In ni_tio_set_clock_src() clock period is a subject to overflow because
'period_ns' (which comes from user, may have any value and is not
validated anywhere) is not cast to a larger data type before performing
arithmetic.
Cast 'period_ns' to u64 to prevent overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 3e90b1c7ebe9 ("staging: comedi: ni_tio: tidy up ni_tio_set_clock_src() and helpers")
Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru>
---
v1->v2: Remove "staging:" from the title,
add "Reviewed-by: Ian Abbott <abbotti@mev.co.uk>"
(https://lore.kernel.org/all/5c3172d8-517f-4d23-a713-fc41406c00d8@mev.co.uk/)
drivers/comedi/drivers/ni_tio.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/comedi/drivers/ni_tio.c b/drivers/comedi/drivers/ni_tio.c
index da6826d77e60..98b5b44416cf 100644
--- a/drivers/comedi/drivers/ni_tio.c
+++ b/drivers/comedi/drivers/ni_tio.c
@@ -800,7 +800,7 @@ static int ni_tio_set_clock_src(struct ni_gpct *counter,
GI_PRESCALE_X2(counter_dev->variant) |
GI_PRESCALE_X8(counter_dev->variant), bits);
}
- counter->clock_period_ps = period_ns * 1000;
+ counter->clock_period_ps = (u64)period_ns * 1000;
ni_tio_set_sync_mode(counter);
return 0;
}
--
2.30.2