The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From fb14528e443646dd3fd02df4437fcf5265b66baa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= <mic@xxxxxxxxxxxxxxxxxxx>
Date: Fri, 30 Oct 2020 13:38:49 +0100
Subject: [PATCH] seccomp: Set PF_SUPERPRIV when checking capability
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Replace the use of security_capable(current_cred(), ...) with
ns_capable_noaudit() which set PF_SUPERPRIV.
Since commit 98f368e9e263 ("kernel: Add noaudit variant of
ns_capable()"), a new ns_capable_noaudit() helper is available. Let's
use it!
Cc: Jann Horn <jannh@xxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Tyler Hicks <tyhicks@xxxxxxxxxxxxxxxxxxx>
Cc: Will Drewry <wad@xxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: e2cfabdfd075 ("seccomp: add system call filtering using BPF")
Signed-off-by: Mickaël Salaün <mic@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Jann Horn <jannh@xxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201030123849.770769-3-mic@xxxxxxxxxxx
diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 8ad7a293255a..53a7d1512dd7 100644
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -38,7 +38,7 @@
#include <linux/filter.h>
#include <linux/pid.h>
#include <linux/ptrace.h>
-#include <linux/security.h>
+#include <linux/capability.h>
#include <linux/tracehook.h>
#include <linux/uaccess.h>
#include <linux/anon_inodes.h>
@@ -558,8 +558,7 @@ static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog)
* behavior of privileged children.
*/
if (!task_no_new_privs(current) &&
- security_capable(current_cred(), current_user_ns(),
- CAP_SYS_ADMIN, CAP_OPT_NOAUDIT) != 0)
+ !ns_capable_noaudit(current_user_ns(), CAP_SYS_ADMIN))
return ERR_PTR(-EACCES);
/* Allocate a new seccomp_filter */
