This is a note to let you know that I've just added the patch titled net: stmmac: gmac5+: fix potential integer overflow on 32 bit multiply to the 5.6-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: net-stmmac-gmac5-fix-potential-integer-overflow-on-3.patch and it can be found in the queue-5.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 880b21a3a7a5fefa900b2393b48d80eb7a755a51 Author: Colin Ian King <colin.king@xxxxxxxxxxxxx> Date: Fri May 1 15:10:16 2020 +0100 net: stmmac: gmac5+: fix potential integer overflow on 32 bit multiply [ Upstream commit 44d95cc6b10ff7439d45839c96c581cb4368c088 ] The multiplication of cfg->ctr[1] by 1000000000 is performed using a 32 bit multiplication (since cfg->ctr[1] is a u32) and this can lead to a potential overflow. Fix this by making the constant a ULL to ensure a 64 bit multiply occurs. Fixes: 504723af0d85 ("net: stmmac: Add basic EST support for GMAC5+") Addresses-Coverity: ("Unintentional integer overflow") Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac5.c b/drivers/net/ethernet/stmicro/stmmac/dwmac5.c index 494c859b4ade8..67ba67ed0cb99 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac5.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac5.c @@ -624,7 +624,7 @@ int dwmac5_est_configure(void __iomem *ioaddr, struct stmmac_est *cfg, total_offset += offset; } - total_ctr = cfg->ctr[0] + cfg->ctr[1] * 1000000000; + total_ctr = cfg->ctr[0] + cfg->ctr[1] * 1000000000ULL; total_ctr += total_offset; ctr_low = do_div(total_ctr, 1000000000);