diff mbox series

[PULL,1/2] hw/misc: use extract64 instead of 1 << i

Message ID 20250317152111.316627-2-pbonzini@redhat.com (mailing list archive)
State New
Headers show
Series [PULL,1/2] hw/misc: use extract64 instead of 1 << i | expand

Commit Message

Paolo Bonzini March 17, 2025, 3:21 p.m. UTC
From: Tigran Sogomonian <tsogomonian@astralinux.ru>

1 << i is casted to uint64_t while bitwise and with val.
So this value may become 0xffffffff80000000 but only
31th "start" bit is required.
Use the bitfield extract() API instead.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Tigran Sogomonian <tsogomonian@astralinux.ru>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Link: https://lore.kernel.org/r/20241227104618.2526-1-tsogomonian@astralinux.ru
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 hw/misc/mps2-fpgaio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/hw/misc/mps2-fpgaio.c b/hw/misc/mps2-fpgaio.c
index d07568248d6..04a3da5db05 100644
--- a/hw/misc/mps2-fpgaio.c
+++ b/hw/misc/mps2-fpgaio.c
@@ -198,7 +198,7 @@  static void mps2_fpgaio_write(void *opaque, hwaddr offset, uint64_t value,
 
             s->led0 = value & MAKE_64BIT_MASK(0, s->num_leds);
             for (i = 0; i < s->num_leds; i++) {
-                led_set_state(s->led[i], value & (1 << i));
+                led_set_state(s->led[i], extract64(value, i, 1));
             }
         }
         break;