Piteball/android_kernel_samsung_msm8976
1
1
Fork 0
mirror of https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git synced 2024-11-07 04:09:21 +00:00
Code Issues Projects Releases Wiki Activity

sched/autogroup: Fix possible Spectre-v1 indexing for sched_prio_to_weight[]

Browse source 
commit 354d7793070611b4df5a79fbb0f12752d0ed0cc5 upstream.

> kernel/sched/autogroup.c:230 proc_sched_autogroup_set_nice() warn: potential spectre issue 'sched_prio_to_weight'

Userspace controls @nice, sanitize the array index.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.16: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This commit is contained in:
Peter Zijlstra 2018-04-20 15:03:45 +02:00 committed by syphyr
parent 0025b68cb9
commit e1989d554d
1 changed files with 5 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

7
kernel/sched/auto_group.c
View file

@ -8,6 +8,7 @@
#include <linux/utsname.h>
#include <linux/security.h>
#include <linux/export.h>
#include <linux/nospec.h>
unsigned int __read_mostly sysctl_sched_autogroup_enabled = 1;
static struct autogroup autogroup_default;
@ -202,7 +203,7 @@ int proc_sched_autogroup_set_nice(struct task_struct *p, int nice)
static unsigned long next = INITIAL_JIFFIES;
struct autogroup *ag;
unsigned long shares;
int err;
int err, idx;
if (nice < -20 || nice > 19)
return -EINVAL;
@ -220,7 +221,9 @@ int proc_sched_autogroup_set_nice(struct task_struct *p, int nice)
next = HZ / 10 + jiffies;
ag = autogroup_task_get(p);
shares = scale_load(prio_to_weight[nice + 20]);
idx = array_index_nospec(nice + 20, 40);
shares = scale_load(prio_to_weight[idx]);
down_write(&ag->lock);
err = sched_group_set_shares(ag->tg, shares);