linux-kernel - [ 31/59] fcaps: clear the same personality flags as suid when fcaps are used

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20120419210613.745592080@linuxfoundation.org>
Date:	Thu, 19 Apr 2012 14:06:42 -0700
From:	Greg KH <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:	torvalds@...ux-foundation.org, akpm@...ux-foundation.org,
	alan@...rguk.ukuu.org.uk, Eric Paris <eparis@...hat.com>,
	Serge Hallyn <serge.hallyn@...onical.com>,
	James Morris <james.l.morris@...cle.com>
Subject: [ 31/59] fcaps: clear the same personality flags as suid when fcaps are used

3.0-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Paris <eparis@...hat.com>

commit d52fc5dde171f030170a6cb78034d166b13c9445 upstream.

If a process increases permissions using fcaps all of the dangerous
personality flags which are cleared for suid apps should also be cleared.
Thus programs given priviledge with fcaps will continue to have address space
randomization enabled even if the parent tried to disable it to make it
easier to attack.

Signed-off-by: Eric Paris <eparis@...hat.com>
Reviewed-by: Serge Hallyn <serge.hallyn@...onical.com>
Signed-off-by: James Morris <james.l.morris@...cle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 security/commoncap.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -510,6 +510,11 @@ int cap_bprm_set_creds(struct linux_binp
 	}
 skip:
 
+	/* if we have fs caps, clear dangerous personality flags */
+	if (!cap_issubset(new->cap_permitted, old->cap_permitted))
+		bprm->per_clear |= PER_CLEAR_ON_SETID;
+
+
 	/* Don't let someone trace a set[ug]id/setpcap binary with the revised
 	 * credentials unless they have the appropriate permit
 	 */


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/