The following commit has been merged into the irq/urgent branch of tip:

Commit-ID: b9cc7d8a4656a6e815852c27ab50365009cb69c1 Gitweb: https://git.kernel.org/tip/b9cc7d8a4656a6e815852c27ab50365009cb69c1 Author: Ben Dai ben.dai@unisoc.com AuthorDate: Sun, 25 Apr 2021 23:09:03 +08:00 Committer: Thomas Gleixner tglx@linutronix.de CommitterDate: Tue, 10 Aug 2021 15:39:00 +02:00

genirq/timings: Prevent potential array overflow in __irq_timings_store()

When the interrupt interval is greater than 2 ^ PREDICTION_BUFFER_SIZE * PREDICTION_FACTOR us and less than 1s, the calculated index will be greater than the length of irqs->ema_time[]. Check the calculated index before using it to prevent array overflow.

Fixes: 23aa3b9a6b7d ("genirq/timings: Encapsulate storing function") Signed-off-by: Ben Dai ben.dai@unisoc.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210425150903.25456-1-ben.dai9703@gmail.com

--- kernel/irq/timings.c | 5 +++++ 1 file changed, 5 insertions(+)

diff --git a/kernel/irq/timings.c b/kernel/irq/timings.c index d309d6f..4d2a702 100644 --- a/kernel/irq/timings.c +++ b/kernel/irq/timings.c @@ -453,6 +453,11 @@ static __always_inline void __irq_timings_store(int irq, struct irqt_stat *irqs, */ index = irq_timings_interval_index(interval);

+ if (index > PREDICTION_BUFFER_SIZE - 1) { + irqs->count = 0; + return; + } + /* * Store the index as an element of the pattern in another * circular array.