf 100644
> --- a/arch/s390/kernel/audit.c
> +++ b/arch/s390/kernel/audit.c
> @@ -54,6 +54,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
>  		return 4;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 0;
>  	}
> diff --git a/arch/s390/kernel/compat_audit.c b/arch/s390/kernel/compat_audit.c
> index 444fb1f66944..f7b32933ce0e 100644
> --- a/arch/s390/kernel/compat_audit.c
> +++ b/arch/s390/kernel/compat_audit.c
> @@ -39,6 +39,8 @@ int s390_classify_syscall(unsigned syscall)
>  		return 4;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 1;
>  	}
> diff --git a/arch/sparc/kernel/audit.c b/arch/sparc/kernel/audit.c
> index a6e91bf34d48..b6dcca9c6520 100644
> --- a/arch/sparc/kernel/audit.c
> +++ b/arch/sparc/kernel/audit.c
> @@ -55,6 +55,8 @@ int audit_classify_syscall(int abi, unsigned int syscall)
>  		return 4;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 0;
>  	}
> diff --git a/arch/sparc/kernel/compat_audit.c b/arch/sparc/kernel/compat_audit.c
> index 10eeb4f15b20..d2652a1083ad 100644
> --- a/arch/sparc/kernel/compat_audit.c
> +++ b/arch/sparc/kernel/compat_audit.c
> @@ -39,6 +39,8 @@ int sparc32_classify_syscall(unsigned int syscall)
>  		return 4;
>  	case __NR_execve:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 1;
>  	}
> diff --git a/arch/x86/ia32/audit.c b/arch/x86/ia32/audit.c
> index 6efe6cb3768a..57a02ade5503 100644
> --- a/arch/x86/ia32/audit.c
> +++ b/arch/x86/ia32/audit.c
> @@ -39,6 +39,8 @@ int ia32_classify_syscall(unsigned syscall)
>  	case __NR_execve:
>  	case __NR_execveat:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 1;
>  	}
> diff --git a/arch/x86/kernel/audit_64.c b/arch/x86/kernel/audit_64.c
> index 83d9cad4e68b..39de1e021258 100644
> --- a/arch/x86/kernel/audit_64.c
> +++ b/arch/x86/kernel/audit_64.c
> @@ -53,6 +53,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
>  	case __NR_execve:
>  	case __NR_execveat:
>  		return 5;
> +	case __NR_openat2:
> +		return 6;
>  	default:
>  		return 0;
>  	}
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 8bb9ac84d2fb..f5616e70d129 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -76,6 +76,7 @@
>  #include <linux/fsnotify_backend.h>
>  #include <uapi/linux/limits.h>
>  #include <uapi/linux/netfilter/nf_tables.h>
> +#include <uapi/linux/openat2.h>
>  
>  #include "audit.h"
>  
> @@ -195,6 +196,8 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
>  		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
>  	case 5: /* execve */
>  		return mask & AUDIT_PERM_EXEC;
> +	case 6: /* openat2 */
> +		return mask & ACC_MODE((u32)((struct open_how *)ctx->argv[2])->flags);

That looks a bit dodgy. Maybe sm like the below would be a bit better?

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 47fb48f42c93..531e882a5096 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -159,6 +159,7 @@ static const struct audit_nfcfgop_tab audit_nfcfgs[] = {

 static int audit_match_perm(struct audit_context *ctx, int mask)
 {
+       struct open_how *openat2;
        unsigned n;
        if (unlikely(!ctx))
                return 0;
@@ -195,6 +196,12 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
                return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
        case 5: /* execve */
                return mask & AUDIT_PERM_EXEC;
+       case 6: /* openat2 */
+               openat2 = ctx->argv[2];
+               if (upper_32_bits(openat2->flags))
+                       pr_warn("Some sensible warning about unknown flags");
+
+               return mask & ACC_MODE(lower_32_bits(openat2->flags));
        default:
                return 0;
        }

(Ideally we'd probably notice at build-time that we've got flags
exceeding 32bits. Could probably easily been done by exposing an all
flags macro somewhere and then we can place a BUILD_BUG_ON() or sm into
such places.)

Christian
Christian Brauner March 18, 2021, 10:52 a.m. UTC | #2
On Thu, Mar 18, 2021 at 11:48:45AM +0100, Christian Brauner wrote:
> [+Cc Aleksa, the author of openat2()]
> 
> and a comment below. :)
> 
> On Wed, Mar 17, 2021 at 09:47:17PM -0400, Richard Guy Briggs wrote:
> > The openat2(2) syscall was added in kernel v5.6 with commit fddb5d430ad9
> > ("open: introduce openat2(2) syscall")
> > 
> > Add the openat2(2) syscall to the audit syscall classifier.
> > 
> > See the github issue
> > https://github.com/linux-audit/audit-kernel/issues/67
> > 
> > Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
> > ---
> >  arch/alpha/kernel/audit.c          | 2 ++
> >  arch/ia64/kernel/audit.c           | 2 ++
> >  arch/parisc/kernel/audit.c         | 2 ++
> >  arch/parisc/kernel/compat_audit.c  | 2 ++
> >  arch/powerpc/kernel/audit.c        | 2 ++
> >  arch/powerpc/kernel/compat_audit.c | 2 ++
> >  arch/s390/kernel/audit.c           | 2 ++
> >  arch/s390/kernel/compat_audit.c    | 2 ++
> >  arch/sparc/kernel/audit.c          | 2 ++
> >  arch/sparc/kernel/compat_audit.c   | 2 ++
> >  arch/x86/ia32/audit.c              | 2 ++
> >  arch/x86/kernel/audit_64.c         | 2 ++
> >  kernel/auditsc.c                   | 3 +++
> >  lib/audit.c                        | 4 ++++
> >  lib/compat_audit.c                 | 4 ++++
> >  15 files changed, 35 insertions(+)
> > 
> > diff --git a/arch/alpha/kernel/audit.c b/arch/alpha/kernel/audit.c
> > index 96a9d18ff4c4..06a911b685d1 100644
> > --- a/arch/alpha/kernel/audit.c
> > +++ b/arch/alpha/kernel/audit.c
> > @@ -42,6 +42,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 3;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/ia64/kernel/audit.c b/arch/ia64/kernel/audit.c
> > index 5192ca899fe6..5eaa888c8fd3 100644
> > --- a/arch/ia64/kernel/audit.c
> > +++ b/arch/ia64/kernel/audit.c
> > @@ -43,6 +43,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 3;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/parisc/kernel/audit.c b/arch/parisc/kernel/audit.c
> > index 9eb47b2225d2..fc721a7727ba 100644
> > --- a/arch/parisc/kernel/audit.c
> > +++ b/arch/parisc/kernel/audit.c
> > @@ -52,6 +52,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 3;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/parisc/kernel/compat_audit.c b/arch/parisc/kernel/compat_audit.c
> > index 20c39c9d86a9..fc6d35918c44 100644
> > --- a/arch/parisc/kernel/compat_audit.c
> > +++ b/arch/parisc/kernel/compat_audit.c
> > @@ -35,6 +35,8 @@ int parisc32_classify_syscall(unsigned syscall)
> >  		return 3;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/powerpc/kernel/audit.c b/arch/powerpc/kernel/audit.c
> > index a2dddd7f3d09..8f32700b0baa 100644
> > --- a/arch/powerpc/kernel/audit.c
> > +++ b/arch/powerpc/kernel/audit.c
> > @@ -54,6 +54,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/powerpc/kernel/compat_audit.c b/arch/powerpc/kernel/compat_audit.c
> > index 55c6ccda0a85..ebe45534b1c9 100644
> > --- a/arch/powerpc/kernel/compat_audit.c
> > +++ b/arch/powerpc/kernel/compat_audit.c
> > @@ -38,6 +38,8 @@ int ppc32_classify_syscall(unsigned syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/s390/kernel/audit.c b/arch/s390/kernel/audit.c
> > index d395c6c9944c..d964cb94cfaf 100644
> > --- a/arch/s390/kernel/audit.c
> > +++ b/arch/s390/kernel/audit.c
> > @@ -54,6 +54,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/s390/kernel/compat_audit.c b/arch/s390/kernel/compat_audit.c
> > index 444fb1f66944..f7b32933ce0e 100644
> > --- a/arch/s390/kernel/compat_audit.c
> > +++ b/arch/s390/kernel/compat_audit.c
> > @@ -39,6 +39,8 @@ int s390_classify_syscall(unsigned syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/sparc/kernel/audit.c b/arch/sparc/kernel/audit.c
> > index a6e91bf34d48..b6dcca9c6520 100644
> > --- a/arch/sparc/kernel/audit.c
> > +++ b/arch/sparc/kernel/audit.c
> > @@ -55,6 +55,8 @@ int audit_classify_syscall(int abi, unsigned int syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/sparc/kernel/compat_audit.c b/arch/sparc/kernel/compat_audit.c
> > index 10eeb4f15b20..d2652a1083ad 100644
> > --- a/arch/sparc/kernel/compat_audit.c
> > +++ b/arch/sparc/kernel/compat_audit.c
> > @@ -39,6 +39,8 @@ int sparc32_classify_syscall(unsigned int syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/x86/ia32/audit.c b/arch/x86/ia32/audit.c
> > index 6efe6cb3768a..57a02ade5503 100644
> > --- a/arch/x86/ia32/audit.c
> > +++ b/arch/x86/ia32/audit.c
> > @@ -39,6 +39,8 @@ int ia32_classify_syscall(unsigned syscall)
> >  	case __NR_execve:
> >  	case __NR_execveat:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/x86/kernel/audit_64.c b/arch/x86/kernel/audit_64.c
> > index 83d9cad4e68b..39de1e021258 100644
> > --- a/arch/x86/kernel/audit_64.c
> > +++ b/arch/x86/kernel/audit_64.c
> > @@ -53,6 +53,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  	case __NR_execve:
> >  	case __NR_execveat:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> > index 8bb9ac84d2fb..f5616e70d129 100644
> > --- a/kernel/auditsc.c
> > +++ b/kernel/auditsc.c
> > @@ -76,6 +76,7 @@
> >  #include <linux/fsnotify_backend.h>
> >  #include <uapi/linux/limits.h>
> >  #include <uapi/linux/netfilter/nf_tables.h>
> > +#include <uapi/linux/openat2.h>
> >  
> >  #include "audit.h"
> >  
> > @@ -195,6 +196,8 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
> >  		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
> >  	case 5: /* execve */
> >  		return mask & AUDIT_PERM_EXEC;
> > +	case 6: /* openat2 */
> > +		return mask & ACC_MODE((u32)((struct open_how *)ctx->argv[2])->flags);
> 
> That looks a bit dodgy. Maybe sm like the below would be a bit better?
> 
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 47fb48f42c93..531e882a5096 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -159,6 +159,7 @@ static const struct audit_nfcfgop_tab audit_nfcfgs[] = {
> 
>  static int audit_match_perm(struct audit_context *ctx, int mask)
>  {
> +       struct open_how *openat2;
>         unsigned n;
>         if (unlikely(!ctx))
>                 return 0;
> @@ -195,6 +196,12 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
>                 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
>         case 5: /* execve */
>                 return mask & AUDIT_PERM_EXEC;
> +       case 6: /* openat2 */
> +               openat2 = ctx->argv[2];
> +               if (upper_32_bits(openat2->flags))
> +                       pr_warn("Some sensible warning about unknown flags");
> +
> +               return mask & ACC_MODE(lower_32_bits(openat2->flags));
>         default:
>                 return 0;
>         }
> 
> (Ideally we'd probably notice at build-time that we've got flags
> exceeding 32bits. Could probably easily been done by exposing an all
> flags macro somewhere and then we can place a BUILD_BUG_ON() or sm into
> such places.)

And one more comment, why return a hard-coded integer from all of these
architectures instead of introducing an enum in a central place with
proper names idk:

enum audit_match_perm_t {
	.
	.
	.
	AUDIT_MATCH_PERM_EXECVE = 5,
	AUDIT_MATCH_PERM_OPENAT2 = 6,
	.
	.
	.
}

Then you can drop these hard-coded comments too and it's way less
brittle overall.

Christian
Richard Guy Briggs March 18, 2021, 12:03 p.m. UTC | #3
On 2021-03-18 11:52, Christian Brauner wrote:
> On Thu, Mar 18, 2021 at 11:48:45AM +0100, Christian Brauner wrote:
> > On Wed, Mar 17, 2021 at 09:47:17PM -0400, Richard Guy Briggs wrote:
> > > The openat2(2) syscall was added in kernel v5.6 with commit fddb5d430ad9
> > > ("open: introduce openat2(2) syscall")
> > > Add the openat2(2) syscall to the audit syscall classifier.
> > > See the github issue
> > > https://github.com/linux-audit/audit-kernel/issues/67
> > > Signed-off-by: Richard Guy Briggs <rgb@redhat.com>

...

> And one more comment, why return a hard-coded integer from all of these
> architectures instead of introducing an enum in a central place with
> proper names idk:

Oh, believe me, I tried hard to do that because I really don't like
hard-coded magic values, but for expediency I continued the same
approach until I could sort out the header file mess.  There was an
extra preparatory patch (attached) in this patchset with a different
audit syscall perms patch (also attached).  By including "#include
<linux/audit.h>" in each of the compat source files there were warnings
of redefinitions of every __NR_* syscall number.  The easiest way to get
rid of it would have been to pull the new AUDITSC_* definitions into a
new <linux/auditsc.h> file and include that from <linux/audit.h> and
each of the arch/*/*/*audit.c (and lib/*audit.c) files.

> enum audit_match_perm_t {
> 	.
> 	.
> 	.
> 	AUDIT_MATCH_PERM_EXECVE = 5,
> 	AUDIT_MATCH_PERM_OPENAT2 = 6,
> 	.
> 	.
> 	.
> }
> 
> Then you can drop these hard-coded comments too and it's way less
> brittle overall.

Totally agree.

> Christian

- RGB

--
Richard Guy Briggs <rgb@redhat.com>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
Voice: +1.647.777.2635, Internal: (81) 32635
From 599ae48091296a3ad3eb4259e7af39cdf0f743c7 Mon Sep 17 00:00:00 2001
Message-Id: <599ae48091296a3ad3eb4259e7af39cdf0f743c7.1616067847.git.rgb@redhat.com>
In-Reply-To: <cover.1616067847.git.rgb@redhat.com>
References: <cover.1616067847.git.rgb@redhat.com>
From: Richard Guy Briggs <rgb@redhat.com>
Date: Fri, 22 Jan 2021 16:27:42 -0500
Subject: [PATCH 1/3] audit: replace magic audit syscall class numbers with
 macros

Replace the magic numbers used to indicate audit syscall classes with macros.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
---
 arch/alpha/kernel/audit.c          |  8 ++++----
 arch/ia64/kernel/audit.c           |  8 ++++----
 arch/parisc/kernel/audit.c         |  8 ++++----
 arch/parisc/kernel/compat_audit.c  |  9 +++++----
 arch/powerpc/kernel/audit.c        | 10 +++++-----
 arch/powerpc/kernel/compat_audit.c | 11 ++++++-----
 arch/s390/kernel/audit.c           | 10 +++++-----
 arch/s390/kernel/compat_audit.c    | 11 ++++++-----
 arch/sparc/kernel/audit.c          | 10 +++++-----
 arch/sparc/kernel/compat_audit.c   | 11 ++++++-----
 arch/x86/ia32/audit.c              | 11 ++++++-----
 arch/x86/kernel/audit_64.c         |  8 ++++----
 include/linux/audit.h              |  7 +++++++
 kernel/auditsc.c                   | 12 ++++++------
 lib/audit.c                        | 10 +++++-----
 lib/compat_audit.c                 | 11 ++++++-----
 16 files changed, 84 insertions(+), 71 deletions(-)

diff --git a/arch/alpha/kernel/audit.c b/arch/alpha/kernel/audit.c
index 96a9d18ff4c4..81cbd804e375 100644
--- a/arch/alpha/kernel/audit.c
+++ b/arch/alpha/kernel/audit.c
@@ -37,13 +37,13 @@ int audit_classify_syscall(int abi, unsigned syscall)
 {
 	switch(syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 0;
+		return AUDITSC_NATIVE;
 	}
 }
 
diff --git a/arch/ia64/kernel/audit.c b/arch/ia64/kernel/audit.c
index 5192ca899fe6..dba6a74c9ab3 100644
--- a/arch/ia64/kernel/audit.c
+++ b/arch/ia64/kernel/audit.c
@@ -38,13 +38,13 @@ int audit_classify_syscall(int abi, unsigned syscall)
 {
 	switch(syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 0;
+		return AUDITSC_NATIVE;
 	}
 }
 
diff --git a/arch/parisc/kernel/audit.c b/arch/parisc/kernel/audit.c
index 9eb47b2225d2..14244e83db75 100644
--- a/arch/parisc/kernel/audit.c
+++ b/arch/parisc/kernel/audit.c
@@ -47,13 +47,13 @@ int audit_classify_syscall(int abi, unsigned syscall)
 #endif
 	switch (syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 0;
+		return AUDITSC_NATIVE;
 	}
 }
 
diff --git a/arch/parisc/kernel/compat_audit.c b/arch/parisc/kernel/compat_audit.c
index 20c39c9d86a9..68102807aba7 100644
--- a/arch/parisc/kernel/compat_audit.c
+++ b/arch/parisc/kernel/compat_audit.c
@@ -1,4 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
+#include <linux/audit.h>
 #include <asm/unistd.h>
 
 unsigned int parisc32_dir_class[] = {
@@ -30,12 +31,12 @@ int parisc32_classify_syscall(unsigned syscall)
 {
 	switch (syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 1;
+		return AUDITSC_COMPAT;
 	}
 }
diff --git a/arch/powerpc/kernel/audit.c b/arch/powerpc/kernel/audit.c
index a2dddd7f3d09..6eb18ef77dff 100644
--- a/arch/powerpc/kernel/audit.c
+++ b/arch/powerpc/kernel/audit.c
@@ -47,15 +47,15 @@ int audit_classify_syscall(int abi, unsigned syscall)
 #endif
 	switch(syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_socketcall:
-		return 4;
+		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 0;
+		return AUDITSC_NATIVE;
 	}
 }
 
diff --git a/arch/powerpc/kernel/compat_audit.c b/arch/powerpc/kernel/compat_audit.c
index 55c6ccda0a85..b3fd2d43bfff 100644
--- a/arch/powerpc/kernel/compat_audit.c
+++ b/arch/powerpc/kernel/compat_audit.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 #undef __powerpc64__
+#include <linux/audit.h>
 #include <asm/unistd.h>
 
 unsigned ppc32_dir_class[] = {
@@ -31,14 +32,14 @@ int ppc32_classify_syscall(unsigned syscall)
 {
 	switch(syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_socketcall:
-		return 4;
+		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 1;
+		return AUDITSC_COMPAT;
 	}
 }
diff --git a/arch/s390/kernel/audit.c b/arch/s390/kernel/audit.c
index d395c6c9944c..7e331e1831d4 100644
--- a/arch/s390/kernel/audit.c
+++ b/arch/s390/kernel/audit.c
@@ -47,15 +47,15 @@ int audit_classify_syscall(int abi, unsigned syscall)
 #endif
 	switch(syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_socketcall:
-		return 4;
+		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 0;
+		return AUDITSC_NATIVE;
 	}
 }
 
diff --git a/arch/s390/kernel/compat_audit.c b/arch/s390/kernel/compat_audit.c
index 444fb1f66944..704d04cfd9dd 100644
--- a/arch/s390/kernel/compat_audit.c
+++ b/arch/s390/kernel/compat_audit.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 #undef __s390x__
+#include <linux/audit.h>
 #include <asm/unistd.h>
 #include "audit.h"
 
@@ -32,14 +33,14 @@ int s390_classify_syscall(unsigned syscall)
 {
 	switch(syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_socketcall:
-		return 4;
+		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 1;
+		return AUDITSC_COMPAT;
 	}
 }
diff --git a/arch/sparc/kernel/audit.c b/arch/sparc/kernel/audit.c
index a6e91bf34d48..50fab35bdaba 100644
--- a/arch/sparc/kernel/audit.c
+++ b/arch/sparc/kernel/audit.c
@@ -48,15 +48,15 @@ int audit_classify_syscall(int abi, unsigned int syscall)
 #endif
 	switch(syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_socketcall:
-		return 4;
+		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 0;
+		return AUDITSC_NATIVE;
 	}
 }
 
diff --git a/arch/sparc/kernel/compat_audit.c b/arch/sparc/kernel/compat_audit.c
index 10eeb4f15b20..4c2f9a4ee845 100644
--- a/arch/sparc/kernel/compat_audit.c
+++ b/arch/sparc/kernel/compat_audit.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 #define __32bit_syscall_numbers__
+#include <linux/audit.h>
 #include <asm/unistd.h>
 #include "kernel.h"
 
@@ -32,14 +33,14 @@ int sparc32_classify_syscall(unsigned int syscall)
 {
 	switch(syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_socketcall:
-		return 4;
+		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 1;
+		return AUDITSC_COMPAT;
 	}
 }
diff --git a/arch/x86/ia32/audit.c b/arch/x86/ia32/audit.c
index 6efe6cb3768a..0798a6b66314 100644
--- a/arch/x86/ia32/audit.c
+++ b/arch/x86/ia32/audit.c
@@ -1,4 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
+#include <linux/audit.h>
 #include <asm/unistd_32.h>
 #include <asm/audit.h>
 
@@ -31,15 +32,15 @@ int ia32_classify_syscall(unsigned syscall)
 {
 	switch (syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_socketcall:
-		return 4;
+		return AUDITSC_SOCKETCALL;
 	case __NR_execve:
 	case __NR_execveat:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 1;
+		return AUDITSC_COMPAT;
 	}
 }
diff --git a/arch/x86/kernel/audit_64.c b/arch/x86/kernel/audit_64.c
index 83d9cad4e68b..2a6cc9c9c881 100644
--- a/arch/x86/kernel/audit_64.c
+++ b/arch/x86/kernel/audit_64.c
@@ -47,14 +47,14 @@ int audit_classify_syscall(int abi, unsigned syscall)
 #endif
 	switch(syscall) {
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 	case __NR_execve:
 	case __NR_execveat:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 0;
+		return AUDITSC_NATIVE;
 	}
 }
 
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 82b7c1116a85..bcf0150b1528 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -120,6 +120,13 @@ enum audit_nfcfgop {
 
 extern int is_audit_feature_set(int which);
 
+#define AUDITSC_NATIVE		0
+#define AUDITSC_COMPAT		1
+#define AUDITSC_OPEN		2
+#define AUDITSC_OPENAT		3
+#define AUDITSC_SOCKETCALL	4
+#define AUDITSC_EXECVE		5
+
 extern int __init audit_register_class(int class, unsigned *list);
 extern int audit_classify_syscall(int abi, unsigned syscall);
 extern int audit_classify_arch(int arch);
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 71ead2969eeb..dddea985f23e 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -165,7 +165,7 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
 	n = ctx->major;
 
 	switch (audit_classify_syscall(ctx->arch, n)) {
-	case 0:	/* native */
+	case AUDITSC_NATIVE:
 		if ((mask & AUDIT_PERM_WRITE) &&
 		     audit_match_class(AUDIT_CLASS_WRITE, n))
 			return 1;
@@ -176,7 +176,7 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
 		     audit_match_class(AUDIT_CLASS_CHATTR, n))
 			return 1;
 		return 0;
-	case 1: /* 32bit on biarch */
+	case AUDITSC_COMPAT: /* 32bit on biarch */
 		if ((mask & AUDIT_PERM_WRITE) &&
 		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
 			return 1;
@@ -187,13 +187,13 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
 		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
 			return 1;
 		return 0;
-	case 2: /* open */
+	case AUDITSC_OPEN:
 		return mask & ACC_MODE(ctx->argv[1]);
-	case 3: /* openat */
+	case AUDITSC_OPENAT:
 		return mask & ACC_MODE(ctx->argv[2]);
-	case 4: /* socketcall */
+	case AUDITSC_SOCKETCALL:
 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
-	case 5: /* execve */
+	case AUDITSC_EXECVE:
 		return mask & AUDIT_PERM_EXEC;
 	default:
 		return 0;
diff --git a/lib/audit.c b/lib/audit.c
index 5004bff928a7..3ec1a94d8d64 100644
--- a/lib/audit.c
+++ b/lib/audit.c
@@ -45,23 +45,23 @@ int audit_classify_syscall(int abi, unsigned syscall)
 	switch(syscall) {
 #ifdef __NR_open
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 #endif
 #ifdef __NR_openat
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 #endif
 #ifdef __NR_socketcall
 	case __NR_socketcall:
-		return 4;
+		return AUDITSC_SOCKETCALL;
 #endif
 #ifdef __NR_execveat
 	case __NR_execveat:
 #endif
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 0;
+		return AUDITSC_NATIVE;
 	}
 }
 
diff --git a/lib/compat_audit.c b/lib/compat_audit.c
index 77eabad69b4a..528dafa2c2bb 100644
--- a/lib/compat_audit.c
+++ b/lib/compat_audit.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/audit.h>
 #include <asm/unistd32.h>
 
 unsigned compat_dir_class[] = {
@@ -33,19 +34,19 @@ int audit_classify_compat_syscall(int abi, unsigned syscall)
 	switch (syscall) {
 #ifdef __NR_open
 	case __NR_open:
-		return 2;
+		return AUDITSC_OPEN;
 #endif
 #ifdef __NR_openat
 	case __NR_openat:
-		return 3;
+		return AUDITSC_OPENAT;
 #endif
 #ifdef __NR_socketcall
 	case __NR_socketcall:
-		return 4;
+		return AUDITSC_SOCKETCALL;
 #endif
 	case __NR_execve:
-		return 5;
+		return AUDITSC_EXECVE;
 	default:
-		return 1;
+		return AUDITSC_COMPAT;
 	}
 }
Richard Guy Briggs March 18, 2021, 12:08 p.m. UTC | #4
On 2021-03-18 11:48, Christian Brauner wrote:
> [+Cc Aleksa, the author of openat2()]

Ah!  Thanks for pulling in Aleksa.  I thought I caught everyone...

> and a comment below. :)

Same...

> On Wed, Mar 17, 2021 at 09:47:17PM -0400, Richard Guy Briggs wrote:
> > The openat2(2) syscall was added in kernel v5.6 with commit fddb5d430ad9
> > ("open: introduce openat2(2) syscall")
> > 
> > Add the openat2(2) syscall to the audit syscall classifier.
> > 
> > See the github issue
> > https://github.com/linux-audit/audit-kernel/issues/67
> > 
> > Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
> > ---
> >  arch/alpha/kernel/audit.c          | 2 ++
> >  arch/ia64/kernel/audit.c           | 2 ++
> >  arch/parisc/kernel/audit.c         | 2 ++
> >  arch/parisc/kernel/compat_audit.c  | 2 ++
> >  arch/powerpc/kernel/audit.c        | 2 ++
> >  arch/powerpc/kernel/compat_audit.c | 2 ++
> >  arch/s390/kernel/audit.c           | 2 ++
> >  arch/s390/kernel/compat_audit.c    | 2 ++
> >  arch/sparc/kernel/audit.c          | 2 ++
> >  arch/sparc/kernel/compat_audit.c   | 2 ++
> >  arch/x86/ia32/audit.c              | 2 ++
> >  arch/x86/kernel/audit_64.c         | 2 ++
> >  kernel/auditsc.c                   | 3 +++
> >  lib/audit.c                        | 4 ++++
> >  lib/compat_audit.c                 | 4 ++++
> >  15 files changed, 35 insertions(+)
> > 
> > diff --git a/arch/alpha/kernel/audit.c b/arch/alpha/kernel/audit.c
> > index 96a9d18ff4c4..06a911b685d1 100644
> > --- a/arch/alpha/kernel/audit.c
> > +++ b/arch/alpha/kernel/audit.c
> > @@ -42,6 +42,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 3;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/ia64/kernel/audit.c b/arch/ia64/kernel/audit.c
> > index 5192ca899fe6..5eaa888c8fd3 100644
> > --- a/arch/ia64/kernel/audit.c
> > +++ b/arch/ia64/kernel/audit.c
> > @@ -43,6 +43,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 3;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/parisc/kernel/audit.c b/arch/parisc/kernel/audit.c
> > index 9eb47b2225d2..fc721a7727ba 100644
> > --- a/arch/parisc/kernel/audit.c
> > +++ b/arch/parisc/kernel/audit.c
> > @@ -52,6 +52,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 3;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/parisc/kernel/compat_audit.c b/arch/parisc/kernel/compat_audit.c
> > index 20c39c9d86a9..fc6d35918c44 100644
> > --- a/arch/parisc/kernel/compat_audit.c
> > +++ b/arch/parisc/kernel/compat_audit.c
> > @@ -35,6 +35,8 @@ int parisc32_classify_syscall(unsigned syscall)
> >  		return 3;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/powerpc/kernel/audit.c b/arch/powerpc/kernel/audit.c
> > index a2dddd7f3d09..8f32700b0baa 100644
> > --- a/arch/powerpc/kernel/audit.c
> > +++ b/arch/powerpc/kernel/audit.c
> > @@ -54,6 +54,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/powerpc/kernel/compat_audit.c b/arch/powerpc/kernel/compat_audit.c
> > index 55c6ccda0a85..ebe45534b1c9 100644
> > --- a/arch/powerpc/kernel/compat_audit.c
> > +++ b/arch/powerpc/kernel/compat_audit.c
> > @@ -38,6 +38,8 @@ int ppc32_classify_syscall(unsigned syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/s390/kernel/audit.c b/arch/s390/kernel/audit.c
> > index d395c6c9944c..d964cb94cfaf 100644
> > --- a/arch/s390/kernel/audit.c
> > +++ b/arch/s390/kernel/audit.c
> > @@ -54,6 +54,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/s390/kernel/compat_audit.c b/arch/s390/kernel/compat_audit.c
> > index 444fb1f66944..f7b32933ce0e 100644
> > --- a/arch/s390/kernel/compat_audit.c
> > +++ b/arch/s390/kernel/compat_audit.c
> > @@ -39,6 +39,8 @@ int s390_classify_syscall(unsigned syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/sparc/kernel/audit.c b/arch/sparc/kernel/audit.c
> > index a6e91bf34d48..b6dcca9c6520 100644
> > --- a/arch/sparc/kernel/audit.c
> > +++ b/arch/sparc/kernel/audit.c
> > @@ -55,6 +55,8 @@ int audit_classify_syscall(int abi, unsigned int syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/arch/sparc/kernel/compat_audit.c b/arch/sparc/kernel/compat_audit.c
> > index 10eeb4f15b20..d2652a1083ad 100644
> > --- a/arch/sparc/kernel/compat_audit.c
> > +++ b/arch/sparc/kernel/compat_audit.c
> > @@ -39,6 +39,8 @@ int sparc32_classify_syscall(unsigned int syscall)
> >  		return 4;
> >  	case __NR_execve:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/x86/ia32/audit.c b/arch/x86/ia32/audit.c
> > index 6efe6cb3768a..57a02ade5503 100644
> > --- a/arch/x86/ia32/audit.c
> > +++ b/arch/x86/ia32/audit.c
> > @@ -39,6 +39,8 @@ int ia32_classify_syscall(unsigned syscall)
> >  	case __NR_execve:
> >  	case __NR_execveat:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 1;
> >  	}
> > diff --git a/arch/x86/kernel/audit_64.c b/arch/x86/kernel/audit_64.c
> > index 83d9cad4e68b..39de1e021258 100644
> > --- a/arch/x86/kernel/audit_64.c
> > +++ b/arch/x86/kernel/audit_64.c
> > @@ -53,6 +53,8 @@ int audit_classify_syscall(int abi, unsigned syscall)
> >  	case __NR_execve:
> >  	case __NR_execveat:
> >  		return 5;
> > +	case __NR_openat2:
> > +		return 6;
> >  	default:
> >  		return 0;
> >  	}
> > diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> > index 8bb9ac84d2fb..f5616e70d129 100644
> > --- a/kernel/auditsc.c
> > +++ b/kernel/auditsc.c
> > @@ -76,6 +76,7 @@
> >  #include <linux/fsnotify_backend.h>
> >  #include <uapi/linux/limits.h>
> >  #include <uapi/linux/netfilter/nf_tables.h>
> > +#include <uapi/linux/openat2.h>
> >  
> >  #include "audit.h"
> >  
> > @@ -195,6 +196,8 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
> >  		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
> >  	case 5: /* execve */
> >  		return mask & AUDIT_PERM_EXEC;
> > +	case 6: /* openat2 */
> > +		return mask & ACC_MODE((u32)((struct open_how *)ctx->argv[2])->flags);
> 
> That looks a bit dodgy. Maybe sm like the below would be a bit better?

Ah, ok, fair enough, since original flags use a u32 and this was picked
as u64 for alignment.  It was just occurring to me last night that I
might have the dubious honour of being the first usage of 0%llo format
specifier in the kernel...  ;-)

> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 47fb48f42c93..531e882a5096 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -159,6 +159,7 @@ static const struct audit_nfcfgop_tab audit_nfcfgs[] = {
> 
>  static int audit_match_perm(struct audit_context *ctx, int mask)
>  {
> +       struct open_how *openat2;
>         unsigned n;
>         if (unlikely(!ctx))
>                 return 0;
> @@ -195,6 +196,12 @@ static int audit_match_perm(struct audit_context *ctx, int mask)
>                 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
>         case 5: /* execve */
>                 return mask & AUDIT_PERM_EXEC;
> +       case 6: /* openat2 */
> +               openat2 = ctx->argv[2];
> +               if (upper_32_bits(openat2->flags))
> +                       pr_warn("Some sensible warning about unknown flags");
> +
> +               return mask & ACC_MODE(lower_32_bits(openat2->flags));
>         default:
>                 return 0;
>         }
> 
> (Ideally we'd probably notice at build-time that we've got flags
> exceeding 32bits. Could probably easily been done by exposing an all
> flags macro somewhere and then we can place a BUILD_BUG_ON() or sm into
> such places.)
> 
> Christian

- RGB

--
Richard Guy Briggs <rgb@redhat.com>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
Voice: +1.647.777.2635, Internal: (81) 32635
diff mbox series

Patch

diff --git a/arch/alpha/kernel/audit.c b/arch/alpha/kernel/audit.c
index 96a9d18ff4c4..06a911b685d1 100644
--- a/arch/alpha/kernel/audit.c
+++ b/arch/alpha/kernel/audit.c
@@ -42,6 +42,8 @@  int audit_classify_syscall(int abi, unsigned syscall)
 		return 3;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 0;
 	}
diff --git a/arch/ia64/kernel/audit.c b/arch/ia64/kernel/audit.c
index 5192ca899fe6..5eaa888c8fd3 100644
--- a/arch/ia64/kernel/audit.c
+++ b/arch/ia64/kernel/audit.c
@@ -43,6 +43,8 @@  int audit_classify_syscall(int abi, unsigned syscall)
 		return 3;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 0;
 	}
diff --git a/arch/parisc/kernel/audit.c b/arch/parisc/kernel/audit.c
index 9eb47b2225d2..fc721a7727ba 100644
--- a/arch/parisc/kernel/audit.c
+++ b/arch/parisc/kernel/audit.c
@@ -52,6 +52,8 @@  int audit_classify_syscall(int abi, unsigned syscall)
 		return 3;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 0;
 	}
diff --git a/arch/parisc/kernel/compat_audit.c b/arch/parisc/kernel/compat_audit.c
index 20c39c9d86a9..fc6d35918c44 100644
--- a/arch/parisc/kernel/compat_audit.c
+++ b/arch/parisc/kernel/compat_audit.c
@@ -35,6 +35,8 @@  int parisc32_classify_syscall(unsigned syscall)
 		return 3;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 1;
 	}
diff --git a/arch/powerpc/kernel/audit.c b/arch/powerpc/kernel/audit.c
index a2dddd7f3d09..8f32700b0baa 100644
--- a/arch/powerpc/kernel/audit.c
+++ b/arch/powerpc/kernel/audit.c
@@ -54,6 +54,8 @@  int audit_classify_syscall(int abi, unsigned syscall)
 		return 4;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 0;
 	}
diff --git a/arch/powerpc/kernel/compat_audit.c b/arch/powerpc/kernel/compat_audit.c
index 55c6ccda0a85..ebe45534b1c9 100644
--- a/arch/powerpc/kernel/compat_audit.c
+++ b/arch/powerpc/kernel/compat_audit.c
@@ -38,6 +38,8 @@  int ppc32_classify_syscall(unsigned syscall)
 		return 4;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 1;
 	}
diff --git a/arch/s390/kernel/audit.c b/arch/s390/kernel/audit.c
index d395c6c9944c..d964cb94cfaf 100644
--- a/arch/s390/kernel/audit.c
+++ b/arch/s390/kernel/audit.c
@@ -54,6 +54,8 @@  int audit_classify_syscall(int abi, unsigned syscall)
 		return 4;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 0;
 	}
diff --git a/arch/s390/kernel/compat_audit.c b/arch/s390/kernel/compat_audit.c
index 444fb1f66944..f7b32933ce0e 100644
--- a/arch/s390/kernel/compat_audit.c
+++ b/arch/s390/kernel/compat_audit.c
@@ -39,6 +39,8 @@  int s390_classify_syscall(unsigned syscall)
 		return 4;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 1;
 	}
diff --git a/arch/sparc/kernel/audit.c b/arch/sparc/kernel/audit.c
index a6e91bf34d48..b6dcca9c6520 100644
--- a/arch/sparc/kernel/audit.c
+++ b/arch/sparc/kernel/audit.c
@@ -55,6 +55,8 @@  int audit_classify_syscall(int abi, unsigned int syscall)
 		return 4;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 0;
 	}
diff --git a/arch/sparc/kernel/compat_audit.c b/arch/sparc/kernel/compat_audit.c
index 10eeb4f15b20..d2652a1083ad 100644
--- a/arch/sparc/kernel/compat_audit.c
+++ b/arch/sparc/kernel/compat_audit.c
@@ -39,6 +39,8 @@  int sparc32_classify_syscall(unsigned int syscall)
 		return 4;
 	case __NR_execve:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 1;
 	}
diff --git a/arch/x86/ia32/audit.c b/arch/x86/ia32/audit.c
index 6efe6cb3768a..57a02ade5503 100644
--- a/arch/x86/ia32/audit.c
+++ b/arch/x86/ia32/audit.c
@@ -39,6 +39,8 @@  int ia32_classify_syscall(unsigned syscall)
 	case __NR_execve:
 	case __NR_execveat:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 1;
 	}
diff --git a/arch/x86/kernel/audit_64.c b/arch/x86/kernel/audit_64.c
index 83d9cad4e68b..39de1e021258 100644
--- a/arch/x86/kernel/audit_64.c
+++ b/arch/x86/kernel/audit_64.c
@@ -53,6 +53,8 @@  int audit_classify_syscall(int abi, unsigned syscall)
 	case __NR_execve:
 	case __NR_execveat:
 		return 5;
+	case __NR_openat2:
+		return 6;
 	default:
 		return 0;
 	}
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 8bb9ac84d2fb..f5616e70d129 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -76,6 +76,7 @@ 
 #include <linux/fsnotify_backend.h>
 #include <uapi/linux/limits.h>
 #include <uapi/linux/netfilter/nf_tables.h>
+#include <uapi/linux/openat2.h>
 
 #include "audit.h"
 
@@ -195,6 +196,8 @@  static int audit_match_perm(struct audit_context *ctx, int mask)
 		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
 	case 5: /* execve */
 		return mask & AUDIT_PERM_EXEC;
+	case 6: /* openat2 */
+		return mask & ACC_MODE((u32)((struct open_how *)ctx->argv[2])->flags);
 	default:
 		return 0;
 	}
diff --git a/lib/audit.c b/lib/audit.c
index 5004bff928a7..8f030b9a2d10 100644
--- a/lib/audit.c
+++ b/lib/audit.c
@@ -60,6 +60,10 @@  int audit_classify_syscall(int abi, unsigned syscall)
 #endif
 	case __NR_execve:
 		return 5;
+#ifdef __NR_openat2
+	case __NR_openat2:
+		return 6;
+#endif
 	default:
 		return 0;
 	}
diff --git a/lib/compat_audit.c b/lib/compat_audit.c
index 77eabad69b4a..8aff0d0d9ba0 100644
--- a/lib/compat_audit.c
+++ b/lib/compat_audit.c
@@ -45,6 +45,10 @@  int audit_classify_compat_syscall(int abi, unsigned syscall)
 #endif
 	case __NR_execve:
 		return 5;
+#ifdef __NR_openat2
+	case __NR_openat2:
+		return 6;
+#endif
 	default:
 		return 1;
 	}