From 5141c6967fd9c607f580ccd53be0a8d46a5f0685 Mon Sep 17 00:00:00 2001 From: Stephen Smalley Date: Wed, 17 Jun 2020 15:23:09 -0400 Subject: [PATCH] selinux: log error messages on required process class / permissions In general SELinux no longer treats undefined object classes or permissions in the policy as a fatal error, instead handling them in accordance with handle_unknown. However, the process class and process transition and dyntransition permissions are still required to be defined due to dependencies on these definitions for default labeling behaviors, role and range transitions in older policy versions that lack an explicit class field, and role allow checking. Log error messages in these cases since otherwise the policy load will fail silently with no indication to the user as to the underlying cause. While here, fix the checking for process transition / dyntransition so that omitting either permission is handled as an error; both are needed in order to ensure that role allow checking is consistently applied. Reported-by: bauen1 Signed-off-by: Stephen Smalley Signed-off-by: Paul Moore --- security/selinux/ss/policydb.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c index 98f343005d6b5..6f81152248524 100644 --- a/security/selinux/ss/policydb.c +++ b/security/selinux/ss/policydb.c @@ -2376,7 +2376,7 @@ int policydb_read(struct policydb *p, void *fp) struct role_trans_datum *rtd = NULL; int i, j, rc; __le32 buf[4]; - u32 len, nprim, nel; + u32 len, nprim, nel, perm; char *policydb_str; struct policydb_compat_info *info; @@ -2519,8 +2519,10 @@ int policydb_read(struct policydb *p, void *fp) rc = -EINVAL; p->process_class = string_to_security_class(p, "process"); - if (!p->process_class) + if (!p->process_class) { + pr_err("SELinux: process class is required, not defined in policy\n"); goto bad; + } rc = avtab_read(&p->te_avtab, fp, p); if (rc) @@ -2618,10 +2620,18 @@ int policydb_read(struct policydb *p, void *fp) goto bad; rc = -EINVAL; - p->process_trans_perms = string_to_av_perm(p, p->process_class, "transition"); - p->process_trans_perms |= string_to_av_perm(p, p->process_class, "dyntransition"); - if (!p->process_trans_perms) + perm = string_to_av_perm(p, p->process_class, "transition"); + if (!perm) { + pr_err("SELinux: process transition permission is required, not defined in policy\n"); + goto bad; + } + p->process_trans_perms = perm; + perm = string_to_av_perm(p, p->process_class, "dyntransition"); + if (!perm) { + pr_err("SELinux: process dyntransition permission is required, not defined in policy\n"); goto bad; + } + p->process_trans_perms |= perm; rc = ocontext_read(p, info, fp); if (rc) -- 2.39.5