diff options
| author | Stephen Smalley <sds@tycho.nsa.gov> | 2018-12-12 16:10:56 +0100 |
|---|---|---|
| committer | Paul Moore <paul@paul-moore.com> | 2019-01-11 02:34:37 +0100 |
| commit | e46e01eebbbcf2ff6d28ee7cae9f117e9d1572c8 (patch) | |
| tree | 21fb06603d0a98d0146053922e1a93ba5ded5817 /security | |
| parent | selinux: avoid silent denials in permissive mode under RCU walk (diff) | |
| download | linux-e46e01eebbbcf2ff6d28ee7cae9f117e9d1572c8.tar.xz linux-e46e01eebbbcf2ff6d28ee7cae9f117e9d1572c8.zip | |
selinux: stop passing MAY_NOT_BLOCK to the AVC upon follow_link
commit bda0be7ad9948 ("security: make inode_follow_link RCU-walk aware")
switched selinux_inode_follow_link() to use avc_has_perm_flags() and
pass down the MAY_NOT_BLOCK flag if called during RCU walk. However,
the only test of MAY_NOT_BLOCK occurs during slow_avc_audit()
and only if passing an inode as audit data (LSM_AUDIT_DATA_INODE). Since
selinux_inode_follow_link() passes a dentry directly, passing MAY_NOT_BLOCK
here serves no purpose. Switch selinux_inode_follow_link() to use
avc_has_perm() and drop avc_has_perm_flags() since there are no other
users.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Diffstat (limited to 'security')
| -rw-r--r-- | security/selinux/avc.c | 24 | ||||
| -rw-r--r-- | security/selinux/hooks.c | 5 | ||||
| -rw-r--r-- | security/selinux/include/avc.h | 5 |
3 files changed, 4 insertions, 30 deletions
diff --git a/security/selinux/avc.c b/security/selinux/avc.c index 5de18a6d5c3f..9b63d8ee1687 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -867,9 +867,8 @@ static int avc_update_node(struct selinux_avc *avc, * permissive mode that only appear when in enforcing mode. * * See the corresponding handling in slow_avc_audit(), and the - * logic in selinux_inode_follow_link and selinux_inode_permission - * for the VFS MAY_NOT_BLOCK flag, which is transliterated into - * AVC_NONBLOCKING for avc_has_perm_noaudit(). + * logic in selinux_inode_permission for the MAY_NOT_BLOCK flag, + * which is transliterated into AVC_NONBLOCKING. */ if (flags & AVC_NONBLOCKING) return 0; @@ -1209,25 +1208,6 @@ int avc_has_perm(struct selinux_state *state, u32 ssid, u32 tsid, u16 tclass, return rc; } -int avc_has_perm_flags(struct selinux_state *state, - u32 ssid, u32 tsid, u16 tclass, u32 requested, - struct common_audit_data *auditdata, - int flags) -{ - struct av_decision avd; - int rc, rc2; - - rc = avc_has_perm_noaudit(state, ssid, tsid, tclass, requested, - (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0, - &avd); - - rc2 = avc_audit(state, ssid, tsid, tclass, requested, &avd, rc, - auditdata, flags); - if (rc2) - return rc2; - return rc; -} - u32 avc_policy_seqno(struct selinux_state *state) { return state->avc->avc_cache.latest_notif; diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 7f6068489a02..f08a0f201967 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2925,9 +2925,8 @@ static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode, if (IS_ERR(isec)) return PTR_ERR(isec); - return avc_has_perm_flags(&selinux_state, - sid, isec->sid, isec->sclass, FILE__READ, &ad, - rcu ? MAY_NOT_BLOCK : 0); + return avc_has_perm(&selinux_state, + sid, isec->sid, isec->sclass, FILE__READ, &ad); } static noinline int audit_inode_permission(struct inode *inode, diff --git a/security/selinux/include/avc.h b/security/selinux/include/avc.h index 74ea50977c20..7be0e1e90e8b 100644 --- a/security/selinux/include/avc.h +++ b/security/selinux/include/avc.h @@ -153,11 +153,6 @@ int avc_has_perm(struct selinux_state *state, u32 ssid, u32 tsid, u16 tclass, u32 requested, struct common_audit_data *auditdata); -int avc_has_perm_flags(struct selinux_state *state, - u32 ssid, u32 tsid, - u16 tclass, u32 requested, - struct common_audit_data *auditdata, - int flags); int avc_has_extended_perms(struct selinux_state *state, u32 ssid, u32 tsid, u16 tclass, u32 requested, |