diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2018-04-20 15:03:45 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-16 10:12:35 +0200 |
| commit | 8577c7a3191dd08b9e5a246630cdd628f248a94f (patch) | |
| tree | 2893dcaf473bb1044c5cc1c5413b37d784ae05dc | |
| parent | 5d728a4ecab107668f241c6d2a10cc9380830c25 (diff) | |
sched/autogroup: Fix possible Spectre-v1 indexing for sched_prio_to_weight[]
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>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/sched/autogroup.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/kernel/sched/autogroup.c b/kernel/sched/autogroup.c index bb4b9fe026a1..e3d1ba7e3a94 100644 --- a/kernel/sched/autogroup.c +++ b/kernel/sched/autogroup.c @@ -4,6 +4,7 @@ #include <linux/utsname.h> #include <linux/security.h> #include <linux/export.h> +#include <linux/nospec.h> #include "sched.h" @@ -212,7 +213,7 @@ 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 < MIN_NICE || nice > MAX_NICE) return -EINVAL; @@ -230,7 +231,9 @@ int proc_sched_autogroup_set_nice(struct task_struct *p, int nice) next = HZ / 10 + jiffies; ag = autogroup_task_get(p); - shares = scale_load(sched_prio_to_weight[nice + 20]); + + idx = array_index_nospec(nice + 20, 40); + shares = scale_load(sched_prio_to_weight[idx]); down_write(&ag->lock); err = sched_group_set_shares(ag->tg, shares); |