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Subject[GIT PULL] timer fix
Linus,

Please pull the latest timers-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers-urgent-for-linus

# HEAD: 19b558db12f9f4e45a22012bae7b4783e62224da posix-timers: Protect posix clock array access against speculation

Make posix clock ID usage Spectre-safe.

Thanks,

Ingo

------------------>
Thomas Gleixner (1):
posix-timers: Protect posix clock array access against speculation


kernel/time/posix-timers.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 75043046914e..10b7186d0638 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -50,6 +50,7 @@
#include <linux/export.h>
#include <linux/hashtable.h>
#include <linux/compat.h>
+#include <linux/nospec.h>

#include "timekeeping.h"
#include "posix-timers.h"
@@ -1346,11 +1347,15 @@ static const struct k_clock * const posix_clocks[] = {

static const struct k_clock *clockid_to_kclock(const clockid_t id)
{
- if (id < 0)
+ clockid_t idx = id;
+
+ if (id < 0) {
return (id & CLOCKFD_MASK) == CLOCKFD ?
&clock_posix_dynamic : &clock_posix_cpu;
+ }

- if (id >= ARRAY_SIZE(posix_clocks) || !posix_clocks[id])
+ if (id >= ARRAY_SIZE(posix_clocks))
return NULL;
- return posix_clocks[id];
+
+ return posix_clocks[array_index_nospec(idx, ARRAY_SIZE(posix_clocks))];
}
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