The patch titled
Subject: fs/proc/base.c: use ns_capable instead of capable for timerslack_ns
has been added to the -mm tree. Its filename is
proc-use-ns_capable-instead-of-capable-for-timerslack_ns.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/proc-use-ns_capable-instead-of-capable-for-timerslack_ns.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/proc-use-ns_capable-instead-of-capable-for-timerslack_ns.patch
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------------------------------------------------------
From: Benjamin Gordon <bmgordon@xxxxxxxxxx>
Subject: fs/proc/base.c: use ns_capable instead of capable for timerslack_ns
Access to timerslack_ns is controlled by a process having CAP_SYS_NICE in
its effective capability set, but the current check looks in the root
namespace instead of the process' user namespace. Since a process is
allowed to do other activities controlled by CAP_SYS_NICE inside a
namespace, it should also be able to adjust timerslack_ns.
Link: http://lkml.kernel.org/r/20181030180012.232896-1-bmgordon@xxxxxxxxxx
Signed-off-by: Benjamin Gordon <bmgordon@xxxxxxxxxx>
Acked-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Cc: John Stultz <john.stultz@xxxxxxxxxx>
Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: "Serge E. Hallyn" <serge@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Oren Laadan <orenl@xxxxxxxxxxx>
Cc: Ruchi Kandoi <kandoiruchi@xxxxxxxxxx>
Cc: Rom Lemarchand <romlem@xxxxxxxxxxx>
Cc: Todd Kjos <tkjos@xxxxxxxxxx>
Cc: Colin Cross <ccross@xxxxxxxxxxx>
Cc: Nick Kralevich <nnk@xxxxxxxxxx>
Cc: Dmitry Shmidt <dimitrysh@xxxxxxxxxx>
Cc: Elliott Hughes <enh@xxxxxxxxxx>
Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/proc/base.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
--- a/fs/proc/base.c~proc-use-ns_capable-instead-of-capable-for-timerslack_ns
+++ a/fs/proc/base.c
@@ -2356,10 +2356,13 @@ static ssize_t timerslack_ns_write(struc
return -ESRCH;
if (p != current) {
- if (!capable(CAP_SYS_NICE)) {
+ rcu_read_lock();
+ if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
+ rcu_read_unlock();
count = -EPERM;
goto out;
}
+ rcu_read_unlock();
err = security_task_setscheduler(p);
if (err) {
@@ -2392,11 +2395,14 @@ static int timerslack_ns_show(struct seq
return -ESRCH;
if (p != current) {
-
- if (!capable(CAP_SYS_NICE)) {
+ rcu_read_lock();
+ if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) {
+ rcu_read_unlock();
err = -EPERM;
goto out;
}
+ rcu_read_unlock();
+
err = security_task_getscheduler(p);
if (err)
goto out;
_
Patches currently in -mm which might be from bmgordon@xxxxxxxxxx are
proc-use-ns_capable-instead-of-capable-for-timerslack_ns.patch
