3.16.60-rc1 review patch. If anyone has any objections, please let me know.
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From: Peter Zijlstra peterz@infradead.org
commit 7281c8dec8a87685cb54d503d8cceef5a0fc2fdd upstream.
kernel/sched/core.c:6921 cpu_weight_nice_write_s64() warn: potential spectre issue 'sched_prio_to_weight'
Userspace controls @nice, so sanitize the value before using it to index an array.
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: Mike Galbraith efault@gmx.de Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar mingo@kernel.org [bwh: Backported to 3.16: Vulnerable array lookup is in set_load_weight()] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -74,6 +74,7 @@ #include <linux/binfmts.h> #include <linux/context_tracking.h> #include <linux/compiler.h> +#include <linux/nospec.h>
#include <asm/switch_to.h> #include <asm/tlb.h> @@ -820,6 +821,8 @@ static void set_load_weight(struct task_ return; }
+ prio = array_index_nospec(prio, 40); + load->weight = scale_load(prio_to_weight[prio]); load->inv_weight = prio_to_wmult[prio]; }