Patch "interconnect: qcom: rpm: Prevent integer overflow in rate" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    interconnect: qcom: rpm: Prevent integer overflow in rate

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     interconnect-qcom-rpm-prevent-integer-overflow-in-ra.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit d18d7f794c2cc37c7b064f948aa778919f8219d6
Author: Stephan Gerhold <stephan@xxxxxxxxxxx>
Date:   Mon Dec 6 12:45:42 2021 +0100

    interconnect: qcom: rpm: Prevent integer overflow in rate
    
    [ Upstream commit a7d9436a6c85fcb8843c910fd323dcd7f839bf63 ]
    
    Using icc-rpm on ARM32 currently results in clk_set_rate() errors during
    boot, e.g. "bus clk_set_rate error: -22". This is very similar to commit
    7381e27b1e56 ("interconnect: qcom: msm8974: Prevent integer overflow in rate")
    where the u64 is converted to a signed long during clock rate rounding,
    resulting in an overflow on 32-bit platforms.
    
    Let's fix it similarly by making sure that the rate does not exceed
    LONG_MAX. Such high clock rates will surely result in the maximum
    frequency of the bus anyway.
    
    Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20211206114542.45325-1-stephan@xxxxxxxxxxx
    Signed-off-by: Georgi Djakov <djakov@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/interconnect/qcom/icc-rpm.c b/drivers/interconnect/qcom/icc-rpm.c
index 54de49ca7808a..ddf1805ded0c0 100644
--- a/drivers/interconnect/qcom/icc-rpm.c
+++ b/drivers/interconnect/qcom/icc-rpm.c
@@ -68,6 +68,7 @@ static int qcom_icc_set(struct icc_node *src, struct icc_node *dst)
 	rate = max(sum_bw, max_peak_bw);
 
 	do_div(rate, qn->buswidth);
+	rate = min_t(u64, rate, LONG_MAX);
 
 	if (qn->rate == rate)
 		return 0;