[PATCH] audit: allow other filter list types for AUDIT_EXE

[Richard Guy Briggs]

On 2018-04-25 15:06, Ondrej Mosnacek wrote:
> This patch removes the restriction of the AUDIT_EXE field to only
> SYSCALL filter and teaches audit_filter to recognize this field.
> 
> This makes it possible to write rule lists such as:
> 
>     auditctl -a exit,always [some general rule]
>     # Filter out events with executable name /bin/exe1 or /bin/exe2:
>     auditctl -a exclude,always -F exe=/bin/exe1
>     auditctl -a exclude,always -F exe=/bin/exe2
> 
> See: https://github.com/linux-audit/audit-kernel/issues/54
> 
> Signed-off-by: Ondrej Mosnacek <omosnace at redhat.com>
> ---
>  kernel/auditfilter.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
> index a0c5a3ec6e60..8c9abbf20d42 100644
> --- a/kernel/auditfilter.c
> +++ b/kernel/auditfilter.c
> @@ -428,8 +428,6 @@ static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
>  	case AUDIT_EXE:
>  		if (f->op != Audit_not_equal && f->op != Audit_equal)
>  			return -EINVAL;
> -		if (entry->rule.listnr != AUDIT_FILTER_EXIT)
> -			return -EINVAL;

This looks right since the FS filter will throw its own error in
higher in that function.  (The ENTRY and WATCH filters are gone.)

>  		break;
>  	}
>  	return 0;
> @@ -1362,6 +1360,11 @@ int audit_filter(int msgtype, unsigned int listtype)
>  							f->type, f->op, f->lsm_rule, NULL);
>  				}
>  				break;
> +			case AUDIT_EXE:
> +				result = audit_exe_compare(current, e->rule.exe);
> +				if (f->op == Audit_not_equal)
> +					result = !result;
> +				break;
>  			default:
>  				goto unlock_and_return;
>  			}

Reviewed-by: Richard Guy Briggs <rgb at redhat.com>

- RGB

--
Richard Guy Briggs <rgb at 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