From 38bead4b88bdfca463c26d0ba6eeadb498669548 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Thu, 10 Oct 2024 20:35:00 +0200 Subject: [PATCH] hwmon: (lm95234) Fix underflows seen when writing limit attributes [ Upstream commit af64e3e1537896337405f880c1e9ac1f8c0c6198 ] DIV_ROUND_CLOSEST() after kstrtol() results in an underflow if a large negative number such as -9223372036854775808 is provided by the user. Fix it by reordering clamp_val() and DIV_ROUND_CLOSEST() operations. Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin CVE-2024-46758 (cherry picked from commit 16f42953231be1e7be77bc24005270d9e0d9d2ee linux-6.10.y) Signed-off-by: Bethany Jamison Acked-by: Guoqing Jiang Acked-by: ivanhu Signed-off-by: Stefan Bader --- drivers/hwmon/lm95234.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/hwmon/lm95234.c b/drivers/hwmon/lm95234.c index 67b9d7636ee4..37e8e9679aeb 100644 --- a/drivers/hwmon/lm95234.c +++ b/drivers/hwmon/lm95234.c @@ -301,7 +301,8 @@ static ssize_t tcrit2_store(struct device *dev, struct device_attribute *attr, if (ret < 0) return ret; - val = clamp_val(DIV_ROUND_CLOSEST(val, 1000), 0, index ? 255 : 127); + val = DIV_ROUND_CLOSEST(clamp_val(val, 0, (index ? 255 : 127) * 1000), + 1000); mutex_lock(&data->update_lock); data->tcrit2[index] = val; @@ -350,7 +351,7 @@ static ssize_t tcrit1_store(struct device *dev, struct device_attribute *attr, if (ret < 0) return ret; - val = clamp_val(DIV_ROUND_CLOSEST(val, 1000), 0, 255); + val = DIV_ROUND_CLOSEST(clamp_val(val, 0, 255000), 1000); mutex_lock(&data->update_lock); data->tcrit1[index] = val; @@ -391,7 +392,7 @@ static ssize_t tcrit1_hyst_store(struct device *dev, if (ret < 0) return ret; - val = DIV_ROUND_CLOSEST(val, 1000); + val = DIV_ROUND_CLOSEST(clamp_val(val, -255000, 255000), 1000); val = clamp_val((int)data->tcrit1[index] - val, 0, 31); mutex_lock(&data->update_lock); @@ -431,7 +432,7 @@ static ssize_t offset_store(struct device *dev, struct device_attribute *attr, return ret; /* Accuracy is 1/2 degrees C */ - val = clamp_val(DIV_ROUND_CLOSEST(val, 500), -128, 127); + val = DIV_ROUND_CLOSEST(clamp_val(val, -64000, 63500), 500); mutex_lock(&data->update_lock); data->toffset[index] = val;