From: Tianjia Zhang tianjia.zhang@linux.alibaba.com
stable inclusion from linux-4.19.207 commit f3f5947867d58b75f0e8cf610f067094ede4dce3
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[ Upstream commit 6d14f5c7028eea70760df284057fe198ce7778dd ]
In the smk_access_entry() function, if no matching rule is found in the rust_list, a negative error code will be used to perform bit operations with the MAY_ enumeration value. This is semantically wrong. This patch fixes this issue.
Signed-off-by: Tianjia Zhang tianjia.zhang@linux.alibaba.com Signed-off-by: Casey Schaufler casey@schaufler-ca.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- security/smack/smack_access.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index a7855c61c05cd..07d23b4f76f3b 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -85,23 +85,22 @@ int log_policy = SMACK_AUDIT_DENIED; int smk_access_entry(char *subject_label, char *object_label, struct list_head *rule_list) { - int may = -ENOENT; struct smack_rule *srp;
list_for_each_entry_rcu(srp, rule_list, list) { if (srp->smk_object->smk_known == object_label && srp->smk_subject->smk_known == subject_label) { - may = srp->smk_access; - break; + int may = srp->smk_access; + /* + * MAY_WRITE implies MAY_LOCK. + */ + if ((may & MAY_WRITE) == MAY_WRITE) + may |= MAY_LOCK; + return may; } }
- /* - * MAY_WRITE implies MAY_LOCK. - */ - if ((may & MAY_WRITE) == MAY_WRITE) - may |= MAY_LOCK; - return may; + return -ENOENT; }
/**