If the value of the clock variable is higher than 800000, the value of the
variable m, which is used as a divisor, will remain zero, because
(clock * testp) will be higher than vcomax in every loop iteration, which
leads to skipping every iteration and leaving variable m unmodified.
Return -EINVAL just after the loop, if m is still 0.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: e829d7ef9f17 ("drm/mgag200: Add support for a new rev of G200e")
Signed-off-by: Murad Masimov <m.masimov@xxxxxxxxx>
---
drivers/gpu/drm/mgag200/mgag200_g200se.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/mgag200/mgag200_g200se.c b/drivers/gpu/drm/mgag200/mgag200_g200se.c
index 7a32d3b1d226..4d65ead63d66 100644
--- a/drivers/gpu/drm/mgag200/mgag200_g200se.c
+++ b/drivers/gpu/drm/mgag200/mgag200_g200se.c
@@ -249,6 +249,9 @@ static int mgag200_g200se_04_pixpllc_atomic_check(struct drm_crtc *crtc,
}
}
+ if (m == 0)
+ return -EINVAL;
+
fvv = pllreffreq * n / m;
fvv = (fvv - 800000) / 50000;
if (fvv > 15)
--
2.39.2
