From f3bef67992e8698897b584616535803887c4a73e Mon Sep 17 00:00:00 2001 From: Stephen Smalley Date: Mon, 23 Nov 2015 16:07:41 -0500 Subject: [PATCH] selinux: fix bug in conditional rules handling commit fa1aa143ac4a ("selinux: extended permissions for ioctls") introduced a bug into the handling of conditional rules, skipping the processing entirely when the caller does not provide an extended permissions (xperms) structure. Access checks from userspace using /sys/fs/selinux/access do not include such a structure since that interface does not presently expose extended permission information. As a result, conditional rules were being ignored entirely on userspace access requests, producing denials when access was allowed by conditional rules in the policy. Fix the bug by only skipping computation of extended permissions in this situation, not the entire conditional rules processing. Reported-by: Laurent Bigonville Signed-off-by: Stephen Smalley [PM: fixed long lines in patch description] Cc: stable@vger.kernel.org # 4.3 Signed-off-by: Paul Moore --- security/selinux/ss/conditional.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c index 18643bf9894d..456e1a9bcfde 100644 --- a/security/selinux/ss/conditional.c +++ b/security/selinux/ss/conditional.c @@ -638,7 +638,7 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key, { struct avtab_node *node; - if (!ctab || !key || !avd || !xperms) + if (!ctab || !key || !avd) return; for (node = avtab_search_node(ctab, key); node; @@ -657,7 +657,7 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key, if ((u16)(AVTAB_AUDITALLOW|AVTAB_ENABLED) == (node->key.specified & (AVTAB_AUDITALLOW|AVTAB_ENABLED))) avd->auditallow |= node->datum.u.data; - if ((node->key.specified & AVTAB_ENABLED) && + if (xperms && (node->key.specified & AVTAB_ENABLED) && (node->key.specified & AVTAB_XPERMS)) services_compute_xperms_drivers(xperms, node); }