From bd6515226a237a57458c315726d0ca7b28e1e5da Mon Sep 17 00:00:00 2001 From: Dmitry Kasatkin Date: Fri, 14 Mar 2014 17:44:49 +0000 Subject: [PATCH] smack: fix key permission verification For any keyring access type SMACK always used MAY_READWRITE access check. It prevents reading the key with label "_", which should be allowed for anyone. This patch changes default access check to MAY_READ and use MAY_READWRITE in only appropriate cases. Change-Id: Ie357956730df93058198e2df13ef307ce4e8f675 Signed-off-by: Dmitry Kasatkin Signed-off-by: David Howells Acked-by: Casey Schaufler Signed-off-by: Rafal Krypa (cherry picked from commit 424538354be6c42da48b302ef1ac939931599797) Signed-off-by: Damian Hobson-Garcia --- security/smack/smack_lsm.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index eabb97f..c972a71 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -3519,6 +3519,7 @@ static int smack_key_permission(key_ref_t key_ref, struct key *keyp; struct smk_audit_info ad; struct smack_known *tkp = smk_of_task(cred->security); + int request = 0; keyp = key_ref_to_ptr(key_ref); if (keyp == NULL) @@ -3539,7 +3540,11 @@ static int smack_key_permission(key_ref_t key_ref, ad.a.u.key_struct.key = keyp->serial; ad.a.u.key_struct.key_desc = keyp->description; #endif - return smk_access(tkp, keyp->security, MAY_READWRITE, &ad); + if (perm & KEY_NEED_READ) + request = MAY_READ; + if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR)) + request = MAY_WRITE; + return smk_access(tkp, keyp->security, request, &ad); } #endif /* CONFIG_KEYS */ -- 2.7.4