This is a note to let you know that I've just added the patch titled
ssb: Fix division by zero issue in ssb_calc_clock_rate
to the 4.19-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:
ssb-fix-division-by-zero-issue-in-ssb_calc_clock_rat.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 9dd10c77c02d22a18d886c267070855c2ec7e66a
Author: Rand Deeb <rand.sec96@xxxxxxxxx>
Date: Tue Sep 5 02:23:46 2023 +0300
ssb: Fix division by zero issue in ssb_calc_clock_rate
[ Upstream commit e0b5127fa134fe0284d58877b6b3133939c8b3ce ]
In ssb_calc_clock_rate(), there is a potential issue where the value of
m1 could be zero due to initialization using clkfactor_f6_resolv(). This
situation raised concerns about the possibility of a division by zero
error.
We fixed it by following the suggestions provided by Larry Finger
<Larry.Finger@xxxxxxxxxxxx> and Michael Büsch <m@xxxxxxx>. The fix
involves returning a value of 1 instead of 0 in clkfactor_f6_resolv().
This modification ensures the proper functioning of the code and
eliminates the risk of division by zero errors.
Signed-off-by: Rand Deeb <rand.sec96@xxxxxxxxx>
Acked-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
Acked-by: Michael Büsch <m@xxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230904232346.34991-1-rand.sec96@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/ssb/main.c b/drivers/ssb/main.c
index 0a26984acb2ca..9e54bc7eec663 100644
--- a/drivers/ssb/main.c
+++ b/drivers/ssb/main.c
@@ -835,7 +835,7 @@ static u32 clkfactor_f6_resolve(u32 v)
case SSB_CHIPCO_CLK_F6_7:
return 7;
}
- return 0;
+ return 1;
}
/* Calculate the speed the backplane would run at a given set of clockcontrol values */
